If the engine will not start, disconnect the high-pressure fuel outlet line from the high-pressure injection pump.
Refer to Procedure 006-071 in Section 6.
Disconnect the fuel pump actuator connector.
Insert a piece of tubing over the outlet fitting of the fuel pump and route it into a 500 ml [17 oz] graduated beaker,
Part Number 3823705.
Crank the engine and measure the amount of fuel exiting the fuel pump.
NOTE: Do not crank the engine for 30 seconds continuously. Crank the engine in 10 second intervals with a 30 second break between cranking. This reduces the possibility of overheating the starter motor.
Minimum flow: Engine Cranking (150 rpm) 70 ml [2.4 oz] in 30 seconds.
If the high-pressure injection pump does not meet the flow specifications, check for air in the fuel. Refer to Procedure
006-003 in Section 6. Check for inlet restriction. Refer to Procedure 006-020 in Section 6. Check the fuel filter.
Refer to Procedure 006-015 in Section 6.
If these checks are acceptable, replace the fuel pump actuator. Use the following procedure in the Troubleshooting and Repair Manual, CM2150 Electronic Control System, ISB, ISC, ISL, ISLe, ISDe, and QSB3.3 Engines, Bulletin 4021570. Refer to Procedure 019-117 in Section 19.
After replacing the fuel pump actuator, measure the fuel pump flow again. If the flow is not within specification,
replace the fuel pump.
Connect the fuel pump actuator electrical connection.
Clear all faults with an electronic service tool.
If the engine can be started , measurement of the fuel return can diagnose a high-pressure fuel pu mp problem .
The following steps describe how to test the high-pressure fuel pump return flow.
NOTE: Make certain that the eng ine is at operating temperatures before runni ng this test.
Prior to collecting the flow data, let the engine run for 1 minute after the test lines are installed .
A malfunctioning fuel return overflow valve or fuel pump can result in high return from the fuel pump . The return
fuel flow from the pump must be measu red at idle conditions.
The fuel system leakage test in IN SITE”‘ electronic service tool can be used to increase system pressure and therefore increase the ability to detect high leakage.
Front Gear Train
NOTE: This test setup is only for checking gear pump drain flow. Additional troubleshooting will be performed to
collect rail and/or injector drain flow. Refer to Procedure 006-026 in Section 6. The injector procedure will describe
the test set up to separate the rai l, injector, and gear pump drain flows at the same time.
Follow the fuel drain line from the fu el pump to the left side of the fu el filter head.
Remove the quick disconnect line from the filter head.
Install the quick disconnect lines, kit Part Number 4918354, onto the filter head and fuel pump drain line.
Route the high-pressure injection pump drain hose, Part Number, 4918433 , male connector, into a graduated beaker, Part Number 3823705.
Route the fuel filter head drain hose, Part Number 4918434, female connector, into a bucket.
Rear Gear Train
NOTE: This test setup is only for checking gear pump drain flow. Use the following procedure if additional
troubleshooting will be performed to collect rail and/or injector drain flow. Refer to Procedure 006-026 in Section
6. The injector procedure will describe the test setup to separate the rail, injector, and gear pump drain flows at
the same time.
Disconnect the OEM fuel drain line from the high-pressure injection pump drain connection.
Disassemble and remove the banjo bolt and eyelet from the drain connection.
Install the fuel drain hose, Part Number 3164618, into the eyelet at the end of the rail and injector drain line, and cap
off with Part Number 4918297 (part of kit Part Number 4918295).
Route the drain hose into a bucket.
This is the injector and high-pressure relief valve drain flow.
Install the drain flow hose, Part Number 4918679 (1 ), or 4948296 (2), into the threaded drain connection located
on the pump.
Route the fuel drain hose into a graduated beaker, Part Number 3823705.
Start the engine.
Measure the fuel pump drain flow.
Maximum flow at standard idle conditions (750 rpm): 500 ml [17 oz] in 30 seconds.
If the high pressure injection pump does not meet the flow specifications, check for air in the fuel. Refer to Procedure
006-003 in Section 6. Check for inlet restriction. Refer to Procedure 006-020 in Section 6.
If the fuel pump drain flow is not within specification, no air was detected in the fuel, and the inlet restriction is within specification, then the fuel pump is damaged.
Replace the fuel pump.
