Service BulletinVolvo Trucks North America Trucks D Greensboro, NC USA Date Group No. Page This Service Bulletin replaces SB 230–94, “Fuel Supply Pressure, Fault Tracing, Checklist B, D12D” (11.2004), 5.2006 230 94 1(26) publication no. PV776–20 019713. Fuel Supply Pressure Fault Tracing Checklist B D12D Fuel Supply Pressure, Fault Tracing Checklist B W2005417 This information covers fault tracing the fuel supply pressure of the Volvo D12D engine. Contents • “General Guide to Fault Tracing” page 2 • “System Overview” page 3 • “Fuel Supply Pressure, Fault Tracing” page 6 Note: Information is subject to change without notice. Illustrations are used for reference only, and may differ slightly from the actual engine version. However, key components addressed in this information are represented as accurately as possible. PV776-20175552 USA20679.ihval Volvo Trucks North America Date Group No. Page Service Bulletin 5.2006 230 94 2(26) General Guide to Fault Tracing D You must read and understand the precautions and guidelines in Service Information, group 20, "General Safety Practices, Engine" before performing any procedure. If you are not properly trained and certified in a procedure, ask your supervisor for training before you perform it. To use this checklist: 1 • Complete basic data gathering • Read fault codes • Check vehicle parameters 2 Use the recommendations in appropriate symptom information, plus the information gathered above to provide a foundation for continued fault tracing using this checklist. One fault often affects other systems. Therefore, it is important to confirm or eliminate suspected causes of faults at an early stage, using tests in VCADS Pro. Note: Maximum cleanliness should be observed during work with the fuel system. Always wash the engine before starting the work. Protective plugs should be installed where connections have been removed to prevent the fuel system from being contaminated. Removed parts should be kept in a sealed plastic bag until they are installed. it is important to understand the function of the system and to follow the fault-tracing sequence in the checklist to avoid replacing non-defective components.2006 230 94 3(26) System Overview Fuel System: D When fault tracing. . where the fuel from the tank is mixed with the return fuel from the cylinder head fuel gallery (7). page 10 W2005406 System Function A non-return valve (10) is located in the electric fuel pump (3). This gallery supplies each unit injector (9) with fuel via a circular groove in the injector body. This valve ensures that the fuel does not run back to Fuel is drawn up using the supply pump (1) through the tank when the engine is not running. Page Service Bulletin 5. 1: Fuel System D12D Type 1 (With Electric Fuel Priming Pump). and on to the suction side of the fuel pump. past the electric fuel pump (3) into the fuel filter housing (4). The overflow valve (6) regulates the pressure of the fuel supply to the injectors. 2005. • Fuel System D12D Type 1 (With Electric Fuel Priming Pump): See “Fuel System D12D Type 1 (With Electric Fuel Priming Pump)” page 3 • Fuel System D12D Type 2 (With Manual Fuel Priming Pump): See “Fuel System D12D Type 2 (With Manual Fuel Priming Pump. Fuel then proceeds through the EECU cooling plate (5) and up to the overflow valve (6).Volvo Trucks North America Date Group No. the pickup tube(s) in the fuel tank (2) through the water separator/prefilter (not shown). See Fig. The supply pump forces the fuel to the fuel filter housing through the main filter (8) to the cylinder head longitudinal fuel gallery. Version A and B)” page 4 Fuel System D12D Type 1 (With Electric Fuel Priming Pump) Note: Prior to week 6. increases. the air is forced out through the fuel line (14) and on through the air vent valve (15) Bleeding the fuel system: When the switch (13) is down to the fuel tank via the return line (16). Page Service Bulletin 5. Version B. 3: Fuel System D12D Type 2 (With Manual Fuel Priming Pump. Version A and B) Note: After week 6. page 11 W2005407 . the fuel filter. Fuel System D12D Type 2 (With Manual Fuel Priming Pump. e. Electric Fuel Pump The electric fuel pump (3) is used to bleed the fuel system approximately 5 minutes.Volvo Trucks North America Date Group No. During bleeding. It is activated using the fuel system is filled and the pressure in the system the dashboard switch (13). page 10 and Fig.e. This sensor measures the supply pressure after replacing unit injectors for example. 2005 See Fig. when the fuel filter is blocked. during fuel filter replacement). 2: Fuel System D12D Type 2 (With Manual Fuel Priming Pump. pressed. A pressure sensor (18) is also located on the fuel filter The nipple is used for draining the fuel system when housing. the electric fuel pump starts and runs for Other A drain nipple (17) is located on the fuel filter housing. Bleeding takes place when (i.g. The safety valve (11) allows fuel to flow back to the suction side when the pressure is too high. Version A). The non-return valve (12) opens when the electric fuel pump (3) is used. The instrument panel will show a fault code if the supply pressure is less than specifications.2006 230 94 4(26) D Supply Pump Valves Two valves are located in the supply pump (1). The fuel then proceeds through the EECU cooling D plate (6). If additional drainage • The engine is stopped. which monitors the supply pressure after the fuel peg (19) and (23) closes when the fuel filter is removed. the switch (17) remained in the instrument panel and did not change. e. seconds and drains the water. The overflow valve (7) controls the pressure of the fuel to the injectors. the drain valve (18) opens for about 15 indicates high water level. For vehicles built with the Low (fleet) cluster. Purging the air after fuel filter replacement engine starts. wait 6 minutes before repeating. the fuel filter housing is used when measuring supply pressure with an external sensor.2006 230 94 5(26) System Function There are two versions (A and B) of the Type 2 fuel filter housing (see graphic on Fig. if Automatic Bleeding If air gets into the fuel system. 2: Fuel System D12D Type 2 (With Manual Fuel Priming Pump. The supply pump (1) forces the fuel to the fuel filter housing (3) through the main filter (9) to the cylinder head’s longitudinal fuel gallery (8). it is purged when the return line (15). where the fuel from the tank is mixed with the return fuel from the cylinder head fuel gallery (8). following requirements to be fulfilled: When the switch (17) (located in the instrument panel) • The sensor (16) in the water separator bowl (5) is depressed.g. Other The type 2 fuel filter housing eliminates the need to There is also a pressure sensor (21) on the fuel filter drain the fuel when replacing the fuel filter. (14) and (25). is required. The discontinued and the drain function was integrated into the non-return valve (24) for the hand pump is also located in cluster function and controlled by the wiper stalk switch. 2005. During purging. Version B. the switch (17) was not running) after the fuel system has been drained. page 10 and Fig. Note: The hand pump should not be used while the engine is running. Manual Hand Pump The manual hand pump (13) is located on the fuel filter Note: For vehicles equipped with High and Medium housing and is used to pump fuel (when the engine is clusters and built after Nov. since the • Ignition key in drive position. The safety valve (11) allows the fuel to flow back to the suction side when the pressure becomes too high. Version A). . filter. function is on a timer. This gallery supplies each unit injector (10) with pressurized fuel via a circular groove around the unit injector in the cylinder head. page 11 for actual line routing and differences). 3: Fuel System D12D Type 2 (With Manual Fuel Priming Pump. the bleed valve (14) down to the fuel tank via the fuel Water Drainage Draining water from the water separator (4) requires the • The parking brake is applied. The non-return valve (12) opens when the hand pump (13) is used. Page Service Bulletin 5. up to the overflow valve (7). and into the fuel filter housing (3) where it passes through the primary filter (4) and water separator (5). The plugged outlet port (20) on fitted in the lower part of the water separator. A fault code is shown on the instrument panel if the It is no longer necessary to purge the air from the fuel supply pressure is less than the specified value. Supply Pump Valves There are two valves in the supply pump (1): the fuel filter becomes blocked. system after replacing the filter. the air is forced out through is controlled by valves (19). and on to the suction side of the supply pump. Fuel is drawn up the fuel lines via the supply pump (1) through the pickup tube(s) located in the fuel tank (2). since this is performed automatically when the engine is started and runs for A fuel heater (22) is available as an optional extra. The valve housing. It is more than 2 minutes.Volvo Trucks North America Date Group No. the fuel filter housing. 3.” group 2841 . valve(s). go to step 12. 11 (engine won’t run) 2 “Fuel Lines and Connections. Continue fault tracing with next step in the checklist. Supply pressure: “General Guide to Fault Tracing” page 2 “System Overview” page 3 Customer Yes No Idle: kPa (psi) 1400 rpm/full load: kPa (psi) Fault-tracing Symptom Supply pressure.1 If MID 128 PID 94 FMI 7 is active (mechanical fault). Checking” page 9 (using VCADS Pro) Mileage D See also: • • If fault code MID 128 PID 94 FMI 3 or 5 is active (electrical fault). 6. Fault Tracing Chassis Number “Fuel Supply Pressure. Page Service Bulletin 5.Volvo Trucks North America Date Group No. 4. and hose(s) open? Is fuel tank pick-up tube(s) undamaged and open? Action: 4 “Fuel Supply Pressure. 10.2006 230 94 6(26) 1 Vehicle Fuel Supply Pressure. 5. 8. Supply pressure. Checking” page 9 Are the suction and pressure fuel lines and connections intact and properly tightened? Are the fuel lines undamaged and properly clamped and routed? Is the hollow screw in the correct location? Is the correct hollow screw with valve in the proper location? Action: 3 “Fuel Tank. but NOT within specification using VCADS Pro. 9 (OK at idle) Low at idle (OK <100 kPa (14.5 psi) <300 kPa (44 psi) 2.5 psi) >300 kPa (44 psi) 6.5 psi) <300 kPa (44 psi) 2. Action: 1 IMPACT or ID DVD: Info type “Diagnostics. 7. 10 . See steps: idle 1400 rpm/full load Low at full load >100 kPa (14. Checking” page 12 Is there adequate fuel in the fuel tank(s)? Is fuel tank free from contaminants and debris? Are fuel tank air vent(s). 4. 12 No fuel pressure 0 0 2.11 Extremely high >600 kPa (87 psi) >600 kPa (87 psi) 2. Checking (Filtered Side)” page 13 Supply pressure: Idle: kPa (psi) 1400 rpm/full load: kPa (psi) Is the supply pressure correct after the fuel filter? Note: if supply pressure is within specification when measured with external pressure gauge. 3. 3. see MID 128 fault codes. 10 at full load) Always low <100 kPa (14. Volvo Trucks North America Date Group No. Checking” page 25 Is supply pump safety valve and spring fault free? Is non-return valve and spring fault free? Is air vent valve for the return line fault free? Action: 11 “Fuel Supply Pump.2006 230 94 7(26) 5 6 Vehicle Idle: 1400 rpm/full load: Chassis Number “Fuel Supply Pressure. Checking” page 22 Is fuel system free from air on the suction side? Is fuel system free from air on the pressure side? Action: 9 “Water Separator and Pre-filter. Checking” page 18 Measured opening pressure: Customer kPa (psi) kPa (psi) kPa (psi) Yes No Is the overflow valve opening pressure within specifications? Action: 7 “Fuel Restriction. Checking” page 25 Is water separator/prefilter clean and fault free? Action: 10 “Valves. Fuel Supply Pump. Page Service Bulletin 5. Checking” page 26 Is supply pump weep hole open and unplugged? Is supply pump weep hole free of fuel or oil? Is supply pump valve seat free from defects? Is supply pump drive gear/shaft and housing in good condition and free from excessive wear? Is the supply pump drive shaft coupled correctly to the accessory drive? Action: . Checking (Unfiltered Side)” page 16 Supply pressure: D Mileage Is the supply pressure correct before it enters the fuel filter housing? Action: “Overflow Valve. Checking” page 20 Is fuel restriction within normal values? Action: 8 “Air in Fuel System. ground.2006 230 94 8(26) 12 Notes: Vehicle Chassis Number Mileage D 2 MID 128 PID 94. Fuel Supply Pressure Sensor.” group 2841 . Checking (refer to MID 128 fault codes) ) Are sensor power. Page Service Bulletin 5.Volvo Trucks North America Date Group No. and signal wires okay? Is sensor connector okay? Is sensor fault free? Action: Completed by: Dealer: Customer Yes Date: No 2 IMPACT or ID DVD: Info type “Diagnostics. 3 IMPACT or ID DVD: Info type “Diagnostics. Fuel Lines and Connections. Checking (Filtered Side)” page 13). 2 Check that no lines are kinked or show visible damage. Perform “Fuel Supply Pressure Checks” follow instructions in VCADS Pro. If values do not agree.5 psi) at idle • 300 kPa (44 psi) at 1400 rpm/full load Note: If fault code MID 128 PID 94 FMI 3 or 5 is active. 3 Check that the fuel pressure reading in VCADS Pro is approximately the same as readings on pressure gauge ( “Fuel Supply Pressure. Checking” page 22. Possible fault code: MID 128 PID 944. check sensor and wiring. this is not usually seen as external leakage.” group 2841 4 IMPACT or ID DVD: Info type “Diagnostics. and that no seals are damaged. Checking (Using VCADS Pro) 1 Connect the PC tool to the vehicle diagnostics connector. continue fault tracing with next step in the checklist. If fault code MID 128 PID 94 FMI 7 is active. 2 Verify that the supply pressure is at least: • 100 kPa (14. Checking 1 Check whether there is any leakage in the fuel lines or at the fittings.” group 2841 . fuel pressure will not be read in VCADS Pro. Refer to MID 128 fault codes3. However. Page Service Bulletin 5.Volvo Trucks North America Date Group No. 3 Check that the fuel line fittings on the suction side are tight. air can enter the fuel system and cause operational malfunctions. Note: If the fuel line fittings on the suction side are leaking. See “Air in Fuel System.2006 230 94 9(26) D Fuel Supply Pressure. Fault Tracing Fuel Supply Pressure. 2: Fuel System D12D Type 2 (With Manual Fuel Priming Pump. 1: Fuel System D12D Type 1 (With Electric Fuel Priming Pump) 1 Hollow screw only PN: 48634 2 Air bleed pipe with valve PN: 20487131 Check that the hollow screw is installed in the correct location for the type and version fuel system you are working with. . W2005408 Fig.2006 230 94 10(26) D 4 W2005409 Fig. 2 Hollow screw only P/N 48634 (Hollow screw with valve assembly in this location will result in high fuel pressure).Volvo Trucks North America Date Group No. Version A) 1 Hollow screw with Valve assembly PN: 20741620 (Hollow screw only in this location will result in low fuel pressure). Page Service Bulletin 5. however. Note: Both the 20741620 and 20745644 are equipped with a valve.2006 230 94 11(26) D 5 Check that each hollow screw with valve are correct and installed in the proper location for the type and version fuel system you are working with. 6 If any corrective action was taken. For identification purposes. Version B 1 Hollow screw with valve assembly PN: 20741620 2 Hollow screw (only) 3 Hollow screw with valve assembly PN: 20745644 (Low fuel pressure if hollow screw is in this location). they are different. . recheck for any change in supply pressure. W2005410 Fig. Page Service Bulletin 5. 20745644 has a 5 mm tall hex head.Volvo Trucks North America Date Group No. 20741620 has a 8 mm tall hex head. 3: Fuel System D12D Type 2 (With Manual Fuel Priming Pump. Listen to hear whether air enters the tank. use an air nozzle to blow air into the fuel tank vent hose. recheck for any change in supply pressure. Checking 1 Open the fuel tank filler cap and check for a partial vacuum in the tank. If this is the case.Volvo Trucks North America Date Group No. With the fuel tank cap removed. 2 DANGER Remove the fuel tank cap before blowing air into the vent line to prevent air pressure from building up in the fuel tank. 3 Check for water or contaminants in the fuel tank. Failure to do so may result in the fuel tank rupturing or exploding.2006 230 94 12(26) D Fuel Tank. replace the hose and/or vent valve. you will not hear air entering the tank. 4 If any corrective action was taken. Note: If the hose is plugged or the valve is not working properly. Drain or clean as necessary. which may result in serious personal injury or death. Page Service Bulletin 5. . Note: Nipple 9808029 is supplied with hose assembly 9998494. 9998494. Note: When using pressure gauge 9998496.Volvo Trucks North America Date Group No. The calibration and battery test can be carried out using the oscilloscope on the PC according to the instructions in the PC or by using a multimeter. 9998494 T2019291 2 Type 2 Fuel Filter Housing (manual priming pump): • Clean area around the plug on the fuel filter housing (below fuel pressure sensor) and remove the plug. Special tools: 9998339. • Connect nipple and fuel hose 9998494 to the housing. • Connect nipple and fuel hose 9998494 to the housing.2006 230 94 13(26) D Fuel Supply Pressure. 9998496 Other special equipment: J39200 Install test equipment on the engine 1 Type 1 Fuel Filter Housing (electric priming pump): • Clean area around the drain nipple on the fuel filter housing and remove the nipple. Page Service Bulletin 5. 9998494 T2021366 . Checking (Filtered Side) A fault indication (fault code) for low supply pressure must be followed up by checking the supply pressure using an external pressure sensor to rule out any defects in the pressure sensor. see the instructions supplied with the pressure gauge. the pressure sensor must be calibrated and the pressure gauge battery must be checked. Note: Nipple 9808029 is supplied with hose assembly 9998494. 5 psi) at idle • 300 kPa (44 psi) at 1400 rpm . W2005416 Alternative 2. pressure sensor 9998496 and multimeter J39200 4 Start the engine.2006 230 94 14(26) D 3 W2005415 Alternative 1. 5 Check that the supply pressure is at least: • 100 kPa (14. pressure gauge 9998339 Connect measuring equipment using either alternative as illustrated.Volvo Trucks North America Date Group No. Page Service Bulletin 5. Test drive or dyno test and check fuel pressure at full engine load. proceed to “Fuel Supply Pressure. DANGER If a vehicle is driven while test equipment is connected. Page Service Bulletin 5. Checking (Unfiltered Side)” page 16 .Volvo Trucks North America Date Group No. Failure to do so may cause a collision.2006 230 94 15(26) D 6 DANGER When operating the vehicle on streets and highways while a test is being performed. secure all equipment to prevent it from interfering with any functions of the vehicle or the driver. it is mandatory to have one person drive while another performs the test. Failure to do so may cause a collision. which can result in serious injury or death. Minimum pressure at full load should be: • 300 kPa (44 psi) 7 If fuel pressure is below minimum value. which can result in serious injury or death. 9990124. 9998494.Volvo Trucks North America Date Group No. Connect gauge 9998339 or transducer 9998496 and multimeter J39200 to hose. Always ensure that the area around the fan is clear before starting the engine. J39200 T2019406 Type 1 Fuel Filter Housing (electric priming pump) 2 DANGER Do not work close to the fan when the engine is running. Install to filter housing. The engine cooling fan can start at any time without warning. 9998494 1 Remove the screw from the filter inlet line on the fuel filter housing.2006 230 94 16(26) D Fuel Supply Pressure. Connect hose nipple and fuel hose 9998494 to test fitting 9990124. Anything or anybody in the vicinity of the fan when it starts may be seriously damaged or injured.5 psi) at idle • 300 kPa (44 psi) at 1400 rpm T2021365 Type 2 Fuel Filter Housing (manual priming pump) . Start the engine and check the supply pressure at idle and again at full load. Checking (Unfiltered Side) Checks are carried out to ensure that the fuel filter is not blocked. Special tools: 9990124. Minimum supply pressure should be: • 100 kPa (14. Page Service Bulletin 5. 9998496. 5 If any corrective action was taken. it must be replaced/serviced prior to this check in order to eliminate it as a possible cause of low fuel pressure.2006 230 94 17(26) D 3 If fuel pressure is above minimum value before the filter but lower than minimum value after the filter. etc. check: • Fuel quality (water.Volvo Trucks North America Date Group No. • Valve body in the supply pump. If the condition of the prefilter is unknown. see “Valves. this check will be influenced by the condition of the prefilter. the filter is blocked and should be replaced. 4 If the fuel filter is blocked. Clean the fuel tank if necessary. contaminants. perform a test drive. Checking” page 25. Fuel Supply Pump. continue fault tracing. . If fuel pressure is below minimum value. Note: If the vehicle is equipped with a water separator/prefilter.). Page Service Bulletin 5. 2 Check that the overflow valve ball is in contact with the ball seat. 976282 B. 4 Valve Opening Pressure Check WARNING Always wear appropriate eye protection to prevent the risk of eye injury due to contact with debris or fluids. Install overflow valve in opposite side of fitting. Also. the pressure in the fuel system will bleed off and engine start may be delayed. replace the valve. 9998494 5 Check that the reduction valve is unscrewed on the regulator/gauge 9990123 and that the shut-off valve is open. 976282. 9808029. or does not make a good seal with the seat. If no fault is found. Checking Special tools: 949513. 9990123. proceed to the next step. If the ball does not return to the seat. Page Service Bulletin 5. Install bushing 949513 with copper washer to fitting 976282.2006 230 94 18(26) D Overflow Valve. This can be checked by pressing a blunt tool on the ball to check the spring tension. The spring tension should push the ball back securely on the ball seat. W2004415 3 Press the ball inward and release. W2004424 A. 9990123 D. 949513 C. 9998494 1 Remove the overflow valve.Volvo Trucks North America Date Group No. 9808029 E. . when the engine is shut down. Note: If the overflow valve ball is not held fully against the seat by the spring. the pressure in the fuel system will be below specifications. Install nipple 9808029 to bushing. 2006 230 94 19(26) D 6 Connect shop air and test hose 9998494 to regulator/gauge (with gauge set to 0).6 – 4.2 bar (52 – 61 psi) Note: The ball and seat in the overflow valve does not form a complete seal. the supply pressure may be too high. the supply pressure will be too low. Opening pressure should be: • 3. Replace the overflow valve. recheck for any change in supply pressure. Page Service Bulletin 5. therefore a small amount of leakage is acceptable. it is unlikely that the overflow valve is the cause of the low supply pressure. page 18. 9 If the overflow valve is opened at pressure above 6 bar (87 psi). 7 Increase air pressure with the reduction valve. as shown in illustration. Connect test hose to nipple. 10 If any corrective action was taken. . The valve must remain closed under the specified pressure. Note: If the opening pressure of the overflow valve is higher than specification. 8 If the overflow valve is opened at a pressure below 3. Note the pressure reading on the gauge when the overflow valve opens. Continue troubleshooting the other components in the fuel system. The purpose of this test is to W2004413 check overflow valve opening pressure. Replace the overflow valve.Volvo Trucks North America Date Group No.6 bar (52 psi). 9990150. 9990150 .2006 230 94 20(26) D Fuel Restriction. 9990124 W2004302 3 Attach vacuum gauge 9990150 to hose 9998494. Checking Special tools: 9990124. Attach tool 9990124 to fuel hose and fuel cooling plate. Page Service Bulletin 5. 9998494 1 Remove lower banjo bolt on EECU fuel cooling plate. 9998494. W2004304 2 Install hose nipple and fuel hose 9998494 to tool 9990124.Volvo Trucks North America Date Group No. Hg). For best results. The engine cooling fan can start at any time without warning. Vacuum pressure should not exceed –35 kPa (–10 in. Anything or anybody in the vicinity of the fan when it starts may be seriously damaged or injured. check should be made with engine under full load (test drive or dyno test). 5 If vacuum pressure is greater than –35 kPa (–10 in. Check: • Secondary fuel filter • Water separator/prefilter • Fuel suction lines • Splitter valve • Fuel filter housing (remove fuel bowl and inspect) • Fuel tank pick up tube(s) . Hg). residual fuel pressure is forced back towards the supply side. Once engine is shut down.2006 230 94 21(26) D 4 DANGER Do not work close to the fan when the engine is running. Page Service Bulletin 5. there is too much fuel restriction which will result in low fuel pressure.Volvo Trucks North America Date Group No. Run engine at rated engine speed. Note: Disconnect gauge 9990150 from hose 9998494 before engine is shut down to avoid possible damage to gauge. Always ensure that the area around the fan is clear before starting the engine. The positive pressure may force the gauge out of its normal range which could result in gauge damage. Connect transparent hose 9990056 and insert the other end of the hose into a suitable container.2006 230 94 22(26) D Air in Fuel System. refer to Service Information.Volvo Trucks North America Date Group No. To avoid injury. Note: To get a accurate indication of the amount of air exiting the test hose. Checking Note: For a more detailed mechanical check for locating air entry into the fuel system. keep hands and fingers away from the fan while the engine is running. Very small bubbles in this area are normal and are hard to judge as seen through the clear hose. 9990149 1 Air in fuel check (return connection) Remove the return hose at the front of the cylinder head. Hands and/or fingers in the path of the fan blades can be injured or severed. W2004303 . with the engine running. DANGER Cooling fan may engage without warning. group 23. T2019057 2 Air in fuel check (supply connection) Remove the fuel supply line between fuel filter housing and EECU fuel cooling plate. the technician should watch for air bubbles in the area where the test hose enters the fuel level in the container. Special tools: 9990056. Page Service Bulletin 5. 2006 230 94 23(26) D 3 Install test hose 9990149 to check for air on the supply (suction) side of the fuel system. Page Service Bulletin 5. Flying objects could cause eye injury. Hands and/or fingers in the path of the fan blades can be injured or severed.” group 2309 . “Locating Air Entry into the Fuel System6” Note: It is normal to see a small amount of air in the return line. W2004301 4 Using the priming pump. To avoid injury. Note: Run engine long enough to purge any remaining air that may have entered the fuel system when the test hose was being installed. 5 IMPACT or ID DVD: Info type “Diagnostics. 5 DANGER Cooling fan may engage without warning. keep hands and fingers away from the fan while the engine is running. Start the engine and check whether the hoses contain air when the engine is running. 6 If the fuel system contains air or exhaust gases on the pressure (return) side.” group 2103 6 IMPACT or ID DVD: Info type “Repair. Checklist G.Volvo Trucks North America Date Group No. refer to Service Information. “Fault Tracing. test to determine whether the fuel contains carbon monoxide. purge all air from the fuel system. WARNING Safety glasses should be worn when working around a turning fan blade. Low Compression5 ” Also refer to Service Information. Page Service Bulletin 5. Check: • Fuel lines • Fuel line fittings (thread connections) • Fuel line fittings (seals) • Rubber seals on fuel priming pump (are they damaged?) • O-ring seal on fuel bowl (on fuel filter housing) • High restriction on the supply (suction) side Note: With the Type 1 (With Electric Fuel Priming Pump). .Volvo Trucks North America Date Group No.2006 230 94 24(26) D 7 If the fuel system contains air on the supply (suction) side. in some cases it may be necessary to inspect the seals on the fuel priming pump. even if no air is seen in the test hose (if engine cannot run under full load). Perform appropriate measures to eliminate further possible contamination.2006 230 94 25(26) D Water Separator and Pre-filter. T2019292 A Safety valve B Non-return valve for bleeding the fuel system 2 Replace the valve body. further inspection is required. . drain excess water and/or contaminants from the fuel tank and clean tanks if necessary. Valves. Page Service Bulletin 5. it must be inspected and cleaned thoroughly to prevent contamination from undetected dirt or debris. Checking Special tools: J29925 1 Check the water separator/pre-filter for any contaminants that may have plugged the filter(s). J29925 3 If excessive contamination was found. 2 If the water separator/pre-filter was prematurely plugged. 3 Remove and check the non-return valve (B) in the same way as the safety valve. 1 Remove the safety valve plug (A) on the fuel pump and remove the valve body and spring. Checking Note: Before removing the supply pump.Volvo Trucks North America Date Group No. Note: Before cleaning the valve seats in the supply pump with compressed air: All fuel lines must be removed from the supply pump to avoid air being forced into the fuel system. Cut open the filter(s) using tool J29925 and determine the type of contamination. if necessary. or if the filter was plugged. Fuel Supply Pump. Check the sealing surface of the valve body for damage and debris. W2005418 A Location of the overflow hole B Bolt (M8) . 1 CAUTION If a new fuel pump is installed and used with a worn accessory drive.Volvo Trucks North America Date Group No. Replace the supply pump if damaged. This would result in no fuel pressure. 4 Check to see whether the overflow hole (A) between the seals in the supply pump housing is leaking engine oil or fuel. Inspect the accessory drive for wear. recheck for any change in supply pressure. Checking Note: If any previous corrective action was taken. Leaks from the overflow hole indicate that the seals in the supply pump drive device are worn. Replace the fuel pump if leaks are evident. 2 Remove the fuel pump. Fuel Supply Pump. fuel pump may be damaged prematurely. 3 Check the valve seats in the supply pump. Check the supply pump shaft/gears for evidence of wear or damage (including excessive end play). Note: Traces of oil underneath the pump may come from the M8 bolt (B) in the timing gear plate.2006 230 94 26(26) D 4 Replace the valve body and spring. 5 If any corrective action was taken. Replace the supply pump if damaged. or damage which could cause the fuel pump drive shaft to be incorrectly driven by the accessory drive. recheck for any change in supply pressure before removing the supply pump. it is possible that the fuel pump drive shaft could separate from the drive slot. Check for damage to the valve body contact surfaces. Replace the bolt or seal the thread using sealant. Page Service Bulletin 5. excessive end-play. if necessary. If the accessory drive is excessively worn.