FB/EK HOLDEN STROMBERG CARBURETTION ENTHUSIASTS GUIDEREVISION 0 DATE October 2011 UPDATE Initial draft for review. 1 Table of Contents 1 2 3 3.1 3.2 3.3 4 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 5 5.1 6 6.1 6.2 7 7.1 7.2 7.3 7.4 7.5 7.6 7.7 7.8 7.9 8 8.1 8.2 8.3 8.4 8.5 8.6 8.7 8.8 8.9 9 10 10.1 10.2 10.3 10.4 10.5 10.6 10.7 10.8 11 12 13 14 Background .................................................................................................................................................................. 3 Not all Strombergs Are Equal… the Zenith Connection ........................................................................................... 4 Decoding ...................................................................................................................................................................... 5 Stromberg Carburettor Model Numbers .................................................................................................................... 5 Australian Stromberg Carburettor Codes .................................................................................................................. 6 US Stromberg Carburettor Codes ........................................................................................................................... 14 Operation .................................................................................................................................................................... 15 BXOV-1 Main Components ..................................................................................................................................... 15 BXUV-2 and BXV-2 Main Components ................................................................................................................... 17 Float System ........................................................................................................................................................... 18 Idle System ............................................................................................................................................................. 18 Main Metering System............................................................................................................................................. 19 Accelerating System ............................................................................................................................................... 20 Power System ......................................................................................................................................................... 21 Choke System ......................................................................................................................................................... 21 Spacer..................................................................................................................................................................... 22 Early Holden Stromberg Factory Specifications ..................................................................................................... 23 EH Holden S4 Carburettor ...................................................................................................................................... 33 Assembly Diagrams................................................................................................................................................... 34 BXOV-1 Assembly Diagram .................................................................................................................................... 34 BXUV-2/BXV-2 Assembly Diagram ......................................................................................................................... 35 Disassembly and Overhaul Process ........................................................................................................................ 38 Kit Contents and Pre-disassembly .......................................................................................................................... 38 Special Tools........................................................................................................................................................... 40 Removing the Carburettor from the Vehicle ............................................................................................................ 41 Disassembling the Air Horn ..................................................................................................................................... 41 Disassembling the Main Body ................................................................................................................................. 42 Disassembling the Throttle Body ............................................................................................................................. 44 Cleaning and Inspection .......................................................................................................................................... 45 Assembly and Reinstallation ................................................................................................................................... 46 Replacement Parts .................................................................................................................................................. 48 Tuning and Troubleshooting .................................................................................................................................... 52 Fuel Level ............................................................................................................................................................... 52 Idle Speed and Idle Mixture ..................................................................................................................................... 55 Accelerator Pump Stroke and Components ............................................................................................................ 56 Idle Vent Valve Lift .................................................................................................................................................. 59 Wide-Open Throttle (WOT) Adjustment................................................................................................................... 59 Main Metering Jets .................................................................................................................................................. 62 Power Bypass Jets .................................................................................................................................................. 66 Vacuum Power Piston ............................................................................................................................................. 68 Troubleshooting ...................................................................................................................................................... 70 Bigger Stromberg Swap ............................................................................................................................................ 79 Multiple Carburettors (Twins and Triples) ........................................................................................................... 81 Carburettor Model and Manifold Choice .................................................................................................................. 81 Linkages .................................................................................................................................................................. 82 Accelerator Linkage to Cable Modification .............................................................................................................. 88 Fuel and Vacuum Lines ........................................................................................................................................... 89 Venturi Sleeves ....................................................................................................................................................... 90 Synchronisation....................................................................................................................................................... 91 Tuning ..................................................................................................................................................................... 92 Examples of Twin and Triple Setups (Stromberg Porn) ........................................................................................... 94 “The Joker” Carburettor Lock ............................................................................................................................ 127 Holden Part Numbers.......................................................................................................................................... 128 Bendix Stromberg Part Numbers ....................................................................................................................... 136 Contacts ............................................................................................................................................................... 148 2 1 Background This document aims to provide some information regarding carburettors suitable for FB and EK Holdens. It contains: historical information, such as which carburettors and fittings were fitted to different model Holdens, practical information on identification, disassembly and reassembly of early Holden original and replacement carburettors, and guidance on tuning, replacement parts and overhaul techniques. It contains answers to many of the questions that seem to come up routinely on most of the early Holden forums: “What jets should I run in my early Holden, and where do I get them from?” “Why is my Stromberg carburettor running so poorly?” “How do I set up twin carburettors on a grey motor?” The carburettors that are the subject of this document are Bendix Stromberg (Australia) B-Model. I will focus in this document on the single-barrel Stromberg carburettors, as the twin-barrel W-Model Strombergs are more the domain of the HK/HT/HG/HQ Holden enthusiasts. I will particularly focus on the BXOV-1 Stromberg, as it was fitted to most early Holdens (FX, FJ, FE, FC, FB, EK, EJ). The Stromberg BXOV-1 carburettor was also fitted to American Austin Company (later reorganized as American Bantam) BRC ¼ ton U.S. Army American Bantams, and to model 77, 440, CJ-2A and CJ-3A Willys. Apparently the tooling for the BXOV-1 carburettor was sold to Holden after American Bantam was dissolved. Whilst most of the information will relate to the single barrel B-Model carburettors, I will include some W-Model information where it is ready at hand and helps either clarify or close-out an issue (for example, I have included below the Stromberg and Holden parts numbers for the HR Holden 186S engine WW Stromberg carburettors so that the list contains all factory carburettors for FX-HR Holdens). Whilst this document is primarily related to the FB and EK Holden carburettors, much of the information is similar or identical to other early Holdens. Please bear in mind that the early Holden carburettors are more than half a century old, and that limited documentation is known to exist other than references in parts and workshop manuals (despite much hunting by enthusiasts, and both FE/FC and FB/EK Clubs). Much of the information below is drawn from internet forums, discussion with enthusiasts and common sense. I have used photos and other information from a wide variety of sources, particularly from the forums – if anyone is offended by my use of the material, feels I have breached copyright or needs recognition, please let me know and I will correct the issue immediately. I would however like to thank the following for their patience and willingness to help me learn: Keith Hoffmann, Richi Morgan, Wayne Bradford, Matto and Alex Smits for fantastic access to some of the Workshop Manuals, Accelerator Magazines and accessory information. Fingers, Thommo and a bunch of other forum members for answering questions along the way. Stewart Watters, whose All Holden Day carburettor linkage photos I have pillaged. Equally, I have made opinions and drawn conclusions on some of the information I have found and equipment I have owned, and have cross-referenced a significant amount of printed material - if anyone believes that I have made an error (or knows a better way to do something), please let me know and I will update the document... after all, the main purpose here is to help other early Holden enthusiasts. I have marked some text in red in this document where I am missing information – any help in closing these gaps is appreciated. Like all things automotive, installing, operating and maintaining a carburettor comes with a risk. Leaking fuel lines can lead to fires, and items dropped down a carburettor throat can cause massive engine damage (amongst other hazards). Any advice contained in this document is to be taken at the reader‟s risk – qualified mechanics should be consulted where appropriate. 3 2 Not all Strombergs Are Equal… the Zenith Connection Stromberg carburettors were made by both Zenith and Bendix independently of each other, and are two very different pieces of equipment. Zenith Carburettors was a British company, which joined rival Solex Carburettors in 1955. Over time the Zenith brand name fell into disuse. The rights to the Zenith designs were owned by Solex UK (a daughter company of Solex in France). Zenith Stromberg carburettors were installed in Armstrong Siddeleys, Austins, Humbers, Jaguars, Land-Rovers, MGs, Saabs Sunbeams, Sunbeam Talbots, Triumphs and Volvos. The Zenith Stromberg carburettors are of “constant depression” design, where the venturi size changes depending on engine load (SU carburettors work on the same principle). A typical Zenith Stromberg carburettor is shown in the image to the right. Zenith Strombergs were fitted to LC Holden 161S GTR-XU1 161S engines (triple 1.5” 150 CDS side draught), LJ Holden 202 XU1 engines (triple 175 CD2-S side draught) and HB Holden Brabham Toranas (single 150 CD side draught). Holden also used carburettors from this company (though not Stromberg models) on the HB Holden 1200cc, LC and LJ Torana 1200cc and 1600cc and LJ Torana 1300cc engines (Zenith) and the LH and LX Torana 1900cc engines (Solex). I will not focus on the Zenith Stromberg carburettors in this document – the Torana guys are a much better source of information for these carburettors. The Bendix Corporation was an American manufacturing and engineering company which during various times in its sixty year existence (1924-1983) made brake systems, aeronautical hydraulics, avionics, radios, televisions and computers, and which licensed its name for use on home washing machines. Some history of the company is available at http://en.wikipedia.org/wiki/Bendix_Corporation. The Bendix Stromberg carburettors are of fixed venturi design, and are more typical equipment for early Holdens. A typical Bendix Stromberg B-Model carburettor is shown in the image to the right. Note that whilst early Holden B-Model Strombergs are no longer manufactured, Stromberg Carburetor Ltd, an English company, owns the Stromberg trademarks and is now remaking Stromberg E-Model carburettors (the traditional hotrodder‟s Stromberg 97). Parts from Stromberg Carburetor Ltd will be discussed further in this document I will refer to Bendix Strombergs carburettors as “Strombergs” for the remainder of this document. Single-barrel Stromberg carburettor were fitted to: 132.5ci FX, FJ, FE and FC Holden engines, 138ci, FB, EK, EJ Holden and LC and LJ Torana engines, 149ci EH and HD Holden engines, 161ci HR, HK, HT and HG Holden, LC, LJ, LH, LX and UC Torana and VB Commodore Holden engines (the LC 161S GTR engine used a two-barrel WW Stromberg), 173ci HQ and HJ Holden engines, 179ci EH and HD Holden engines (the HD X2 had twin single-barrel Strombergs), 186ci HR, HK, HT and HG Holden engines (the HR186S had twin singlebarrel Strombergs, and the 186ci (186S) HK, HT and HG Holden engines had twin-barrel WW Strombergs), 202ci HQ and HJ (low compression) and HJ, HX, HZ Holden, LJ, LH, LX and UC Torana and VB Commodore engines (HQ 202ci normal compression engines used a two-barrel Stromberg). The HG, HQ, HJ, HX HZ Holden, LH and LX Torana and VB Commodore 253ci engines used two-barrel WW Strombergs, completing the above list of Stromberg-equipped Holdens. 4 3 Decoding Stromberg carburettors have a Model number, a Code number and a Specification (for example for the EK Holden manual engines, these are BXOV-1, 23-3000 and 2375000 respectively). A given Model number (e.g. BXOV-1) may be used on many different types of vehicles (say Holdens and Willys). Bendix made several different Specifications for a given Model (for example the BXOV-1 had Specifications 380228, 2375000 and 2375002 – whilst visually similar, some items such as the jets change between different specifications). The Code number tells you what Model and Specification went to which manufacturer and vehicle (i.e. it‟s the link that tells you what car and engine combination a particular carburettor came from). 3.1 Stromberg Carburettor Model Numbers The following information gives the basis of the factory Stromberg Model numbers, though is valid for Stromberg carburettors produced after 1934. The Model number is sometimes, but not always cast into the throttle body. The first (and sometimes second) letter identifies the model. The Stromberg models are: o A (an aero-type 2-barrel downdraught) , E 4A W SF o B (a single barrel downdraught), o E (a 2-barrel downdraught), o OH (a single barrel horizontal), o SF (a side-float heavy duty single barrel updraught), o UC (a single barrel updraught), A B OH UC o W (a 2-barrel downdraught), and o 4A (a 4-barrel downdraught). A second letter identical to the first would denote a 2-barrel carburettor (e.g. WW is a 2-barrel series W carburettor). Early Holden Stromberg carburettors are normally B Models. Later model Holdens run WW Model Stromberg carburettors. The legendary “Stromberg 97‟s” beloved of hotrodders world-wide were originally EE Models, though there were 14 different 97‟s used in different vehicles. The letter(s) following the model designation have the following meanings: o B – a revision of AAV type (e.g. AAUVB), o D – built-in dashpot (e.g. BXVD). The dashpot retards the closing of the throttle, allowing the fuel charge to clear the manifold and prevent stalling when the accelerator is suddenly released, o E – electrically controlled dashpot (e.g. BXVES), o M – drain system incorporated (e.g. SFM), 1 o O – /8” oversize throttle barrel diameter (e.g. BXOV), o P – vacuum actuated accelerator pump (e.g. AAVP), o S – kickdown switch incorporated (e.g. AAVS). The kickdown switch allows the automatic transmission to shift down from fourth to third gear at speeds of less than 35-40mph, giving greater acceleration, 1 o U – /8” undersize throttle barrel diameter (e.g. BXUV), o V – vacuum controlled power system (e.g. BXV), and o X – cross flange (e.g. BXOV). A “cross flange” B model carburettor (BX…) has the flange bolts in 5 the same axis as the fuel inlet line, and at 90 to the throttle shaft. A “normal flange” B model o carburettor (B… - no X) has the flange bolts in the same axis as the throttle shaft, and at 90 to the fuel inlet line. The first number following the letters denotes the physical flange size of the carburettor and the throttle barrel size: 3 o 1 – S.A.E. nominal size 1” flange with throttle barrel diameter of 1 /16" and 3 2 /8” bolt spacing (often referred to as a “Size 1” flange) , 7 o 2 – S.A.E. nominal size 1¼” flange with throttle barrel diameter of 1 /16" and 11 2 /16” bolt spacing (often referred to as a “Size 2” flange), 11 15 o 3 – S.A.E. nominal size 1½” flange with throttle barrel diameter of 1 /16" and 2 /16” bolt spacing (often referred to as a “Size 3” flange), 15 5 o 4 – S.A.E. nominal size 1¾” flange with throttle barrel diameter of 1 /16” and 3 /16” bolt spacing (often referred to as a “Size 4” flange), and 2 9 o 5 – S.A.E. nominal size 2” flange with throttle barrel diameter of 2 /16” and 3 /16” bolt spacing (often referred to as a “Size 5” flange). Note that SF models carburettors do not follow the above convention. Note also that the “O” or “U” letters will change the above throttle barrel diameters away from standard. For some Strombergs there is a second number following the letters which denotes the automatic choke style: o 5 – electrically actuated automatic choke (e.g. BXOV-25) o 6 – hot air actuated automatic choke (e.g. BXOV-26) Finally, a third number following the letters (if present) denotes an integral Stromberg started switch: o 7 – Stromberg starter switch (i.e.AAUVB-167) So for 48, 53, FJ, FE, FC, FB, EK and EJ Holdens (BXOV-1) we have a single barrel downdraught 1 carburettor (B) with a cross flange (X), /8” oversize throttle (O) and vacuum controlled power system (V) 3 1 and an S.A.E. size 1 flange with barrel diameter of 1 /16” (1). Note though that the “O” indicates an /8” 3 1 5 oversize throttle, so the real throttle barrel diameter is (1 /16”+ /8” =) 1 /16”. For Bendix Stromberg carburettors made prior to 1935 or made in the USA, and for Zenith Strombergs carburettors, some further reference material is located here: http://www.thecarburettorshop.com/Carburettor_ID.htm#IDStromberg. Note that the above information gives a throttle barrel diameter, but does not give a venturi diameter (for example, the BXUV-2 carburettor fitted to the Holden HD 149ci economy (taxi) engines (late 1965 – April 1966) and Holden HR, HK 161ci economy (taxi) engines (April 1966 – 1968) had a venturi diameter of 1 1 /32”, whilst the BXUV-2 fitted to the Holden HD 179ci economy (taxi) engines (late 1965 – April 1966) 3 and Holden HR and HK 186ci economy (taxi) engines (April 1966 – 1968) had a different venturi of 1 /32” 5 diameter (both had 1 /16” diameter throttle barrels). o 3.2 Australian Stromberg Carburettor Codes The following are Stromberg carburettor codes for locally produced carburettors. The code numbers are stamped either on the air horn at the edge of the float chamber, on a metal tag (air horn reinforcing bar) attached to the air horn or stamped onto the main body casting below the edge of the float chamber (late Australian BX castings) – see diagram to the right. 6 The codes are interpreted as follows: The first section of numbers designates the make of vehicle. Letter(s) following the model designation have the following meanings: o 1 – Universal carburettor. o 2- Ford o 3 – Dodge o 4 – Chrysler o 6 – Studebaker o 7 – Buick o 15 - Plymouth o 16 – De Soto o 23 – General Motors Holden o 32 – International Harvester Company Note that US-made Strombergs use a different vehicle designation (see 3.3 below). US-made Stromberg carburettors used the number 23 for General Motors Truck and Coach Division (GMTC) rather than General Motors Holden. GMTC was originally the Yellow Coach bus manufacturer based in Chicago. GM purchased a controlling interest in Yellow Coach in 1925, and the remaining shares in 1943, renaming the company GMTC Division. GMTC Division manufactured interurban coaches until 1980 and transit buses until 1987. GM withdrew from the bus and coach market because of increased competition in the late 1980s. The second section of numbers refers to a particular carburettor specification. The letter suffix indicates an engineering change made to the specification (e.g. no letter is the first produced specification, an “A” indicates a major change to that specification, a “B” indicates a second major change etc). So for 48, 50, FJ, FE, FE and early FC Holdens (23-105D), we have a carburettor manufactured for General Motors Holden (23), with a specification of 380228 (105) which is at its fourth major engineering change (D). The table below lists the Stromberg carburettors made by Stromberg Australia for local vehicles. I have also included carburettors supplied by Stromberg USA to the local market, which are noted as such in the table. I have drawn the table above from a listing circulating on the Early Holdens forum together with listings from the Bendix Corporation (Australia) Carburettor and Fuel Pump Service Parts Catalogue (March 1968), from which I captured only Australian- or USA-built Stromberg carburettors. Some Australian delivered cars are likely to have UK-sourced Stromberg carburettors (variable venturi), which I have omitted. 7 Code 1-92CA 1-98C 1-3400 1-3401 2-3101 2-3102 2-3103 2-3104 2-3105 2-3106 2-3108 2-3109 2-3111 2-3112 2-3116 2-3117 2-3118 2-3119 2-3120 2-3123 2-3126 2-3127 2-3139 Model BXOV-2 BXUV-3 BXUV-3 BXUV-3 BV-2 BV-2 BV-2 BV-2 BV-2 BV-2 BV-2 BV-2 BV-2 BV-2 BOV-2 BV-2 BOV-2 BV-2 WW WW BOV-2 BV-2 unknown Specification A19102 A19103 2375006 2375011 2375022 2375023 2375022 2375023 2375022 2375023 2375033 2375034 2375037 2375038 2375046 2375047 2375048 2375049 2375053 2375054 2375075 2375076 unknown Vehicle Universal carburettor, 2 /16” flange bolt centres. Universal carburettor, 2 /16” flange bolt centres. Universal carburettor, 2 /16” flange bolt centres. Universal carburettor, 2 /16” flange bolt centres. Ford Falcon XR 170ci engines (1966 – 1967). Ford Falcon XR 200ci engines (1966 – 1967). Ford Falcon XR 170ci engines (1966 – 1967). Ford Falcon XR and 1967 Fairlane 200ci engines (1966 – 1967). Ford Falcon XR 170ci engines (1966 – 1967). Ford Falcon XR and 1967 Fairlane 200ci engines (1966 – 1967). Ford Falcon XT 188ci automatic transmissions (1968). Ford Falcon XT 221ci automatic transmissions (1968). Ford Falcon XT 188ci manual transmissions (1968). Ford Falcon XT 221ci manual transmissions (1968). Ford Falcon XW 221ci engines with manual and automatic transmissions (1969-1970). Ford Falcon XW 188ci engines with manual and automatic transmissions (1970). Ford Falcon XY 250ci engines with manual transmissions (1970). Ford Falcon XY 200ci engines with manual transmissions (1970). Ford 1970 XW Falcon and ZC Fairlane 302ci V8 engines with automatic transmissions; 1970-1971 Ford XY Falcon and ZD Fairlane 302ci V8 engines with manual and automatic transmissions. Ford 1970 XW 302ci engines with manual transmissions. Ford Falcon XY 250ci engines with automatic transmissions (1970) and ZD 250ci engine. Ford Falcon XY 200ci engines with automatic transmissions (1970). Ford XA 250ci engines with manual transmissions. 15 15 15 11 8 2-3147 2-3148 2-3154 2-3156 2-3163 2-3170 2-3171 2-3185 2-3190 2-3199 3-152 3-204A 3-211 3-215 3-224 3-226 3-241 3-259 3-273 4-3502 4-3503 6-123A unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown WW WW WW WW WW WW WW WW WW BXUV-3 BXUV-3 WW unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown 380441 381019 381026 381051 381060 381062 381092 381157 381193 2375012 2375012 380954 Ford 1973-1974 XB;TC-D 250ci engines with automatic transmissions. Ford TC-TD;XB 250ci engines with manual transmissions. Ford TC;XA;ZF 250ci engines with automatic transmissions. Ford XA; ZF 302ci V8 engines with manual and automatic transmissions. Ford 1975-1976 XB,TC-D 250ci engines with automatic transmissions. Ford XC 3.3L engines with manual transmissions. Ford XC 4.1L engines with automatic transmissions. Ford 1977 XC 4.1L engines with automatic transmissions. Ford XC 4.1L engines with automatic transmissions. Ford 1979 XD;TF 250ci engines with automatic transmissions. Dodge 960AV, 965AV, 990AV trucks with V8 engines (1958-1960). Note that this a Stromberg USA carburettor. Dodge AT4, AT5 and AT6 trucks with V8 engines (July – September 1962). Note that this a Stromberg USA carburettor. Dodge Phoenix SD2-M 1962. Note that this a Stromberg USA carburettor. Dodge AT4, AT5 and AT6 trucks with V8 engines (September 1962-1967). Note that this a Stromberg USA carburettor. Dodge Phoenix TD2-M 1963. Note that this a Stromberg USA carburettor. Dodge T series trucks with 313ci Canadian engines (late 1962-1967). Note that this a Stromberg USA carburettor. Dodge Phoenix VD-2 1964. Note that this a Stromberg USA carburettor. Dodge Phoenix DB6 1966. Note that this a Stromberg USA carburettor. Dodge Phoenix DC6 1967. Note that this a Stromberg USA carburettor. Valiant VC (6 cylinder) and 145hp VE engines (1967 - 1968). Valiant VC (6 cylinder) and 145hp VE engines (1967 - 1968). Studebaker Lark without positive crankcase ventilation (1959-1961). Note that this a Stromberg USA carburettor. 9 6-125 6-127 or 6-127A 6-128 or 6-128A 6-130 6-132 15-42A 23-105D 23-201A WW WW 381002 381028 Studebaker Lark without positive crankcase ventilation (1961). Note that this a Stromberg USA carburettor. Studebaker Lark without positive crankcase ventilation (1962). Note that this a Stromberg USA carburettor. Studebaker Lark with positive crankcase ventilation (1962). Note that this a Stromberg USA carburettor. Studebaker Lark with positive crankcase ventilation (1963-early 1964). Note that this a Stromberg USA carburettor. Studebaker Lark and Cruiser with positive crankcase ventilation (late 1964-1966). Note that this a Stromberg USA carburettor. Dodge PD44 V8 engines (1960). Note that this a Stromberg USA carburettor. Holden 48, 50, FJ, FE, FE and early FC (1948-1959). Holden HR, HK, HT and HG 186S engines with manual transmissions. Note that this a Stromberg USA carburettor. Holden HR, HK, HT and HG 186S engines with manual transmissions. Note that this a Stromberg USA carburettor. Holden HR, HK, HT and HG 186S engines with automatic transmissions. Note that this a Stromberg USA carburettor. Holden HR, HK, HT and HG 186S engines with automatic transmissions. Note that this a Stromberg USA carburettor. Holden HR, HK, HT and HG 186S engines with automatic transmissions. Note that this a Stromberg USA carburettor. Holden FC (late), FB, EK and EJ manual transmissions (1959 - 1963). Holden EK and EJ automatic transmissions (1961 - 1963). Holden EH 149ci engines (August 1963 - early 1964). Holden EH 179ci engines with manual and automatic transmissions (August 1963 – early 1964). Holden EH 149ci engines with manual and automatic transmissions (early 1964 - February 1965). WW WW WW WW BXOV-1 WW 381029 381067 381099 380971 380228 381205 23-201B 23-202 23-202A 23-202B 23-3000 23-3001 23-3002 23-3003 23-3005 WW WW WW WW BXOV-1 BXOV-1 BXUV-2 BXV-2 BXUV-2 381205 381206 381206 381206 2375000 2375002 2375003 2375005 2375007 10 23-3006 23-3007 23-3008 23-3009 23-3010 23-3011 23-3012 23-3013 BXV-2 BXUV-2 BXV-2 BXUV-2 BXUV-2 BXUV-2 BXUV-2 BXUV-2 2375008 2375009 2375010 2375013 2375014 2375017 2375018 2375009 Holden EH 179ci engines with manual and automatic transmissions (early 1964 – February 1965). Holden HD 149ci engines (February 1965 – April 1966). Holden HD 179ci engines (February 1965 – April 1966). Holden HD 179ci X2 engines front carburettor (February 1965 – April 1966). Holden HD 179ci X2 engines rear carburettor (February 1965 – April 1966). Holden HD 149ci economy (taxi) engines (late 1965 – April 1966). Holden HD 179ci economy (taxi) engines (late 1965 – April 1966). Holden HD (February 1965 - April 1966), HR and HK (April 1966 – 1968) automatic transmissions, HT, HG and LC 149ci and 161ci engines. Holden HD (February 1965 – April 1966), HR and HK (April 1966 – 1968), HT and HG 186ci engines with automatic transmissions. Holden HD (February 1965 – April 1966).179ci and HR (April 1966 – 1967) X2 engines with automatic transmissions front carburettor. Holden HD (February 1965 – April 1966).179ci and HR (April 1966 – 1967) X2 engines with automatic transmissions rear carburettor. Holden HR and HK (April 1966-1968), HT, HG and LC 161ci engines with manual transmissions. Holden HR and HK (April 1966 – 1968), HT and HG 186ci engines with manual transmissions. Holden HR and HK 186ci economy (taxi) engines (April 1966 – 1968). Holden HR, HK 161ci economy (taxi) engines (April 1966 – 1968). HR 186ci X2 engines with manual transmission rear carburettor (April 1966 – 1967). HR 186ci X2 engines with manual transmission front carburettor (April 1966 – 1967). Holden HT and HG 253ci V8 engines with automatic transmissions (1969/70). Holden HT and HG 253ci V8 engines with manual transmissions (1969-1970). Holden HT 186S engines with automatic transmissions (1969-1970). Holden HT and HG 186S engines with manual transmissions (1969-1970). Holden HG 186S engines with automatic transmissions (1970). Bedford 300ci 6 cylinder engines from 1970 and 1971 (single barrel). 23-3014 23-3015 23-3016 23-3019 23-3020 23-3021 23-3022 23-3023 23-3024 23-3032 23-3033 23-3034 23-3035 23-3036 23-3039 BXV-2 BXUV-2 BXUV-2 BXUV-2 BXUV-2 BXUV-2 BXUV-2 BXUV-2 BXUV-2 WW WW WW WW WW BXUV-3 2375010 2375013 2375014 2375024 2375025 2375018 2375017 2375027 2375027 2375039 2375040 2375043 2375044 2375050 2375057 11 23-3040 23-3041 23-3043 23-3044 23-3045 23-3046 23-3048 23-3050 23-3053 23-3054 23-3063 23-3064 23-3073 23-3074 23-3075 23-3076 23-3077 23-3078 23-3081 23-3082 23-3083 23-3084 23-3085 23-3086 23-3089 23-3090 23-3091 WW WW BXUV-2 BXUV-2 WW WW unknown unknown unknown unknown WW WW unknown unknown unknown unknown WW WW unknown unknown unknown unknown unknown WW unknown unknown unknown 2375058 2375060 2375061 unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown Holden late HT and all HG 253ci V8 engines with manual transmission. Holden LC GTR 161S (2600S) engines, from October 1969 to July 1971. Holden HT low compression 161ci engines with automatic transmissions, 1970 Holden HT low compression 161ci engines with manual transmissions, 1970 Holden HQ 253ci V8 engines from July 1971 to October 1972. Holden HQ 253ci V8 engines with manual transmissions (earlier carburettor). Holden LC 186S engines. Holden HQ, LC and LJ 173ci engines with manual transmissions. Holden HQ and LJ 202ci engines with automatic transmissions. Holden LC and LJ 138ci engines with manual transmissions. Holden HQ 253ci V8 engines with automatic transmissions from November 1972 to July 1973. Holden HQ 253ci V8 engines with manual transmissions (later carburettor, November 1972 onwards). Holden HQ 173ci engines with automatic transmissions. Holden HQ 173ci engines with manual transmissions. Holden HQ 202ci engines with automatic transmissions. Holden HQ 202ci engines with manual transmissions. Holden HQ 253ci V8 engines with automatic transmissions from August 1973 to September 1974. Holden HQ 253ci V8 engines with manual transmissions from August 1973 to September 1974. Holden LJ and LH Toranas, 173ci engines with automatic transmissions. Holden LJ and LH Toranas, 173ci engines with manual transmissions. Holden HJ and LJ and LH Toranas, 202ci engines with automatic transmissions. Holden HJ and LJ and LH Toranas, 202ci engines. Holden HJ and LH Torana, 253ci V8 engines with automatic transmissions. Holden HJ 253ci V8 engines with manual transmissions. Holden 1975 LH and LX Toranas, 173ci engines with manual transmissions. Holden 1975 LH and LX Toranas, 173ci engines with automatic transmissions. Holden 1975 LH and LX Toranas and HJ 202ci engines with manual transmissions. 12 23-3093 23-3094 23-3098 23-3099 23-3100 23-3101 23-3102 23-3103 23-3105 23-3106 23-3107 23-3109 23-3111 23-3112 23-3114 23-3115 23-3118 23-3120 32-3300 32-3301 32-3302 WW WW WW WW unknown unknown unknown unknown unknown unknown unknown unknown WW WW unknown unknown unknown unknown BXUV-3 BXUV-3 BXUV-3 unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown unknown 2375001 2375015 2375019 Holden HJ and LH and LX Toranas, 4.2L V8 engines with manual transmissions from January 1975 to June 1977. Holden HJ and LH and LX Toranas 4.2L V8 engines with automatic transmissions from January 1975 to June 1977. Holden HX and LX Torana 4.2L V8 engines with automatic transmissions from July 1976 to April 1977. Holden HX and LX Torana 253ci V8 engines with manual transmissions. Holden LX and UC Toranas, 173ci engines with automatic transmissions. Holden LX and UC Toranas, 173ci engines with manual transmissions. Holden HX and LX Torana, 202ci engine with automatic transmissions. Holden HX and LX Torana 202ci engine with manual transmissions. Holden HX and HZ 202ci engine with automatic transmissions (utility and panelvan). Holden HX and HZ 202ci engine with manual transmissions (exchange utility). Holden HX and HZ and LX Toranas, 202ci engine with manual transmissions. Holden HX and HZ 202ci engine with manual transmissions. Holden HX and HZ, LX Torana and VB Commodore 4.2L V8 engines with automatic transmissions from May 1977 to March 1980. Holden HX and HZ, LX Torana and VB Commodore 4.2 V8 engines with manual transmissions from May 1977 to March 1980. Holden HZ and LX and UC Toranas, 202ci engines with automatic transmissions. Holden HX and LX and UC Toranas, 202ci engines with manual transmissions. Holden VB Commodore 173ci engine with manual transmissions. Holden VB Commodore 202ci engine manual transmissions. International Harvester AB160, AB162, AB182, ABT182, AACO172, AACO182, AACO183 and AACOT182 (1962 – mid 1965), ABM160, ABM162 and ABM164 engines (late 1963 – mid 1965) International Harvester AB160, AB162, AB164, AB182, ABT182, AACO172, AACO182, AACO183, AACOT182, ABM160, ABM162 and ABM164 (mid-1965 – 1968). International Harvester AC1100, AC1200, AC1300, AC1500, AC1510, AC1600 and AC4X4 (late 1966 – 13 1968). 3.3 US Stromberg Carburettor Codes As noted above, US-made Stromberg carburettors do not use the same number designation for vehicle manufacturers as the Australian-made Strombergs (for the code numbers stamped either on the air horn at the edge of the float chamber, on a metal tag (air horn reinforcing bar) attached to the air horn). This make identification difficult if a carburettor has been sourced from the US. The following table indicates the USmade codes: No. 1 2 3 4 5 6 7 8 10 11 12 13 14 15 16 22 23 24 25 26 27 29 Manufacturer Standard carburettor Ford Dodge Chrysler Oldsmobile Studebaker Buick Nash Packard Lasalle Reo Pontiac Chevrolet Plymouth Desoto Hudson General Motors Truck and Coach Division Mack (International Motor Company) Wisconsin Motor Company Waukesha Motor Company Hercules Motor Company White Motor Company No. 31 32 34 35 39 40 41 49 51 60 64 66 70 71 82 83 88 89 92 96 97 99 Manufacturer Autocar Motor Truck Company International Harvester Company Continental Motor Corporation Buda Motor Company Universal Motor Company Lincoln Motor Car Company Lycoming Motor Manufacturing Company Brockway Motor Truck Company Climax Engineering Company Koehring The Corbitt Company Diamond T Company Available Truck Company Ahrens-Fox Federal Truck Harnischfeger Thew Shovel Company Byers Machine Company Fate-Root-Heath Company Willys-Overland Seagrave Company American LaFrance No. 106 108 109 121 124 128 130 133 135 147 149 153 165 185 205 213 219 256 265 266 Manufacturer Kenworth Truck Company Minneapolis-Moline Power Implement Company Twin Coach Company Clark Tractor Vulcan Iron Works Allis Chalmers LeRoi Motor Company Vaughan Motor Company Ward LaFrance Truck Whitcomb Locomotive Company Bucyrus-Erie Company Lima Locomotive Works Universal Crane Company Fairmont Railway Motor Company Cadillac Caterpillar Tractor Austin Manufacturing Company Flexible Company Checker Cab Kaiser-Frazer 14 4 Operation The Stromberg BXOV-1 carburettor has five basic systems that work together to provide the correct fuel/air mixture over different engine loads: The float system, which keeps a consistent level of liquid fuel “ready to go” in the carburettor, The idle system, which controls the fuel/air mixture at no-throttle and slight-throttle operation. The main metering system, which controls the fuel/air mixture at mid-throttle (or “cruise”) operation, The accelerating system, which adds a small “shot” of fuel when you initially put your foot down, The power system, which controls the fuel/air mixture at heavy throttle (hills, towing or race) operation. The choke system, which controls the air/fuel mixture for cold starting and warm-up. Each of these systems will be described below. Note that the BXV-2 and BXUV-2 carburettors fitted to EH, HD and HR Holdens operate identically. 4.1 BXOV-1 Main Components The following diagram shows the main components of the Stromberg BXOV-1 carburettor: 15 1. Venturi – increases the air velocity in the carburettor. 1A. Booster venturi – amplifies the vacuum applied to the main metering and power systems. 2. Accelerator pump discharge nozzle – sprays (atomises) fuel from accelerator pump shot. 3. Main discharge jet – mixes air and fuel and controls the combined quantity that is discharged from either the main metering system or the power system. 4. Float chamber vent – vents float chamber to atmosphere to keep mixtures set even if air cleaner fouls. 5. Choke valve – restricts air supply to provide a rich mixture for starting and warm-up. 6. High speed air bleeder – meters the air that is fed to the main metering system and the power system. st nd 7. Idle air bleed – meters the air that is fed into the idle system (both 1 and 2 stages). 7A. Idle tube – meters the fuel for the idle system (both 1 and 2 stages). 8. Vacuum power piston – opens up under heavy load (low manifold vacuum) to allow fuel to flow to the power system. 9. Accelerator pump – provides a “shot” of fuel when the accelerator is pressed down to enable smooth and rapid acceleration. 10. Float – maintains the fuel in the float chamber at a set level. 11. Float needle and seat – opened and closed by the float to allow fuel into the float chamber. 12. Throttle valve – controls the amount of fuel and air that is admitted into the intake manifold and hence sets the speed of the engine. 13. Idle discharge holes – discharges the fuel/air mixture from the idle system. st 14. Idle needle valve – controls the quantity of fuel/air mixture that is discharged from the 1 stage idle system. 15. Main metering jet – meters the fuel that is delivered by the main metering system during “cruise” operation. 16. Power bypass jet – meters the fuel that is delivered by the power system during high speed or heavy load operation. 17. Accelerator pump bypass jet – acts as a non-return valve to prevent the accelerator pump drawing in air as it recharges, and determines the rate that the fuel “shot” is delivered to the carburettor. 18. Accelerator pump check valve – admits fuel from the float bowl into the accelerator pump when it is recharging, and prevents fuel flowing back again when the accelerator pump is discharging. st nd 16 4.2 BXUV-2 and BXV-2 Main Components The following diagram shows the main components of the Stromberg BXOV-1 carburettor: Note that this is identical to the diagram in Section 4.1 above, with the following additions: 14A. Restrictor Wire – reduces the cross-sectional area of the idle passage to assist hot starting. 19. Vent valve – vents the float bowl to atmosphere under idle conditions to assist hot starting. 17 4.3 Float System Fuel from the fuel tank is fed via the fuel pump to the carburettor. If the fuel level is too low, the float (basically a hollow brass ball that floats on the fuel in the float chamber) drops down and opens the float needle valve. This allows the pressurised fuel to enter the carburettor and begin filling the float chamber. Once the fuel level is high enough, the float rises, and closes off the float needle valve. The float chamber is vented by an internal passage to the air horn. This balanced pressure ensures that fuel/air mixtures stay constant even if the air filter is blocked by dirt. 4.4 Idle System Under very low engine speeds (idling), the engine does not produce enough vacuum to suck sufficient fuel from the main metering system (due to the near-closed throttle plate). However, under the throttle plate a high vacuum exists. This vacuum is used to pull fuel from the idle system. The idle system has a first and second stage. The diagram below to the left shows the first stage operating, whilst the diagram to the right shows the second stage operating. When the engine is idling (first stage or foot fully off the accelerator), the throttle valve is held open very slightly by the slow idle adjusting screw. By turning the screw, the throttle plate can be opened, letting more fuel and air into the engine and increasing the idle speed. With the throttle plate pretty much closed, almost all the vacuum created by the pistons moving downward (“manifold vacuum”) is concentrated on the lower idle discharge hole under the throttle valve. This “sucks” the fuel from the float bowl, past the main metering jet and through the idle tube. The idle tube has a very small “metering orifice” or hole in the end which meters the amount of fuel. Even though the fuel is flowing through both the idle tube and the main metering jet, the idle tube does most of the metering (or controlling) of the fuel flow. This is because the idle tube metering orifice is about half the diameter of the main metering jet (much more restrictive). From the idle tube the fuel is sucked through a connecting passage and past the idle air bleed. The idle air bleed mixes in air to form an emulsion, which then keeps passing through the passage and then flows out of the lower idle discharge hole. The amount of fuel/air mixture which passes is regulated by the idle needle valve – screwing it in lets less fuel/air emulsion flow (leaner), screwing it out lets more fuel/air emulsion flow (richer). The idle air bleed also acts as a vent to prevent siphoning of fuel from the idle system at high speeds or when the engine is shut off. 18 The second idle stage comes into play as the throttle starts to open (initial take off from start). As the throttle valve opens, the upper two idle discharge holes are uncovered, and the manifold vacuum can then begin to draw (or “suck”) fuel from them. Note that although the upper two and lower idle discharge holes take fuel/air emulsion from the same place, the idle needle valve only change the operation of the st lower idle discharge hole (1 stage). 4.5 Main Metering System As the throttle is opened more, the manifold vacuum is able to act on the main metering system. Fuel is sucked from the float chamber through the main metering jet. The size of the hole in the main metering jet determines how much fuel can flow. The fuel then flows to the base of the main discharge jet. The fuel flows through two drillings in the lower squared section of the jet, then up the jet annular. As it flows it passes the high speed air bleed, which mixes in air to form an emulsion. The emulsion then passes out the main discharge jet. The main discharge jet also plays a critical role in setting the mixture. Normally, as the air flows through the carburettor, the proportion of fuel drawn from the main metering system would increase due to the petrol becoming more volatile under reduced pressure. This would mean that as engine speed increased, the mixture would get overly rich at cruise conditions. To prevent this, the main discharge jet has a series of internal air holes. The holes allow the air from the high speed bleeder to mix in. At low engine speeds, the low venturi suction allows the liquid level inside the main jet (coloured red in the diagrams below) to sit high in the jet (the diagram to the left). This blocks off a lot of the air holes, reducing the amount of air getting into the fuel mixture. As engine speed increases, the increased venturi 19 suction makes the fuel level drop down in the jet (the diagram to the right). This uncovers more of the air holes, letting more air get into the fuel mixture so that the mixture remains constant. The dome shaped high-speed air bleed also condenses any fuel vapour that forms in a hot carburettor after engine shutdown, helping to prevent fuel percolation (boiling). The main discharge jet is located inside a booster venturi. This is a small venturi inside the main venturi, which helps to increase the vacuum signal (or “suck”) seen by the main metering system. Using a booster venturi means that the carburettor delivers good low-speed throttle response without having to use a smaller (restrictive) main venturi. Whilst the idle system is still in operation when the main metering system is running, the amount of fuel it delivers is far less than the main metering system at “cruise” conditions. 4.6 Accelerating System To allow smooth acceleration when the accelerator pedal is first pushed down, an extra “shot” of fuel is needed. The accelerator pump is a piston pump which is mechanically connected to the throttle. When the throttle is pushed down, the connections drive the accelerator pump piston down, forcing fuel past the pump bypass jet. The pump check valve assembly closes to stop fuel flowing backwards into the float bowl. The restriction of the accelerator pump bypass jet causes the accelerator pump spring to compress as the piston is slowed down. The pump is a positive displacement unit and pumps the same volume regardless of the jet size – the jet just determines how fast the “shot” is released. Fuel flows through a passage to the accelerator pump discharge nozzle. The nozzle atomises the fuel before it is sprayed into the carburettor (as the accelerator system has no air bleed to make an emulsion). As the throttle is released, the accelerator pump piston is drawn back 20 upwards. The accelerator pump bypass jet closes to stop air being sucked in from the carburettor, and the pump check valve opens to allow fuel to refill the pump from the float chamber, ready for the next “shot”. Note that the chamber immediately surrounding the pump discharge nozzle is vented through the float chamber vent tube to prevent fuel being drawn from the pump circuit at high engine speeds by the high venturi vacuum. 4.7 Power System When running under heavy load (high speed, towing, travelling up hills or racing), a richer mixture is required. The power system utilizes a small piston which is normally help “up” by manifold vacuum. The piston is balanced (one side sees manifold pressure and the other sees air horn pressure – see red vacuum channels in the diagram to the right), with a spring trying to push the piston down. Under heavy load conditions the manifold pressure drops to 4-6” Hg (2-3psi), and the vacuum power piston is released downwards to push on the power bypass jet stem. This allows fuel to flow from the float chamber through the power bypass jet, up the main discharge jet (mixing with air from the high speed bleed) and out the main discharge jet. This process “bypasses”, or adds fuel in addition to, the main metering jet (i.e. under heavy load both the main metering system and the power system are operational). 4.8 Choke System Whilst BX-Model carburettors were fitted with either manual, electric or hot-air chokes, early Holden singlebarrel Strombergs are all fitted with manual chokes. When starting a cold engine, a richer than normal mixture is required (because the slowly-spinning engine produces little vacuum to draw out fuel, and much of the fuel condenses on the cold inlet manifold walls). To do this, the choke valve is shut, restricting air into the carburettor. The choke valve is connected by a mechanical linkage (the fast idle cam) to the throttle valve . When the choke valve is shut, the throttle valve is cracked open. When the choke is opened, the throttle returns to its normal position. The choke valve has a light spring, which provides some “slop” in the choke plate. The “slop” allows the choke valve to open slightly once the engine fires. The choke valve is also fitted with a spring-loaded poppet valve. When the engine starts, if the choke plate is jammed shut (choke lever pulled all 21 the way out), the increased vacuum opens the poppet valve, relieving some of the suction on the idle system and preventing flooding. A light buzzing noise from the poppet valve washer can be heard if the engine is being overchoked in this fashion. 4.9 Spacer Early Holdens used a spacer (often referred to as a phenolic or Bakelite spacer, or heat insulator) between the carburettor and inlet manifold. The purpose of this spacer was to prevent heat soaking from the inlet manifold into the carburettor, causing percolation (fuel boiling) and poor fuel flow. When vehicles are fitted with extractors, the spacer may be able to be removed, as the heat-sink into the inlet manifold is considerably less. 22 5 Early Holden Stromberg Factory Specifications I have drawn the table below by cross-referencing the following sources: The Bendix Corporation Australia (Automotive) Pty Ltd Stromberg Carburettor Service Manual No. BM1 issued August 1968, together with the Stromberg Service Manual Supplement issued November 1970 (Part No. SM1). The Bendix Corporation Australia (Automotive) Pty Ltd Carburettor & Fuel Pump Service Parts Catalogue No. PC2 Issued March 1968. The Holden Workshop Manual (48/215 Manual) The Holden FJ Workshop Manual The Holden FE and FC Workshop Manual. The Holden EK Workshop Manual. The Holden „FB‟ Workshop Manual. The Holden „EJ‟ „EH‟ Workshop Manual. The Holden HD Workshop Manual. The Holden HR Workshop Manual. The Master Parts Catalogue (20 Years of Holden Production). The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR. The Scientific Publications Workshop Manual Series No. 86 Holden covering series HK, HT, HG (whilst this document does not aim to examine HK/HT/HG Holdens, the HR, HK, HT and HG Holden 186S engines have identical WW Stromberg carburettors). I have used the Bendix Corporation Australia (Automotive) Pty Ltd Stromberg Carburettor Service Manual No. BM1 issued August 1968 as the starting point of the table, as it appears to be the most comprehensive and complete table available. I have added additional information from the above references, and have added notes throughout the table where that information is contradictory to the Bendix Corporation Australia (Automotive) Pty Ltd Stromberg Carburettor Service Manual No. BM1 issued August 1968. 23 Vehicle (NOTE 1) Holden 48, 50, FJ, FE, FE and early FC (1948-1959). Holden FC (late), FB, EK and EJ manual transmissions (1959 - 1963). Holden EK and EJ automatic transmissions (1961 - 1963). Holden EH 149ci engines (August 1963 - early 1964). Holden EH 149ci engines with manual and automatic transmissions (early 1964 February 1965). Holden EH 179ci engines with manual and automatic transmissions (August 1963 – early 1964). Holden EH 179ci engines with manual and automatic transmissions (early 1964 – February 1965). Holden HD 149ci economy (taxi) engines (late 1965 – April 1966) and Holden HR, HK 161ci economy (taxi) engines (April 1966 – 1968). Holden HD 179ci economy (taxi) engines (late 1965 – April 1966) and Holden HR and HK 186ci economy (taxi) engines (April 1966 – 1968). Stamping 23-105D 23-3000 23-3001 23-3002 23-3005 23-3003 23-3006 23-3011 and 233022 BXUV-2 Model BXOV-1 380228 2375000 2375002 3 SAE 1” size cross flange with 2 /8” bolt spacing 1 /32” 1 /16” 0.051” (NOTE 2) 5 1 BXUV-2 2375003 BXV-2 Specification Flange size Main venturi diameter Throttle bore 2375007 2375005 2375008 2375017 11 SAE 1¼” size cross flange with 2 /16” bolt spacing 1 /32” 3 23-3012 and 233021 BXUV-2 (NOTE 44) 2375018 1 /32” 1 /16” 7 5 1 /32” 3 1 /32” (NOTE 45) 5 1 /16” 0.051” (NOTE 6) 0.055” (NOTE 7) 1 Main metering jet 0.055” (NOTE 3) 0.059” (NOTE 4) (NOTE 5) Main discharge jet (NOTE 8) High speed bleeder 28-34 (NOTE 57) 28-30 28-30 #70 drill (0.0280”) (NOTE 10) 0.059” (0.058” fitted from August 1964) (NOTE 5) 28-36 (NOTE 9) #68 drill (0.0310”) (NOTE 13) 28-30 #68 drill (0.0310”) (NOTE 15) #53 drill #52 drill (0.0595”) (0.0635”) (NOTE (NOTE 19) 20) #56-64-70 drill (0.0465#70 drill (0.0280”) (NOTE 14) Idle tube #70 drill (0.0280”). #70 drill (0.0280”) (NOTE 11) #52 drill (0.0635”) (NOTE 16) #68 drill (0.0310”) (NOTE 12) #53 drill (0.0595”) (NOTE 17) #70 drill (0.0280”) Idle air bleed #52 drill (0.0635”) 0.054” (NOTE 18) #56-58 drill (0.0465- Idle discharge holes #56-64-70 drill (0.0465-0.0360-0.0280”) 24 Idle screw setting 7 /8 turn out #65 drill (0.0350”) (NOTE 21) #56 drill (0.0465”) (NOTE 22) #56 drill (0.0465”) 0.0420”) 1 turn out #55 drill (0.0520”) (NOTE 23) 0.0360-0.0280”) #65 drill (0.0350”) (NOTE 24) #56 drill (0.0465”) (NOTE 25) Power bypass jet #67 drill (0.0320”) (NOTE 21) Pump bypass jet Pump discharge jet Pump capacity per stroke Float needle seat orifice diameter (NOTE 26) Float bench setting Fuel level at 3psi (NOTE 28) Pump link setting Pump stroke – bench setting Pump stroke – vehicle setting (NOTE 29) Vent valve lift (NOTE 32) 17 13 15 #70 drill (0.0280”) 0.070” 0.83cc 0.073” (NOTE 27) 0.073” 1 5 #72 drill (0.0250”) 0.5-0.8cc 0.092” /8- /16” Middle 7 5 0.073” 0.092” /8” 11 /64- /64” /32- /64” (NOTE 30) 15 5 19 /32- /64” 5 19 /64- /64” (NOTE 58) Holden HD (February 1965 – April 1966) 179ci engines, Holden HD 179ci X2 engines front carburettor (February 1965 – April 1966) and HR (April 1966 – 1967) X2 engines with automatic transmissions front carburettor Holden HD (February 1965 – April 1966) 179ci, Holden HD 179ci X2 engines rear carburettor (February 1965 – April 1966) and HR (April 1966 – 1967) X2 engines with automatic transmission s rear carburettor. /16- /64” (NOTE 31) 17 /32- /64” (NOTE 46) 15 0.040-0.060” 0.040-0.060” (NOTE 47) Vehicle (NOTE 1) Holden HD (February 1965 - April 1966), HR and HK (April 1966 – 1968) automatic transmissions, HT, HG and LC 149ci and 161ci engines. Holden HD 179ci engines (February 1965 – April 1966). Holden HD (February 1965 – April 1966), HR and HK (April 1966 – 1968), HT and HG 186ci engines with automatic transmissions. Holden HR and HK (April 19661968), HT, HG and LC 161ci engines with manual transmissions. Holden HR and HK (April 1966 – 1968), HT and HG 186ci engines with manual transmissions. HR 186ci X2 engines with manual transmission front carburettor (April 1966 – 1967). HR 186ci X2 engines with manual transmission rear carburettor (April 1966 – 1967) Holden HR, HK, HT and HG 186S engines with manual transmissions. Holden HR, HK, HT and HG 186S engines with automatic transmissions. Stamping 23-3013 and 23-3007 BXUV-2 23-3008 and 233014 BXV-2 23-3009 and 233015 23-3010 and 233016 23-3023 23-3019 BXUV-2 23-3020 BXV2 23-3024 BXUV-2 (NOTE 52) 23-201A and 23201B Model BXUV-2 (NOTE 48) 23-202, 23-202A and 23202B WW (NOTE 52) 25 Specification Flange size Main venturi diameter Throttle bore diameter Main metering jet (NOTE 51) Main discharge jet (NOTE 8) (NOTE 51) High speed bleeder Idle tube 2375009 1 /32” 1 /16” 0.055” (NOTE 6) 5 3 2375010 1 /32” 1 /16” 0.058” (NOTE 50) 7 5 2375013 2375014 2375024 2375025 11 SAE 1¼ size cross flange with 2 /16” bolt spacing 3 5 1 /32” 1 /32” 1 /16” 0.055” 28-30 #70 drill (0.0280”) 0.055” (NOTE 33) 5 2375027 3 5 2375028 1 /32” 1 /16” 0.055” 0.055” 381205 381206 Four-bolt 28 1 /32” 1 /16” 0.053” (NOTE 35) #36 drill 7 1 /16” 0.058” (NOTE 34) 7 #68 drill (0.0310”) #70 drill (0.0280”) #53 drill (0.0595”) (NOTE 37) #68 drill (0.0310”) #70 drill (0.0280”) (NOTE 56) #53 drill (0.0595”) (NOTE 38) Idle air bleed #53 drill (0.0595”) #56-64-70 drill (0.04650.03600.0280”) #56 drill (0.0465”) (Note 59) 0.054” #53 drill (0.0595”) 0.054” #70 drill (0.0280”) (NOTE 36) #40 drill (main body – 0.0980”) #50 drill (air horn – 0.0700”) (NOTE 39) #50-54 drill (0.07000.0550”) (NOTE 40) 1.5 turns out Idle discharge holes #56-58 drill (0.04650.0420”) #56-64-70 drill (0.0465-0.03600.0280”) 1 turn out #56 drill (0.0465”) #56 drill (0.0465”) (NOTE 41) #56 drill (0.0465”) #72 drill (0.0250”) 0.5-0.8cc #56-58 drill (0.04650.0420”) #56-64-70 drill (0.04650.0360-0.0280”) Idle screw setting Power bypass jet (NOTE 51) Pump bypass jet Pump discharge jet (NOTE 51) Pump capacity per stroke Float needle seat orifice diameter (NOTE 26) Float bench setting Fuel level at 3psi (NOTE 28) #55 drill (0.0520”) #55 drill (0.0520”) #56 drill (0.0465”) #56 drill (0.0465”) (NOTE 42) #68 drill nozzle (0.0310”) (NOTE 43) - 0.073” 0.092” (NOTE 49) 0.092” 1 5 0.073” /8” 0.092” (NOTE 53) 0.101” 3 5 /16” /8- /16” 11 /8”@3¼ psi 26 Pump link setting Pump stroke – bench setting Pump stroke – vehicle setting (NOTE 29) Vent valve lift (NOTE 32) Wide open kick setting Vacuum kick setting Thermostat adjustment Dashpot setting Fast idle speed and cam position setting Accelerator pump stroke and external vent setting Choke modulation spring setting Thermostat lever position setting Middle 7 /32- /64” 5 19 /32- /64” (NOTE 46) 5 15 /16- /64” 5 15 /32- /64” (NOTE (NOTE 46) 46) 0.040-0.060” (NOTE 47) 3 17 /32- /64” (NOTE 54) 15 /32- /64” /32- /64” 17 /16- /64” 5 15 /32- /64” (NOTE (NOTE 54) 54) 0.040-0.060” (NOTE 55) 3 9 7 7 19 7 19 - /32” /32” 3 #69 Dead Centre 1 /16- /32” 7 - #15 drill (0.1800”), 3 /8 turn +/-0.015” +/-0.010” 1 /32” 3 NOTE 1: The Master Parts Catalogue (20 Years of Holden Production) lists the different Specifications as Carburettor Assemblies. The split of which Specification (Assembly) goes to which vehicle is slightly different to the Stromberg Carburettor Service Manual No. BM1 issued August 1968 and the Bendix Corporation Australia (Automotive) Pty Ltd Carburettor & Fuel Pump Service Parts Catalogue No. PC2 Issued March 1968 values used in the first row of the table above. The Specifications (Assemblies) listed in the Master Parts Catalogue (20 Years of Holden Production) which conflict with the above are as follows: Carburettor assembly 48, 50, FJ 7402765 Carburettor assembly FE, FC, FB, EK (manual), EJ (manual) 7412264 Carburettor assembly EK (automatic), EJ (automatic) 7418661 Carburettor assembly EH 149 engine, HD 149 engine, HR (automatic) 161 engine 7426784 Carburettor assembly EH 179 engine, HD 179 (excluding X2) engine, HR (automatic) 186 (excluding X2 and S) engine 7426904 Carburettor assembly HD 149 engine, HR 161 engine economy carburettors 7430100 Carburettor assembly HD 179 (excluding X2), HR 186 (excluding X2 and S) engine economy carburettors 7430107 Carburettor assembly - front HD X2 engine, HR (automatic) X2 engine 7428498 Carburettor assembly – rear HD X2 engine, HR (automatic) X2 engine 7428502 27 NOTE 2: NOTE 3: NOTE 4: NOTE 5: NOTE 6: NOTE 7: NOTE 8: The Master Parts Catalogue (20 Years of Holden Production) lists both 0.050” and 0.051” main metering jets for 48, 50 and FJ Holdens. The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR lists a 0.050” main metering jet for 1948/53 Holdens. The Holden FJ Workshop Manual lists a 0.051” main metering jet for all FJ Holdens. The Holden „EJ‟ „EH‟ Workshop Manual lists 0.057” main metering jets for EH Holden 149ci engines. The Master Parts Catalogue (20 Years of Holden Production) lists 0.051”, 0.053” and 0.055” main metering jets for EH Holden 149ci engines. The Holden „EJ‟ „EH‟ Workshop Manual lists 0.058” main metering jets for EH Holden 179ci engines, as does the Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR. The Master Parts Catalogue (20 Years of Holden Production) lists 0.055”, 0.057”, 0.058” and 0.059” main metering jets for EH Holden 179ci engines. The Holden Workshop Manual (48/215 Manual) indicates that three combinations of main metering jets were used in production:“A” – early production, distinguished by one red paint dot on the float chamber cover (0.050”), “B” – intermediate production, distinguished by two green paint dots on the float chamber cover (0.050”), and “C” – late production, no distinguishing marks (No. 0.051”). Individual parts of early, intermediate or late production jet combinations must not be mixed. The carburettor repair kit serviced by “NASCO” contains a complete jet combination and this kit must be used to service all carburettors. When carburettors are services and the setting is changed, the distinguishing marks on the top of the float chamber cover must be altered to agree with the specifications above. The Master Parts Catalogue (20 Years of Holden Production) lists 0.055” main metering jets for HD Holden 149ci (non-economy) engines, as does the Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR. The Holden HD Workshop Manual lists a 0.055” main metering jets for all HD Holden 149ci engines, with a 0.053” main metering jet for 4,000-8,000ft and a 0.051” main metering jet for 8,000-12,000ft high altitude operation. The Master Parts Catalogue (20 Years of Holden Production) lists 0.058” and 0.059” main metering jets for HD Holden 179ci (excluding X2) non-economy engines. The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR lists a 0.058” main metering jet for all HD Holden 179ci and HR Holden 186ci engines. I have listed in the table the values for main discharge jet numbers given in the Holden EK Workshop Manual, the Holden „FB‟ Workshop Manual, The Holden „EJ‟ „EH‟ Workshop Manual, the Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR and the Scientific Publications Workshop Manual Series No. 86 Holden covering series HK, HT, HG. The Bendix Corporation Australia (Automotive) Pty Ltd Carburettor & Fuel Pump Service Parts Catalogue No. PC2 Issued March 1968) indicates a single main discharge jet for all these carburettors (not the multiple values given above), but does not indicate its size. The Holden Workshop Manual (48/215 Manual) indicates that three combinations of main discharge jets were used in production:“A” – early production, distinguished by one red paint dot on the float chamber cover (No. 28-34), “B” – intermediate production, distinguished by two green paint dots on the float chamber cover (No. 28-30), and “C” – late production, no distinguishing marks (No. 28-30). 28 NOTE 9: NOTE 10: NOTE 11: NOTE 12: NOTE 13: NOTE 14: NOTE 15: NOTE 16: NOTE 17: NOTE 18: NOTE 19: NOTE 20: NOTE 21: Individual parts of early, intermediate or late production jet combinations must not be mixed. The carburettor repair kit serviced by “NASCO” contains a complete jet combination and this kit must be used to service all carburettors. When carburettors are services and the setting is changed, the distinguishing marks on the top of the float chamber cover must be altered to agree with the specifications above. The Master Parts Catalogue (20 Years of Holden Production) lists all EH Holdens as having a 28-30 main discharge jet, as does the Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR. The Holden „EJ‟ „EH‟ Workshop Manual lists a Nº.68 drill (0.0310”) high speed bleeder for EH Holden 179ci engines. The Holden „EJ‟ „EH‟ Workshop Manual lists a Nº.70 drill (0.0280”) idle tube for EH Holden 149ci engines. The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR lists a Nº.68 drill (0.0310”) for all EH Holden engines. The Bendix Corporation Australia (Automotive) Pty Ltd Carburettor & Fuel Pump Service Parts Catalogue No. PC2 Issued March 1968 indicates a Nº.70 drill (0.0280”) idle tube for Holden EH 149ci engines with manual and automatic transmissions (early 1964 February 1965), with a Nº.68 drill (0.0310) used from August 1964. The Holden „EJ‟ „EH‟ Workshop Manual lists a Nº.70 drill (0.0280”) idle tube for EH Holden 149ci engines. The Bendix Corporation Australia (Automotive) Pty Ltd Carburettor & Fuel Pump Service Parts Catalogue No. PC2 Issued March 1968 indicates a Nº.70 drill (0.0280”) idle tube for Holden EH 179ci engines with manual and automatic transmissions (early 1964 – February 1965). The Holden „EJ‟ „EH‟ Workshop Manual lists a Nº.70 drill (0.0280”) idle tube for EH Holden 179ci engines. The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR lists a Nº.68 drill (0.0310”) for all HD and HR Holden engines. The Holden HD Workshop Manual lists a Nº.68 drill (0.0310”) for all HD Holden engines. The Bendix Corporation Australia (Automotive) Pty Ltd Carburettor & Fuel Pump Service Parts Catalogue No. PC2 Issued March 1968 indicates a Nº.70 drill (0.0280”) idle tube for Holden HD 179ci economy (taxi) engines (late 1965 – April 1966) and Holden HR and HK 186ci economy (taxi) engines (April 1966 – 1968). The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR lists a Nº.53 drill (0.0310”) idle air bleed for all EH Holden 149ci engines. The Holden „EJ‟ „EH‟ Workshop Manual lists a Nº.52 drill (0.0635”) idle air bleed for EH Holden 149ci engines. The Holden „EJ‟ „EH‟ Workshop Manual lists a Nº.50 drill (0.070”) idle air bleed for EH Holden 179ci engines. The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR lists a Nº.53 drill (0.0595”) for all HD Holden 149ci and HR Holden 161ci engines. The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR lists a 0.054” idle air bleed for all HD Holden 179ci and HR Holden 186ci engines (excluding X2 engines). The Master Parts Catalogue (20 Years of Holden Production) indicates that 48/50/FJ/FE/FC/FB/EK/EJ all share same power bypass jet assembly but does not list the size. The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR lists a Nº.63 drill power bypass jet (0.0370”) for 1948/53 Holdens, Nº.67 drill (0.0320”) for FJ, FE and FC Holdens and a Nº.65 drill (0.0350”) for FB, EK and EJ Holdens. The Holden FE and FC Workshop Manual lists a Nº.67 29 NOTE 22: NOTE 23: NOTE 24: NOTE 25: NOTE 26: NOTE 27: NOTE 28: drill (0.0320”) power bypass jet for all FE and FC Holdens. The Holden FJ Workshop Manual lists a No. 67 drill (0.0320”) power bypass jet for all FJ Holdens. The Holden „EJ‟ „EH‟ Workshop Manual lists a Nº.57 drill (0.0430”) power bypass jet for EH Holden 149ci engines. The Master Parts Catalogue (20 Years of Holden Production) lists both a Nº.57 drill (0.0430”) and Nº.56 drill (0.0465”) power bypass jets for EH Holden 149ci engines. The Holden „EJ‟ „EH‟ Workshop Manual lists a Nº.54 drill (0.0550”) power bypass jet for EH Holden 179ci engines. The Master Parts Catalogue (20 Years of Holden Production) lists both Nº.55 drill (0.0520”) and Nº.54 drill (0.0550”) power bypass jets for EH Holden 179ci engines. The Master Parts Catalogue (20 Years of Holden Production) lists a Nº.56 drill (0.0465”) power bypass jet for HD Holden 149ci noneconomy engines and a Nº.65 drill (0.0350”) for economy engines. The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR lists a Nº.56 drill (0.0465”) power bypass jet for all HD Holden 149ci and HR Holden 161ci engines. The Holden HD Workshop Manual lists a Nº.56 drill (0.0465”) power bypass jet for all HD Holden 149ci engines The Master Parts Catalogue (20 Years of Holden Production) lists a Nº.65 drill (0.0350”) power bypass jet for non-economy HD Holden 179ci and non-economy HR Holden 186ci engines and a Nº.56 drill (0.0465”) for the economy versions of both engines. The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR lists a Nº.55 drill (0.0520”) power bypass jet for all HD Holden 179ci and HR Holden 186ci engines. The Master Parts Catalogue (20 Years of Holden Production) lists float needle valve and seat assemblies which imply different sizes for some vehicle to those specified in the Holden EK Workshop Manual, Holden „FB‟ Workshop Manual and Holden „EJ‟ „EH‟ Workshop Manual values used in the table above. The float needle valve and seat assemblies specified in the Master Parts Catalogue (20 Years of Holden Production) are as follows: Float needle valve and seat assembly 48, 50, FJ 7405155 Float needle valve and seat assembly FE, FC, FB, EK, EJ, EH, HD, HR (excluding S engine) 7406701 Float needle valve and seat assembly – heavy duty FE, FC, FB, EK, EJ, EH, HD, HR (excluding S engine) 7420335 Float needle valve and seat assembly HR S engine VS10443 The Bendix Corporation Australia (Automotive) Pty Ltd Carburettor & Fuel Pump Service Parts Catalogue No. PC2 Issued March 1968 indicates a 0.073” float needle and seat diameter (with an optional 0.079” heavy duty unit) for all the above vehicles with the exception of Holden 48, 50, FJ, FE, FE and early FC (1948-1959), which it lists as 0.070”. The Holden FB, Holden EK and Holden „EJ‟ „EH‟ Workshop Manuals list 0.073” for these cars, as does the Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR (it also lists 0.070” for late FC Holden).The Holden FE and FC Workshop Manual lists a 0.070” orifice. The Stromberg Carburettor Service Manual No. BM1 issued August 1968 indicates fuel level at 3psi for B-series and 3¼ psi for WW models, and are the values tabulated above. The Holden Workshop Manual (48/215 Manual), Holden FJ Workshop Manual, Holden FE and FC Workshop Manual, Holden EK Workshop Manual, Holden FB Workshop Manual and „EJ‟ „EH‟ Workshop Manual (EJ motor section) both lists the same values at 4psi. The „EJ‟ „EH‟ Workshop Manual (EH motor section) lists the fuel level for 179ci 30 NOTE 29: NOTE 30: NOTE 31: NOTE 32: NOTE 33: NOTE 34: NOTE 35: NOTE 36: NOTE 37: engines as /64- /16” at 3psi. The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, 5 FC, FB, EK, EJ, EH, HD, HR gives the single value of /8” at idling. I have given the values for accelerator pump stroke from the Stromberg Carburettor Service Manual No. BM1 issued August 1968. The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR gives the following values: 1948/53 Holden 0.297” maximum FJ/FE/FC Holden 0.281” +0.015” -0.024” FB/EK/EJ Holden 0.281” +0.015” – 0.024” EH/HD/HR Holdens 0.250” +/-0.030” 3 7 The Holden „EJ‟ „EH‟ Workshop Manual indicates a pump stroke setting of /16- /32” for EH Holden 149ci engines. 3 7 The Holden „EJ‟ „EH‟ Workshop Manual indicates a pump stroke setting of /16- /32” for EH Holden 179ci engines. I have given the values for the vent valve settings from the Stromberg Carburettor Service Manual No. BM1 issued August 1968. The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR lists EH/HD/HR Holdens as 0.55” +/-0.005”. The Master Parts Catalogue (20 Years of Holden Production) lists 0.053” main metering jets for 4,000-8,000ft and 0.051” for 8,00012,000ft high altitude operation of HR Holden 161ci engines, and 0.051” main metering jets for HR Holden 161ci economy engines. The Bendix Corporation Australia (Automotive) Pty Ltd Carburettor & Fuel Pump Service Parts Catalogue No. PC2 Issued March 1968 indicates a 0.055” main metering jet for Holden HR and HK (April 1966-1968), HT, HG and LC 161ci engines with manual transmissions, with a 0.053” main metering jet for 4,000-8,000ft and 0.051” main metering jet for 8,000-12,000ft high altitude operation, as does the Holden HR Workshop Manual for all HR Holden 161ci engines. The Bendix Corporation Australia (Automotive) Pty Ltd Carburettor & Fuel Pump Service Parts Catalogue No. PC2 Issued March 1968 indicates a 0.058” main metering jet for Holden HR and HK (April 1966 – 1968), HT and HG 186ci engines with manual transmissions, with a 0.057” main metering jet for 4,000-8,000ft and 0.055” main metering jet for 8,000-12,000ft high altitude operation, as does the Holden HR Workshop Manual for all HR Holden 186ci engines. The Master Parts Catalogue (20 Years of Holden Production) lists 0.051” main metering jets for 4,000-8,000ft and 0.049” for 8,00012,000ft high altitude operation of HR Holden 186ci (186S) engines. The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR lists a 0.058” main metering jet for all HR 186ci engines. The Bendix Corporation Australia (Automotive) Pty Ltd Carburettor & Fuel Pump Service Parts Catalogue No. PC2 Issued March 1968 indicates a 0.056” jet for Holden HR, HK, HT and HG 186S engines. The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR lists a Nº.68 drill (0.0310”) for all HR Holden engines. The Master Parts Catalogue (20 Years of Holden Production) lists a Nº.52 drill (0.0635”) idle air bleed for HD and HR Holden X2 engines, as does the Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR. 43 11 31 NOTE 38: NOTE 39: NOTE 40: NOTE 41: NOTE 42: NOTE 43: NOTE 44: NOTE 45: NOTE 46: NOTE 47: NOTE 48: NOTE 49: NOTE 50: NOTE 51: NOTE 52: NOTE 53: NOTE 54: NOTE 55: NOTE 56: NOTE 57: NOTE 58: NOTE 59: The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR lists a Nº.52 drill idle air bleed for all HR X2 engines. The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR lists a single 0.054” idle air bleed for all HR Holden 186ci engines. The Scientific Publications Workshop Manual Series No. 86 Holden covering series HK, HT, HG indicates Nº.46-57-63 drill (0.08100.0430-0.0370”) idle discharge holes for 186S engines (the HR, HK, HT and HG Holden 186S engines have identical WW Stromberg carburettors). The Master Parts Catalogue (20 Years of Holden Production) lists a Nº.65 drill (0.0350”) power bypass jet for HR Holden 161ci economy engines. The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR lists a Nº.55 drill (0.0520”) power bypass jet for all HR Holden 186ci engines. The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR lists a Nº.72 drill (0.0250”) pump discharge jet for all HR Holden 186ci engines. The Holden HD Workshop Manual lists all Holden 179ci engines as having been fitted with the BXV-2 carburettor. 3 The Holden HD Workshop Manual lists all HD Holden BXUV-2 carburettors as having a 1 /32” main venturi diameter. 7 9 The Holden HD Workshop Manual indicates a pump stroke setting of /32- /32” for all HD Holden engines. The Holden HD Workshop Manual indicates an idle vent valve lift setting of 0.050-0.060” for all HD Holden engines. The Holden HD Workshop Manual indicates a BXV-2 carburettor for all HD Holden 179ci engines. The Holden HD Workshop Manual indicates a 0.073” float needle seat orifice for all HD Holden 179ci engines. The Holden HD Workshop Manual lists a 0.058” main metering jets for all HD Holden 179ci engines, with a 0.057” main metering jet for 4,000-8,000ft and a 0.055” main metering jet for 8,000-12,000ft high altitude operation. The Holden HD Workshop Manual indicates that these jets are subject to variation by the carburettor manufacturer to meet Holden Flow Curve requirements, as does the Holden HR Workshop Manual. The Holden HR Workshop Manual lists all Holden 186ci engines as having been fitted with the BXV-2 carburettor. The Holden HR Workshop Manual lists all HR Holdens as having a 0.073” diameter float needle seat orifice. 7 9 The Holden HR Workshop Manual lists all HR Holdens as having a pump stroke vehicle setting on /32”- /32”. The Holden HR Workshop Manual lists all HR Holdens as having a vent valve setting of 0.050-0.060”. The Holden HR Workshop Manual lists all HR Holdens as having a No. 68 drill (0.0310”) idle tube. The Holden FE and FC Workshop Manual lists a No. 28-30 main discharge jet for all FE and FC Holdens. The Holden FJ Workshop Manual lists a No. 28-30 main discharge jet for all FJ Holdens. 17 19 The Holden FJ Workshop Manual indicates a pump stroke vehicle setting of /64- /64” for all FJ Holdens, as does the Holden FE and FC Workshop Manual, Holden FB Workshop Manual and Holden EK Workshop Manual for all FJ, FE and FC, FB and EK Holdens. The Holden Workshop Manual (48/215 Manual) indicates that three combinations of power bypass jets were used in production:“A” – early production, distinguished by one red paint dot on the float chamber cover (No. 63 drill, 0.037”), “B” – intermediate production, distinguished by two green paint dots on the float chamber cover (No. 66 drill, 0.033”), and 32 “C” – late production, no distinguishing marks (No. 67 drill, 0.032”). Individual parts of early, intermediate or late production jet combinations must not be mixed. The carburettor repair kit serviced by “NASCO” contains a complete jet combination and this kit must be used to service all carburettors. When carburettors are services and the setting is changed, the distinguishing marks on the top of the float chamber cover must be altered to agree with the specifications above. 5.1 EH Holden S4 Carburettor The EH Holden S4 was Holden‟s first approach to a purpose-built race vehicle, and preceeded the twin-carburettored HD and HR Holdens. The EH Holden S4 BXV-2 carburettor had a number of changes compared to the standard 179ci EH Holden motor: the vacuum power piston was changed as described in Section 6.2 below. the main metering jet was changed from 0.059" to 0.058". the idle tube was changed from #70 drill (0.0280") to #68 drill (0.0310"). The vacuum power piston change is described as the only S4-specific carburettor change in the S4 supplement to the EH Holden Workshop Manual. The main metering jet and idle tube changes are noted in the Bendix Corporation Australia (Automotive) Pty Ltd Carburettor & Fuel Pump Service Parts Catalogue No. PC2 Issued March 1968. These changes were first introduced for the S4, but later carried through for all subsequent EH Holden 179ci engines. 33 6 Assembly Diagrams The following assembly diagrams relate to early Holden Stromberg carburettors. 6.1 BXOV-1 Assembly Diagram The following diagram shows the assembly of the Stromberg BXOV-1 carburettor. I have drawn this from the Holden Workshop manuals – note that the numbering is different from that in The Bendix Corporation Australia (Automotive) Pty Ltd Carburettor and Fuel Pump Service Parts Catalogue No. PC2 issued March 1968, though the diagram is identical. Nº. 1 2 3 4 5 6 7 8 9 10 10a 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 DESCRIPTION Choke shaft and control lever assembly Choke valve attaching screw Choke wire clamp screw Manual choke lever spring Choke tube clamp screw Manual choke lever assembly (includes 3) Choke tube holder assembly (includes 5, 8 and 9) Choke tube clamp screw lockwasher Choke screw clamp screw nut Choke tube holder attaching screw and lockwasher Air horn attaching screw and lockwasher Choke valve assembly Fast idle lever Fast idle lever attaching nut Fast idle lever attaching nut lockwasher Lead ball plug Air horn assembly Air horn gasket Fast idle rod Vacuum power piston assembly Idle tube assembly Power bypass jet assembly Pump and power bypass jet gasket Pump stem cotter pin Pump rod Pump stem spring Pump piston and stem assembly Pump bypass jet assembly Pump strainer screen clip Pump strainer screen Float fulcrum pin spring Float and lever assembly Float fulcrum pin Main body and throttle body drive plug Main body attaching screw and lockwasher Float needle and seat assembly (includes 36) Float needle and seat gasket Main body assembly Pump check valve assembly Check valve plug gasket Pump check valve plug Main discharge jet Main metering jet Metering jet plug gasket Main metering jet plug Main body gasket Main body insulating spacer Throttle lever and shaft assembly Throttle valve attaching screw Pump link spring clip Pump link Pump lever Pump lever attaching nut lockwasher Pump lever attaching nut Slow idle adjusting screw Slow idle adjusting screw spring Fast idle cam Fast idle cam lever Fast idle cam lever cotter pin Idle needle valve Idle needle valve spring Throttle valve Throttle body assembly Page 34 of 148 6.2 BXUV-2/BXV-2 Assembly Diagram The following diagram shows the assembly of the Stromberg BXUV-2 and BXV-2 carburettors. I have drawn this from the Holden Workshop manuals – note that the numbering is different from that in The Bendix Corporation Australia (Automotive) Pty Ltd Carburettor and Fuel Pump Service Parts Catalogue No. PC2 issued March 1968 (and the BXOV-1 diagram above). Nº. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 64 66 68 70 72 DESCRIPTION Choke shaft and control lever assembly Choke valve attaching screw Choke wire clamp screw Manual choke lever spring Choke tube clamp screw Manual choke lever assembly (includes 3) Choke tube holder assembly (includes 5, 8 and 9) Choke tube clamp screw lockwasher Choke screw clamp screw nut Choke tube holder attaching screw and lockwasher Choke valve assembly Fast idle lever Fast idle lever attaching nut Fast idle lever attaching nut lockwasher Vent valve locknut Vent valve Lead ball plug Air horn attaching screw and lockwasher Air horn assembly Air horn gasket Reinforcing bar Vent valve spring Vent valve stem Pump stem cotter pin Pump rod Pump stem spring Pump piston and stem assembly Fast idle rod Vacuum power piston assembly Idle tube assembly Power bypass jet assembly Pump and power bypass jet gasket Pump bypass jet assembly Pump strainer screen clip Pump strainer screen Float fulcrum pin spring Float and lever assembly Float fulcrum pin Main body assembly Pump check valve assembly Check valve plug gasket Pump check valve plug Main discharge jet Main metering jet Metering jet plug gasket Main metering jet plug Pump lever attaching nut lockwasher Pump lever attaching nut Pump lever Pump link Pump link spring clip Main body and throttle body drive plug Main body attaching screw and lockwasher Restrictor wire Float needle and seat assembly (includes 56) Float needle and seat gasket Main body gasket Main body insulating spacer Throttle valve attaching screw Throttle shaft Throttle lever Throttle actuating lever Throttle lever attaching nut Slow idle adjusting screw spring Fast idle cam lever Idle needle valve Throttle valve 63 65 67 69 71 73 Throttle actuating lever lockwasher Slow idle adjusting screw Fast idle cam Fast idle cam lever cotter pin Idle needle valve spring Throttle body assembly Page 35 of 148 The BXUV-2 and BXV-2 carburettor assemblies are very similar to the BXOV-1 diagram given above, with the following changes: Volume Restrictor Rod (Restrictor Wire) From EH through HR Holdens, the Stromberg BXUV-2 and BXV-2 carburettors were fitted with volume restrictor rods (sometimes referred to as restrictor wires). The WW carburettor used on HR 186S engines also had a similar rod. The rods are inserted into the vertical idling passage in the lower face of the main body assembly (after separating the main and throttle bodies). The purpose of the rod is to reduce the cross-sectional area of the idle channel to provide a good idle under extremely hot operating conditions. Idle vent valve (Anti-percolator Valve) From EH through HR Holdens, the Stromberg BXUV-2 and BXV-2 carburettors were fitted with idle vent valves (sometimes referred to as anti-percolator valves). The WW carburettor used on HR 186S engines also had a similar valve, though of different operation. The BXUV-2 and BXV-2 valves consist of a seat fitted into the top of the air horn directly above the accelerator pump stem. The valve seat is fitted with a valve stem and spring from underneath, then a valve “washer” is screwed on from above. The gap between the “washer” face and seat is adjusted at idle to the settings tabulated below, taking care that the choke is off. The “washer” is then locked into position with a locknut. The aim of the idle vent valve is to vent buildup of vapours that form in the float chamber during idle under hot conditions, as this type of percolation (fuel boiling) in the fuel discharge system can cause poor idle and hard hot-starting. At idle, the accelerator pump stem rises upwards, and opens the valve. When moving away from idle, the accelerator pump stem drops downwards, allowing the idle vent valve to close. Note that whilst early Holdens vent the fuel bowl to atmosphere, later model cars tend to vent the fuel bowl through a carbon canister to minimize emissions. Reinforcement bar From EH through HR Holdens, the Stromberg BXUV-2 and BXV-2 carburettors were fitted with air horn reinforcement bars. The bars are a simple piece of bent steel, fitted to the top front edge of the air horn by the two outer attaching screws. The reinforcing bar provides a more positive seating of the air horn to the main body. Australian Stromberg Code numbers were often stamped on the reinforcing bars. Page 36 of 148 Vacuum Power Piston Assembly From mid-1964 onwards (during production of EH Holdens), the BX-Model main body was modified to allow the vacuum power piston assembly to be placed in a lower position. This lead to the use of different 5 (longer) vacuum power pistons – 48-mid EH Holdens use a 2 /32” overall length piston, whilst mid-EH 9 Holden onwards use a 2 /16” piston. The pistons are not interchangeable. The diagram below indicates the changes to the main bodies and piston assemblies. Flange Bolt Spacing 3 The bolt spacing for the BXOV-1 carburettor (2 /8”) is different from that of the BXUV-2 11 and BXV-2 carburettors (2 /16”). Pump Lever The pump lever for the BXOV-1 carburettor is different from that of the BXUV-1 and BXV-2 carburettors. The slot through which the throttle shaft mounts is the same width, though the 7 length (the dimension highlighted in the diagram to the right) is /32” for the BXOV-1 and 17 ~ /64” for the BXUV-2 and BXV-2 carburettors (this is because the BXOV-1 throttle shaft thread diameter 3 is 0.215” and 0.150” across the flat for a /8”AF nut, whilst the larger BXUV-2 and BXV-2 is 0.258” across 7 the threads and 0.170” across the flats for a /16” AF nut). Whilst the BXUV-2 and BXV-2 pump lever will fit on the BXOV-1 carburettor throttle shaft, the increased clearance leads to a sloppy accelerator pump response. Throttle Shaft The throttle shafts for BXOV-1 carburettors have the throttle lever fitted and the end of the throttle shaft peined over. The BXUV-2 and BXV-2 carburettors do not have the throttle shaft peined – rather a separate nut and lockwasher is fitted. Whilst minor, this has an impact when using BXOV-1 carburettors in twin carburettor format with W-clip linkages – see Section 10.4 below. Note that there are other significant differences between the BXOV-1, BXUV-2 and BXV-2 carburettors (venturi size, throttle bore diameter, jetting etc) which are not as readily apparent in the carburettor assembly, and which will be further explored below. Page 37 of 148 7 Disassembly and Overhaul Process The following process describes the process of removal, disassembly and overhaul (often referred to as “putting a kit through”) for a Stromberg BXOV-1 carburettor. I have used the numbering from the Holden Workshop manual diagrams given above. 7.1 Kit Contents and Pre-disassembly The following numbers indicate the Fuelmiser carburettor overhaul kits available for Holden Stromberg carburettors: Vehicle Holden FX-HJ, LC-LH Torana Holden HX-HZ, LX-UC Torana, Holden HR-HZ, LC, LH and LX Toranas, VB Commodore Carburettor Model BXOV-1, BXUV-2, BXV-2, BXUV-3 BX WW Fuelmiser Kit Nº. SSB-652 SSB-655 SSB-651 The BXOV-1 carburettor overhaul is primarily completed with a Fuelmiser kit, part number SSB-652. The kit contains the following parts: a) and b) two main body gaskets (45), c) and d) two main body gaskets not used in the overhaul of BXOV-1 carburettors (I suspect these are for BXV carburettors), e) and f) two flange gaskets (not numbered above – see Note 1 below), g) an air horn gasket (17), h) a pump lever (51 – see Note 2 below), i) a pump link (50), j) a fast idle cam cotter pin (58), and a fast idle rod cotterpin (not numbered in the drawing above), k) a pump stem cotter pin (23), l) a pump piston and stem assembly (26), m) a pump link spring clip (49), n) a float fulcrum pin spring (30), o) a 0.076” diameter float needle valve seat assembly (35), p) a float needle valve (35), q) two plastic caps for blocking off vacuum lines (not used in the overhaul of BXOV-1 carburettors), r) a metering jet plug gasket (43), s) a check valve plug gasket (39), t) a float needle valve and seat gasket (36), u) a power bypass jet gasket (22) and a pump bypass jet gasket (22). Page 38 of 148 The kit also contains a very basic assembly drawing and a leaflet describing how to condition the accelerator pump plunger. Note 1: The two gaskets supplied in the Fuelmiser SSB-652 kit (a) and b) in the photograph below are not suitable for the overhaul of a BXOV-1 carburettor: o 11 15 Gasket a) suits a N . 3 (S.A.E. size 1½”) flange with throttle barrel diameter of 1 /16" and 2 /16” bolt spacing such as on the BXUV-3 carburettor fitted to VC Valiants, whilst o 7 11 Gasket b) suits a N . 2 (S.A.E. size 1¼”) flange with throttle barrel diameter of 1 /16” and 2 /16” bolt spacing such as on the BXUV-2 and BXV-2 carburettors. The correct gasket to suit the BXOV-1 carburettor (c) in the photograph) is available from the Carburettor Service Company. The image in the middle below shows the correct gaskets sitting on the bottom of a BXOV-1 throttle body. The image to the right shows gasket b) (the smaller of the two supplied in the kit). Note the large gap between the gasket bore and the throttle body bore, and the misalignment of the flange bolt holes, highlighting the need to buy the additional (correct) gasket. . Note 2: The Fuelmiser SSB-652 kit does not supply the correct pump lever (51) for BXOV-1 carburettors. The pump lever for the BXOV-1 carburettor is different from that of the BXUV-1 and BXV-2 carburettors. The slot through which the throttle shaft mounts is the same width, though the length (the 7 dimension highlighted in the diagram to the right) is /32” for the BXOV-1 and 17 ~ /64” for the BXUV-2 and BXV-2 carburettors. Whilst the BXUV-1 and BXV-2 pump lever will fit on the BXOV-1 carburettor throttle shaft, the increased clearance leads to a sloppy accelerator pump response. The picture above shows the pump lever supplied in the Fuelmiser SSB-652 kit (upper image, suitable for BXUV-2 and BXV-2 carburettors), together with the correct one (lower image) for BXOV-1 carburettors. The correct BXOV-1 pump lever is again available from the Carburettor Service Company. Note 3: Fuelmiser supply a separate accelerator pump system lost motion prevention spring (part No. SBP-043 – see image to the right) which is not part of the SSB-652 overhaul kit. The SBP-043 spring is an additional spring not originally installed on factory Stromberg carburettors. Over time (the last half century…), the throttle shaft bearing areas, the linkage to the pump rod and the pump rod guide (part of main body) can wear. This can result in a delayed accelerator pump plunger movement when you accelerate, giving some lag (or sluggish feeling). The Fuelmiser accelerator pump system lost motion prevention spring adds some tension to the accelerator pump system, taking out some of the slack from the worn parts. This can give crisper acceleration. It is recommended that the Fuelmiser accelerator pump system lost motion prevention spring be fitted during overhaul. Page 39 of 148 Note 4: The Fuelmiser kit does not contain a new split pin for the throttle control upper rod. Prior to disassembling the carburettor, it is worthwhile checking for worn throttle shaft bearing areas. To do so, start the engine and leave it idling with the air cleaner in place. Spray some WD40 around the main body where the throttle lever and shaft assembly (47) passes through either side of the throttle body assembly (62), using the red squirty straw on the can of WD40 to get at the right area. Make sure there is no grease or dirt around the area that could block the WD40 from getting to the throttle body. If the engine revs pick up, then the throttle shaft bearing areas are worn (letting in WD40 under vacuum to fuel the motor) and should be professionally rebushed during the rebuild. 7.2 Special Tools The following tools can make the overhaul process significantly easier: GMH tool 6A10 (Stromberg part N . 73605) is used for two purposes. One end of the tool is used to remove and replace the vacuum power piston assembly. The other end of the tool is used to bend the float arm to adjust the fuel level in the carburettor. The tool may be replaced by a pair of circlip pliers (to remove the vacuum power piston assembly) and a screwdriver and pair of pliers (to bend the float arm). GMH tool 6A11 (Stromberg part N . 73608) is used to remove the main discharge jet from the carburettor main body. The tool has a fine conical thread which enables it to be screwed into the hole in the base of the main discharge jet. The o threads of the tool grip the jet, allowing it to be pulled out. A N 1. screw extractor 1 o (suitable for /8-¼ “ or M5-M6 bolts) or N . 2 screw extractor 5 (suitable for ¼- /16” or M6-M8 bolts) will also work for this task. If the main discharge jet is very stuck, it may be necessary to use a pulling fixture to remove it. This is further explained below. GMH tool 6A12 (Stromberg part N . 73606) is a socket type wrench used to remove and install the main metering jet. This is probably the only “special tool” which is indispensable for overhauling Stromberg carburettors. The tool is available aftermarket from Rocket Industries and the Carburettor Service Company. GMH tool 6A20 is an accelerator pump installer. It is used when installing the accelerator pump piston in its bore in the carburettor main body. The tool smoothes the bore transition so that the piston leather does not crease or wrinkle. In operation the tool is installed into the piston bore, then the pump piston is inserted into the bore of the tool. The pump piston must be fully installed before the tool is removed. This tool is not necessary for overhauling Stromberg carburettors – care during the piston installing process eliminates the need for the tool. Note that there is also a float level gauge (Stromberg part number 73725) which is used to set the float levels on Stromberg WW-Model carburettors. o o o Page 40 of 148 One non-genuine tricky tool is a large flathead screwdriver with a home-made slot cut in the centre of the blade. This allows you to pull out the power bypass jet and accelerator bypass jet without crunching the centre pin assemblies. You can however get away with a normal screwdriver though (and most people do). 7.3 Removing the Carburettor from the Vehicle 1. Remove the air cleaner wingnut, air cleaner lid and filter element. Slacken off the slot-head bolt under the filter base then remove the base. 2. Remove the split pin from the throttle control upper rod and disengage the rod from the carburettor. Leave the rod hanging from the rest of the throttle linkage assembly. Disconnect the fuel line flare nut (½” AF) and vacuum line 3 flare nut ( /8” AF) from the carburettor. 3. 4. Slacken off the choke tube clamp screw (5) and choke wire clamp screw (3). Pull the choke cable out from choke tube holder assembly (7). Leave the choke cable hanging from the firewall. Remove the carburettor flange nuts (½” AF) and withdraw the carburettor from the manifold. Note that there is a Bakelite spacer under the carburettor. When removing the spacer, take care to pull it up squarely and gently, as flexing the spacer can cause them to crack. Cracked spacers will cause a vacuum leak and poor running. Give the outside of the carburettor assembly a clean with some kerosene on a rag to get rid of the worst of the oil and dirt prior to disassembly. 5. 6. 7.4 Disassembling the Air Horn 1. With the carburettor on a bench, remove the cotter pin (not numbered in the drawing above) from the lower end of the fast idle rod (18) then remove the rod. Note that the carburettor in these photographs is missing the fast idle cam. Undo the five flat-head air horn attaching screws and lockwashers (10A) and the choke tube holder attaching screw and lockwasher (10). Note that 10A and 10 are very similar – 10 is slightly longer to allow for the thickness of the choke tube holder. Lift off the air horn assembly (16) 2. Page 41 of 148 and air horn reinforcing bar (if fitted – the BXOV-1 carburetor in these photographs had been fitted with an EH 149ci air horn reinforcing bar). 3. Unscrew the vacuum power piston assembly (19) from the air horn assembly (16) using a pair of circlip pliers (or the original GMH Tool 6A10) to engage the two drive slots. 4. Remove the /16” AF fast idle lever attaching nut (13), lockwasher (14) and lever (12). For BXUV-2 and BXV-2 carburettors, remove the idle vent valve locknut, then unscrew the idle vent valve washer. Remove the idle vent valve stem and spring assembly. 5 5. The choke assembly (1, 2, 4 and 11) is a pain to remove as the choke valve attaching screws are staked. For most overhauls, it is not necessary to remove the choke assembly. Equally, the lead ball plug (15) is not removed for most overhauls. 7.5 Disassembling the Main Body 1. Remove the pump link spring clip (49) from the pump link (50) and remove the link. 2. Remove the pump piston and stem assembly (26) from the main body assembly (37). Note that the air horn gasket (17) will also come along as it is held in place by the pump piston. 3. Holding the pump piston and stem assembly (26) in your hands, squeeze down the pump rod (24) to compress the pump stem spring (25). Remove the p ump stem cotterpin (23) then release the spring pressure. Remove the pump rod (24), pump stem spring (25) and air horn gasket (17) from the pump piston and stem assembly (26). 4. Using a large flat bladed screwdriver, unscrew and remove the pump bypass jet assembly (27) and the associated gasket (22) from the main body (37). 5. Using a large flat bladed screwdriver, unscrew and remove the power bypass jet assembly (21) and the associated gasket (22) from the main body (37). Page 42 of 148 6. Using a flat bladed screwdriver , unscrew the idle tube assembly (20) from the main body (37). 7. Using a /16” AF spanner, remove the float needle valve and seat assembly (35) and its associated gasket (36) from the main body (37). Insert a small screwdriver between the float fulcrum pin (32) and the main body (37) and pry off the float fulcrum pin spring (30) with a twisting motion. Hold your hand over the float chamber as you are doing so to prevent the spring from flying off. Remove the float fulcrum pin (32) and float and lever assembly (31) from the main body (37). 9 8. 9. 10. Using a large flat bladed screwdriver, remove the main metering jet plug (44). Unscrew the main metering jet (42) using a jet key (or GMH tool 6A12), and remove both the jet and associated gasket (43) with needle nosed pliers. Remove the main discharge jet using GMH tool 6A11 or a screw extractor (see notes above). Note that the threads/marks formed in removing the main discharge jet will not affect the metering characteristics of the jet, and it need not be discarded unless otherwise damaged. If the main discharge jet is firmly stuck in place, it may be necessary to use a pulling fixture to remove them – this is a process I have borrowed from Flathead Youngin from the HAMB. To do this: a) soak the stuck main discharge jet in WD40 or similar penetrant for several days. b) a small tap is driven into the main discharge jet, aiming to drive as square as possible. The tap is driven to form only around three good threads. I have not tried this on B-Model Strombergs, but o o Stromberg 97‟s usually use a N . 5 or N . 6 tap. c) back the tap out and screw in a bolt of the same size as the tap. Do this gently, as the main discharge jet material is soft brass. d) fit a washer onto the bolt, and wind on a nut (or wingnut) until it bottoms on the main metering jet plug boss. e) gently wind the nut down so that the bolt pulls out the main discharge jet. The photos below show the process being undertaken on a Stromberg 97. Page 43 of 148 11. Using a large flat bladed screwdriver, remove the pump check valve plug (40), the pump check valve assembly (38) and associated copper gasket (39). The pump strainer screen (29) and associated clip (28) are a pain to remove (and almost impossible to find parts for once you punch a hole in the screen or sproing the clip across the workshop at the speed of light). For most overhauls, it is not necessary to remove them. 7.6 Disassembling the Throttle Body 1. Remove the main body attaching screws and lockwashers (34). Separate the throttle body (62) from the main body insulating spacer (46) and main body (37). Remove the associated main body gaskets (45). 2. Unscrew and remove the idle needle valve (59) and associated spring (60). 3. 4. Unbolt and remove the /8” AF pump lever attaching nut (53) and lockwasher (52). Remove the pump lever (51). Remove the fast idle cam lever cotter pin (58), the fast idle cam (56) and lever (57). Unscrew and remove the slow idle adjusting screw (54) and spring (55). 1 7 Remove the /8” NPT vacuum line adapter ( /16” AF). 3 5. 6. The throttle lever and shaft assembly (47, 48, 61) is a pain to remove as the throttle valve attaching screws are staked. For most overhauls, it is not necessary to remove the throttle assembly. Equally, the main body and throttle body drive plugs (33) are not removed for most overhauls. The photographs below illustrate some of the assemblies and vacuum passages inside the carburettor assemblies: Page 44 of 148 7.7 Cleaning and Inspection 1. Clean all parts in some petrol to remove most of the oil and dirt. Ensure good ventilation and no open flames when washing parts with petrol (or any of the solvents below). An alternative is to use one of the spray type “carburettor and throttle body cleaners” available from SuperCheap, Repco etc. Most of the cleaners available are made for spraying down a carburettor throat with the engine running, rather than detailed cleaning of a disassembled carburettor. They tend to be mainly solvent, evaporate very quickly, and are this not much use for “soaking” parts. They are also not very suitable for removing the carbon (“coke”) that builds up inside carburettors (what little they dissolve tends to restick as the cleaner evaporates). From trying some of them, I personally believe these spray cleaners are little (if any) better than using straight petrol for cleaning disassembled carburettors. Many forums recommend the use of “dip” cleaners to soak parts in (for example Berrymans B9 Chem Dip, which has a number of solvents, cresols and sodium bichromate). Some hunting has shown that “dip” cleaners are very hard to come by in Australia. One that is available is Yamalube Carburettor Cleaner, though I have not tried it. Paint thinners also does a fair job of removing the gunk. 2. Blow out all passages with compressed air in the opposite direction to normal flow. Pay particular attention to the pump strainer screen (29) as it may trap dirt in normal service. Do not rod-out any jets or passages with drills or wires unless absolutely necessary as it is likely to change their flow characteristics. 3. Use a steel rule to check that the main body assembly (37) and air horn assembly (16) are flat where they join. Similarly check the main body assembly (37) and main body insulating spacer (46) mating surfaces and the main body insulating spacer (46) and throttle body assembly (62) mating surfaces. Should any of these surfaces not be flat, professional milling (or replacement) may be required. 4. Check the upper and lower idle discharge holes in the throttle body assembly (62) to make sure they have no carbon deposits. 5. Examine the idle needle valve (59). If it is ringed or grooved it must be replaced. 6. Inspect the main discharge jet (41) for burrs at the venturi end. Burrs may be carefully removed with a file, taking care not to change the shape or angle of the jet. 7. Inspect the main metering jet (42), pump bypass jet assembly (27), power bypass jet assembly (21), idle tube assembly (20) to ensure they are clean. 8. Check the float and lever assembly (31) for dents and punctures. 9. Check the vacuum power piston assembly (19) for deep scratches or scores on the piston surface. Check that the piston is a free fit in its cylinder. 10. Check the operation of the valve in the power bypass jet assembly (21) by putting the threaded end into your mouth and sucking. The valve should not pass any air until the valve stem is pushed in. Leaking power bypass jet assemblies will cause the engine to run rich at cruise conditions. This can be cured by running slightly leaner main metering jets, though replacing the leaking power bypass jet assembly is a wiser choice. 11. Check the throttle lever and shaft assembly (47) where it passes through either side of the throttle body assembly (62) for looseness. Worn assemblies should be professionally rebushed during the rebuild. Check that the throttle valve (61) opens and closes correctly. 12. Check the choke shaft and control lever assembly (1) where it passes through either side of the air horn assembly (16) for looseness. Check that the choke valve assembly (11) opens and closes correctly. Check that the choke poppet valve (part of the choke valve assembly (11)) is clean and free to move and seat. Page 45 of 148 7.8 Assembly and Reinstallation 1. Install the idle needle valve (59) and idle needle valve spring (60) into the throttle body assembly 7 (62). Screw them in gently until they are all the way in (do not overtighten!), then back them out /8 of a turn (1 turn for BXUV-2 and BXV-2 carburettors). 2. Install the fast idle cam (56) and fast idle cam lever (57) to the throttle body assembly (62), securing them in place with the new fast idle cam cotter pin (58) supplied in the Fuelmiser kit. 3. Install the pump lever (51), pump lever attaching nut (53) and associated lockwasher (52). Take care to use the separately supplied pump lever rather than the one from the Fuelmiser kit (see notes above). 4. Reinstall the slow idle adjusting screw (54) and slow idle adjusting screw spring (55) into the throttle lever and shaft assembly (47). Back off the slow idle adjusting screw (54) until the throttle valve assembly (61) seats in the throttle body assembly (62). 5. Install the main discharge jet using GMH tool 6A11 or a screw extractor (see noted above). Ensure the jet is correctly located in the main body – the mitered face of the jet must be parallel with the direction of air flow. 6. Install the main metering jet (42) into the main body assembly (37), using a jet key (or GMH tool 6A12). Install a metering jet plug gasket (43) from the Fuelmiser kit, and fit the main metering jet plug (44) with a flat bladed screwdriver. 7. Install the pump check valve assembly (38) into the main body assembly (37) using a flat bladed screwdriver. Install a check valve plug gasket (39) from the Fuelmiser kit, and fit the pump check valve plug (40). 8. Install the main body assembly (37) and main body insulating spacer (46) on the throttle body assembly (62) using main body gaskets (45) from the Fuelmiser kit. Take care to select the right gaskets from the Fuelmiser kit (lay them over the old ones to check) as the kit has two spare gaskets which do not suit BXOV-1 carburettors. 9. Install the idle tube assembly (20) into the main body assembly (37) with a flat bladed screwdriver. 10. Install the power bypass jet assembly (21) into the main body assembly (37) using a power bypass jet gasket (22) from the Fuelmiser kit. Note that the original Stromberg gaskets were fibre, and that the Fuelmiser kit gaskets are alloy. Be careful as the power bypass jet assembly (21) and the pump bypass jet assembly (27) are very similar. The power bypass jet assembly (21) has a small stem which protrudes above the body of the jet – see image on the left above. The pump bypass jet assembly (27) stem does not protrude above the body of the jet – see image on the right above. 11. Install the pump bypass jet assembly (27) into the main body assembly (37) using a pump bypass jet gasket (22) from the Fuelmiser kit. Note again that the original Stromberg gaskets were fibre, and that the Fuelmiser kit gaskets are alloy. 12. Install the float fulcrum pin (32) in the float and lever assembly (31) hinge. Place the resultant assembly into the float chamber so that the ends of the float fulcrum pin (32) fit into the grooves in each side of the float chamber. Place the float fulcrum pin spring (30) from the Fuelmiser kit into the grooves on each side of the float chamber and force the bowed part of the spring down to clip under the projection on the side of the float chamber. 13. Assembly the float needle valve and seat assembly (35) from the Fuelmiser kit, and install it into the main body assembly (37), using a float needle valve and seat gasket (36) from the Fuelmiser kit. Note that the gasket in the Fuelmiser kit is alloy. Page 46 of 148 14. The float level can now be bench-set. For steel-tipped float needle valves, the float is held up by hand until the needle valve is firmly closed on its seat. For viton-tipped float needle valves, the main body assembly is turned upside down and the weight of the float used to hold the needle valve firmly closed on its seat. In both cases, the distance from the top centre of the float to the top surface of the main body (without the gasket) is measured. Bend the float lever (either 1 with GMH Tool No. 6A10, or a screwdriver/pair of needle nose pliers) until this distance is /8”. When adjusting the float tab, don't force the float needle into its seat as it may damage the seal. Note that bench-setting the float level gives a good starting point, but must be checked again once the carburettor is reassembled, installed and the engine running (see Section 8.1 below). 15. For BXOV-1 carburettors, snap the tip off the pump piston and stem assembly (26) supplied in the Fuelmiser kit (as the BXOV-1 carburettor does not have an idle vent valve – the tip is left in place for BXUV-2 and BXV-2 carburettors). To prevent possible engine flat spots or hesitation upon acceleration, condition the pump plunger leather cup by inserting a screwdriver blade under the cup (between the leather cup and the brass support), flaring the skirt outwards as the blade is revolved around the main body. Two or three revolutions will render the leather soft and pliable. Reshape the cup with your fingers. Soak the cup in fuel, then revolve the pump piston and stem assembly (26) as it is inserted down into the pump well. Recheck for proper fit – light to medium drag should be felt as the assembly is worked up and down pump well. 16. Fit the pump stem spring (25) on the pump piston and stem assembly (26). 17. Position the cone shaped lost motion prevention spring (Fuelmiser SBP043) over the pump stem spring (25) and pump piston and stem assembly (26), with the larger coils facing downwards seating on the casting above the pump well. 18. Position the air horn gasket (17) from the Fuelmiser kit on the main body assembly (37). 19. Insert the pump rod (24) into main body assembly (37), compressing both the installed springs until the pump piston and stem assembly (26) stem protrudes through the hole in the pump rod (24) allowing fitment of the pump stem cotter pin (23). A new pump stem cotter pin (23) is included in the Fuelmiser kit. 20. Install the pump link (50) between the bottom of the pump rod (24) and the centre hole of the pump lever (51). Spring the pump link spring clip (49) onto the pump link (50). A new pump link (50) and pump link spring clip (49) are included in the Fuelmiser kit. 21. The accelerator pump stroke can now be bench set, which saves having to do it once the carburettor is installed. Measure and record the distance from the top of the accelerator pump piston stem assembly (26) to the top face of the main body assembly (37, with the gasket removed). Open the throttle fully and again check and record the distance. The difference between the two 17 19 measurements (which is the accelerator pump stroke) should be /64- /64” (note that BXUV-2 and BXV-2 carburettors having varying settings for accelerator pump stroke bench setting – see table in Section 5 above). If the difference is more or less than this range, the accelerator pump stroke can be changed by bending the top horizontal portion of the accelerator pump rod (24). Two bends are need for each adjustment to keep the hole in the pump rod parallel with the pump stem. 22. Install the fast idle lever (12), fast idle lever attaching nut (13) and associated lockwasher (14) to the choke shaft and control lever assembly (1). 23. Install the vacuum power piston assembly (10) into the air horn assembly (16) and tighten it with circlip pliers (or GMH tool 6A10). Check the piston for free movement in the cylinder. Do not lubricate the piston. 24. For BXUV-2 and BXV-2 carburettors, install the idle vent valve stem and spring assembly from underneath the air horn. Fit the idle vent valve washer and locknut, leaving them loose for now. Note Page 47 of 148 25. 26. 27. 28. 29. 30. 31. 32. 33. that the idle vent valve is set only once the carburettor is reassembled, installed, the engine running, the idle has been set and the accelerator pump stroke checked (see Section 8.4 below). Install the air horn assembly (16) onto the main body assembly (37). Install the five air horn attaching screw and lockwashers (10A), being careful to put the longer choke holder attaching screw and lockwasher (10) onto the correct corner together with the choke tube holder assembly (7). Tighten the screws securely and evenly. Connect the fast idle rod (18) between the fast idle lever (12) and fast idle cam lever (57). Secure the rod in place with a cotterpin (not numbered in the drawing above) from the Fuelmiser kit. 1 7 Install the /8” NPT vacuum line spacer ( /16” AF). Place some rag in the inlet manifold to stop rubbish dropping in, then clean the manifold face. Clean the Bakelite spacer. Install new gaskets, the spacer and carburettor onto the inlet manifold flange nuts. Note that the gaskets in Fuelmiser kit are incorrect for BXOV-1 carburettors, and must be replaced with alternative ones. When seating the spacer, take care to pull it up squarely and gently, as flexing the spacer can cause them to crack. Cracked spacers will cause a vacuum leak and poor running. Refit the choke cable to the choke tube holder assembly (7). With the choke knob pushed in at the dash, tighten the choke tube clamp screw (5) and choke wire clamp screw (3). Check the operation of the choke from inside the vehicle, confirming that the choke plate fully opens and closes. Reconnect the fuel and vacuum control lines. Install the throttle control upper rod to the carburettor and fit a new split pin. The air cleaner may remain off the vehicle until it is tuned as per the guidance below. 7.9 Replacement Parts In addition to the Fuelmiser parts noted above, some parts are available from Stromberg Carburetor (see image below, Stromberg Carburetor parts are above the Australian B-Model parts). The parts have been verified by fitting against an Australian BXOV-1 carburettor: Page 48 of 148 Part Air horn attaching screw and lockwasher (item 1 in the image above) Bendix Australia Part Number 909521-K36 and 909522-K36 Stromberg Carburetor Part Number Comments The threads are slightly sharper in the Stromberg Carburetor part, but a decent fit to the B-Model carburettor. The Stromberg Carburetor part is stainless. The Stromberg Carburetor plug head is ½” diameter, whilst the B7 Model is /16”. The Stromberg Carburetor part engages by only one thread on the B-Model carburetor and seats on the outside of the body (rather than the milled internal seat) unless the plug head is ground back to ½” diameter. Australian B-Model sizes were 0.049”-0.059”, with some need for even smaller sizes for the guys running twin and triple carburettors. Stromberg Carburetor have 0.033”0.050” and can make bigger on demand. The Genuine Stromberg screw is a different thread (10-32x¾”) and hence not useable in B-Model carburettors. The spring is close, but a little longer (and stainless steel) and works nicely with the BModel carburettors. Genuine Stromberg spring is slightly longer, but both screw and spring are a good fit for the BModel carburettors. Genuine Stromberg gaskets are paper, whilst Fuelmiser gaskets are malleable copper. 31095K Main metering jet plug (item 9 in the image above) P24678 Similar to the centre plug piece in the 9522K kit. A brass float 382537 9550K Main metering jet (item 5 in the image above) P19442-size 9533K-size. Slow idle adjusting screw and spring (spring is item 3 in the image above) Idle needle valve and spring (items 7 and 4 in the image above) Main metering jet plug gasket (item 10 in the image above) Pump check valve assembly (item 6 in the image above) Throttle/choke valve attaching screws (not pictured above) Power bypass jet assembly (item 2 in the image above) P15456, 2376174 or 903925-K1 for the screw, P15831 for the spring. P15478 for the screw, P15481 for the spring. 9589K Should be similar to your 9541K. Pretty much the same. Spring a tad longer. 383079 9563K P18144 9573K Identical swap. P22573 or P20904 9586K Identical swap. Note that the head of the B-model power valve is 0.407” diameter, whilst the head of the Stromberg Carburetor jet is 0.395” diameter. Despite the slightly smaller head, the Stromberg 97 power bypass jet seats well in the B-Model body. 382880-size 9594K-size Page 49 of 148 Australian B-Model sizes ranged from #54-#67 drill, with some need for even smaller sizes (higher drill number) for the guys running twin and triple carburettors. Stromberg Carburetor have #60-#71 and can make bigger on demand. For the curious, the following GMH B-model parts were also checked against the Stromberg Carburetor EE-model parts – whilst they look very similar, they are sadly not a direct fit. They may in some cases however be made to fit (more or less) with some machining: A choke shaft and plate (Bendix Australia part number 2376088 and P24046 respectively). These are similar to the Stromberg Carburetor parts 9546K and 49K. However, the shaft is a different style, the plate is a different shape (EE-Model is round) and the B-model screws are not countersunk like the EE-model. A stainless steel float pin. These are different to the EE-1 pin (no threaded end on the Australian one). A choke cable mounting bracket (Bendix Australia part number 385175 or 385174) – very different to the Stromberg Carburetor part number 9552K-B. A throttle plate (Bendix Australia part number 385050 or 2376062). Looks similar to the Stromberg Carburetor part number 9585K. However the Australian one is thinner, slightly bigger and steel – the EE-Model is brass. A throttle shaft. The Stromberg Carburetor shaft is longer and thicker (7mm) than the B-Model shaft (¼” or 6.35mm). A main discharge jet (Bendix Australia part number 385178). Very different to the Stromberg Carburetor part 9534K. An idle jet (Bendix Australia part number P21778-size, and item 8 in the image above). Whilst similar 17 to the Genuine Stromberg part 9542K, the B-Model part is /64” shorter. The longer EE-Model part clashes with the B-Model main discharge jet, though is otherwise a fit. Genuine Stromberg offers the #70 drill jet, with Australian B-Model jet sizes being #68 and #70 drill. A float (Bendix Australia part number 382537). This is very similar to the Genuine Stromberg part 9550K, though the B-Model float has a slightly different hinge and has one corner removed. This part would require little modification to fit the BModel carburettor. Page 50 of 148 Note that the needle and seat assembly (Bendix Australia part numbers 385053 and 2376000) which is made by Fuelmiser is also made by Genuine Stromberg. The Genuine Stromberg part (9564K) is a two-ball type rather than the traditional needle and seat. The 7 Genuine Stromberg threads ( /16x24 on the carburettor end and ½x20 on the fuel line end) appear to match the B-Model, though I have not trial fitted one. Page 51 of 148 8 Tuning and Troubleshooting Stromberg carburettors are renowned for being fiddled with. The image of an early Holden with the bonnet up and someone bent over the engine “tuning” the carburettor is almost iconic-Australian. Like any carburettor, it is often easy to blame the carburettor for a host of other ignition faults. The tuning below assumes that ignition, timing, valve train and engine condition (e.g. compression) are in fair shape. The basic Stromberg tune-up steps (say after overhauling the original carburettor on the car) are: Setting the fuel level, Setting the idle speed and idle mixture, and Checking the accelerator pump stroke. Note that setting the idle mixture applies only to engine performance at idle conditions – not at normal cruising, accelerating or under heavy load. Where the vehicle is running incorrectly, or where new carburettors are fitted, there are an additional three tuning parameters: Tuning the accelerator pump stroke and duration (which determines throttle response), Changing the main metering jets (which sets the mixture under cruising conditions), and Changing the power bypass jets (which sets the mixture under heavy load). main metering and idle systems suction power system suction accelerator system suction lower fuel level Fuel level is harder to set “by eye”, and some basic tools are needed: A small steel rule to measure the fuel level. A tool to bend the float lever. There is a GMH tool to do this (Tool No. 6A10), though a screwdriver/pair of needle nose pliers works just as well. To set the fuel level: 1. 2. Place the vehicle on level ground. Warm the car up to normal operating condition. Turn the engine off and remove the air cleaner. Page 52 of 148 overflow from main discharge jet upper fuel level 8.1 Fuel Level Fuel level is adjusted so that the vehicle does not run out of fuel (lean out) under cornering or acceleration (too low) or burp uncontrolled into the engine (too high). The chart to the right shows how each of the fuel systems loses suction as the fuel level drops in a Stromberg BXOV-1 carburettor fuel bowl. 2.5 Fuel height (") 2 1.5 1 0.5 empty full 0 3. 4. Remove the five air horn attaching screws and lockwashers (10A) and the choke tube holder attaching screw and lockwasher (10). Place the screws somewhere away from the engine… dropping them down a carburettor throat can lead to catastrophic engine damage. Remove the air horn assembly (16). Raise the air horn gasket (17) to an out of the way position. Block off the power system vacuum passage in the carburettor main body (37) with a piece of PVC tape (see diagram to the right where the vacuum passage has been coloured red). If this passage is not blocked off during fuel level setting, the manifold will draw in air (bypasses the carburettor) and will not run well. 5. 6. 7. Start the engine and measure the level of fuel in the float bowl with a steel rule. Measurements are taken from the liquid surface to the top 5 11 of the main body (37). The measurement should be /8”- /16”. If the measurement is outside this range, stop the engine and bend the float lever (either with GMH Tool No. 6A10, or a screwdriver/pair of needle nose pliers). When adjusting the float tab, don't force the float needle into its seat as it may damage the seal. Remove the PVC tape from the vacuum passage, smooth down the air horn gasket (17) and refit the air horn assembly (16). Reintall the five air horn attaching screws and lockwashers (10A) and the longer choke tube holder attaching screw and lockwasher (10), taking care not to drop them down the carburettor throat. Tighten the screws firmly and evenly. Reinstall the air filter. Stromberg carburettors operate on approximately 2½-4½ psi of fuel inlet pressure (SUs are happy to run on 1½-3½ psi and overflow around 5 psi, and 350 Holley carburettors run happily at 5-7psi). Too low a fuel pressure and the fuel level drops in the bowl. Too high a level and the needle and seat is forced open, flooding the engine. This is a particular risk when the original Holden mechanical fuel pump has been replaced with an electric inline pump – see chart and table below. When using inline fuel pumps (notably Holley), a pressure regulator is mandatory to prevent flooding. Fuel Pump Early Holden (grey/red glass bowl) Later Holden (blue motor steel can) Carter GP4603HD Carter GP4070 Carter GP4594, GP4389, GP4259 and GP4602RV Carter GP4600HP Holley Red Carter GP4601HP Holley Blue Holley Black Maximum Pressure (psi) 4½ 3.9 6 6 8 5 10 18 18 18 Free Flow (GPH) 9 9½ 43 72 72 100 100 100 110 145 Page 53 of 148 160 140 Early Holden (grey and red) fuel pump: 3½ -4½ psi, 9 GPH freeflow 120 100 Flow (GPH) 80 Holley red Holley blue Holley black 60 Stromberg inlet pressure 350 Holley inlet pressure SU inlet pressure early Holden fuel demand 0 2 4 6 8 10 12 14 16 18 Prressure (psi) 40 20 Pressure regulator required to drop Holley red pressure down to Stromberg 3½ -4½ psi inlet pressure range. 0 Page 54 of 148 8.2 Idle Speed and Idle Mixture Engine idle speed is adjusted so that the vehicle does not stall when stationary (too low) or consume excess fuel/jump when moving off (too high). Idle mixture is set to provide a good fuel/air combination (neither too rich and “loading up” at idle, nor too lean and stumbling) when stationary. Whilst idle speed and idle mixture can be set “by ear”, there are some tools that make it easier/more consistent: A tachometer (either dash mounted or fed from the ignition leads) can help accurately set idle speed. If a tachometer is unavailable, a timing light can be connected and the number of “flashes” in twelve seconds counted. Multiply the number of flashes by ten to get the RPM. This is pretty hard to do though – you are looking to count around four flashes per second. A vacuum gauge (either dash mounted or a removable pressure gauge that screws into the inlet manifold after disconnecting the vacuum wipers (FB and earlier Holdens) or power brake/windscreen washers (NASCO accessories) from the manifold. The vacuum gauge gives a more accurate setting to the idle mixture than the “back it off until it runs smooth” method. To set the idle speed and mixture: 1. 2. 3. 4. 5. Warm the car up to normal operating condition. Check the choke is off. Leave the air cleaner in place. On automatics, the transmission should be in DRIVE (D) with the handbrake firmly engaged. Fit the vacuum gauge to the inlet manifold and the tachometer (where available). Adjust the slow idle adjusting screw (54) until the engine idles at 480-520 rpm (check with a tachometer, timing light counting or “by ear”). If you have a vacuum gauge, adjust the idle needle valve (59) until you get the highest vacuum possible (this should be between 17”-21” Hg, or 60-70 kPa, or 8-10 psi). This can be difficult if the vehicle has a large cam (high valve overlap) as the vacuum at idle will fluctuate. In this case, adjust the idle needle valve (59) until the tachometer reads maximum rpm. If you don‟t have a vacuum gauge or tachometer, turn the idle needle valve (59) slowly inwards until the engine starts to run irregularly. Back the idle needle valve (59) outwards until the engine begins to “roll”, then inwards again until the engine runs smooth. Check the engine speed again, and repeat steps 3. and 4. above until a satisfactory idle is achieved. Remove the tachometer and vacuum gauge and refit any vacuum lines that were disconnected. 6. 7. If a rough idle persists after the mixture screws have been adjusted, check for vacuum leaks. These could result from unplugged vacuum fittings, carburettor flange gaskets that were torn during installation, cracked lines or loose bolt/screws. A quick way to check vacuum leaks is to spray WD40 in the suspected area with the engine running – if the engine speed increases, there is a vacuum leak. Whilst early Holdens, being manufactured prior to July 1972, are generally not required to comply with emission standards. However, from that date onwards, all petrol passenger vehicles (and derivatives) were required, when new, to comply with a performance standard (ADR) that set limits for exhaust emissions of hydrocarbons (HC), oxides of nitrogen (NOx) and carbon monoxide (CO): Page 55 of 148 ADR26 was introduced 1/1/1976, and captures the CO at idle test (limit of 4.5% maximum volume CO). ADR27, 27A, 27B and 27C applied to vehicles manufactured from July 1976 to January 1986. Vehicles made in this period generally ran on leaded petrol and employed carburettors. ADR37/00 covers the period from February 1986 to the present. Vehicles manufactured after January 1986 generally run on unleaded petrol (catalytic convertors), with computerized engine management systems, fuel injection. A summary of the emissions requirements of each of the tests above can be found here: http://www.infrastructure.gov.au/roads/environment/impact/emission.aspx. Most early Holdens will not have to conform to the above. However, some engineers request the CO at idle test when vehicles have been modified to the extent that they require an engineer‟s report. It is important to note that the idle test is normally done at idle (480-520rpm). There is an alternative “high idle” test, which is conducted at 2500rpm. This test, although usually not applied to early Holdens, will bring the main metering circuit into play (i.e. tuning for the CO at idle test is made via the idle needle valve (59), tuning for the “high idle test”, if it was ever applied, is by changing the main metering jet). To tune the idle circuit to meet a CO at idle test, an engine exhaust analyser is used – these are discussed more fully in Section 2.5.4 below. When tuning for emissions, a CO at idle reading of 1-3% should be targeted. Note that on vehicles with very lumpy cams, the large amount of valve overlap can mean that there is very little vacuum at idle (6”Hg or less). At times, these vehicles may not respond well to setting the idle mixture – the idle mixture screw seems to do little to help the idle. The low engine vacuum at idle means that the throttle plates need to be opened more than usual to draw fuel from the idle system… in fact they can be opened so much that the secondary idle discharge holes are uncovered, leading to excessively rich idle (and no control of the idle mixture as the idle needle valve only controls the lower idle discharge hole). To check for this, set the idle as best as possible, then remove the carburettor and check the throttle plate position – if one or more of the upper idle discharge holes is exposed, then this may be the 3 1 cause of the loss of idle control. One method to fix this is to drill a /32”- /8” hole in the throttle plate on the same side of the shaft as the idle discharge holes. The small hole will allow some air to pass, allowing the throttle plates to be closed further and idle mixture control regained. This condition should not be confused with an early opening power vacuum piston – see Section 8.8 below. 8.3 Accelerator Pump Stroke and Components The accelerator pump stroke can be checked for standard settings as follows (though this should not be necessary if it has been set on the bench during overhaul): 1. Start the vehicle and bring it to normal operating temperature and idle. This sets the correct throttle closed position. 2. Turn off the engine and remove the air cleaner, air cleaner and air horn from the carburettor. 3. Measure and record the distance from the top of the accelerator pump piston stem to the top face of the carburettor body (with the gasket removed). 4. Open the throttle fully and again check and record the distance. 5. The difference between the two measurements (which is the accelerator 13 15 pump stroke) should be /64”- /64”. If the difference is more or less than this range, the accelerator pump stroke can be changed by bending the top horizontal portion of the accelerator pump rod (24). Two bends are needed for each adjustment to keep the hole in the pump rod parallel with the pump stem. Page 56 of 148 The accelerator pump can also be tuned to give better throttle response. A larger or smaller engine will want more or less fuel added when the throttle is opened. Bear in mind that the accelerator pump is responsible for the initial acceleration only – most of the acceleration up to final speed is done by either the main metering or power circuits. The following table gives some guidance on observations seen when initially cracking the throttle (and assumes the accelerator pump, ignition and timing is in good working order): Observation Engine is lazy for a few seconds then begins accelerating (sometimes fluttery). Opening the throttle more slowly makes the issue go away. Puff of black smoke from exhaust that quickly clears. Opening the throttle more slowly makes the issue go away. Engine stumbles then begins accelerating. Engine backfires during accelerating. Cause Too much or too long of a pump squirt. Tuning Change to heavier pump stem spring or pack washers under spring. Too little or too short of a pump squirt. Change to lighter pump stem spring or cut portions of the spring coils away. The duration of the pump squirt is determined by three issues: the stiffness of the pump stem spring (25). Early Holdens up to EJ (including EK and EJ manuals) had spring number 7405169. This spring is copper coloured and heavier (to the point that it can hold automatic vehicles throttle part closed as per the Service Bulletin to the right). EK and EJ automatics had spring part number 7423236. This spring is cadmium plated and lighter. EH, HD and HR (excluding S engine) had 7424555. HR S engine had VS10488. It is possible to pack washers under the spring to increase the spring stiffness, or to carefully remove spring coils (say ½ a coil at a time) to reduce spring stiffness. the size of the pump bypass jet (27). All early Holdens used a No. 56 drill (0.0465”) accelerator pump bypass jet. Pump bypass jets are stamped with the jet size in drill number (e.g. a jet stamped 56 has a 0.0465” diameter hole drilled in it). In theory the pump bypass jet can be drilled out to a larger size (giving a faster pump squirt), though the drilling process would need to be very careful, as the area immediately behind the jet hole (marked by the red arrow in the diagram to the right) contains a small valve stem and spring which could readily be drilled through. A blind drill bit would be preferable…my guess is that finding a set of blind jet drills would be like finding rockinghorse poo. the size of the pump discharge nozzle. Grey motors used a No. 70 drill (0.0280”) discharge nozzle, EH/HD/HR red motors used a No. 72 drill (0.0250”). Note that the accelerator pump system has no air bleed – fuel is sent to the carburettor throat without being made into an emulsion. This means that the pump discharge nozzle has the task of atomizing the fuel. It does this by pressure drop over the nozzle – just like putting your finger over the end of the garden hose. Putting a bigger pump discharge nozzle into the carburettor (or drilling the existing one oversize) will cause more fuel to flow as the pump discharge nozzle is far smaller than the pump bypass jet (i.e. the discharge nozzle is a bigger Page 57 of 148 restriction). However, making the pump discharge nozzle bigger means that the fuel is not as well atomized – you may get more in, but it doesn‟t burn as well. The pump bypass jet (27) is a better tuning point (and easier to reverse if you choose too big a bypass pump jet). The volume of the pump squirt is determined by how far the pump piston and stem assembly (26) moves down the pump well bore. The accelerator pump on Stromberg BXOV-1 carburettors may also be adjusted by putting the pump link into one of the three different holes in the pump lever. Note that the FB Workshop Manual provides the following guidance: 9 “The capacity of the accelerator pump is correctly calibrated at the pump stroke of /32” and under no circumstances should the pump stroke be adjusted by shifting the pump link from the centre hole of the pump lever. The inner and outer holes in the pump lever provide too great a variance in the pump stroke and must result in reduced performance and economy”. Whilst some enthusiasts find that there is little feelable difference between the three holes when running single carburettors, changing hole settings may help more with multiple carburettors. I have measured the following info from a BXOV-1 carburettor using a dial run-out gauge - the table below gives the fuel delivery for the three pump link holes: Pump Link Setting Outer (furthest from throttle shaft pivot) Centre (middle) Inner (closest to throttle shaft pivot) 1.4 1.2 1.0 Pump Output (cc) 0.8 0.6 0.4 0.2 0.0 0 10 20 Throttle Shaft Rotation (o) 30 40 Delivery per stroke 1.2mL 0.87mL 0.3mL Outer Centre hole Inner From the chart above, the inner hole delivers a lot less fuel, and finishes doing so at a lower throttle shaft rotation. The centre and outer holes deliver more fuel, and do so over a wider throttle shaft rotation. Note o that at all settings, the accelerator pump finishes squirting (20-35 ) well before the throttle shaft finishes o turning (throttle shaft typically finishes at 65 ): Page 58 of 148 Throttle shaft rotation WOT 65o Outer setting35o Centre setting 33o Inner setting 20o Idle 0o 8.4 Idle Vent Valve Lift For BXUV-2 and BXV-2 carburettors, once the engine idle speed and accelerator pump stroke have been adjusted, the idle vent valve lift can be set. The following process is used: 1. Start the vehicle and bring it to normal operating temperature and idle. This sets the correct throttle closed position. Ensure that the choke is fully off (open). 2. Stop the engine and measure the vertical lift of the idle vent valve stem as the throttle lever is moved from the fully open to the fully closed position. 3. Hold the idle vent valve washer and screw the idle vent valve stem up or down until a lift of 0.0400.060” is achieved. Tighten the locknut. 4. Open and close the throttle several times then recheck the lift dimension. Repeat steps 2-3 until the correct lift is achieved. 8.5 Wide-Open Throttle (WOT) Adjustment The linkage between the accelerator pedal and throttle plate is a complex affair on FB/EK Holdens – there are eleven bearing points that can jam with old grease and dirt, a number of brackets and rods that can get bent over the last half decade, and plenty of opportunity for the message from your right boot to get mixed up before it gets to the carburettor. It is time well spent following through the linkage from the accelerator pedal through to the carburettor, giving each bearing point a clean up with a rag dipped in kerosene and a light dab of grease. Don‟t expect to find any fancy roller bearings – all the bearings here are simple metal rods swinging through holes in brackets. If the throttle linkage is not adjusted correctly, the carburettor will not open fully at full throttle, and top-end performance is reduced. To adjust the throttle linkage on manual vehicles: 1. Disconnect the pull back spring from the throttle control adjusting bracket. 1 3 2. Have an assistant hold the accelerator pedal just above the floor mat/carpet ( /8- /16”). 3. Loosen the throttle control adjusting bracket attaching bolt (coloured red in the diagram below), then pull the carburettor throttle lever by hand until the throttle plates are wide open (you can see this by looking down the carburettor throat). The throttle control adjusting bracket will move in an arc, up or down as required to obtain the correct adjustment. 4. Tighten the throttle control adjusting bracket attaching bolt securely. 5. Reconnect the pull-back spring. 6. Recheck the engine idle speed, as it is possible that the throttle plates have been pulled slightly more open. Page 59 of 148 Page 60 of 148 To adjust the throttle linkage on automatic vehicles: 1. Adjust the throttle control adjusting bracket (labeled “slotted bracket” in the diagram below) such that the end of the upper cross shaft lever is in the centre of the bracket slot. 2. Check that the underside of the pivot end of the upper cross shaft lever clears the welded body joint 3 by approximately /8” when the lever is in the fully returned position. If necessary, loosen the throttle control adjusting bracket lock nut and move the lever up or down to obtain this clearance. 3. Disconnect the throttle valve connecting rod at the linkage end. This rod is not shown in the diagram below, and connects a lever on the left hand side of the transmission case to the throttle linkage. 4. Depress the accelerator pedal slowly until the underside of the pedal just contacts the kick-down button on the floor. Check that the carburettor throttle valve is fully open without compressing the throttle over-travel spring. If necessary, loosen the locknut on the lower cross shaft rod and adjust the length of the rod as required. Tighten the locknut. 5. Reconnect the throttle valve connecting rod at the linkage end. 6. Check adjustment by road testing to ensure the transmission will kick-down into second gear only when the accelerator pedal is pressed through the kick-down detent position at a road speed of 40 mph. Minor adjustment of the lower cross shaft rod may be required, though major adjustment will require repeating steps 1-5 above and can indicate that the throttle valve lever on the transmission case is incorrectly set or the levers or rods are bent/worn. 7. After adjusting the throttle linkage, reset the idle speed with the engine in Drive. Note that the linkages on EJ, EH, HD and HR Holdens are different from the EK linkage shown above. Excellent diagrams and instructions can be found in The Scientific Publications Workshop Manual Series No. 67 Holden covering series 1948/‟53 FJ, FE, FC, FB, EK, EJ, EH, HD, HR for these vehicles. Page 61 of 148 8.6 Main Metering Jets The purpose of the main metering jet is to provide the correct air/fuel mixture under intermediatry throttle positions (“cruise”). Whilst the factory jet sizings are a good starting point (see table below), changes in fuel quality in the last fifty years (for example the increase in octane and the addition of ethanol) can make engines run considerably leaner than when they left the GMH factory. A lean fuel mixture (primary metering jets too small, too little fuel for the amount of air in the cylinder) may be seen by one of more of the following: a miss or stumble whilst cruising at constant throttle opening, a flat spot when you put your foot down part way (this may happen after split second when the initial squirt from the accelerator pump is used up), the engine runs hot… and if it is very lean, then the valves are burnt, the sparkplugs are white or very pale… and if it is very lean, the electrodes start to show signs of being eroded/burnt away (rapidly followed by engine valves and cylinder crowns…), power is reduced, and pulling the choke out slightly reduces the problem. A rich fuel mixture (primary metering jets too large, too much fuel for the amount of air in the cylinder) may be seen by one of more of the following: the engine surges at constant throttle, though there is no flat spot when the throttle's floored. if the mixture is way too rich it will cough and splutter until the throttle's held wide open under load (where the power bypass jet takes over). There can be a smell of unburnt fuel from the exhaust when it is held at mid-throttle. the spark plugs can be fouled and black, and the vehicle runs sluggishly. A number of main metering jets are available for Stromberg carburettors, both factory and aftermarket. Main metering jets are stamped with the jet size in thousandths of inches (e.g. a jet stamped 56 has a 0.056” diameter hole drilled in it). Of note: A range of main metering jets (typically 0.041”-0.068”) are held in stock by the Carburetor Service Company. I have extended the table below to show this range. I have listed below the main metering jets made by Stromberg Carburetor Ltd for Stromberg 97 carburettors. The Stromberg 97 (model EE-1) jets commonly available for the hotrodder market do fit the B series carburettors (for example 1942-1953 Fords and Mercurys fitted with Stromberg 97s used the exact same part number main metering jet as early Holdens, though in 0.043” and 0.044”). Note that Stromberg Carburetor Ltd are also able to supply customs sizes other than those listed below, though you must order through one of their dealers. Rocket Industries is the Australian dealer for Stromberg Carburetor Ltd, and stock the 0.041”, 0.043”, 0.045” and 0.047” main metering jets at the time of writing this document, and are able to ship in the other sizes in a weeks delivery time. Note that the Stromberg Carburetor Ltd jets are at the small (lean) end of the scale, and are more likely to be useful to those running twin or triple carburettors than those running singles. Whilst American Auto Parts lists twentysix main metering jets on their website ranging from 0.040”0.067”, they do not physically stock any of the jets at the time of writing this document. Where the correct size main metering jet is not available, it is possible to solder up a jet and redrill it to the correct size. This requires a very precise set of drill bits – to be honest, for most enthusiasts the effort involved to hunt down the right drill bit is equal to that of finding the right jet from the sources above. Jet drills in metric sizes are common (and very cheap at the time of writing this document via eBay). Fractional imperial drills in small sizes are a lot harder to find, but are available as a set from Rocket Industries (Part number BG130050, Barry Grant jet drills sizes #61 to #80 (0.135" to .039")) and as individual drills from Lee Brothers Engineering in Parramatta. When soldering jets, lead Page 62 of 148 solder is acceptable to use as the typical lead solder melting point is around 180ºC – petrol boils between about 20ºC and 210ºC… if the carburettor is hot enough to melt the solder, it‟s already boiling out most of the fuel. Care must be taken though as lead solder is very soft, and easily damaged. Silver solder (melting point above 450ºC) is somewhat harder. ← RICHER The table below provides some guidance for initial tuning (the bigger the main metering jet size, the more rich the engine runs): Stromberg GMH Part Carburetor Jet Size Standard for Number Ltd Part Number 0.033 9533K-33 0.034 9533K-34 0.035 9533K-35 0.036 9533K-36 0.037 9533K-37 0.038 9533K-38 0.039 9533K-39 0.040 9533K-40 0.041 9533K-41 0.042 9533K-42 0.043 9533K-43 0.044 9533K-44 0.045 9533K-45 0.046 9533K-46 0.047 9533K-47 0.048 0.049 0.050 VS10535 7403431 9533K-48 9533K-49 9533K-50 HR S high altitude 8000-12000 ft (186ci) 1 NOTE 0.051 7405264 VS10534 - 0.052 0.053 7420385 VS10533 - 48, 50, FJ (132.5ci) 48, 50, FJ, FE, FC (132.5ci) FB, EK, EJ (138ci) EH high altitude 8000-12000 ft, HD economy (149ci) HR high altitude 8000-12000 ft and economy (161ci) NOTE 1 HR S high altitude 4000-8000 ft (186ci) EH high altitude 4000-8000 ft (149ci) HR high altitude 4000-8000 ft (161ci) NOTE 1 HR S (186ci) Page 63 of 148 0.054 - - 0.055 7420388 - 0.056 0.057 0.058 0.059 0.060 0.061 0.062 0.063 0.064 0.065 0.066 0.067 0.068 7424569 VS10185 7420412 - - EH, HD (149ci) HR (161ci) EH high altitude 8000-12000 ft, HD economy and X2 (179ci) HR economy and X2 (186) EH high altitude 4000-8000 ft (179ci) EH, HD excluding X2 (179ci) HR excluding S and X2 (186ci) EH, HD excluding X2 (179ci) - NOTE1: HR 186S engines (WW Stromberg) have a different main metering jet to the B-Model Stromberg carburettors used in earlier Holdens (and Stromberg 97s). The 186S main 15 metering jet is /32” long overall, and can be further identified by a line 1 1 stamped under the jet size on the shank and a /32”x /64” groove cut into the shank (as per the image to the right). The earlier B-Model (and Stromberg 97s) Stromberg carburettors had main metering jets with an overall length of 33 /64” with no grooves cut in the shank (as per the image to the left). The metering orifice in the two types of jet are different, and produce different flow characteristics (e.g. the 0.051” main metering jet used in the EK Holden will flow differently to the 0.051” main metering jet used in the HR 186S engine high altitude 4000-8000 ft operation). This means that although you can use WW main metering jets in a B-Model carburettor, the range of the WW jets is different to the B-model ones – this can make things tricky when “stepping through the jet sizes” during tuning. The simplest way can be to make sure that all the jets you are “stepping through” are either all WW or all B-model. Changing the main metering jet is as simple as: stopping and letting the engine cool (as some fuel will be drained onto the inlet manifold), removing the main metering jet plug (44) with a stubby flat-head screwdriver (or the fancy tool that comes with some jet keys), removing the main metering jet (42) with a Stromberg jet key (or GMH tool 6A12) and screwing the new jet in, replacing the metering jet plug gasket (43) and reinstalling the main metering jet plug (44). There is also an aftermarket adjustable main metering jet (sometimes referred to as an adjustable main jet or adjustable jet, American Auto Parts SBP-039) available for Stromberg carburettors. The adjustable main metering jet is essentially a needle valve that screws into (and replaces) the original main metering jet plug. The adjustable main metering jet is used in conjunction with a special main metering jet that is much larger than the engine will ever need. The special jet (pictured in the lower left of the adjacent photograph) has a tapered seat to suit the needle – standard main jets have a square shouldered jet. In this case the special jet does not provide the restriction to do the metering – the needle valve does. Page 64 of 148 Adjustable main jets have their good points (you only need to buy one adjustable jet rather than several fixed jets to get the right one), together with their shortcomings (the temptation to fiddle with them or go hunting for better fuel economy can lead to over-lean conditions and burnt valves, the o-ring seal can leak over time). As an initial tuning point, the following may be used: bring the engine up to operating temperature, hold the engine speed at around 3000-3500rpm (mid throttle). Slacken the lock nut on the adjustable jet then screw the adjuster in slowly until the engine speed starts to alter and run a little bit rough. Wind back the adjuster until the engine speed pick up and the engine no longer runs rough. Tighten the lock nut. There are a number of ways to select the correct main metering jet (or correctly adjust an adjustable main metering jet): reading the spark-plugs, measuring exhaust gas carbon monoxide, and running the car on a dyno/strip (more applicable to the power bypass jet – see section 2.5.5 below). Each of these methods should be undertaken in conjunction with road testing, looking for stumbles, flat spots, drivability and fuel consumption. Reading the colour of the spark plug electrodes (and to a lesser extent the colour of the exhaust pipe) provides a cheap and easy guide to correct main metering jet choice. This technique involves driving the vehicle for a run (up to operating temperature and a moderate distance at “cruise” conditions – not all at idle or full throttle!). After stopping then cooling down the engine, each plug is removed in turn and the colour of its electrode compared. Today the use of unleaded fuels and high-energy ignition systems has made this method much harder because very little color is seen on the spark plug; however the pictures below give some guidance: Overly lean (main metering jet is too small). Whitish or pale deposits. May also be seen by erosion of the spark plug electrode or detonation damage of the insulator. Correct jetting: electrode deposits are slight and not heavy enough to cause any detrimental effect. Colour is brown to greyish tan colour, and minimal amount of electrode erosion. Overly rich (main metering jet is too large): Soft, black, sooty deposit. A more full description of spark plug http://www.classiccarhub.co.uk/articles/spark_plugs.html. readings can be found at Page 65 of 148 A much more accurate way to tune the main metering jets is to measure the carbon monoxide (CO) in the vehicle exhaust. CO is one of the gases in the engine exhaust (along with nitrogen (N2), carbon dioxide (CO2), water (H2O), hydrocarbons (unburnt fuel, often written as HC), and various nitrogen oxides (NOX) and sulphur oxides (SOX). The amount of CO in a vehicle exhaust is an indicator of the air/fuel mixture being supplied to the engine, and thus is an excellent way of tuning jet sizes on carburettors. Manufacturers typically specify a CO level somewhere within the range 0.5% to 3.5% by volume. At CO levels higher than this there is a loss in economy, and at very rich settings, typically 8% to 10% CO, the onset of poor running occurs, characterized by the particular engine sound that is known as “hunting”. It should be noted that an engine, even in good overall condition, will show a fluctuation in idle CO over a period of time, of typically 0.5%. To measure CO, a sample probe is placed into the exhaust pipe and an exhaust gas analyser unit “reads” the CO in the exhaust. The other readings that some exhaust analyzers provide include HC (the best mixture gives you the lowest HC), CO 2 (the best mixture gives you the highest CO2 reading) and O2. Whilst workshop units can cost in excess of $4000, a simple and cost effective exhaust analyser (the “Gastester Digital”) is available from Gunsen for around $250 (see http://www.gunson.co.uk/item.aspx?item=1835). This would not be a bad investment if you are planning to tune a few early Holdens over the years. Using this analyser, some starting points for tuning would be to tune to 0.75-1.25% CO (1–3% CO for a lumpy-cammed engine) at cruise conditions. 8.7 Power Bypass Jets The purpose of the power bypass jet is to provide the correct air/fuel mixture under heavy throttle positions (towing, moving up hills or racing). Whilst the factory jet sizings are a good starting point (see table below), changes in fuel quality in the last fifty years again makes for some tuning change. A number of power bypass jets are available for Stromberg carburettors, both factory and aftermarket. Power bypass jets are stamped with the jet size in drill number (e.g. a jet stamped 56 has a Nº.56 drill or 0.0465” diameter hole drilled in it). Of note: I have listed below the power bypass jets made by Stromberg Carburetor Ltd for Stromberg 97 carburettors. The Stromberg 97 (model EE-1) power bypass jets commonly available for the hotrodder market do fit the B-Model carburettors. The only difference is that the head of the B-model jet is 0.407” diameter, whilst the head of the Stromberg 97 (EE-1) jet is 0.395” diameter (see image to the right). Despite the slightly smaller head, the Stromberg 97 power bypass jet seats well in the B-Model body. Note that Stromberg Carburetor Ltd are also able to supply customs sizes other than those listed below, though you must order through one of their dealers. Rocket Industries is the Australian dealer for Stromberg Carburetor Ltd, and stock the Nº.69 power bypass jet at the time of writing this document. Rocket Industies are able to ship in the other sizes in a weeks delivery time. Note that the Stromberg Carburetor Ltd jets are at the small (lean) end of the scale, and are more likely to be useful to those running twin or triple carburettors, or for single carburettored grey motors rather than for red motors. In theory the power bypass jet can be drilled out to a larger size (giving a richer mixture under load), though the drilling process would need to be very careful, as the area immediately behind the jet hole (marked by the red arrow in the diagram to the right) contains a small valve stem and spring which could readily be drilled through. A blind drill bit would again be preferable…my guess is that finding a set of blind jet drills would be like finding rockinghorse poo. The table below provides some guidance for initial tuning (the bigger the main metering jet size, the more leaner the engine runs – this is the opposite of main metering jets!): Page 66 of 148 Jet Size 54 55 Diameter 0.0550” 0.0520” GMH Part Number 7424565 7420747 Stromberg Carburetor Ltd Part Number - Standard for EH (179ci) EH, HD excluding X2, HR (179ci) HR excluding X2 and S (186ci) EH, HD, HR (149ci) HR (161ci) HD normal and economy excluding X2 (179ci) HR X2 and economy (186ci) EH (149ci) 56 0.0465” 7420490 - ← LEANER 57 58 59 60 61 62 63 64 0.0430” 0.0420” 0.0410” 0.0400” 0.0390” 0.0380” 0.0370” 0.0360” 7424564 - - 9594K60 9594K61 9594K62 9594K63 9594K64 48, 53 (132.5ci) FB, EK, EJ (138ci) HD economy (149ci) HR economy (161ci) FJ, FE, FC (132.5ci) - 65 0.0350” 7406899 9594K65 66 67 68 69 70 71 0.0330” 0.0320” 0.0310” 0.0292” 0.0280” 0.0260” - 9594K66 9594K67 9594K68 9594K69 9594K70 9594K71 Note that whilst it appears that the HR Holden 186S (WW-Model) power bypass jet is interchangeable with the early B-Model (and hence Stromberg 97) power bypass jets, the HR Holden valve has two Nº.56 drill (0.0465”) holes (i.e. much larger capacity) than the B-model single-hole power bypass valves. For those seeking dual-hole WW power bypass jets, it is likely that Stromberg Carburetor Ltd (via Rocket Industries) could supply a double-drilled jet. Changing the power bypass jet is a little more complicated than changing a main metering jet. The process is as follows: 1. Remove the air cleaner wingnut, air cleaner lid and filter element. Slacken off the slot-head bolt under the filter base then remove the base. 2. Slacken off the choke tube clamp screw (5) and choke wire clamp screw (3). Pull the choke cable out from choke tube holder assembly (7). Leave the choke cable hanging from the firewall. Page 67 of 148 3. 4. 5. 6. 7. Remove the cotter pin (not numbered in the drawing above) from the lower end of the fast idle rod (18) then remove the rod. Undo the five flat-head air horn attaching screws and lockwashers (10A) and the choke tube holder attaching screw and lockwasher (10). Note that 10A and 10 are very similar – 10 is slightly longer to allow for the thickness of the choke tube holder. Lift off the air horn assembly (16). Using a large flat bladed screwdriver, unscrew and remove the power bypass jet assembly (21) and the associated gasket (22) from the main body (37). Screw the new power bypass jet assembly and gasket in place. Reverse the above steps to reassemble the air horn. One method to tune the power bypass jet is to use timed acceleration runs (e.g. ¼-mile times), or top speed/power (e.g. dyno-tuning). This involves trial and error jetting changes to obtain the best results, and needs some moderate track or dynamometer time to get decent repeatable results. An easier way is to again tune using an exhaust analyser (particularly if you have the Gunson exhaust analyser described in Section 2.5.4 above). Some starting points for tuning would be to tune to 6.6% CO under load conditions. Whilst this could be reduced to 4% for engines with very good combustion chamber design, early Holden cylinder heads rarely meet this criteria. 8.8 Vacuum Power Piston Whilst the Stromberg B-Model power bypass jet is readily able to be tuned for flow (bigger or smaller power bypass jet orifices), it is harder to tune for when (or at what vacuum) it opens. The standard vacuum power piston opens at 6”Hg. For most early Holden applications, there is approximately 17-21”Hg of vacuum at idle, meaning that the power bypass jet is well and truly shut at idle (as it should be). However, vehicles with a large overlap (lumpy) cam can idle at 6” Hg or lower. At this vacuum, the power bypass jet can open and will start to feed the mixture, leading to the vehicle “loading up” at idle. For these engines, a power valve is required that opens at lower vacuum. Whilst it is possible to disassembly the vacuum power piston (say to fit a lighter spring), the main stem has a very heavy swage that holds the assembly together. The photo to the right shows the stem swage (circled in red), which is visible after tapping out the covering cap (seen to the lower right of the image). The swage would be very difficult to remake when reassembling - it is likely that the stem would be inadvertently bent, rendering the piston useless. A pin is also possible (by cross-drilling the main stem), though not very practicable as the swage/pin would need to fit into the (fairly tight) piston recess. The simplest option is to modify the existing spring in-situ. To lower the vacuum setting (e.g. from the standard 6”Hg to 4”Hg), the spring in the power piston is shortened. To shorten the spring: 1. Set the idle mixture as described in 8.2 above. Check that the idle upper discharge holes have not been uncovered at idle (i.e. that the secondary idle system is not the source of the excess fuel at idle) in line with the guidance in 8.2 above. 2. Ensure that the vehicle main metering jets are reasonably sized and not the cause of the overrichness at cruise. This may be done by placing a few small washers on top of the power bypass jet to prevent the vacuum power piston from depressing the pin, then checking the exhaust gas quality under cruise conditions (see 8.6 above). Remove the washers and refit the air horn assembly. Check that the exhaust gas quality now runs very rich again under idle conditions. Having ruled out the idle and main metering systems as the source of excess fuel, shorten the spring: 3. Remove the air cleaner wingnut, air cleaner lid and filter element. Slacken off the slot-head bolt under the filter base then remove the base. 4. Slacken off the choke tube clamp screw (5) and choke wire clamp screw (3). Pull the choke cable out from choke tube holder assembly (7). Leave the choke cable hanging from the firewall. Page 68 of 148 5. Remove the cotter pin (not numbered in the drawing above) from the lower end of the fast idle rod (18) then remove the rod. 6. Undo the five flat-head air horn attaching screws and lockwashers (10A) and the choke tube holder attaching screw and lockwasher (10). Note that 10A and 10 are very similar – 10 is slightly longer to allow for the thickness of the choke tube holder. 7. Lift off the air horn assembly (16). 8. Remove the vacuum power piston using a pair of circlip pliers and carefully trim a single coil from the spring with a pair of sidecutters. 9. Refit the vacuum power piston and refit the air horn assembly. Check that the exhaust gas quality, and repeat the trimming steps until the vehicle returns to a reasonable idle quality. 10. Repeat steps 3-9 for cruise conditions if the vacuum is sufficiently low to allow the power bypass jet to open at cruise. Note that it is also possible to increase the vacuum setting at which the vacuum power piston will open. This may be done to match the springs in multiple carburettor setups such that all carburetors open at the same vacuum. Increasing the vacuum setting is achieved by fitting brass washers under the spring, making the spring stiffer. To do this, 1. Remove the air cleaner wingnut, air cleaner lid and filter element. Slacken off the slot-head bolt under the filter base then remove the base. 2. Slacken off the choke tube clamp screw (5) and choke wire clamp screw (3). Pull the choke cable out from choke tube holder assembly (7). Leave the choke cable hanging from the firewall. 3. Remove the cotter pin (not numbered in the drawing above) from the lower end of the fast idle rod (18) then remove the rod. 4. Undo the five flat-head air horn attaching screws and lockwashers (10A) and the choke tube holder attaching screw and lockwasher (10). Note that 10A and 10 are very similar – 10 is slightly longer to allow for the thickness of the choke tube holder. 5. Lift off the air horn assembly (16). 6. Remove the vacuum power piston. Compress the spring with your fingers and temporarily hold it in place with a cable tie. This prevents the spring being damaged whilst manipulating the washers below. 1 7. Take a /8” brass washer (I have used Zenith EBG4003‟s here from Bunnings), and cut the washer on one side. Bend the washer open like a spring washer. 8. Fit the bent brass washer to the vacuum power piston shaft and bend it back into shape, taking care that the washer cut closes. 9. Refit the vacuum power piston and refit the air horn assembly. Check that the exhaust gas quality, and repeat the addition of washers until the desired opening point is achieved. The following table gives some guidance as to how the vacuum setting will change with various modifications to the vacuum power piston spring on BXOV-1 carburettors (the changes will be slightly different for the BXOV/BXUV carburettors installed from mid-EH Holden onwards which had a longer vacuum power piston): Page 69 of 148 Spring Change 6 coils removed 5 coils removed 4 coils removed 3 coils removed 2 coils removed 1 coil removed Standard 3 /32” thickness of washers added 3 /16” thickness of washers added Vacuum Setting (“Hg) 1.5 2.5 3.5 5 5.5 6 6 7 12 For vehicles that run wide-open throttle most of the time (like HQ Holden circuit racers), the Stromberg power valve is often removed (blanked off) and the main jet sizes increased to suit. Whilst this is suitable for full throttle performance, it will lead to a very rich “cruise” condition and is not recommended for street use. 8.9 Troubleshooting It is common knowledge that “carburettor” is French for “don‟t F%@# with it”. Many Australian children have learnt to swear from listening to the carefully phrased epithets gently wafting from the open bonnet of an early Holden. The guidance below may assist in hunting down the cause of early Holden Stromberg issues (and perhaps prevent your children from developing their vocabulary). Of note, many ignition and timing issues are found to be the real cause of what is perceived to be a “bad carby” – the following table assumes all electrical and timing issues have been resolved. Fault Part to Check Float needle and seating Float Carburettor flooding Fuel level Fuel pump Condition to Look For Worn or dirt on seat. Punctured or damaged. Too high. Pressure too high. Remedy Replace or clean the float needle and seating. Replace the float. Reset to correct float level (bench) or fuel level (on-vehicle). Service the fuel pump, or check that replacement electrical pump pressures are compatible (4½ psi maximum). Clear the main metering jet and idle tube by: Remove the air filter assembly. Start the vehicle and allow it to warm up to operating temperature. Place your hand over the top of the carburettor air horn, and give the vehicle a number of full-throttle revs (don‟t panic… it won‟t suck you hand in!). Remove your hand and refit the air cleaner. , otherwise disassemble to clear. Tighten the main metering jet plug and pump check valve plug. Replace the copper washers if leaks persist. Difficulty cold starting Main metering jet and idle tube Obstructed. Float bowl Dripping/weeping, leading to empty float bowl on Page 70 of 148 startup. Float needle and seating Fuel pump Fuel line (fuel tank to pump) Sticking closed. Fuel pressure and volume insufficient. Leakage. Not closing fully due to: Bent choke shaft. Choke valve rubbing on air horn. Choke shaft bearing areas coked (carboned) up. Air horn distorted. Choke cable (wire) not connected or snapped. Automatic choke valve not closing correctly (HR 186S engines only) Replace the float needle and seating. Service the fuel pump. Tighten all unions and replace them if leaks persist. Replace the choke shaft. Slacken the securing screws slightly and centralize the valve plate. Clean away the coke. Replace the air horn. Tighten or replace the choke cable (wire). Choke valve Check for free travel and good condition of all parts. Check and reset the thermostat and all other automatic choke settings. Find the leaking gasket by spraying WD40 around the gaskets with the engine running (a cold engine will decrease the risk of the WD40 igniting off hot surfaces). Engine speed increases when WD40 is sprayed around leaking gaskets. Tighten nuts and replace gaskets if the leaks persist. Install a new baffle plate. Clear the idle tube by: Remove the air filter assembly. Start the vehicle and allow it to warm up to operating temperature. Place your hand over the top of the carburettor air horn, and give the vehicle a number of full-throttle revs (don‟t panic… it won‟t suck you hand in!). Remove your hand and refit the air cleaner. , otherwise disassemble to clear. Replace with the correct type idle tube. Ensure the float is not punctured or damaged. Reset to the correct float level (bench) or fuel level (on-vehicle). If the level builds up, check the float needle and seating and the fuel Carburetor flange and inlet manifold gaskets Air leaks. Float chamber baffle plate (HR 186S engines only) Baffle plate missing. Difficulty hot starting Idle tube Obstructed. Incorrect type Fuel level Too high. Page 71 of 148 pump pressure (4½ psi maximum). Idle vent valve (BXUV-2, BXV-2 and WW carburettors only) Incorrect opening Set the idle vent valve to the correct lift. Not opening fully due to: Bent choke shaft. Choke valve rubbing on air horn. Choke shaft bearing areas coked (carboned) up. Air horn distorted. Choke lever return spring broken. Choke cable (wire) not connected or snapped. Choke cable too short. Automatic choke valve not opening correctly (HR 186S engines only) Replace the choke shaft. Slacken the securing screws slightly and centralize the valve plate. Clean away the coke. Replace the air horn. Replace the choke return spring. Choke valve Tighten or replace the choke cable (wire). Adjust the choke cable to allow /8” slack in the cable when choke is fully open. Check for free travel and good condition of all parts. Check and reset the thermostat and all other automatic choke settings. Ensure the hot air pipe is not loose, blocked or broken. Replace the thermostat cover gasket and tighten the cover screws securely. Check that the throttle body hot air vacuum hole is clear. Clear the idle tube by: Remove the air filter assembly. Start the vehicle and allow it to warm up to operating temperature. Place your hand over the top of the carburettor air horn, and give the vehicle a number of full-throttle revs (don‟t panic… it won‟t suck you hand in!). Remove your hand and refit the air cleaner. , otherwise disassemble the idle tube to clear. Replace with the correct type idle tube. Replace the idle tube (all Models). Tighten the idle tube securely (B-Model carburettors) Clear the obstruction, taking care not to enlarge the idle bleed hole. Clear the idle discharge holes by: Remove the air filter assembly. 1 Obstructed. Idle tube Poor idling Incorrect type Not seating at shoulder (BModel) or collar near head of tube (WW-model). Carboned up or obstructed. Obstructed. Idle air bleed Idle discharge holes Page 72 of 148 Start the vehicle and allow it to warm up to operating temperature. Place your hand over the top of the carburettor air horn, and give the vehicle a number of full-throttle revs (don‟t panic… it won‟t suck you hand in!). Remove your hand and refit the air cleaner. Otherwise manually clear the obstruction, taking care not to enlarge the idle discharge holes. Idle restrictor rod (BXUV-2 and BXV-2 carburettors) Idle restrictor rod missing. Install an idle restrictor rod. Find leaking bearing areas by spraying WD40 around the outside of the air horn with the engine running (a cold engine will decrease the risk of the WD40 igniting off hot surfaces). Engine speed increases when WD40 is sprayed around leaking bearing areas. Rebush the worn bearing areas. Replace the throttle shaft. Find the leaking gasket by spraying WD40 around the gaskets with the engine running (cold engine will decrease the risk of the WD40 flashing off). Engine speed increases when WD40 is sprayed around leaking gaskets. Tighten the flange nuts and replace the gaskets if leaks persist. Clean the throttle body bore. Clean the throttle valve. Slacken the securing screws slightly and centralize the valve plate. Replace the idle needle valve. Adjust to the correct setting. Ensure the float is not punctured or damaged. Reset to the correct float level (bench) or fuel level (on-vehicle). If the level builds up check the float needle and seating and the fuel pump pressure (maximum 4½ psi). Replace the air horn gasket and tighten the securing screws evenly. Replace the throttle body to main body gasket. Tighten the throttle lever shaft nut. Set the idle vent valve to the correct lift. Throttle shaft bearing areas Worn and leaking air. Throttle shaft Worn. Carburetor flange and inlet manifold gaskets Air leaks. Throttle body bore Throttle valve Carboned up. Carboned up. Throttle valve rubbing on throttle body. Bent or damaged taper. Incorrectly set. Too high or too low. Not sealing idle passages and vacuum channels. Not sealing idle passage. Loose on shaft. Incorrect opening Idle needle valve Fuel level Air horn gasket (HR 186S engine only) Throttle body to main body gasket Throttle lever Idle vent valve (BXUV-2, BXV-2 and WW Page 73 of 148 carburettors only) Choke kick diaphragm and connecting hose (HR 186S engines only) Dashpot (HR 186S engines only) Leaking. Replace the diaphragm or hose. Accelerator pump piston Accelerator pump piston spring Accelerator pump linkage and throttle linkage Accelerator pump stroke Poor acceleration and flat spots Plunger clearance incorrect, dashpot plunger misaligned. Piston leather worn, creased, too hard, too soft or loose on shaft. No or little fuel is seen in carburettor throat when throttle is pressed. Insufficient or excessive tension. Worn (sloppy), allowing lost motion. Incorrect stroke. Obstructed by dirt or not seating. No or little fuel is seen in carburettor throat when throttle is pressed. Not seating, corroded or incorrect size. No or little fuel is seen in carburettor throat when throttle is pressed. Nozzle obstructed. No or little fuel is seen in carburettor throat when throttle is pressed. Leaking nozzle gasket. No or little Set the plunger clearance to specifications correct plunger alignment. Replace the accelerator pump piston. Replace the accelerator pump piston spring. Replace the worn parts, or fit a Fuelmiser Lost Motion Spring. Reset the pump stroke to the correct measure (bench or in-vehicle). Ensure the pump link is on the correct (middle) hole of pump lever. Accelerator pump intake check valve Clean or replace the accelerator pump intake check valve. Accelerator pump bypass valve Replace the accelerator pump bypass valve. Accelerator pump nozzle (HR 186S engines only) Clean or replace the accelerator pump nozzle. Replace the accelerator pump nozzle gasket. Page 74 of 148 Accelerator pump jet (BModels) fuel is seen in carburettor throat when throttle is pressed. Obstructed pump channels. No or little fuel is seen in carburettor throat when throttle is pressed. Obstructed. No or little fuel is seen in carburettor throat when throttle is pressed. Clean the accelerator pump channels. Clear the accelerator jet and pump channel with air pressure. Idle tube Partially obstructed. Idle discharge holes Obstructed. Idle mixture setting Main metering jet Vacuum power piston Power bypass jet Fuel level Automatic choke valve (HR 186S Too lean. Wrong size or obstructed. Worn, damaged or stuck in the up position. Obstructed or corroded. Too low. Not opening correctly. Clear the idle tube by: Remove the air filter assembly. Start the vehicle and allow it to warm up to operating temperature. Place your hand over the top of the carburettor air horn, and give the vehicle a number of full-throttle revs (don‟t panic… it won‟t suck you hand in!). Remove your hand and refit the air cleaner. Otherwise disassemble and clear the idle tube with air pressure or replace. Clear the idle discharge holes by: Remove the air filter assembly. Start the vehicle and allow it to warm up to operating temperature. Place your hand over the top of the carburettor air horn, and give the vehicle a number of full-throttle revs (don‟t panic… it won‟t suck you hand in!). Remove your hand and refit the air cleaner. Otherwise manually clear the obstruction, taking care not to enlarge the idle discharge holes. Adjust the idle mixture screw to give a richer setting (screw them out). Replace the main metering jet. Replace the vacuum power piston. Clear the obstruction or replace the power bypass jet. Reset to correct the float level (bench) or fuel level (on-vehicle). Check for free travel and good condition of all parts. Check and reset the thermostat and all Page 75 of 148 engines only) Multiple carburettors Air cleaner Throttle valve Fuel supply Not synchronized. Oversized venturi. Choked (blocked). Not opening fully. Insufficient. Main metering jet Obstructed, wrong size or type, damaged. other automatic choke settings. Ensure the hot air pipe is not loose, blocked or broken. Replace the thermostat cover gasket and tighten the cover screws securely. Check that the throttle body hot air vacuum hole is clear. Synchronise the carburettors. Fit a smaller venturi carburettor pair or install venturi sleeves. Clean the air filter element, or replace the element if it is the dry element type. Adjust the throttle linkage. Clear any obstructions in the fuel lines and check the fuel pump for correct delivery volume and pressure. Clear the main metering jet by: Remove the air filter assembly. Start the vehicle and allow it to warm up to operating temperature. Place your hand over the top of the carburettor air horn, and give the vehicle a number of full-throttle revs (don‟t panic… it won‟t suck you hand in!). Remove your hand and refit the air cleaner. Otherwise manually clear the obstruction, taking care not to enlarge the main metering jet hole or replace the jet. Replace the main discharge jet. Main discharge jet Lack of maximum speed or power High speed bleeder Vacuum power piston Power bypass jet Fuel level Damaged tip, crushed or enlarged side holes. Enlarged high speed bleeder hole. Stuck in the up position. Incorrect size, corroded or obstructed. Too low. Not opening due to: Bent choke shaft. Choke valve rubbing on air horn. Choke shaft bearing areas coked (carboned) up. Air horn distorted. Choke lever Replace the high speed bleeder. Clean the vacuum power piston and bore. Replace the vacuum power piston if damaged. Do not lubricate the vacuum power piston or bore. Replace the power bypass jet. Clear the power bypass jet passage with air pressure. Reset to the correct float level (bench) or fuel level (on-vehicle). Replace the choke shaft. Slacken the securing screws slightly and centralize the valve plate. Choke valve Clean away the coke. Replace the air horn. Replace the choke return spring. Page 76 of 148 return spring broken. Choke cable too short. Automatic choke valve (HR 186S engines only) Not opening correctly. Adjust the choke cable to allow /8” slack in the cable when the choke is fully open. Check for free travel and good condition of all parts. Check and reset the thermostat and all other automatic choke settings. Ensure the hot air pipe is not loose, blocked or broken. Replace the thermostat cover gasket and tighten the cover screws securely. Check that the throttle body hot air vacuum hole is clear. Replace the gaskets and washers and tighten unions. Tighten the idle tube. Replace the main metering jet. 1 Carburettor, fuel lines and fuel tank Idle tube Main metering jet. Leakage. Loose in body. Wrong size, wrong type or damaged. Damaged tip, bad top shoulder seat, bad seat with main metering jet, side holes crushed or obstructed. Obstructed. Main discharge jet. Replace the main discharge jet. High speed bleeder. Fuel level. Too high. Clear the high speed bleeder with air pressure or replace. Ensure the float is not punctured or damaged. Reset to the correct float level (bench) or fuel level (on-vehicle). If the level builds up check the float needle and seating and fuel pump pressure (maximum 4½ psi). Excessive fuel consumption Vacuum power piston. Power bypass jet. Accelerator pump link Idle vent valve (BXUV-2, BXV-2 and WW carburettors only) Choke valve Worn, damaged spring, stuck in the down position, blockage in vacuum channel, PVC tape left on vacuum passage following fuel level check. Wrong size, valve not seating, washer defective or missing. In furthest pump lever hole (pump stroke too long) Replace the vacuum power piston. Clear the channel. Replace the power bypass jet and washer. Place the pump link in the centre hole of the pump lever. Incorrect opening Set the idle vent valve to the correct lift. Not opening due Page 77 of 148 to: Bent choke shaft. Choke valve rubbing on air horn. Choke shaft bearing areas coked (carboned) up. Air horn distorted. Choke lever return spring broken. Choke cable too short. Replace the choke shaft. Slacken the securing screws slightly and centralize the valve plate. Clean away the coke. Replace the air horn. Replace the choke return spring. Adjust the choke cable to allow /8” slack in the cable when the choke is fully open. Check for free travel and good condition of all parts. Check and reset the thermostat and all other automatic choke settings. Ensure the hot air pipe is not loose, blocked or broken. Replace the thermostat cover gasket and tighten the cover screws securely. Check that the throttle body hot air vacuum hole is clear. Synchronise the carburettors. Fit a smaller venturi carburettor pair or install venturi sleeves. 1 Automatic choke valve (HR 186S engines only) Not opening correctly. Multiple carburettors Not synchronized. Oversized venturi. Page 78 of 148 9 Bigger Stromberg Swap There are some engine combinations where the original single-barrel Stromberg carburettor becomes restrictive. It is common practice for enthusiasts to go hunting for a larger carburettor in the search for more power. Carburettors are often rated in terms of the amount of fuel/air mixture they can flow at a given manifold vacuum. The flow rate is expressed in cubic feet per minute, or CFM. Care needs to be taken though in that a given carburettor may have several different venturi sizes, and hence several 1 3 different flowrates (for example the BXUV-2 carburettor was offered in both /32” and /32” venturi sizes for early Holdens). The manifold vacuum used to measure flow rate also varies. Some early published ratings for 1-barrel (e.g. B –Model Stromberg) and 2-barrel (e.g. WW-Model Stromberg) carburetors were measured at 3” Hg. 4-barrel carburettors (for example Holley 4150 carburettors) were rated at 1½”Hg. The table below has been compiled from information on multiple websites. I have converted the Quadrajet, Weber, and SU values to 3”Hg (they were published at 1.5”Hg). I have taken a single published figure for Stromberg BXOV-2 carburetors (210CFM) and converted to the smaller BXOV-1 and BXUV-2 carburettors by calculation based on the venturi and throttle bore diameters. The upshot of the above is that the table below is very approximate, but should give some indication of the relative flowrate achievable with different carburettors. Carburettor Weber 38-DGAS Rochester Quadrajet Mikuni 44 PHH Holley 7448 (“350 Holley”) SU HIF6 Weber 28/36-DCD SU HS6 Stromberg BOV-2 (the “big brother swap”) WW Stromberg Weber 32/34-DMTL Weber 32/36-DGV Weber 32/36-DGV Stromberg BXV-2 Stromberg BXUV-2 SU HS4 SU H4 Holley EGC Stromberg 48 Stromberg BXOV-1 Holley 94/8ba Stromberg LZ SU H2 Holley 94/59 Stromberg 97 Holley 92 Stromberg 81 Barrels 2 4 2 2 1 2 1 1 2 2 2 2 1 1 1 1 2 2 1 2 2 1 2 2 2 2 28 Venturi diameter 36mm/36mm 2¼ “/1.35” 37mm/30mm choke 3 3 1 /16”/1 /16” Variable 26mm/27mm Variable 1 /32” 1 /32”/ 1 /32” 26mm/27mm 26mm/27mm 23mm/27mm 5 1 /32” 3 1 /32” Variable Variable 1 1 1 /16”/ 1 /16” 1 1 1 /32”/1 /32” 3 1 /32” 15 15 /16”/ /16” 1”/1” Variable 15 15 /16”/ /16” 31 31 /32”/ /32” 7 7 /8”/ /8” 13 13 /16”/ /16” 28 9 Flowrate (CFM @3”Hg) 600 530 422 350 339 317 297 287 280 274 270 235 210 201 201 188 185 175 162 162 160 156 155 150 142 135 I will focus here on fitting larger Stromberg carburettors. The BXOV-1 Stromberg fitted to Holden grey motors is very similar in design and operation to those fitted to later red motors. It is tempting to fit a later 1 (and bigger) BXV-2, BXUV-2, or larger Stromberg carburettor - venturi sizes start at 1 /32" (grey motors), 3 5 7 and move through 1 /32" (149ci and 161ci red motors) and 1 /32” (173ci, 179ci and 186ci motors) to 1 /32” (202 motors). Note that these are not hard and fast rules though as there are some small venturis used Page 79 of 148 on larger motors (for example HR and HK 161ci taxi engines used 1 /32” venturis). Fitting a larger Stromberg carburettor can lead to better open-road performance on a standard grey motor, and is often done where racing vehicles need to comply with class requirements. For example: the current CAMS Group Na rules require carburettors to be of the make and model originally available pre-1958, though bore size is free. CAMS Group Nb (the old Appendix J and Group N class) rules allow later models of carburettors which were available in the period pre-1965 to be used, even with different throat sizes, provided that the outward appearance is the same. 5 Australian Speedway Lightning Sprints may use two single barrel Stromberg carburettors of 1 /32” venturi which must be externally stock standard though may be converted to methanol internally. The following provides some guidance for swapping to a larger Stromberg carburettor: 3 Care needs to be taken in that the bolt spacing for the BXOV-1 carburettor (2 /8”) is 11 different from that of the BXUV-2 and BXV-2 carburettors (2 /16”). The standard grey motor inlet manifold can be removed and the studs ground off. The manifold is then drilled and tapped to suit the larger bolt spacing. An alternative method is to make a spacer plate and use offset studs. 5 The BXOV-1 throttle bore diameter (1 /16”) is identical to that of the BXUV-2 7 carburettor, but smaller than the BXV-2 carburettor (1 /16”). The centre of the standard grey motor manifold will need to be ground out to meet the increased throttle body bore if using the BXV-2 or larger carburettors. Care needs to be taken that the gaskets used match up to the new bore size – no use having a large bore carburettor if it‟s trying to breathe past a tiny gasket hole. The stock inlet manifold can be made to breathe easier by splitting the manifold lengthwise across the flanges and grind out the centre of the manifold. The manifold is then furnace brazed back together. This was an old production class racing trick used when Holden inlet manifolds were class mandated. Moving to a larger Stromberg carburettor means that the carburettor will need to be re-tuned in its new home – the stock idle settings and jets may not be applicable to the smaller motor, and may need to be downsized to get a reasonable tune. There is a “big brother” swap that has been used in some dedicated race 9 vehicles. This utilizes the Ford Stromberg with 1 /32” venturis from 250ci 1V Ford motors (later 250ci 2V crossflow motors used twin-venturi Strombergs and Webber carburettors). Some caution is needed in fitting a carburettor this big to a grey motor – the Ford carburettor was originally designed for vehicles with almost double the cylinder capacity of the Holden grey. Serious headwork, valve train, exhaust (and the accompanying bottom end to stop it all grenading) is required to run the “big brother” single Stromberg carburettor. Whilst I‟m no Ford expert, Falcon XA/XB (and maybe XY) and Cortina TC/TD 250ci 1V engines (lower right image) were BOV-2 type. These have a “normal” flange (not a cross-flange like the BXOV-1), and put the linkage in an awkward position for the standard grey motor manifold (not to mention running the float north-south, where acceleration surge will play with fuel level). The Falcon XC, XD and TD/TE/TF (upper right image) were a form of BX carburettor with a cross-flange similar to Holdens. These would appear to orient the linkage and float correctly for the original grey motor manifold. 1 Page 80 of 148 10 Multiple Carburettors (Twins and Triples) Whilst twin and triple carburettors were never available from the factory for early Holden grey motors (the first twins being available on HD Holden 179ci X2 red motors long after the death of the grey motor), they remain a popular period-correct performance addition to many vehicles. Some enthusiasts believe that multiple carburettors offer an advantage where the fuel has less far to travel down the manifold (compared to a single, larger or two-barrel carburettor). This infers less fuel drop out and better supply. Spreading the fuel supply points (from one point to two or three along the manifold) can also assist in getting more even fuel distribution to the cylinders – the single Stromberg carburettor has a tendency to “overfeed” the centre cylinders at the expense of cylinders one and six. Alternatively, other enthusiasts believe that the multiple power valves associated with twin and triple Stromberg carburettors can supply too much fuel and do not open simultaneously, leading to erratic transition from cruise to power. The Holden grey motor is renowned for being “asthmatic”, with twin carburettors one way of making them breathe easier. Whilst it helps to be able to breathe in more, it is of little use if you can‟t breathe it out. The factory Holden grey motor exhaust manifold is just as restrictive as the inlet side, and is best modified (headers or extractors) to get the full benefit of multiple carburettors. 10.1 Carburettor Model and Manifold Choice Assuming that you have a manifold and are trying to decide on what carburettors to fit to it, the starting point will be to make two measurements – the bolt spacing, and the throttle bore diameter (see picture to the right). The bolt spacing, is measured between the studs (or bolt hole) centres on the 3 manifold. The bolt spacing for the BXOV-1 carburettor (2 /8”) is different from that of 11 the BXUV-2 and BXV-2 carburettors (2 /16”). Although you can sometimes drill and retap the manifolds to change the bolt spacing, it is a lot easier to choose the right carburettors to suit the manifold. The throttle bore diameter is measured across the “holes” in the manifold. If the carburettor and manifold throttle bore diameters do not match up, the resultant “step” in the fuel path can lead to either fuel drop-out or reduced flow. The throttle bore 5 diameter for the BXOV-1 and BXUV-2 carburettors (1 /16”) is different to that of the 7 5 7 BXV-2 carburettor (1 /16”). It is possible to mill out a 1 /16” manifold to 1 /16”, or to swap a BXOV-1/BXUV-2 throttle body onto a BXV-2 carburettor, it is again easier to choose the right carburettors to suit the manifold. Having made the two measurements, it is now time to think about what venturi size to pursue. Most enthusiasts find that for Holden grey motors, the Stromberg carburettor of choice in twin and triple 1 applications is the BXOV-1 or HD/HR/HK taxi BXUV-2 (both have 1 /32” diameter venturis and the same 3 throttle bore diameter, just different bolt spacing). Whilst it is possible to run the larger BXUV-2 (1 /32” 5 venturi) or BXV-2 (1 /32” venturi) carburettors in twin or triple configuration, there is no need to do so on the grey motor. The larger venturi diameter can lead to decreased mid-range acceleration – see notes below on venturi sleeves. The table below summarises the different bolt spacings, throttle bore diameters and venturi sizes available, together with the Code number stampings to look for on eBay and at swapmeets: Page 81 of 148 Vehicle Stamping Bolt Spacing Model Venturi Diameter Throttle bore diameter Holden EH 149ci engines, HD, HR, HK, HT, HG and LC 149ci and Holden HD 149ci 161ci and HR and HK engines, Holden 48-EJ 161ci economy some HD (taxi) engines. 179ci engines, HR and HK 186ci economy (taxi) engines and HR 186ci X2 engines. 23-3002, 233005, 23-3007, 23-3009, 233010 23-105D, 2323-3011 and 2323-3012, 233000 and 233022 3013, 23-3015, 3001 23-3016, 233019, 23-3021, 23-3023 and 23-3024 3 11 2 /8” 2 /16” BXOV-1 BXUV-2 1 3 1 /32” 1 /32” 5 1 /16” Holden EH and some HD 179ci engines, HD, HR (excluding taxi and X2), HK (excluding taxi), HT and HG 186ci engines 23-3003, 23-3008, 23-3006, 23-3014 and 23-3020 BXV-2 5 1 /32” 7 1 /16” Note that the venturi diameter is normally cast into the side of the main 1 body adjacent to the float needle valve seat ( /32” in the case of the BXOV-1 carburettor pictured in the image to the right). 10.2 Linkages Whilst there are a limited number of twin and triple carburettor throttle linkage kits available “off the shelf”, in the end most linkages are made from an assortment of parts sourced from your local speed shop. Speco Thomas manufacture a fair range of these components – see below. Part W-clips Speco Thomas Part No. 221139 (pack of 1) 221140 (pack of 2) Image Page 82 of 148 Ball joint assembly 221093.A Where „A‟ is the dimension shown in the image (2”-12” in 1” increments) Ball joint rod 221094 (available 2”-12”) 221097 (left-hand thread) 221098 (right-hand thread) 221108 ¼” 5 221106 /16” 221099 221150 (21” x /16”) 221174 (pack of two, suits /16” rod) 221102 (suits /16” rod) 5 5 5 Ball joint Ball joint ball Uniball Throttle rod Throttle rod stops Carburettor arm Accelerator cable clamp 221145 ( /16” swivel) 3 Accelerator cable stop 221146 ( /16” swivel) 3 Accelerator cable stop (holder) 221144 (¼” thread) 221159 (¼”x /16” 5 221156 (2”x /16”) 5 221158 (3¼”x /16”) 221163 (SU spring, swivel ends) 221166 (long) 5 Stud and nut kits Throttle springs There are a number of types of linkage setup, some of which are dependent on the manifold type. I will try to describe them using the Speco Thomas part names above in italic text for clarity. Page 83 of 148 The “W-clip” linkage – the aim of W-clip linkages is to use a throttle rod (common shaft) to join (marry) the original throttle shafts of the carburettors together. Both carburettors thus operate as one unit. One end of each W-clip slides over the original carburettor throttle shaft, whilst the other end clamps to the new throttle rod. Also clamped to the throttle rod is a carburettor arm. The carburettor arm needs to be moved to operate the carburettors – this is most often achieved by fitting an accelerator cable stop or accelerator cable clamp to the end of the carburettor arm and converting the vehicle to a cable accelerator setup (see Section 10.2 below). The carburettor arm has several sets of holes to allow different accelerator pedal travels to be accommodated. The pictures above show the Wclip linkage in both twin and triple carburettor format. Whilst fairly low cost, the W-clip linkage must be removed in order to get to the main jets, as the shaft is in the way. The shafts also develop a considerable amount of slop over time due to poor clamping of the W-clips and carburettor arms. In W-clip linkage setups, the choke plates on each of the carburettors should be linked (joined) together. It is poor practice to connect just one choke and leave the other one (or two) swinging in the breeze as they may swing closed. The chokes can be linked with a fixed length of steel or wire - you can even use a hacksaw blade and use the two choke cable screws. For vehicles which do not operate in a cold climate, the second (and third) choke plate may not be necessary, and the actuating lever can be wired into the open position. Note that the W-clips mount to the throttle shaft in two ways. On the rear carburettor, the pump lever nut is removed, and the W-clip is slid over the throttle shaft before replacing the nut. On the front carburettor, the W-clip similarly mounts under the throttle lever nut. However, on BXOV-1 carburettors, the throttle shaft does not have a nut on the throttle lever end – the throttle shaft is peined over instead. On the later BXUV-2 and BXV-2 carburettors the throttle shaft does have a nut on the throttle lever side. This means that W-clips cannot be used on the BXOV-1 carburettors unless the throttle shafts are replaced. There are also two types of W-clips being produced. The black W-clips seen beside the cadmium plated carburettor arm and throttle rods in the two images above have D-shaped holes at one end, which allow them to be slipped directly over the D-shaped profile of the Stromberg throttle shafts. The W-clips being Page 84 of 148 produced by Speco Thomas have round holes at both ends, and must be used with adaptors to fit to the Stromberg throttle shafts (see image to the right). The adaptors are threaded at one end to fit the throttle shafts, and round bar at the other end to fit the W-clips. Manifold-mounted linkage - some manifolds can run a manifoldmounted linkage. These linkages typically have a throttle rod mounted to the inlet manifold – some by bolt-on brackets (see image to the right, an off-the-shelf linkage stocked by American Autos as part number LINKIT) and some by using loop bosses cast into the manifold (see drawing below). Some also attach the throttle rod to the top of the carburettor air horns (see pictures of a Lanspeed manifold with red air cleaners in Section 10.8 below). Like the W-clip linkages, manifold-mounted linkages aim to operate the two (or three) carburettors equally. Two (or three) separate carburettor arms (one for each carburettor) are clamped to the throttle rod and connected to each carburettor throttle lever by ball joint assemblies. As the carburettors are not connected (married) together like the W-clip linkage, this type of linkage is often referred to as a divorced setup. The throttle rod is again fitted with a single carburettor arm which needs to be moved to operate the carburettors. Because the throttle rod is much longer than in W-clip linkages, there is more ability to move the carburettor arm closer to the firewall, allowing many manifold-mounted linkages to be connected by a ball joint assembly to the original throttle control adjusting bracket. In some cases, the original lever on the upper cross shaft assembly is extended by a piece of flat bar. The better type set-ups use hexagonal throttle rods to avoid the clamps slipping. The beauty of divorced-type linkages is that each carburettor may be adjusted as it has its own ball joint assembly. The image below shows a typical manifold-mounted linkage which uses loop bosses and the original throttle control adjusting bracket – note that I have shifted the carburettors to the left of the image and simplified the manifold outline for clarity. Page 85 of 148 Similarly to W-clip linkage setups, the choke plates on each of the carburettors should be linked (joined) together when using manifold-mounted linkages. Progressive linkage – progressive linkages are normally seen with triple (though sometimes twin) carburettors. Whilst this form of linkage also typically mounts to the manifold, the way in which the carburettors operate is different. The aim of the progressive linkage is to allow the vehicle to operate on a single carburettor at light loads (economy), with more carburettors being activated as the throttle opens more (power). Setups are often made such that the middle carburettor (in triple configurations) is the light-load carburettor, with the two outer carburettors coming on line under load. Off-the-shelf progressive linkages are widely available, for example from Speedway Motors (http://static.speedwaymotors.com/pdf/560-6271.pdf). However, most of these linkages assume the carburettors have aligned throttle shafts – Stromberg B-Model manifolds normally have the throttle shafts between the carburettors. Stromberg B-model progressive linkages usually use either a sliding eye or sliding rod type progressive ball joint connection (see image to the right). The carburettor used for light loads (labelled the economy carburettor) is normally driven by the original throttle control upper rod (which sometimes must be extended). This is indicated by the red arrow in the image above. The economy carburettor then drives the other two carburettors (labelled power carburettors above) via the progressive ball joint connection. The economy carburettor throttle arm can turn a significant amount before the sliding eye bottoms out (or Page 86 of 148 the sliding rod hits its stop) and the power carburettors start to be activated. A typical layout is shown below: Quite some thought is required to scratch-build a progressive linkage – for example, the economy carburettor has little shaft movement left when the power carburettors open – this small movement must be amplified into full throttle movement for the power carburettors by carefully selecting carburettor arm length and angle. In progressive linkage setups, it is common to connect the economy carburettor to the standard choke cable, and either wire the power carburettor choke levers fully open or remove the choke plates. This is because at the low throttle startup conditions, only the economy carburettor is working – the throttle plates on the power carburettors are fully shut. A triple Stromberg progressive linkage (see pictures of a Speco manifold with rectangular chromed air cleaners) is also shown in Section 10.8 below. Page 87 of 148 10.3 Accelerator Linkage to Cable Modification With some manifolds and linkages, it is possible to use the original throttle linkage (the swinging bar type) with a little bending. However, most manifolds and linkages will not allow their use no matter how much they are bent. It is often easier to convert the throttle linkage to a cable type, eliminating the complex linkage. A number of pedal/cable assemblies can be mounted into FB/EK Holdens, notably HZ Holden and Commodore. A neat (and simple) solution is to retain the original FB/EK pedal, and modify it to suit the cable from a Mitsubishi L300 Express van. These vehicles were sold from 1980-1986, and look similar to the photographs to the right. Note that the later models however do not have the required clevis at the cable end. The Mitsubishi L300 accelerator cable is quite long, and can be shortened with a simple pair of sidecutters to the correct length once installed. To undertake the conversion: 1. Remove all the throttle linkage except the pedal. Remove the clip connecting the lower cross shaft operating rod to the accelerator pedal (under the car), Unbolt the lower cross shaft assembly (four phillips-head bolts located under the car). Remove the clip connecting the upper cross shaft operating rod to the upper cross shaft assembly. All the linkage from under the car should now fall out Unbolt the upper cross shaft support (two phillips-head bolts per bracket, one bracket on drivers and passengers side of firewall. Disconnect the throttle control upper rod from the carburettor. All the linkage from in the engine bay should now fall out. Don‟t discard all the parts yet – the upper cross shaft support from the passenger‟s side makes a good bracket for supporting the cable later. 2. Attach the Mitsubishi L300 accelerator cable clevis to the original Holden accelerator pedal, using the hole that the lower cross shaft operating rod mounted to (under the car). The cable can be attached with a pin and split pin, or by using a small bolt and nylock nut (do not overtighten the nut as it will bind the clevis). Page 88 of 148 3. The cable will now run into the cabin using the Mitsubishi L300 cable guide. You will need to drill a hole in the floorpan for the cable to pass through, and another two for the cable guide mounting bolts. Mount the cable guide using nuts, bolts and spring washers, with some sealant under the cable guide to prevent water ingress to the cabin. The photographs above show the mounting of the clevis and cable guide on a number of vehicles. 4. Run the cable inside the cabin, up the firewall (under the carpet/floor mat) and pass it out through the grommet where the original choke cable passes through. The picture to the right shows the cable routing with the carpet/floor mat removed. 5. The cable then passes across the engine bay to the carburettor throttle linkage. The cable must be mounted, similar to the way that the choke tube holder assembly mounts the original choke cable (the photograph below to the right shows a holder assembly fitted to a Holley carburettor, and the photograph to the left to a twin Stromberg setup). 6. The cable setup often feels much lighter than the original throttle linkage, and an extra (or heavier) return spring can assist in returning the pedal feel. The photo below to the right shows a return spring mounted off a bracket on the original battery tray. 7. The cable assembly should be checked and adjusted so that the carburettor both achieves wide open throttle, and returns to idle. It‟s a good idea not to cut the cable to final length until this has been done. In some cases, it may be necessary to extend the accelerator pedal lever (by welding on a piece of flat bar) in order to get enough pedal travel to attain full throttle. 10.4 Fuel and Vacuum Lines When plumbing twin and triple Stromberg carburettors, the terms “fuel rail” and “fuel block” are bandied about, making the fuel lines sounds a lot more complex than they really are. A fuel rail is really a piece of pipe feeding fuel to both carburettors, and a fuel block is really a glorified tee-piece. Fuel lines should be run from the fuel pump to an area close to the carburettors in steel line, supported to stop it rubbing due to vibration. Brake repair shops are not a bad place to get some fuel lines bent and fittings flared on, though try to run the lines in the largest size you are able to. Closer to the carburettors you can continue to run in steel line (neater), or you can run in rubber fuel hose. It is a good idea to double-flare fuel lines where they meet rubber hoses, as the rounded flare “lump” can stop the hose clamps (jubilee clips) blowing off – care needs to be taken though that the ends of the steel lines are smooth and will not cut the rubber hose. I have also seen quite a few fuel systems run in copper pipe, however many engineers frown on the use of copper pipe in fuel systems (and absolutely forbid it in brake systems) because vibration can lead to the copper lines work-hardening and cracking – cracked fuel lines under pressure at Page 89 of 148 freeway speeds are no laughing matter. The photos below give some good guides as to how the fuel lines can be run. The original B-Model carburettors used on early Holdens had a vacuum connection (a steel line) that connected from the carburettor, snaked it‟s way around the rocker cover and connected to the distributor vacuum advance. This connection needs to be replicated in multiple carburettor setups. When thinking about this vacuum line, it is important to realize that there are two types of vacuum commonly tapped off a fuel system: • Manifold vacuum (sometimes referred to as full vacuum), which is used for brake boosters and vacuum wipers. It is tapped off from the inlet manifold, or on the carburettor throttle body at a position below the throttle plates. You get more manifold vacuum when you take your foot off the throttle (this is why pre-EK vacuum wipers work so well when you lift your foot, but run poorly when you have your boot into it driving uphill in the pouring rain!). • Timed-spark vacuum (sometimes referred to as distributor vacuum) is taken from above the throttle plates. Timed spark vacuum is exactly the same as manifold vacuum – except that it is shut off under zero throttle (i.e. under idle conditions, there is huge manifold vacuum, but zero distributor vacuum). The strategy behind distributor vacuum (generally used in later-model carburettors) is to remove vacuum advance at idle, causing the vehicle to run hotter and combust exhaust emissions (often with the help of air injection systems at the exhaust manifold). Early Holdens were designed to run timed spark vacuum (the vacuum port connection is at the throttle body above the throttle plate – see diagram to the right). There is no harm in running distributor vacuum with multiple carburettors (by tapping into one carburettor and blocking the other one off - tapping into both carburettors and using a tee-piece is absolutely unnecessary). However, for cars with large cams (high valve overlap and poor vacuum), tapping into manifold vacuum (and blocking off the distributor vacuum ports on both the carburettors) can give better vacuum signal at idle, more advance and hence better idling. This can also reduce engine temperature at idle. 10.5 Venturi Sleeves By adding a second (or third) carburettor, the “hole” to allow air into the engine has effectively doubled (tripled) in size. Whilst this is good for air flow, it can do some interesting things inside the carburettor, where pressure is critical. By doubling (or tripling) the “hole”, the pressure in the venturi has reduced. Of note: The idle system, which operates below the venturi, still sees the same pressure and acts similarly to a single carburettor (see tuning notes below). The main metering system takes vacuum signal from inside the booster venturi, which in turn takes signal from the main venturi. With lower pressure means that less fuel is taken per carburettor (though there are now two carburettors feeding). The slower air speed also means that the fuel delivered is not atomized as well as a single carburettor. The accelerator system sees no difference in having two (or three) carburettors, as it is purely mechanical and not vacuum driven (see tuning notes below). The power system sees no difference in having two (or three) carburettors, as it takes it‟s signal from the manifold pressure (just like the idle system). The choke system sees no difference in having two (or three) carburettors as it operates above the venturi. As can be seen from the above, running two (or three) carburettors can have an impact on the main metering system. This is often seen as good idle, then moderate initial acceleration (as the accelerator system works), then very sluggish acceleration while the main metering system gets the engine up to speed, followed by decent performance as the main system takes over. If the venturi diameter is reduced, the pressure issue goes away, and the sluggish performance is removed. Holden recognized this when it fitted twin carburettors to the HD and HR Holden red X-2 motors – the single BXV-2 carburettor with a 5 3 1 /32” venturi was replaced with twin BXUV-2 carburettors with smaller 1 /32” venturis. Unfortunately, for Page 90 of 148 the smaller capacity grey motors the BXOV-1 carburettor has no locally available smaller-venturi alternative to use when fitting twin and triple carburettors. One way however to improve the sluggish performance is to fit venturi sleeves (sometimes referred to as venturi restrictors), Venturi sleeves increase air speed through the venturi, getting the good vacuum signal back to the main metering system and helping fuel atomisation. This removes the sluggish low-down acceleration. Venturi sleeves were once anecdotally made by an FX/FJ enthusiast to fit the BXOV-1 carburettor, though enquiry to find the person has come up empty. Venturi sleeves however are available for the Holley 7448 carburettor (the legendary “Holley 350”). Redline Performance venturi sleeves are available from American Auto Parts (part number 14-35) and Barnes Performance (part number BP14-35). It must be recognized that the sleeves are made for a 3 1 venturi diameter of 1 /16” , and must be filed back (so they close up more) when fitting to the 1 /32” BXOV1 venturi. The filing appears to be extensive – almost ½”needs to be removed from the circumference. 1 The Redline Performance venturi sleeves are 0.035” thick (~ /32”), and if gapped correctly will change a 1 31 BXOV-1 venturi diameter from 1 /32” diameter to 0.96” diameter (~ /32”). Note also that in fitting venturi sleeves, the signal sent to the main metering system is much stronger (i.e. the main metering jet gets “sucked on” harder. This can lead to the main metering system running rich. When fitting venturi sleeves, the main metering jets will need to be decreased in size to account for this (see tuning notes below). 10.6 Synchronisation When synchronizing multiple carburettors, the aim is to make the carburettors draw in equal amounts of air (and hence fuel). If the carburettors are not synchonised, one carburettor can run richer than the other, leading to some of the cylinders running richer (or leaner) than others. Carburettors are normally synchronized at idle conditions. There are a number of ways of telling if a carburettor is synchonised. The cheapest (and often very effective) way is to listen to the carburettor. To use this method: Disconnect the linkage that connects one carburettor to the other. A piece of tube (often rubber fuel hose) is inserted into the open throat of one of the carburettors, just near the top and without blocking off the air flow. After listening to the “hiss” of the carburettor, the hose is moved to the second carburettor and the throttle plates of both carburettors are adjusted (via the slow idle adjusting screw for Stromberg carburettors) until the pitch and volume of the “hiss” is the same for both carburettors. This involves a bit of to-and-fro adjusting and backing off both throttle plates so that the “hiss” is the same from both carburettors at the same time that the idle speed is satisfactory. Blip the throttle to see that the carburettors come back to an equal “hiss” (worn throttle shafts can mean that the synchronisation may take a few goes). Once the “hiss” is equal and the resultant idle speed is OK, the idle mixture is set by adjusting both screws evenly (for Stromberg carburettors, this is the idle needle valve). After setting the idle mixture, the carburettors are again synchronized by listening to the “hiss”. Reconnect the carburettor linkage, and listen to the “hiss”. If one carburettor now draws more, adjust the carburettor linkage until it is back to roughly equal. Bring the engine speed up to approximately 1500rpm, and again listen for the “hiss”. If one carburettor is significantly different from the other, examine the carburettor linkage to identify the reason why. If the reason cannot be found, the idle setting on one carburettor may be increased and Page 91 of 148 the setting on the other decreased to allow the carburettors to be in balance under load. This is not a great practice, and it is far preferable to balance the linkages (for example by adding washers under some of the arms). An alternative method is to use a carburettor synchronisation tool such as the Holley Carburetor Synchronizer shown in the lefthand image, or the Edelbrock Uni-syn tool shown in the middle image. A genuine service tool as also made by Coxhead for GMH twin carburettor balancing – see righthand image. Synchronisation tools measure the flow of air and give a reading (normally by a float tube or dial). The process for synchronisation with a tool is the same as the above listening method, though instead of getting the same “hiss” from each carburettor, you are aiming to get the same float-tube reading. A further alternative is to use a manometer (essentially a 6‟ length of clear plastic tube ½ filled with water or kero). The two ends of the manometer tube are connected to the carburettor above the venturi. The vacuum in the carburettors sucks on both ends of the tube – if one carburettor has more vacuum, the water lifts up higher in that side. This works on some carburettors that have a spare vacuum tapping, like motorbikes. It‟s not applicable for most cars though as they do not have a vacuum tapping point. Although 1 it would be possible to use the /8” NPT port used to connect the vacuum advance line to the throttle body, the port is located very close to the throttle plates. Turbulence in this area would not provide a sufficiently accurate pressure measurement in order to use a manometer. 10.7 Tuning Once the carburettors are synchronized, they may be tuned. Generally, multiple carburettors are tuned by running the same size main metering jets and power bypass jets in all carburettors, then following the same principles as for tuning single carburettors. Some notes which may help: In multiple carburettor setups, it is possible that the idle system can overfeed the motor. Normally the idle screws allow enough adjustment that the idle can be leaned up enough even though there are two or three carburettors feeding. However, once the carburettors come off idle, the secondary idle system comes into play. The upper two idle discharge holes are not controlled by the idle mixture screw, but only by the size of the idle tube. The upper two idle discharge holes can thus overfeed the motor causing it to run rich under cruise conditions (i.e. the secondary idle system is doing some of the job of the main metering system). It is possible to down-size the main metering jets to compensate (easier), or to down-size the idle tubes to supply less fuel. Whilst all the grey motors had the smaller Nº. 70 drill (0.0280”) idle tube, some of the red motors had the larger Nº. 68 drill (0.0310”) idle tube. The table in Section 5 gives some guidance as to which vehicles to hunt down to find the smaller idle tubes. The WW Stromberg idle tube used in HR186S engines is of different design (see Page 92 of 148 image below to the right), and is not interchangeable with the earlier B-Model idle tubes (image to the left). Whilst the Stromberg 97 (EE-1) idle tube is interchangeable with the B-model idle tube, I understand that Stromberg Carburetor Ltd supply only the Nº. 70 idle tube for Stromberg 97s. It is easier to run fixed main metering jets rather than adjustable main metering jets. Even if the jets are “screwed out” the same as each other, it is a lot more difficult to ensure that they are “screwed out” the same. At the extreme, it can lead to one carburettor (and hence one or more cylinders) running rich whilst others run lean. Main metering jets will be a lot smaller than when running a single carburettor. 46, 47 or 48 jets on a standard to mild grey motor is a good starting point for twin or triple Stromberg carburettors (though will need to be tuned as all engines run differently). With two accelerator pumps running, the amount of fuel being delivered with each pump shot can be excessive (this may be seen by hesitation during acceleration, or by a puff of black smoke when initially accelerating). The accelerator pumps may need to be tuned as per the guidance in section 6.3 above. Tuning multiple power bypass valves can be a challenge, as differences in the vacuum power pistons (and manifold pressures at each carburettor) can see each of the power bypass valves opening at different times. Some enthusiasts solve this by deleting the valves (blocking them off) and running much richer primary metering jets. Whilst this may solve the issue at full throttle, it will lead to a very rich “cruise” condition and is not recommended for street use. Typically the power bypass jets will need to be reduced from Nº.67 drill to Nº.70 drill jets when running multiple carburettors. Note that whilst it appears that the HR Holden 186S (WW-Model) power bypass jet is interchangeable with the early B-Model power bypass jets, the HR Holden valve has two Nº.56 drill (0.0465”) holes (i.e. much larger capacity) than the B-model singlehole power bypass valves. Using multiple carburettors means that the flow to individual cylinders can be a lot better than a single carburettor set-up. In twin-carburettor set-ups, the front carburettor tends to feed the front three cylinders, whilst the rear carburettor feeds the back three cylinders. Generally, there is little variation in fuel fed to the front and back three cylinders in this case. Triple carburettor manifolds however tend to feed the front two cylinders from the front carburettor, cylinders three and four from the middle carburettor and the back two cylinders from the rear carburettor. In this case, differences in carburettors can lead to some cylinders being starved. Some enthusiasts have found that cylinders three and four get robbed (run lean) by the front and rear cylinder pairs (which run rich). This is the opposite of the single carburettor manifold, which tends to rob the outer cylinders. The issue is often fixed by running richer jets in the centre carburettor of triple carburettor manifolds. Ideally, the exhaust gas coming from the front, middle and rear cylinder pairs should be measured with an exhaust gas analyser and the jetting in each of the three carburettors tuned to suit. However, most exhaust manifolds do not have the ability to “tap in” to the cylinder pairs. It is possible to weld nuts onto the exhaust manifold runners, drill them out and use them as sample points (plugging them with a short bolt or screwed plug during normal operation). An easier (albeit less accurate) way to tune the carburettors is to measure the exhaust manifold temperature for the cylinder pairs using an infrared temperature gun. Cylinders which are running leaner have higher temperatures, cylinders which are running richer have lower temperatures. Jetting can then be changed to balance the temperatures. Page 93 of 148 10.8 Examples of Twin and Triple Setups (Stromberg Porn) The pictures below show some different ways of setting up linkages, fuel rails, choke and vacuum lines. I have presented the pictures in large format (at the expense of a few extra pages in this document) to help make it easier to see some of the linkages and fittings used (besides, no-one wants to be squinting at Stromberg porn). I apologise in advance for the number of pages here, though to be honest when you are putting together a linkage from scratch, every photo you can lay your hands on helps. Page 94 of 148 Page 95 of 148 Page 96 of 148 Page 97 of 148 Page 98 of 148 Page 99 of 148 Page 100 of 148 Page 101 of 148 Page 102 of 148 Page 103 of 148 Page 104 of 148 Page 105 of 148 Page 106 of 148 Page 107 of 148 Page 108 of 148 Page 109 of 148 Page 110 of 148 Page 111 of 148 Page 112 of 148 Page 113 of 148 Page 114 of 148 Page 115 of 148 Page 116 of 148 Page 117 of 148 Page 118 of 148 Page 119 of 148 Page 120 of 148 Page 121 of 148 Page 122 of 148 Page 123 of 148 Page 124 of 148 Page 125 of 148 Page 126 of 148 11 “The Joker” Carburettor Lock Whilst not a NASCO accessory, The Joker carburettor lock (see image to the right and advertising below) is a period correct accessory for early Holdens. The Joker was fitted between the carburettor and the insulating spacer, using extended studs. By closing the key lock on The Joker, a throttle plate closed, preventing fuel and air supply to the engine. The Joker also acted as a spacer, giving rise to the claims in the advertisement below of better atomisation and performance (despite the thick-edged throttle plate being a fairly considerable obstruction to air flow). Page 127 of 148 12 Holden Part Numbers The following part numbers have been taken from the Master Parts Catalogue (20 Years of Holden Production). The list shows the separate service parts provided by GMH. Air horn assembly 48, 50, FJ, FE, FC, FB, EK, EJ Air horn assembly EH, HD, HR (excluding S engine) Air horn assembly HR S engine Air horn attaching screw and lockwasher 48, 50, FJ, FE, FC, FB, EK, EJ Air horn attaching screw and lockwasher – long EH, HD, HR (excluding S engine) Air horn attaching screw and lockwasher – short EH, HD, HR (excluding S engine) Air horn attaching screw and lockwasher HR S engine Air horn gasket 48, 50, FJ, FE, FC, FB, EK, EJ, HD, HR (excluding S engine) Air horn gasket HR S engine Air horn reinforcing bar EH, HD, HR (excluding S engine) Carburettor actuating torsion lever HR S engine Carburettor assembly 48, 50, FJ Carburettor assembly FE, FC, FB, EK (manual), EJ (manual) Carburettor assembly EK (automatic), EJ (automatic) Carburettor assembly EH 149 engine, HD 149 engine, HR (automatic) 161 engine Carburettor assembly EH 179 engine, HD 179 (excluding X2) engine, HR (automatic) 186 (excluding X2 and S) engine Carburettor assembly HD 149 engine, HR 161 engine economy carburettors Carburettor assembly HD 179 (excluding X2), HR 186 (excluding X2 and S) engine economy carburettors Carburettor assembly HR (manual) 161 engine Carburettor assembly HR (manual) 186 (excluding X2 and S) engine Carburettor assembly - front HD X2 engine, HR (automatic) X2 engine Carburettor assembly – rear HD X2 engine, HR (automatic) X2 engine Carburettor assembly – front HR (manual) X2 engine Carburettor assembly – rear HR (manual) X2 engine Carburettor assembly HR (manual) S engine Carburettor assembly HR (automatic) S engine Choke kick diaphragm HR S engine Choke kick diaphragm attaching screw HR S engine Choke kick rod assembly HR S engine Choke kick rod retainer HR S engine Choke kick rod vacuum hose HR S engine Choke lever assembly 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Choke lever spring 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Choke shaft and lever assembly 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Choke shaft and lever assembly HR S engine Choke rod HR S engine Choke rod cotter pin HR S engine Choke shaft bushing 48, 50, FJ, FE, FC, FB, EK, EJ 7405154 7424552 VS10461 7405166 7405167 7405166 7405166 7405148 VS10462 7420240 7428170 7402765 7412264 7418661 7426784 7426904 7430100 7430107 7431861 7431862 7428498 7428502 7432512 7432513 7432636 7432635 VS10455 VS10531 VS10456 VS10457 VS10458 7405122 7405125 7405117 VS10459 VS10444 VS10454 7405113 Page 128 of 148 Choke tube holder assembly 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Choke tube holder attaching screw and lockwasher 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Choke tube clamp screw 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Choke tube clamp screw nut 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Choke tube clamp screw washer 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Choke wire clamp screw 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Choke wire connector 48, 50, FJ, FE, FC, FB, EK, EJ Choke valve assembly 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Choke valve assembly HR S engine Choke valve attaching screw 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Choke valve attaching screw HR S engine Dashpot HR S engine Dashpot bracket HR S engine 5 Dashpot nut hexagonal jam /16”-24 HR S engine Dashpot screw and lock washer HR S engine Fast idle cam 48, 50, FJ, FE, FC, FB, EK, EJ Fast idle cam EH, HD, HR (excluding S) engines Fast idle cam lever 48, 50, FJ, FE, FC, FB, EK, EJ Fast idle cam lever EH, HD, HR (excluding S) engines Fast idle cam pin 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Fast idle cam lever cotter pin (extension prong) 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Fast idle lever 48, 50, FJ, FE, FC, FB, EK, EJ Fast idle lever EH, HD, HR (excluding S) engines Fast idle lever attaching nut 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR Fast idle lever attaching nut washer 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) o Fast idle lever attaching nut washer – spring lock N . 10 HR S engine Fast idle rod 48, 50, FJ, FE, FC, FB, EK, EJ Fast idle rod EH, HD, HR (excluding S) engines Fast idle rod HR S engine Fast idle rod cotter pin 48, 50, FJ, FE, FC, FB, EK, EJ Fast idle rod cotter pin EH, HD, HR (excluding S) engines Fast idle rod retainer HR S engine Fast idle screw HR S engine Float chamber baffle HR S engine Float and lever assembly 48, 50, FJ, FE, FC, FB, EK, EJ, HD, HR (excluding S engine) Float and lever assembly HR S engine Float level gauge HR S engine 7405247 7405167 7405127 7405128 7405121 7405124 7405123 7405116 VS10460 7405118 7405165 VS10451 VS10450 124920 7405167 7405250 VS10248 7405249 7424560 7405111 7405140 7405119 7424548 7405120 7405121 131183 7405161 7424553 VS10472 7405140 7405140 VS10471 VS10521 VS10446 7405112 VS10445 VS10582 Page 129 of 148 Float fulcrum pin 48, 50, FJ, FE, FC, FB, EK, EJ, HD, HR 7405156 Float fulcrum pin spring 48, 50, FJ, FE, FC, FB, EK, EJ, HD, HR 7405170 Float needle valve and seat assembly 48, 50, FJ 7405155 Float needle valve and seat assembly FE, FC, FB, EK, EJ, EH, HD, HR (excluding S engine) 7406701 Float needle valve and seat assembly – heavy duty FE, FC, FB, EK, EJ, EH, HD, HR (excluding S engine) 7420335 Float needle valve and seat assembly HR S engine VS10443 Float needle valve and seat gasket 48, 50, FJ, FE, FC, FB, EK, EJ, HD, HR 7405147 Gasket - flange HR S engine 7433691 Gasket – flange 48, 50, FJ, FE, FC, FB, EK, EJ 7405279 Gasket – flange EH 149 engine, HD 149 engine, HD X2 engine, HR 161 engine, HR X2 engine 7424566 Gasket – flange EH 179 engine, HD 179 (excluding X2) engine, HR 186 (excluding X2 and S) engine 7424567 Gasket – flange HD 179 (excluding X2), HR 186 (excluding X2 and S) engines economy carburettors 7424566 Gasket – heat insulating EH 149 engine, HD 149 engine, HD X2 engine, HR X2 engine 7420678 Gasket – heat insulating EH 179 engine, HD 179 (excluding X2) engine 7420679 Gasket – heat insulating HD 179 (excluding X2 and S) engine economy carburettor7420678 Gasket kit 48, 50, FJ, FE, FC, FB, EK, EJ 7405179 Gasket kit EH 149 engine, HD 149 engine, HD X2 engine, HR 161 engine, HR X2 engine 7424290 Gasket kit EH 179 engine, HD 179 excluding X2 engine, HR 186 excluding X2 and S engines 7424535 Gasket kit HR S engine 7438608 Gasket kit HD 179 excluding X2, HR 186 (excluding X2 and S) Engines economy carburettors 7424290 High speed bleeder 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR 7405109 o Idle air bleeder (N 52) 48, 50, FJ, FE, FC, FB, EK, EJ, EH 149, HD X2, HR X2 engines 7405108 o Idle air bleeder (N 53) EH 149, HD 149, HR 161 engines VS10075 Idle air bleeder EH 179, HD 179 (excluding X2), HR 186 (excluding X2 and S) engines 7420491 o Idle air bleeder (N 52) HD 149, HR 161 engines economy carburettors 7405108 Idle air bleeder channel plug 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) 7405110 Idle needle valve 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR 7405174 Idle needle valve spring 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) 7405171 Idle needle valve spring HR S engine VS10438 o Idle tube (N 70) 48, 50, FJ, FE, FC, FB, EK, EJ, EH 7405135 o Idle tube (N 68) EH, HD, HR (excluding S) engines VS10074 Idle tube HR S engine VS10470 Idle tube conversion package EH 149 engine 7429177 Idle tube conversion package EH 179 engine 7429178 Idle vent valve EH, HD, HR (excluding S engine) 7420242 Idle vent valve stem EH, HD, HR (excluding S engine) 7420243 Page 130 of 148 Idle vent valve stem spring Idle vent valve washer Insulator Assembly – heat Insulator Assembly – heat Insulating spacer EH, HD, HR (excluding S engine) HR S engine 48, 50, FJ up to engine No. 283372 FJ from engine No. U283384, FE, FC, FB, EK, EJ 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Lead ball plug 48, 50, FJ, FE, FC, FB, EK, EJ, HD, HR Main body assembly 48, 50, FK, FE, FC, FB, EK, EJ Main body assembly EH 149 engine (piston part No. 7406080 Group 3.788 must be used with these bodies) Main body assembly EH 149, HD 149 HD X2, HR 161, HR X2 engines (piston part No. 7420249 Group 3.788 must be used with these bodies) Main body assembly EH 179 engine (piston part No. 7406080 Group 3.788 must be used with these bodies) Main body assembly EH 179, HD 179 (excluding X2), HR 186 (excluding X2 and S) engines (piston part No. 7420249 Group 3.788 must be used with these bodies) Main body assembly HD 149, HR 161 engines economy carburettors Main body assembly HD 179 (excluding X2), HR 186 (excluding X2 and S) engines economy carburettors Main body assembly HR S engine Main body attaching screw and lockwasher 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Main body attaching screw and lockwasher HR S engine Main body attaching screw and lockwasher HR S engine Main body channel plug 48, 50, FJ, FE, FC, FB, EK, EJ, HD, HR (excluding S engine) Main body channel plug HR S engine Main body gasket 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Main body gasket HR S engine Main discharge jet 48, 50, FJ, FE, FC, FB, EK, EJ Main discharge jet (28-30) EH, HD, HR (excluding S) engines Main discharge jet HR S engine Main metering jet (0.050”) 48, 50, FJ Main metering jet (0.051”) 48, 50, FJ, FE, FC, FB, EK, EJ Main metering jet (0.055”) EH 149, HD 149, HD X2, HR 161, HR X2 engines Main metering jet (0.053”) EH 149, HR 161 engines (high altitude 4000-8000 ft) Main metering jet (0.051”) EH 149, HR 161 engines (high altitude 8000-12000 ft) Main metering jet (0.059”) EH 179, HD 179 (excluding X2) engines Main metering jet (0.058”) EH 179, HD 179 (excluding X2), HR 186 (excluding X2 and S) engines Main metering jet (0.057”) EH 179 engine (high altitude 4000-8000 ft) Main metering jet (0.055”) EH 179 engine (high altitude 8000-12000 ft) Main metering jet (0.051”) HD 149, HR 161 engines economy carburettors Main metering jet (0.055”) HD 179 (excluding X2), HR 186 (excluding X2 and S) Engines economy carburettors Main metering jet (0.053”) HR S engine 7420244 VS10530 7400134 7409234 7405168 7405107 7405175 7424557 7420245 7424558 7420246 VS10188 7420245 VS10452 7405163 VS10523 7405167 7405158 VS10526 7405143 VS10433 7400370 740037 VS10532 7403431 7405264 7420388 7420385 7405264 7420412 VS10185 7424569 7420388 7405264 7420388 VS10533 Page 131 of 148 Main metering jet (0.051”) Main metering jet (0.049”) Main metering jet plug gasket 5 Nut, thick hex /16”-24 3 Nut – hex. /8”–24 – light (thick) HR S engine (high altitude 4000-8000 ft) VS10534 HR S engine (high altitude 8000-12,000 ft) VS10535 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR 7405144 48, 50, FJ, FE, FC, FB, EK, EJ 143416 EH, HD (excluding X2 engine), HR (excluding X2 and S engines) 120369 5 Nut – hex. /16”-24 – light HR S engine 120368 3 Nut – hex. /8”-24 HD X2 engine, HR X2 engine SP1656 1 Plug – auto hex. head pipe /8” NPTF HD X2 engine, HR X2 engine 444612 Power bypass jet assembly 48, 50, FJ, FE, FC, FB, EK, EJ 7406899 Power bypass jet assembly (No. 57) EH 149 engine 7424564 Power bypass jet assembly (No. 56) EH 149 engine, HD 149 engine, HD X2 engine, HR161 engine, HR X2 engine 7420490 Power bypass jet assembly (No. 55) EH 179 engine, HD 179 (excluding X2) engine, HR 186 (excluding X2 and S) engine 7420747 Power bypass jet assembly (No. 54) EH 179 engine 7424565 Power bypass jet assembly (No. 65) HD 149, HR 161 engines economy carburettors 7406899 Power bypass jet assembly (No. 56) HD 179 (excluding X2), HR 186 (excluding X2 and S) Engines economy carburettors 7420490 Power bypass jet assembly HR S engine VS10469 Pump check ball – inlet HR S engine VS10527 Pump check ball – outlet HR S engine VS10519 Pump and power bypass jet gasket 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR 7405146 Pump bypass jet assembly (No. 56) 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding S engine) 7405131 Pump check ball – inlet HR S engine VS10527 Pump check ball – outlet HR S engine VS10519 Pump check valve assembly with ball 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) 7405136 Pump check valve plug 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) 7405159 Pump check valve plug gasket 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) 7405145 Pump gasket HR S engine VS10468 Pump lever 48, 50, FJ, FE, FC, FB, EK, EJ 7405151 Pump lever EH, HD, HR (excluding S) engines 7424551 Pump lever HR S engine VS10464 Pump lever attaching nut 48, 50, FJ, FE, FC, FB, EK, EJ 7405128 Pump lever attaching nut EH, HD, HR (excluding S) engines 7424617 Pump lever attaching washer 48, 50, FJ, FE, FC, FB, EK, EJ 7405121 Pump lever attaching washer EH, HD, HR (excluding S) engines 7424168 Pump lever attaching screw HR S engine VS10517 Pump nozzle HR S engine VS10467 Pump nozzle screw HR S engine VS10518 Pump piston and stem assembly 48, 50, FJ, FE, FC, FB, EK, EJ, HD, HR (excluding S engine) 7405133 Pump piston and stem reducer 48, 50, FJ, FE, FC, FB, EK, EJ 7405106 Pump piston assembly HR S engine VS10449 Pump rod 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR Page 132 of 148 (excluding HR S engine) HR S engine 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Pump rod link spring clip 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Pump rod link repair kit 48, 50, FJ, FE, FC, FB, EK, EJ Pump rod link repair kit EH, HD, HR (excluding S) engines Pump rod link cotter pin HR S engine Pump stem cotter pin HR S engine Pump stem spring 48, 50, FJ, FE, FC, FB, EK (manual), EJ (manual) Pump stem spring EK (automatic), EJ (automatic) Pump stem spring EH, HD, HR (excluding S engine) Pump stem duration spring HR S engine Pump stem duration spring washer retainer HR S engine Pump stem duration spring washer clip HR s engine Pump stem bottom spring HR S engine Pump stem cotter pin 48, 50, FJ, FE, FC, FB, EK, EJ, HD, HR (excluding S engine) Pump strainer screen 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Pump strainer screen clip 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Repair kit – rebuild FE, FC, FB, EK (manual), EJ (manual) Repair kit – rebuild EK (automatic), EJ (automatic) Repair kit – major overhaul 48, 50, FJ Repair kit – major overhaul FE, FC, FB, EK, EJ Repair kit – major overhaul EH 149 engine, HD 149 engine, HR 161 engine Repair kit – major overhaul EH 179 engine Repair kit – major overhaul HD 179 (excluding X2) engine, HR 186 (excluding X2 and S) engine Repair kit – major overhaul HD 149, HR 161 engines economy carburettors Repair kit – major overhaul HD 179 (excluding X2), HR 186 (excluding X2 and S) engines economy carburettors Repair kit HR S engine Repair kit – major overhaul HC X2 engine Repair kit – minor overhaul 48, 50, FJ Repair kit – minor overhaul FE, FC, FB, EK, EJ Repair kit – minor overhaul EH 149 engine, HD 149 engine, HR 161 engine Repair kit – minor overhaul EH 179 engine, HD 179 (excluding X2) engine, HR 186 (excluding X2 and S) engine Repair kit – minor overhaul HD 179 (excluding X2), HR 186 (excluding X2 and S) Engines economy carburettors Repair kit – minor overhaul HD X2 engine, HR X2 engine Slow idle adjusting screw 48, 50, FJ, FE, FC, FB, EK, EJ, EH 149, HD 149, HD X2, HR 161, HR X2 engines Slow idle adjusting screw EH 179, HD 179 (excluding X2), HR 186 (excluding X2 and S) engines Slow idle adjusting screw HD 179 (excluding X2), HR 186 (excluding X2 and S) Pump rod Pump rod link 7405160 VS10465 7405153 7405138 7427342 7427343 7405140 7405140 7405169 7425236 7424555 VS10448 VS10528 VS10529 VS10447 7405141 7405162 7405139 7424283 7424284 7405285 7406879 7430071 7424577 7430399 VS10187 7430071 7438609 VS10146 7425197 7425198 7424574 7424575 7424574 VS10148 7405164 7424554 Page 133 of 148 Engines economy carburettors Slow idle adjusting screw HR S engine Slow idle adjusting screw spring 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) Slow idle adjusting screw spring HR S engine Thermostat cover assembly HR S engine Thermostat cover screw HR S engine Thermostat cover screw washer HR S engine Thermostat cover gasket HR S engine Thermostat lever and shaft assembly HR S engine Thermostat lever HR S engine o Thermostat lever and shaft assembly washer Spring lock N 6 HR S engine Thermostat lever attaching nut HR S engine Throttle body assembly 48, 50, FJ, FE, FC, FB, EK, EJ Throttle body assembly EH 149 engine, HD 149 engine, HR 161 (automatic) engine Throttle body assembly EH 179 engine, HD 179 (excluding X2) engine, HR 186 (automatic, excluding X2 and S) engine Throttle body assembly HR 161 (manual) engine Throttle body assembly HR 186 (manual, excluding X2 and S) engine Throttle body assembly HD 179 (excluding X2), HR 161, HR 186 (excluding X2 and S) engines economy carburettor Throttle body assembly – front carburettor HD X2 engine, HR (automatic) X2 engine Throttle body assembly – rear carburettor HD X2 engine, HR (automatic) X2 engine Throttle body assembly – front carburettor HR (manual) X2 engine Throttle body assembly – rear carburettor HR (manual) X2 engine VS10313 Throttle body assembly HR (manual) S engine Throttle body assembly HR (automatic) S engine Throttle body channel plug 48, 50, FJ, FE, FC, FB, EK, EJ, HD, HR (excluding X2 engine) Throttle lever and shaft 48, 50, FJ, FE, FC, FB, EK, EJ Throttle lever and shaft – 0.005” oversize 48, 50, FJ, FE, FC, FB, EK, EJ Throttle lever EH Throttle shaft EH Throttle shaft – 0.005” oversize EH Throttle lever HD (excluding X2) engine, HR (excluding X2 and S) engine Throttle shaft HD (excluding X2) engine, HR (excluding X2 and S) engine Throttle shaft – 0.005” oversize HD (excluding X2) engine, HR (excluding X2 and S) engine Throttle nut EH, HD (excluding X2) engines, HR (excluding X2 and S) engines Throttle valve 48, 50, FJ, FE, FC, FB, EK, EJ, EH 149 engine, HD 149 engine, HD X2 engine, HR 161 engine, HR X2 engine Throttle valve EH 179 engine, HD 179 (excluding X2) engine, HR 186 (excluding X2 and S) engine 7405164 VS10520 7405172 VS10474 VS10442 VS10525 VS10524 VS10441 VS10440 VS10439 131044 7420254 7405253 7428167 7428168 VS10309 VS10310 7428167 VS10149 VS10150 VS10312 VS10473 VS10453 7405158 7405248 7425403 7424559 7424619 VS10250 7424559 7428169 VS10251 7424617 7405173 7424556 Page 134 of 148 Throttle valve HD 179 (excluding X2), HR 186 (excluding X2 and S) Engines economy carburettors 7405173 Throttle valve HR S engine VS10437 Throttle valve attaching screw 48, 50, FJ, FE, FC, FB, EK, EJ, EH, HD, HR (excluding HR S engine) 7405165 Throttle valve attaching screw HR S engine VS10522 Throttle washer EH, HD (excluding X2) engines, HR (excluding X2 and S) engines 7424618 Throttle lever and shaft assembly – front carburettor HD X engine, HR X2 engine VS10151 Shaft and pump lever assembly – rear carburettor HD X2 engine, HR X2 engine VS10152 Throttle lever – rear carburettor HD X2 engine, HR X2 engine VS10153 Throttle lever and shaft HR S engine VS10436 Vacuum power piston assembly 48, 50, FJ, FE, FC, FB, EK, EJ, EH (on EH series must o be used with carburettor assembly part N s 7421339, o 7422385 and body assembly N s 7424557 and 7424558) 7406080 o Vacuum power piston assembly EH (must be used with carburettor assembly part N s 7406452, 7406453 and body assembly 7420245 and 7420246) 7420249 Vacuum power piston assembly HD, HR (excluding S) engines 7420249 Vacuum power piston assembly HD, HR (excluding S) engines economy carburettors VS10189 Vacuum power piston assembly HR S engine VS10466 Vent tube 48, 50, FJ, FE, FC, FB, EK, EJ 7405114 Vent tube EH, HD, HR (excluding S engine) 7424550 Volume restrictor rod EH, HD, HR (excluding S) engines 7420258 Volume restrictor rod HR S engine M35948 Page 135 of 148 13 Bendix Stromberg Part Numbers The following part numbers have been taken from The Bendix Corporation Australia (Automotive) Pty Ltd Carburettor and Fuel Pump Service Parts Catalogue No. PC2 issued March 1968. The list shows the separate service parts provided by Stromberg, and should be read in conjunction with the following notes: NOTE 1: A heavy duty viton needle and seating, part No. 2376199 is available for this carburettor. NOTE 2: These screws also secure the air horn reinforcing bar. NOTE 3: Supply also (1) 2376083 vacuum power piston. NOTE 4: P21778/68 fitted from August 1964. Use major repair kit RK665 for this later setting. NOTE 5: Used as throttle stop lever on these models. Throttle lever is 2376081. NOTE 6: For high altitude operation use P19442/053 for 4,000-8,000ft; P19442/051 for 8,000-12,000ft. NOTE 7: For high altitude operation use P19442/057 for 4,000-8,000ft; P19442/055 for 8,000-12,000ft. NOTE 8: Used on carburettors stamped 23-201, 23-201A, 23-202, 23-202A. Not required on carburettors stamped 23-201B, 23-202B. NOTE 9: For high altitude operation use 386208-051 for 4,000-8,00ft; 386208-049 for 8,000-12,000ft. NOTE 10: P19442-058 and P21778-68 fitted from August 1964. Use repair kit RK666 for this later setting. Numbering is as per the Stromberg diagrams below (note these are different numberings to the Holden diagrams given above): Page 136 of 148 BXOV-1, BUV-2 and BXV-2 Models Page 137 of 148 WW Models Page 138 of 148 Vehicle Part No Holden 48, 50, FJ, FE, FE and early FC (19481959). Holden FC (late), FB, EK and EJ manual transmissions (1959 - 1963). Holden EK and EJ automatic transmissions (1961 - 1963). Holden EH 149ci engines (August 1963 - early 1964). Holden EH 149ci engines with manual and automatic transmissions (early 1964 February 1965). Holden EH 179ci engines with manual and automatic transmissions (August 1963 – early 1964). Holden EH 179ci engines with manual and automatic transmissions (early 1964 – February 1965). Holden HD 149ci economy (taxi) engines (late 1965 – April 1966) and Holden HR, HK 161ci economy (taxi) engines (April 1966 – 1968). Holden HD 179ci economy (taxi) engines (late 1965 – April 1966) and Holden HR and HK 186ci economy (taxi) engines (April 1966 – 1968). Stamping Model Specification 23-105D 380228 RK654 PRK654 RBP1 23-3000 BXOV-1 2375000 23-3001 2375002 23-3002 BXUV-2 2375003 RK658 PRK658 ST5 23-3005 2375007 RK658 13/32” 385178 23-3003 BXV-2 2375005 RK659 PRK659 ST6 15/32” P19442-059 23-3006 2375008 47 48 82 85 89 78 9 18 19 20 21 22 23 24 25 26 27 29 29A 30 31 Major repair kit Minor repair kit Gasket set Rebuild pack Choke tube (cast in) Main discharge jet Main jet High speed bleeder Power jet Slow-running jet Needle and seating Needle and seating washer Lead ball (5 off) Vent tube Choke valve Choke valve screw (2 off) Choke lever and shaft Fast idle lever Fast idle lever nut lockwasher Fast idle lever nut Air horn attaching screw and lockwasher (5 off) Air horn Air horn gasket Fast idle rod Fast idle rod cotter pin Pump stem cotter pin Pump rod RK654A PRK654A ST1 RBP2 11/32” P19442-051 RBP3 23-3011 and 23-3012 and 23-3022 23-3021 BXUV-2 2375017 2375018 RK667 RK665 PRK658 ST5 11/32” 13/32” P19442-055 P19442-055 P23985-70 P19442059NOTE 10 P19442-051 382880-67 382880-65 P21778-70 382880-56 P2177870NOTE 4 2376000 P10666 P18772 NOTE 1 382880-55 382880-65 P21778-70 382880-56 385053 P24045 P24046 P22573 2376088 P24052 901004-K6 P16571 909521-K36 P24709 P24624 P24060 901207-K36(1) P21338 385078 909521-K36 (5) 386171 2376020 909521-K36 (3), 909522-K36 (2)NOTE 2 2376037 2376056 901207-K36(2) Page 139 of 148 32 33 34 36 37 38 39 40 41 42 43 44 45 46 49 50 52 53 56 58 59 62 63 65 66 67 68 69 71 72 73 74 75 76 80 Pump duration spring Pump piston Fast idle cam lever cotter pin Pump bypass valve Pump bypass valve gasket Pump screen clip Pump screen Float fulcrum pin spring Float and lever Float lever fulcrum pin Main body Pump inlet check valve Check valve plug gasket Check valve plug Main jet plug gasket Main jet plug Pump link clip Pump link Pump lever Pump lever nut lockwasher Pump lever nut Throttle valve Throttle body Idle needle valve Idle needle valve spring Fast idle cam pin Fast idle cam lever Fast idle cam Slow idle adjustment screw Slow idle adjustment screw spring Throttle lever Throttle valve screw (2 off) Main body and insulating spacer gasket (2 0ff) Main body insulating spacer Main body screw and lockwasher (2 off) P24287 2376017 385046 901207-K36 P24062/2x56 P19448 P23271 P23270 P23273 382537 P23272 385051 2376082NOTE 3 2376082 P18144 383080 P24678 383079 P23902 384391 384390 P21774 P24102 2376087NOTE 3 2376087 2376210 2376082 2376053 901006-K6 385050 901624-K36 2376062 2376063 P15478 P15481 P23620 385050 2376281 901004-K6 901834-K36 385173 2376036 385172 385048 P15456 P15831 Part of item 86 P20904 P24037 384677 909551-K1 2376051 2376055 2376054 2376174 P15456 #2376051 Page 140 of 148 81 83 86 87 88 90 94 95 96 97 94-97 98 99 100 101 102 103 104 105 - Drive plug Power jet gasket Throttle shaft Throttle lever nut lockwasher Throttle lever nut Vacuum power piston Choke tube clamp screw Choke tube holder Choke tube clamp screw lockwasher Choke tube clamp screw nut Choke tube holder assembled complete with screw Tube holder attaching screw and lockwasher Manual choke lever spring Manual choke lever Wire clamp screw Valve stem locknut Idle vent valve Idle vent valve stem Idle vent valve spring Flange gasket Air horn reinforcing bar Volume restrictor rod P15459 (2) 385176 387211 P15459 (3) P19448 2376052 P15459 (2) P15459 (3) 2376103 901066-K6 901624-K36 2376083 904231-K36 385175 901004-K6 901834-K36 385174 909522-K36 P24080 P24081 P12867 901818-K36 2376078 387211 2376083 2376188 Not used 2376079 2376080 P15022 2376066 2376064 2376075 2376066 - 2376039 Part No Vehicle Holden HD (February 1965 April 1966), HR and HK (April 1966 – 1968) automatic transmissions, HT, HG and LC 149ci and 161ci engines. Holden HD 179ci engines (February 1965 – April 1966). Holden HD (February 1965 – April 1966), HR and HK (April 1966 – 1968), HT and HG 186ci engines with automatic transmissions. Holden HD (February 1965 – April 1966) 179ci engines, Holden HD 179ci X2 engines front carburettor (February 1965 – April 1966) and HR (April 1966 – 1967) X2 Holden HD (February 1965 – April 1966) 179ci, Holden HD 179ci X2 engines rear carburettor (February 1965 – April 1966) and HR (April 1966 – 1967) X2 engines with automatic transmissions Holden HR and HK (April 19661968), HT, HG and LC 161ci engines with manual transmissions. Holden HR and HK (April 1966 – 1968), HT and HG 186ci engines with manual transmissions. HR 186ci X2 engines with manual transmission front carburettor (April 1966 – 1967). HR 186ci X2 engines with manual transmission rear carburettor (April 1966 – 1967) Page 141 of 148 engines with automatic transmissions front carburettor Stamping Model Specification rear carburettor. 47 48 82 85 89 78 9 18 19 20 21 22 23 24 25 26 27 29 29A 30 31 32 33 34 36 Major repair kit Minor repair kit Gasket set Choke tube (cast in) Main discharge jet Main jet High speed bleeder Power jet Slow-running jet Needle and seating Needle and seating washer Lead ball (5 off) Vent tube Choke valve Choke valve screw (2 off) Choke lever and shaft Fast idle lever Fast idle lever nut lockwasher Fast idle lever nut Air horn attaching screw and lockwasher (5 off) Air horn Air horn gasket Fast idle rod Fast idle rod cotter pin Pump stem cotter pin Pump rod Pump duration spring Pump piston Fast idle cam lever cotter pin Pump bypass 23-3013 and 23-3007 BXUV-2 2375009 RK665 PRK658 ST5 13/32” 23-3008 and 23-3014 BXV-2 2375010 RK666 PRK659 ST6 15/32” 23-3009 and 23-3015 23-3010 and 23-3016 BXUV-2 2375013 2375014 RK663 RK664 PRK663 ST5 13/32” 23-3019 2375024 RK665 PRK658 23-3020 BXV-2 2375025 RK666 PRK659 ST6 15/32” 23-3024 BXUV-2 2375027 RK663 PRK663 ST5 13/32” 23-3023 BXUV-2 2375028 RK664 385178 P19442-055 P19442-058 P19442-055 P19442/055NOTE 6 P19442/058NOTE 7 P19442/055 P23985-70 382880-56 382880-55 P21778-68 382880-56 P21778-70 2376000NOTE 1 P10666 P18772 386171 P24046 P22573 2376088 2376020 901004-K6 P16571 909521-K36 (3) 909522-K36 (2)NOTE 2 909521-K36 (4) 909522K36 (2)NOTE 2 909521-K36 (3) 909522-K36 (2)NOTE 2 2376037 P24624 2376056 901207-K36 (2) P21338 385078 P24102 385046 901207-K36 P24062/2x56 909521-K36 (4) 909522-K36 (2)NOTE 2 909521-K36 (3) 909522K36 (2)NOTE 2 P18772 (6) P18772 (5) 382880-55 P21778/68 382880-56 P21778/70 Page 142 of 148 37 38 39 40 41 42 43 44 45 46 49 50 52 53 56 58 59 62 63 65 66 67 68 69 71 72 73 74 75 76 80 81 83 valve Pump bypass valve gasket Pump screen clip Pump screen Float fulcrum pin spring Float and lever Float lever fulcrum pin Main body Pump inlet check valve Check valve plug gasket Check valve plug Main jet plug gasket Main jet plug Pump link clip Pump link Pump lever Pump lever nut lockwasher Pump lever nut Throttle valve Throttle body Idle needle valve Idle needle valve spring Fast idle cam pin Fast idle cam lever Fast idle cam Slow idle adjustment screw Slow idle adjustment screw spring Throttle lever Throttle valve screw (2 off) Main body and insulating spacer gasket (2 0ff) Main body insulating spacer Main body screw and lockwasher (2 off) Drive plug Power jet gasket P19448 P23271 P23270 P23273 382537 P23272 2376082 2376087 2376082 P18144 383080 P24678 383079 P23902 384391 384390 2376053 901006-K6 385050 2376104 901624-K36 2376062 2376105 Part of item 86 2376184 2376183 2376281 P15478 P15481 P23620 2376055 2376054 P15456 2376174 P15456 P15831 2376051NOTE 5 Part of item 86 2376168 P20904 P24037 384677 909551-K1 P15459 (3) P15459 (2) P15459 (3) P15459 (2) P19448 P15459 (1) P15459 (3) 2376051 Part of item 86 2376168 903925-K1 P15456 2376053 901006-K6 901624-K36 385050 2376284 2376293 Part of item 86 2376087 2376082 2376294 Page 143 of 148 86 87 88 90 94 95 96 97 9497 98 99 100 101 102 103 104 105 - Throttle shaft Throttle lever nut lockwasher Throttle lever nut Vacuum power piston Choke tube clamp screw Choke tube holder Choke tube clamp screw lockwasher Choke tube clamp screw nut Choke tube holder assembled complete with screw Tube holder attaching screw and lockwasher Manual choke lever spring Manual choke lever Wire clamp screw Valve stem locknut Idle vent valve Idle vent valve stem Idle vent valve spring Flange gasket Air horn reinforcing bar Volume restrictor rod Front and rear carburettors connecting coupling Carburettor actuating throttle lever 2376103 901006-K6 901624-K36 2376193 - 2376192 2376103 901006-K6 901624-K36 2376083 2376193 - 2376192 904231-K36 385175 901004-K6 901834-K36 385174 909522-K36 - 904231-K36 385175 901004-K6 901834-K36 385174 909522-K36 P24080 P24081 P12867 9901818-K36 2376078 2376079 2376080 - 904231-K36 385175 901004-K6 901834-K36 385174 909522-K36 2376066 2376064 2376066 2376075 2376039 2376064 2376066 020059 2376081 020059 - Vehicle Part N o Holden HR, HK, HT and HG 186S engines with manual transmissions. Holden HR, HK, HT and HG 186S engines with automatic transmissions. Stamping Model 23-201A and 23-201B WW 23-202, 23202A and 23202B WW Page 144 of 148 Specification Major repair kit Gasket set Main discharge jet (2 off) Main jet (2 off) High speed bleeder (2 off) Power jet Slow-running jet (2 off) Pump jet Needle and seating Needle and seating washer Choke kick diaphragm assembly Choke kick rod Choke kick rod retainer Vacuum hose Air horn screw and lockwasher (4 off) Choke lever and shaft Choke valve screw (2 off) Choke valve Air horn Air horn gasket Fast idle lever Fast idle lever nut lockwasher Fast idle lever nut Lead ball Pump lever Pump lever fulcrum screw Pump rod Pump rod and piston cotter pin (3 off) Vacuum power piston Pump nozzle screw Pump nozzle gasket Pump outlet check ball Power bypass jet gasket 381205 RK696 381505 388562 381206 31 32 27 24 26 21 57 58 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 22 23 25 386208-053NOTE 9 P23985-70 382454 387183 P24594 388592 P10666 389190 389291 389188 389193 909521-K36 483504 P20904 387129 389890 389456 389293 901004-K6 P16571 P18772 387131 387200 389884 901207-K36 386723 388643 P24668 P17030 P19448 Page 145 of 148 28 29 30 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 59 60 61 62 63 64 Fast idle rod retainer Fast idle rod Main body lead ball (3 off) Metering jet plug gasket (2 off) Main metering jet plug (2 off) Main body gasket Throttle body Slow idle screw spring Slow idle screw Fast idle screw Throttle lever and shaft Throttle valve screw (4 off) Throttle valve Throttle valve Idle needle valve spring (2 off) Idle needle valve (2 off) Throttle body screw and lockwasher (2 off) Throttle body screw and lockwasher (2 off) Thermostat lever nut Thermostat lever nut lockwasher Thermostat shaft lever Thermostat lever and shaft Thermostat cover washer (3 off) Thermostat cover screw (3 off) Thermostat cover gasket Thermostat cover assembly Drive plug (2 off) Choke rod Choke rod cotter pin Float and lever Float fulcrum pin Float fulcrum pin spring Float chamber 387124 389294 P18772 383079 386210 388563 483688 387388 387387 387531 388198 P23956 P24172 P24172 P18710 P15478 386094 909522-K36 901818-K36 901002 386799 386981 P23932 389883 386797 483509 385937 386801 901199-K1 386154 P23272 P23273 387583 483689 Page 146 of 148 65 66 67 68 69 70 71 72 73 74 75 76 - baffle Pump inlet check ball Pump bottom spring Pump duration spring Spring retainer washer Spring clip washer Pump piston assembly Idle vent washer Choke kick diaphragm screw (2 off) Dashpot nut Dashpot bracket Dashpot bracket screw and lockwasher (2 off) Dashpot Main body assembly Hot air restrictor wire P22322 388672 386089 P22046 P22045 483666 388476 386804 901713-K7 388202 909522-K36 386498 389887 2376367NOTE 8 Page 147 of 148 14 Contacts The businesses listed below have not reviewed or approved the information above, nor are they the sole source of materials – I have listed them here as I have found them to be professional sources of early Holden Stromberg parts and/or information. Carburettor Service Company Address: 240 Parramatta Road Burwood, NSW 2134 Australia Telephone: (02) 97474066 Facsimile: (02) 97474803 Email:
[email protected] Internet: www.carburettorservice.com.au Rocket Industries Address: 40 Huntingwood Drive Huntingwood, NSW 2148 Australia Telephone: (02) 88251944 Facsimile: (02) 88251922 Email:
[email protected] Internet: www.rocketind.com Stromberg Carburetor Address: Unit 2, Seven Acres Business Park, Newbourne Road, Waldringfield, Suffolk IP12 4PS, England Telephone: (+44) 1473 811700 Email:
[email protected] Internet: http://www.stromberg-97.com American Auto Parts Address: Unit 2, 22 Rowood Road Prospect, NSW 2148 Australia Telephone: (02) 9769 0655 Facsimile: (02) 9769 0633 Email:
[email protected] Internet: https://www.americanautos.com.au Speco Thomas Pty Ltd Address: 1B Levanswell Road Moorabbin, VIC 3189 Australia Telephone: (03) 95557244 Facsimile: (03) 95532841 Email:
[email protected] Internet: http://www.speco.com.au Page 148 of 148