SESV1622 320 HEX.pdf

Service TrainingMeeting Guide 622 SESV1622 July 1992 TECHNICAL PRESENTATION 320 HYDRAULIC EXCAVATOR 3066 ENGINE 320 HYDRAULIC EXCAVATOR 3066 ENGINE MEETING GUIDE 622 SLIDES AND SCRIPT AUDIENCE Level II - Service personnel who understand the principles of machine systems operation, diagnostic equipment, and procedures for testing and adjusting. CONTENT This presentation covers the 3066 engine as configured for the 320 Hydraulic Excavator. This presentation provides an orientation to all of the 3066 engine systems and describes system operation and in-chassis testing and adjusting of the fuel system. OBJECTIVES After learning the information in this presentation, the serviceman will be able to: 1. locate service points on the 3066 Engine; 2. explain the operation of the fuel pump and governor; 3. explain the interface between the engine and the electronic control unit; and 4. perform in-chassis adjustments to the fuel system. SUPPLEMENTARY TRAINING MATERIAL STMG 619 "320/330 Hydraulic Excavators -- Pumps and Pump Controls" SESV1619 STMG 620 "320/330 Hydraulic Excavators -- Hydraulic Systems Operation" SESV1620 STMG 621 "320/330 Hydraulic Excavators -- Electronic Control Unit" SESV1621 Estimated Time: 2 Hours Visuals: 52 (2 X 2) Slides Serviceman Handouts: 6 line drawings Form: SESV1622 Date: 7/92 © 1992 Caterpillar Inc. STMG 622 - 3 - 7/92 TABLE OF CONTENTS INTRODUCTION.....................................................................................................................................5 AIR INDUCTION AND EXHAUST SYSTEM.......................................................................................7 LUBRICATION SYSTEM......................................................................................................................12 COOLING SYSTEM..............................................................................................................................21 FUEL SYSTEM......................................................................................................................................25 Component Location .........................................................................................................................25 Fuel Pump Operation.........................................................................................................................28 Governor Control System Operation.................................................................................................35 IN-CHASSIS FUEL SYSTEM TESTS AND ADJUSTMENTS ...........................................................46 High and Low Idle.............................................................................................................................46 Idling Sub-spring and Full Load........................................................................................................47 Fuel Nozzle Test ................................................................................................................................50 Fuel Timing .......................................................................................................................................52 Fuel Pump and Governor Removal ...................................................................................................57 CONCLUSION .......................................................................................................................................60 SLIDE LIST ............................................................................................................................................61 SERVICEMAN'S HANDOUTS..............................................................................................................63 STMG 622 - 4 - 7/92 INSTRUCTOR NOTES STMG 622 - 5 - 7/92 • 320 Hydraulic Excavator with 3066 engine • Water cooled, 4-stroke turbocharged, 6 cylinder 1 INTRODUCTION The Caterpillar 3066 engine provides power for the 320 Hydraulic Excavator. This presentation will discuss the air inlet and exhaust, lubrication, cooling, and fuel systems of the 3066 engine. The 3066 engine is a water cooled, four-stroke, turbocharged, in-line six cylinder diesel engine. The 3066 engine in the 320 Hydraulic Excavator produces 97 kW (130 horsepower) at 1800 rpm. STMG 622 - 6 - 7/92 • Hydraulic pumps 1. Power shift hose 2. Proportional reducing valve solenoid harness 2 The engine drives the variable displacement, axial piston, tandem hydraulic pumps. NOTE: This slide shows the power shift pressure hose (1) and the proportional reducing valve solenoid wire harness (2). 2 1 STMG 622 - 7 - 7/92 • Canister-type dry filtering air filter 3 AIR INDUCTION AND EXHAUST SYSTEM Air flows through this canister-type dry filtering air filter before reaching the turbocharger. The air filter is behind the access door on the left side of the engine. STMG 622 - 8 - 7/92 • Replace air filter when indicator (arrow) shows red 4 When dirt plugs the air filter element, engine performance can decrease. The air filter indicator (arrow) shows when the air filter requires servicing. When replacement of the air filter is necessary, the air filter indicator will show red in the indicator window. STMG 622 - 9 - 7/92 • Air intake system components: 1. Turbocharger impeller 2. Exhaust manifold 3. Turbocharger turbine • "Boost" definition 5 After flowing through the air filter, air enters the inlet side (impeller) of the turbocharger (1). The turbocharger forces air through the inlet manifold and into each cylinder chamber during the engine intake stroke. After combustion, the exhaust valve opens and the piston forces the exhaust gasses out of the cylinder, through the exhaust manifold (2) and into the exhaust side (turbine) of the turbocharger (3). The momentum of the gas from the exhaust stroke spins the turbine and causes the impeller to force more air into the inlet manifold. The air pressure in the inlet manifold is referred to as "boost." Boost pressure can give an indication of engine performance. If boost pressure is low, the engine will not produce rated horsepower under full load conditions. Likewise, if the engine is not producing rated horsepower under full load conditions, boost pressure will be low (even if the problem is not in the air intake and exhaust system). 1 2 3 STMG 622 - 10 - 7/92 • Inlet manifold heater (arrow) 6 During cold weather, diesel engines are sometimes difficult to start because the compression stroke cannot sufficiently heat the cold inlet air enough to allow complete fuel combustion. To increase engine startability during cold weather, the 3066 engine can be ordered with an optional inlet manifold air heater (arrow). When in use, the inlet manifold heater heats the inlet manifold and the inlet air before the air enters the cylinders. Do not use ether with this attachment. Using ether with the inlet manifold heater could cause engine damage as well as personal injury or death. WARNING STMG 622 - 11 - 7/92 • Turn key to left (arrow) to activate inlet manifold heater 7 Turning the key switch to the left position (arrow) activates the inlet manifold heater. After heating the inlet manifold air for approximately 30 seconds, an indicator light in the control panel turns ON. After the indicator light turns ON, the operator should start the engine. The inlet manifold heater is on only when the key is in the left position. STMG 622 - 12 - 7/92 • Gear-type oil pump (arrow) 8 LUBRICATION SYSTEM A timing gear drives the gear-type oil pump (arrow). The oil pump circulates oil through the engine to provide cooling, cleaning, protection, sealing, and lubrication. Correct maintenance of the lubrication system is essential to engine life. STMG 622 - 13 - 7/92 • Spin-on oil filter (arrow) • Bypass valve 9 From the oil pump, oil flows to the spin-on oil filter (arrow). As with the air filter, oil filters should be correctly maintained. A plugged oil filter causes increased oil pressure between the pump and the filter. When oil pressure between the pump and filter increases above a specified pressure, the bypass valve inside the oil filter (the bypass valve is not in the filter manifold) allows oil to flow around the filter to the remaining components in the lubrication system. When oil bypasses the filter, the oil pump delivers unfiltered oil to the engine components. STMG 622 - 14 - 7/92 • Oil cooler 10 Oil from the oil filter flows through the oil cooler. Engine coolant provides cooling for the oil. STMG 622 - 15 - 7/92 • Shim adjustable oil pressure relief valve (arrow) 11 When pressure in the lubrication system reaches 343 kPa (50 psi), the relief valve (arrow) will open and vent the excess flow back to the oil pan. This valve provides the main relief for the lubrication system. The lubrication system relief valve is shim adjustable. STMG 622 - 16 - 7/92 • Protective valve (arrow) is a backup to the relief valve 12 If the main lubrication system relief valve does not open, the increased operating pressure can cause engine component damage. To limit the possibility of engine damage due to a malfunctioning relief valve, the 3066 lubrication system contains a backup for the relief valve. The protective valve (arrow) is inside the oil pan on the bottom of the engine cylinder block. The protective valve will open if the lubrication system oil pressure increases to 981 ± 98 kPa (142 ± 14 psi). STMG 622 - 17 - 7/92 • Lubrication system oil pressure tap (arrow) 13 The 3066 engine has a pressure tap (arrow) that allows the lubrication system oil pressure to be measured. This pressure tap is on the side of the engine toward the rear of the machine. The lubrication oil pressure should be between 196 and 392 kPa (28 and 57 psi) with the engine running at 1500 rpm. STMG 622 - 18 - 7/92 • Lubrication oil pressure sensor (arrow) 14 A pressure sensor (arrow) monitors the lubrication oil pressure. When the lubrication oil pressure is not within specifications, the pressure sensor signals the machine monitoring system to warn the operator. STMG 622 - 19 - 7/92 • Engine oil dipstick (arrow) 15 The dipstick (arrow) indicates the engine oil level. STMG 622 - 20 - 7/92 • Engine oil fill port (arrow) 16 If the dipstick indicates that the oil level is low, add oil through the oil fill port (arrow) on top of the engine. STMG 622 - 21 - 7/92 • Conventional radiator • Pressurized cap (arrow) 17 COOLING SYSTEM As in the lubrication system, correct maintenance of the cooling system is essential to machine life. Cooling system problems cause a large number of engine failures. The radiator serves as the reservoir and heat exchanger for the engine coolant. The 320 Hydraulic Excavator has a conventional radiator with an overflow bottle. The pressurized cap (arrow) should never be removed when the engine is hot. At operating temperatures, the engine coolant is hot and under pressure. The radiator and all lines to heaters or the engine contain hot water or steam. Any contact can cause severe burns. Steam can cause personal injury. Check the coolant level only after the engine has been stopped and the filler cap is cool enough to remove with your bare hand. Remove the cooling system filler cap slowly to relieve pressure. Cooling system conditioner contains alkalis that can cause personal injury. Avoid contact with the skin and eyes and do not drink. Allow cooling system components to cool before draining. When draining the cooling system, catch all of the coolant in a suitable container and dispose of coolant in an environmentally sound manner. WARNING STMG 622 - 22 - 7/92 • Radiator overflow bottle 18 The radiator overflow bottle collects engine coolant if the engine temperature exceeds the boiling point of the coolant. Lines on the bottle indicate when the cooling system is full and when the system needs additional coolant. STMG 622 - 23 - 7/92 • Centrifugal-type water pump (arrow) 19 The belt and pulley system drives the centrifugal-type water pump (arrow) and fan. The water pump circulates the coolant through the engine. STMG 622 - 24 - 7/92 • Coolant temperature regulator (arrow) 20 When the coolant temperature is below 71 ± 2° C (160 ± 3.6° F), the coolant temperature regulator (arrow) prevents coolant flow through the radiator. STMG 622 - 25 - 7/92 • Fuel system components: 1. Transfer pump 2. Priming pump • Priming procedure 21 FUEL SYSTEM Component Location A piston-type fuel transfer pump (1) delivers fuel from the tank to the main fuel pump. The fuel camshaft drives the fuel transfer pump. If the machine runs out of fuel or the filter is changed, the fuel priming pump (2) can be used to prime the fuel system. To prime the fuel system, unlock the priming pump by turning the pump knob in the counterclockwise direction. After unlocking the knob, operate the pump. Loosen the air vent plugs on the fuel filter manifold to prime the filter and on the governor to prime the main pump and fuel lines (discussed later). 1 2 STMG 622 - 26 - 7/92 • Fuel filter is downstream from transfer pump • Always use the priming pump to prime system • Open air vent plug (arrow) when priming • Install gauge in air vent plug (arrow) to check fuel pressure 22 The fuel flows through a filter before entering the main fuel pump. The spin-on fuel filter should be maintained at regular intervals. If dirt and debris plug the fuel filter, the filter bypass valve opens and allows the transfer pump to supply unfiltered fuel to the main fuel pump. NOTICE When installing a new fuel filter, never pour fuel into the filter to prime the fuel system. To ensure that no unfiltered fuel enters the fuel system during a filter change, always use the fuel priming pump to prime the fuel system. When priming, open the air vent plug (arrow) to allow air to escape from the system. The system is primed when fuel flows from the air vent plug without air bubbles. Be sure to catch the fuel from the air vent in a suitable container and dispose of it in an environmentally sound manner. Replacing the air vent plug with a pressure gauge measures fuel pressure between the transfer pump and the filter. STMG 622 - 27 - 7/92 • Fuel pump and governor components: 1. Main fuel pump 2. Scroll-type fuel pump 3. Governor 4. Governor actuator mechanism 5. Shutoff solenoid 6. Air vent plug 23 The main fuel pump (1) is an in-line cam-type pump consisting of six individual scroll-type fuel pumps (2). A gear which is timed to the engine crankshaft drives the main fuel cam. The governor (3) controls the amount of fuel that the individual fuel pumps deliver to the cylinders through a fuel control rack. The governor is electro-mechanically actuated through a cable and pulley system (4). When energized, the shutoff solenoid (5) moves the fuel rack to the FUEL OFF position regardless of throttle position. NOTE: When priming the fuel pump and fuel lines, loosen the air vent plug (6). The system is primed when fuel flows from the air vent plug without air bubbles. Be sure to catch the fuel from the air vent in a suitable container and dispose of it in an environmentally sound manner. 1 2 3 4 5 6 24 STMG 622 - 28 - 7/92 • Fuel system diagram • Excess fuel returns to tank through fuel return line FUEL FILTER FUEL INJECTION NOZZLES FUEL OVERFLOW LINE CHECK VALVE FUEL INJECTION PUMP FUEL TRANSFER AND PRIMING PUMPS FROM FUEL TANK TO FUEL TANK FUEL RETURN LINE 3066 FUEL SYSTEM Fuel Pump Operation This slide shows the flow through the fuel system. The fuel transfer pump delivers fuel from the tank to the fuel filter. The fuel filter cleans the fuel before it enters the main pump. The main pump contains six individual fuel pumps. Each individual fuel pump delivers high pressure fuel to a fuel injection nozzle through a fuel line. The fuel nozzles spray atomized fuel into the cylinders. The fuel transfer pump supplies more fuel to the main fuel pump and the individual cylinder fuel pumps supply more fuel to the injector nozzles than the engine needs. The excess fuel delivered to the main pump and injection nozzles serves a lubrication, cooling and cleaning function before returning to the tank through the fuel return line. 25 STMG 622 - 29 - 7/92 • Camshaft drives the transfer pump • Piston chamber spring returns piston to bottom • Discharge check valve closes and suction valve opens FUEL TRANSFER AND PRIMING PUMPS SUCTION CHECK VALVE SUCTION PISTON CAMSHAFT TAPPET DISCHARGE CHECK VALVE PRIMING PUMP The camshaft drives the transfer pump. A tappet and pushrod assembly converts the rotational motion of the camshaft to reciprocating motion. The pushrod moves the piston. The reciprocating motion of the piston creates alternating suction and discharge cycles. As the tappet moves down the cam lobe, the piston chamber spring returns the piston to the bottom position. The returning motion of the piston forces the fuel in the bottom of the piston chamber into the fuel injection pump supply line and also creates decreased pressure in the piston spring chamber. The pressure in the discharge line is now higher than the pressure in the piston spring chamber, and the discharge check valve closes. The decreased pressure in the piston spring chamber also allows the suction check valve to open allowing fuel from the tank to fill the chamber. 26 STMG 622 - 30 - 7/92 • Tappet motion forces piston to compress spring • Suction valve closes and discharge valve opens • Piston spring returning action pumps the fuel FUEL TRANSFER AND PRIMING PUMPS DISCHARGE CHECK VALVE SUCTION PISTON CAMSHAFT TAPPET DISCHARGE CHECK VALVE PRIMING PUMP As the cam lobe pushes the tappet up, the piston compresses the piston chamber spring. As the piston raises, the motion creates an increased pressure in the piston spring chamber. The increased pressure in the piston spring chamber closes the suction check valve and opens the discharge check valve. Fuel flowing by the discharge check valve fills the chamber under the piston (some fuel also enters the fuel injection pump supply line) until the tappet reaches the peak of the cam lobe. As the tappet starts to descend the cam lobe, the piston spring returns the piston to the bottom of the chamber and forces the fuel in the chamber out the discharge port into the fuel injection pump supply line. 27 STMG 622 - 31 - 7/92 • Transfer pump provides a regulating function FUEL TRANSFER AND PRIMING PUMPS REGULATING CHECK VALVE SUCTION PISTON CAMSHAFT TAPPET DISCHARGE CHECK VALVE PRIMING PUMP If the fuel discharge pressure increases abnormally, the fuel pressure in the chamber under the piston can counteract the piston chamber spring force. When the fuel pressure in the chamber under the piston and the spring force reach the equilibrium point, the piston will not continue to descend the cam lobe with the tappet, the fuel pressure inside the spring chamber closes the suction check valve, and the fuel discharge pressure keeps the discharge check valve closed. In this condition, the fuel transfer pump provides a regulating function. 28 STMG 622 - 32 - 7/92 • Sectional view of individual fuel pump • Spring and tappet force plunger to follow camshaft lobe • Fuel pressure overcomes delivery valve spring • Control rack controls fuel injection quantity • Plunger rotates with the sleeve • Control rack movement rotates plunger FUEL INJECTION PUMP TO NOZZLE DELIVERY VALVE HOLDER DELIVERY VALVE SPRING DELIVERY VALVE PUMP HOUSING FUEL CHAMBER CONTROL RACK CONTROL SLEEVE PLUNGER SPRING TAPPET CAMSHAFT PLUNGER CONTROL PINION SUCTION AND DISCHARGE PORT PLUNGER BARREL The fuel from the transfer pump flows through a filter to the main fuel injection pump. This slide shows a sectional view of an individual fuel pump within the main fuel injection pump. The plunger spring and tappet force the plunger to follow the contour of the rotating camshaft lobe. As the camshaft rotates, the tappet moves up the cam lobe, compresses the spring, and forces the plunger upward. As the plunger moves up, fuel pressure in the chamber above the plunger overcomes the delivery valve spring force and delivers fuel to the fuel injection nozzle. The control rack position determines the amount of fuel that the pump can deliver to the injection nozzles. The governor controls the control rack position (discussed later). Each individual fuel pump is connected to the control rack through the control pinion. The control pinion clamps to the control sleeve. Slots inside the control sleeve allow the plunger to slide up and down in the sleeve and in the plunger barrel. The slots in the control sleeve will not allow the plunger to rotate within the sleeve, but force the plunger to rotate with the sleeve. Movement of the control rack, therefore, causes the plunger to rotate with the control sleeve while the plunger barrel remains fixed. 29 STMG 622 - 33 - 7/92 • Effective stroke definition • Injection ends after scroll is open to discharge port PLUNGER BARREL PLUNGER EFFECTIVE STROKE HELIX SUCTION AND DISCHARGE PORT DELIVERY STARTS DELIVERY ENDS FUEL INJECTION PLUNGER EFFECTIVE STROKE As the governor moves the control rack, the movement changes the effective stroke of the plunger which changes the amount of fuel injected. The effective stroke is the distance the plunger moves up from the point where the top of the plunger closes the suction and discharge port to the point where the scroll opens the suction and discharge port. After the scroll opens the suction and discharge port, pressure above the plunger decreases. The decreased pressure above the plunger allows the delivery valve spring to close the delivery valve and end fuel injection, even if the plunger continues to move up. 30 STMG 622 - 34 - 7/92 • Main pump supplies fuel to fuel injection nozzles • Injection pressure is shim adjustable NOZZLE BODY SHIM PRESSURE SPRING PRESSURE PIN TIP PACKING PIN NOZZLE TIP RETAINING NUT FUEL INJECTION NOZZLE The main fuel injection pump supplies high pressure fuel to the fuel injection nozzle through the injection lines. When the pressure in the injection lines reaches 22065 to 23046 kPa (3200 to 3342 psi), the nozzle will inject fuel into the combustion chamber. Injection pressure can be changed by changing the thickness of the shim behind the pressure spring in the fuel injection nozzle. A 0.1 mm (0.004 in.) change in shim thickness causes a 1373 kPa (200 psi) change in the injection pressure. 31 STMG 622 - 35 - 7/92 • Engine starts to overspeed • Flyweights move out • Sleeve and shifter compress torque control spring • Tension lever moves right • Spring and flyweight force equalizes CONTROL RACK GOVERNOR SPRING SWIVEL LEVER CAMSHAFT FLYWEIGHTS SHIFTER AND SLEEVE CONTROL LEVER FLOATING LEVER LOW IDLE STOP IDLING SUB-SPRING TENSION LEVER TORQUE CONTROL SPRING FULL LOAD ADJUSTMENT SCREW NO LOAD MAXIMUM SPEED GOVERNOR OPERATION SHUTOFF LEVER Governor Control System Operation This illustration shows governor operation when the engine speed starts to exceed the speed that the throttle control lever specifies. As the engine starts to overspeed, the centrifugal force of the flyweights causes the flyweights to move out. As the flyweights move out, the shifter and sleeve move to the right until contacting and compressing the torque control spring. After the sleeve and shifter compresses the torque control spring, the tension lever moves to the right. Moving the tension lever to the right stretches the governor spring. Stretching the governor spring increases the tension of the spring. The spring tension and the centrifugal force of the flyweights will eventually reach an equilibrium point and the tension lever will stop moving. STMG 622 - 36 - 7/92 • Floating lever moves to right • Control rack moves to right until spring and flyweight force equalizes • Tension lever contacts idling sub- spring • Torque control spring limits black smoke • Moving rack to left is FUEL ON At the same time that the flyweights, shifter, and sleeve are moving the tension lever, they are also moving the floating lever to the right. The mechanical linkage connecting the floating lever to the control rack moves the control rack to the right. Moving the control rack to the right decreases the amount of fuel that the fuel injection pump supplies to the fuel injection nozzles. The control rack will continue to move to the right until the governor spring and the flyweights reach the equilibrium point. If engine speed continues to increase, the tension lever continues to move to the right until it contacts the idling sub-spring. After the tension lever compresses the idling sub-spring, the control rack is in the NO LOAD MAXIMUM SPEED condition. The function of the torque control spring is to limit the amount of black smoke the engine produces during acceleration. When the engine speed is low, the torque control spring force is larger than the centrifugal force of the flyweights. The spring force moves the shifter and sleeve to the left. Moving the shifter and sleeve to the left moves the guide and floating levers to the left causing the control rack to move toward the FUEL ON direction. As the engine speed increases, the centrifugal force of the flyweights compresses the torque control spring. The shifter will then contact and move the tension lever to decrease the fuel injection quantity. In this governor, pushing the rack in decreases fuel and pulling the rack out increases fuel. NOTE: The control lever and shutoff lever in this illustration are not the actual mechanisms on the 3066 engine in the 320 Hydraulic Excavator. The actual throttle control mechanism on the 3066 engine in the 320 Hydraulic Excavator is not a lever, but rather, a pulley and cable system. The shutoff lever is a solenoid operated control. STMG 622 - 37 - 7/92 •Controller location 32 All of the electrical inputs for engine speed control go through the controller. The controller is on the left side of the machine, behind the same access door as the air filter canister. 33 STMG 622 - 38 - 7/92 • Governor control inputs: 1. AEC switch 2. Power mode switch 3. Engine speed dial 4. Hydraulic pressure switches 5. One-touch low idle switch 6. Backup switches 7. Feedback sensor • Controller signals governor motor MONITOR ENG. SPEED DIAL TRAV. PRESS. SWITCH BM. UP PRESS. SWITCH IMPL. /SW. PRESS. SWITCH LOW IDLE SWITCH SPEED CHANGE SWITCH SPD. DIAL BACKUP SW. ENGINE PUMP G/A FUSE BOX START SWITCH SPEED SENSOR BATTERY ECU (CONTROLLER) G/A FDBK SENSOR ELECTRONIC CONTROL SYSTEM ENGINE SPEED INPUT COMPONENTS This simplified schematic of the machine control system shows only the input components that control the governor motor. The input components are the automatic engine speed control (AEC) and the power mode functions in the control panel; the engine speed dial; the implement/swing, travel, and attachment pressure switches; the one-touch low idle switch on the right implement control lever; the backup switch for the throttle control; and the position feedback sensor in the governor actuator motor. The controller compares the input signal from the engine speed dial to the input signal it receives from the position feedback sensor. If the position feedback sensor and the engine speed dial do not agree, the controller signals the governor motor to move the governor control lever to the correct position. NOTE TO THE INSTRUCTOR: For a complete, detailed description of how the electronic control system operates, see STMG 621 "320/330 Hydraulic Excavators — Electronic Control Unit" (Form SESV1621). STMG 622 - 39 - 7/92 • Governor actuator motor location (arrow) 34 The governor actuator motor (inside metal box, arrow) is on the left side of the machine behind the access door. The governor actuator motor receives electrical signals from the controller. STMG 622 - 40 - 7/92 • Position feedback sensor (arrow) 35 The governor control cables wrap around a pulley that is connected to the position feedback sensor (arrow) in the governor actuator motor. Electrical signals to the governor actuator motor cause the feedback sensor and pulley to rotate. The rotating pulley moves the cable which in turn moves the governor throttle control lever. STMG 622 - 41 - 7/92 • Engine speed control dial location 36 The engine speed control dial in the operator’s station is one of the input components that control engine speed. The engine speed control dial has ten positions. Each position corresponds to a specific engine rpm. Position 1 is LOW IDLE and position 10 is HIGH IDLE. STMG 622 - 42 - 7/92 • Engine speed backup switches allow LOW and HIGH IDLE operation 1. Auto/manual switch 2. Speed toggle switch • Possible to operate at an intermediate speed 37 The engine speed control circuit contains backup switches (located in the operator’s station, under a cover, at the rear of the right arm rest) which allow the operator to bypass the engine speed dial. To operate the engine at LOW IDLE, position the manual/auto switch (1) in the "MAN" position and hold the two-position, spring-centered speed toggle switch (2) toward the "Tortoise" until the engine speed stops decreasing. To operate the engine at HIGH IDLE, hold the speed switch (2) toward the "Rabbit" until the engine speed stops increasing. To operate the engine at an intermediate speed, release the speed toggle switch before the engine reaches either high or low idle. 1 2 STMG 622 - 43 - 7/92 • Two levels of AEC 1. AEC switch 2. Power mode selector switch • First level AEC operates with AEC switch (1) OFF • Second level AEC operates with AEC switch ON and engine speed dial above 5 • Power mode switch (2) determines engine rpm • Each power mode level corresponds to an engine speed dial position 38 The AEC function improves fuel consumption and noise level by reducing engine speed during no load conditions. The AEC function has two levels of operation. The first level operates when the AEC switch (1) is OFF. The first level occurs approximately three seconds after the engine load requirements stop. The swing, travel, and attachment pressure switches send signals to the controller which tell the controller when engine load requirements end. When the load requirements end, the controller signals the governor motor to reduce the engine speed by approximately 100 rpm. The second AEC level occurs only when the AEC switch is ON and the engine speed dial is at 5 or above. The second level automatically reduces engine speed to approximately 1300 rpm if, after 3 seconds, the engine does not encounter a load. When one of the pressure switches turns ON (loaded condition), the engine speed returns to the speed that the speed dial indicates. The power mode selector switch (2) is also in the control panel. The power mode level determines the maximum engine speed independently of engine speed dial position. Power Mode III allows the full range of throttle operation (engine speed dial positions 1-10). Power Mode II limits the maximum engine speed to position 9 and Power Mode I limits maximum engine speed to position 7, regardless of the engine speed dial position. The machine defaults to Power Mode II at start-up. 1 2 39 STMG 622 - 44 - 7/92 • Engine rpm with machine in Power Mode III and engine speed dial at 10 • Three seconds after removing load, AEC controls engine speed • Engine stays at AEC level until machine encounters a load 900 1100 1300 1500 1700 1900 5 10 15 HIGH IDLE AUTOMATIC ENGINE CONTROL E N G I N E R P M TIME (SEC) AEC SWITCH OFF AEC SWITCH ON This graph shows the engine rpm during various conditions of implement operation with the machine in Power Mode III and the engine speed dial at position 10. The first 5 seconds of the graph shows engine rpm while operating an implement. During this time, the engine is under varying loads and, therefore, the rpm will fluctuate. When the operator removes the load from the engine, the engine speed momentarily increases to HIGH IDLE. If the AEC switch is OFF, approximately three seconds after reaching HIGH IDLE, the first level AEC function decreases the engine speed by 100 rpm. If the AEC switch is ON, approximately three seconds after the engine reaches HIGH IDLE, the second level AEC function decreases the engine rpm from high idle to 1300 rpm. As long as the operator does not move an implement or operate a travel motor, the engine speed remains at approximately 100 rpm below HIGH IDLE (AEC switch OFF) or at 1300 rpm (AEC switch ON). When the operator puts a load on the engine, the controller returns the engine speed to either the engine speed dial setting or the maximum speed that the power mode level allows (whichever is lowest). STMG 622 - 45 - 7/92 • One-touch low idle switch (arrow) • Loading the machine automatically returns engine to normal operating rpm 40 The right implement control lever contains the one-touch low idle switch (arrow). When the operator activates the one-touch low idle switch, the controller signals the governor motor to reduce the engine speed to approximately 940 rpm. When the operator pushes the switch a second time, engine speed increases to either the engine speed dial level, the power mode level, or the AEC level (whichever is lowest). If the operator activates a function, the one-touch low idle control switch will automatically turn OFF and engine speed returns to the normal operating rpm level. NOTICE The engine speed dial should be in position 1 before the engine is shut down. If the operator turns the machine OFF with the one-touch low idle switch active (engine speed at approximately 940 rpm) and does not return the engine speed dial to position 1 before the machine is restarted, upon restarting, the engine speed will accelerate to the engine speed dial setting or the Power Mode II level -- whichever is lowest. The controller DOES NOT retain memory that the one-touch low idle switch was active at engine shutdown. STMG 622 - 46 - 7/92 1. High idle screw 2. Low idle screw 41 IN-CHASSIS FUEL SYSTEM TESTS AND ADJUSTMENTS High and Low Idle The high idle (1) and low idle (2) screws adjust maximum and minimum engine speed. The high idle speed specification for the 320 Hydraulic Excavator with the 3066 engine is 1970 + 30 -20 rpm and the low idle speed specification is 800 ± 50 rpm. Turning the high idle screw clockwise decreases the engine rpm at HIGH IDLE and turning the screw counterclockwise increases engine rpm at HIGH IDLE. Turning the low idle screw clockwise increases the engine rpm at LOW IDLE, while turning the low idle screw counterclockwise decreases the engine rpm at LOW IDLE. NOTICE The first level AEC function makes it difficult to directly test engine HIGH IDLE speed on the machine with the controller signaling the governor actuator motor. First level AEC reduces the engine speed to approximately 100 rpm below the HIGH IDLE speed regardless of whether the AEC switch is ON or OFF. Therefore, never adjust the HIGH IDLE speed with the engine connected to the controller. To check HIGH IDLE, use the backup switch (discussed earlier). 1 2 STMG 622 - 47 - 7/92 • Governor components: 1. Idling sub-spring 2. Torque control spring 3. Full load adjustment screw • Idling sub-spring maintains constant engine rpm at LOW IDLE • Adjusting idling sub- spring can cause engine to overspeed • Full load adjustment screw limits rack travel 42 Idling Sub-spring and Full Load This view of the governor shows the access cover to the idling sub-spring (1), the torque control spring (2, behind cover), and the full load adjustment screw (3). The function of the idling sub-spring is to maintain a constant engine rpm at LOW IDLE. If the engine rpm fluctuates abnormally at LOW IDLE, the idling sub-spring may not be in contact with the governor tension lever allowing the control rack position to float. Tightening the idling sub-spring adjusting screw until the spring just contacts the tension lever prevents the control rack position from floating. With the idling sub- spring applying some force on the tension lever, the low idle speed will increase slightly but will stop fluctuating. When working the machine, the engine may overspeed after removing a load if the idling sub-spring force against the tension lever is too high. When adjusting the idling sub-spring tension, tighten the adjusting screw just enough to eliminate the unstable LOW IDLE condition. The function of the full load adjustment screw is to limit rack travel during FULL LOAD conditions. The full load adjustment screw provides a positive stop for the floating lever in the governor. Turning the full load adjustment screw clockwise increases the fuel injection quantity while turning the bolt counterclockwise decreases the fuel injection quantity. 1 2 3 STMG 622 - 48 - 7/92 • Cannot measure engine output under full load conditions on standard machine • Standard 3066 engine does not have a boost pressure tap Since the engine produces maximum horsepower when the floating lever contacts the full load adjustment screw (with the engine at full load rpm), a misadjusted full load adjustment screw can cause the engine horsepower to be out of specification. However, engine output cannot be measured under FULL LOAD conditions with a standard 3066 engine in the 320 Hydraulic Excavator because the engine does not have a boost pressure tap and the controller destrokes the hydraulic pumps before the engine reaches full load [see STMG 619 "320/330 Hydraulic Excavators — Pumps and Pump Controls" (Form SESV1619)]. If the engine has a power problem and after checking all other possibilities (such as fuel grade, governor control mechanism functioning correctly, altitude deration, plugged air and fuel filters, air in the fuel lines, fuel nozzles functioning correctly, and correct injection timing), the engine should be tested on a dynamometer. NOTE: With a minor engine modification, it is possible to check engine horsepower with the engine in chassis. This procedure requires drilling a boost pressure tap in the air intake system, disconnecting the controller signal to the hydraulic pumps (either disconnect the proportional reducing valve harness or disconnect and plug the power shift pressure hose), and loading the engine with the swing and bucket hydraulic circuits while measuring engine rpm and boost pressure. To perform this procedure, operate the swing motor against the swing lock pin. Then, slowly load the bucket while measuring the engine speed. When the engine speed decreases to approximately 1700 rpm (100 rpm below full load speed), gradually decrease the bucket load. Decreasing the bucket load will cause an increase in engine rpm and boost pressure. Boost pressure will increase to maximum, then start to decrease. Record the boost pressure and engine speed when the boost pressure is highest. Since the engine produces maximum horsepower at maximum boost pressure, comparing the recorded engine speed and boost pressure with engine specifications will indicate if the engine is producing rated horsepower. Boost pressure at 1800 rpm should be 500 ± 50 mm Hg (9.7 ± 1 psi). If the engine is not producing sufficient boost pressure at FULL LOAD speed, it is also not producing rated horsepower. This test should be used for determining engine performance for troubleshooting purposes only. This test is not accurate enough to make full load screw adjustments. STMG 622 - 49 - 7/92 NOTICE The timing gear housing interferes with the in-chassis rack travel measurement. Currently, there is no way of knowing if adjusting the full load adjustment screw moves the rack travel distance out of specification. Engine dynamometer testing and the fuel test bench provide the safest and most accurate way to adjust engine horsepower. STMG 622 - 50 - 7/92 • Fuel injection nozzle test procedure • Fuel injection nozzle removal procedure: 1. Loosen supply line 2. Loosen return line 3. Loosen bolt and remove clamp 43 Fuel Nozzle Test If engine performance is low, a malfunctioning fuel injection nozzle may be the cause. To test a fuel injection nozzle, operate the engine at HIGH IDLE (using the engine speed dial bypass switches) and measure the engine speed. After recording the HIGH IDLE rpm, loosen the fuel supply line (1) to the suspected injector and direct the fuel flow from the line into a suitable container. With the fuel supply line loose, operate the engine at HIGH IDLE and measure the engine rpm. If the engine speed decreases from the previous HIGH IDLE measurement, the performance problem is probably not related to that injector. If the high idle speed remains the same as before disconnecting the fuel supply line, remove the injector and test it on a nozzle test stand. If the injector is defective, either repair or replace it. Then, recheck the engine performance. To remove a fuel injection nozzle, loosen the fuel return line (2) from each injector and remove the line. After removing the return line, loosen the bolt (3) and remove the clamp. The injector should pull straight out of the head. If the injector does not slide out of the head easily, use a wrench to turn the injector while pulling the injector out. 1 2 3 STMG 622 - 51 - 7/92 Never allow the fuel from the fuel line to spill on the hot engine or on the ground. Engine heat may be sufficient to cause fuel combustion which could result in personal injury and property damage. Diesel fuel is a hazardous material and must not be allowed to contaminate the environment. WARNING STMG 622 - 52 - 7/92 • Engine timing gears 1. TDC reference mark 2. TDC reference mark 3. Fuel timing gear 44 Fuel Timing Incorrect fuel injection timing can cause low engine performance. The engine timing gears have reference marks (1 and 2) that mesh when the No. 1 cylinder is at top dead center. The fuel timing gear (3) drives the fuel camshaft. Rotating the main fuel pump relative to the fuel timing gear changes fuel injection timing 1 2 3 STMG 622 - 53 - 7/92 1. Scale 2. Retaining bolts • Scale indicates fuel pump position • Each mark represents a 6° timing change 45 This scale (1) on the injection pump indicates the position of the main fuel pump relative to the timing gear. Each mark on the scale represents a 6° timing change. Loosening the retaining bolts (2) and rotating the top of the pump toward the engine advances the injection timing, while rotating the top of the pump away from the engine retards the injection timing. 1 2 STMG 622 - 54 - 7/92 • Fuel injection timing test procedure 1. Fuel line 2. Clamp 46 To check the fuel injection timing, disconnect the fuel line (1) from the No. 1 fuel pump. Loosen the clamp (2) and remove the delivery valve holder. Remove the valve and spring from the delivery valve holder; then, replace only the holder (see slide 28). Attach a spare injection line to the No. 1 fuel pump and place the end of the pipe in a container suitable for holding diesel fuel. 1 2 STMG 622 - 55 - 7/92 • Rotate crankshaft by turning nut (arrow) 47 After preparing the No. 1 fuel pump, use a socket wrench to turn the nut (arrow) and rotate the crankshaft until the No. 1 piston is approximately 60° before top dead center on the compression stroke. NOTE: Checking valve clearances with the number one cylinder at top dead center ensures that the cylinder is on the compression stroke and not the exhaust stroke. STMG 622 - 56 - 7/92 • Each mark on the scale represents 5° of crankshaft rotation • Pointer (arrow) • Injection timing is 16° BTDC 48 The pulley contains a scale that ranges from 0° to 40° and a pointer (arrow). Each mark on the scale represents a 5° crankshaft rotation. While pumping the fuel priming pump, rotate the engine crankshaft until fuel stops flowing and read the number the pointer indicates on the scale. The indicated number is the fuel timing advance. The fuel injection timing specification for the 3066 engine in the 320 Hydraulic Excavator is 16° before top dead center. If the fuel injection timing is not 16° before top dead center, rotate the fuel pump (as previously described) to change the injection timing. STMG 622 - 57 - 7/92 • Bench tests are the most accurate test for fuel pump and governor • Remove bolts (1) to remove pump without timing gear • Remove bolts (2) and (3) to remove pump with timing gear 49 Fuel Pump and Governor Removal The most accurate way to correctly test and adjust the pump and governor is on a test bench. After disconnecting the main fuel supply line, fuel injector supply lines, the fuel overflow line, the lubrication line, and all of the governor control linkages, the pump and governor can be removed. The pump and governor can be removed with or without the fuel timing gear. To remove the pump and governor without the timing gear, loosen the four bolts (1) from the timing gear housing. To remove the pump and governor with the fuel timing gear, remove the five bolts (2) from the timing gear housing cover and loosen the three retaining bolts (3). 1 2 3 STMG 622 - 58 - 7/92 • Taper and slot match timing gear 50 The taper and slot at the end of the fuel camshaft allows the pump and governor to attach to the fuel timing gear in only one position. STMG 622 - 59 - 7/92 • Taper and slot match camshaft 51 The taper and key slot in the timing gear matches the taper and key slot of the fuel camshaft. STMG 622 - 60 - 7/92 52 CONCLUSION This presentation discussed the 3066 engine as configured for use in the 320 Hydraulic Excavator. The information in this presentation should help dealer service personnel understand the engine and how it relates to the machine. 1. Model view 2. Hydraulic pumps 3. Air filter 4. Air filter indicator 5. Turbocharger 6. Inlet manifold heater 7. Key switch 8. Engine oil pump 9. Engine oil filter 10. Engine oil cooler 11. Lubrication system main relief valve 12. Lubrication system backup relief valve 13. Lubrication system oil pressure tap 14. Lubrication system oil pressure sensor 15. Engine oil dipstick 16. Engine oil fill port 17. Radiator 18. Radiator overflow bottle 19. Water pump 20. Temperature regulator 21. Fuel transfer and priming pump 22. Fuel filter 23. Fuel pump and governor 24. Fuel system diagram 25. Fuel transfer and priming pumps illustration - SUCTION 26. Fuel transfer and priming pumps illustration - DISCHARGE 27. Fuel transfer and priming pumps illustration - REGULATING 28. Fuel injection pump illustration 29. Effective stroke illustration 30. Fuel injection nozzle illustration 31. Governor operation illustration - NO LOAD MAXIMUMSPEED 32. Controller 33. Engine speed input components schematic 34. Governor actuator motor 35. Position feedback sensor and full load adjustment screw STMG 622 - 61 - 7/92 36. Engine speed control dial 37. Engine speed control backup switches 38. Electronic control unit 39. AEC operation graph 40. One-touch low idle switch 41. High and low idle adjustment screws 42. Idling sub-spring, torque control spring, 43. Fuel injection nozzle 44. Engine timing gears 45. Fuel timing reference scale 46. No. 1 injection pump 47. Crankshaft rotation nut 48. Timing reference scale 49. Fuel pump and governor removal screws 50. Taper and slot in fuel camshaft 51. Taper and slot in fuel timing gear 52. Model view SLIDE LIST STMG 623 - 62 - Serviceman's Handout No. 1 8/92 F U E L T R A N S F E R A N D P R I M I N G P U M P S S U C T I O N C H E C K V A L V E S U C T I O N P I S T O N C A M S H A F T T A P P E T D I S C H A R G E C H E C K V A L V E P R I M I N G P U M P STMG 623 - 63 - Serviceman's Handout No. 2 8/92 F U E L I N J E C T I O N P U M P T O N O Z Z L E D E L I V E R Y V A L V E H O L D E R D E L I V E R Y V A L V E S P R I N G D E L I V E R Y V A L V E P U M P H O U S I N G F U E L C H A M B E R C O N T R O L R A C K C O N T R O L S L E E V E P L U N G E R S P R I N G T A P P E T C A M S H A F T P L U N G E R C O N T R O L P I N I O N S U C T I O N A N D D I S C H A R G E P O R T P L U N G E R B A R R E L STMG 623 - 64 - Serviceman's Handout No. 3 8/92 N O Z Z L E B O D Y S H I M P R E S S U R E S P R I N G P R E S S U R E P I N T I P P A C K I N G P I N N O Z Z L E T I P R E T A I N I N G N U T F U E L I N J E C T I O N N O Z Z L E STMG 623 - 65 - Serviceman's Handout No. 4 8/92 C O N T R O L R A C K G O V E R N O R S P R I N G S W I V E L L E V E R C A M S H A F T F L Y W E I G H T S S H I F T E R A N D S L E E V E C O N T R O L L E V E R F L O A T I N G L E V E R L O W I D L E S T O P I D L I N G S U B - S P R I N G T E N S I O N L E V E R T O R Q U E C O N T R O L S P R I N G F U L L L O A D A D J U S T M E N T S C R E W N O L O A D M A X I M U M S P E E D G O V E R N O R O P E R A T I O N S H U T O F F L E V E R STMG 623 - 66 - Serviceman's Handout No. 5 8/92 M O N I T O R E N G . S P E E D D I A L T R A V . P R E S S . S W I T C H B M . U P P R E S S . S W I T C H I M P L . / S W . P R E S S . S W I T C H L O W I D L E S W I T C H S P E E D C H A N G E S W I T C H S P D . D I A L B A C K U P S W . E N G I N E P U M P G / A F U S E B O X S T A R T S W I T C H S P E E D S E N S O R B A T T E R Y E C U ( C O N T R O L L E R ) G / A F D B K S E N S O R E L E C T R O N I C C O N T R O L S Y S T E M E N G I N E S P E E D I N P U T C O M P O N E N T S STMG 622 - 67 - Serviceman's Handout No. 6 7/92 9 0 0 1 1 0 0 1 3 0 0 1 5 0 0 1 7 0 0 1 9 0 0 5 1 0 1 5 H I G H I D L E A U T O M A T I C E N G I N E C O N T R O L E N G I N E R P M T I M E ( S E C ) A E C S W I T C H O F F A E C S W I T C H O N SESV1622 Printed in U. S. A. 7/92