CAUTION  Clean all fittings before disassembly. Dirt or contaminants can damage the fuel system.

With the keyswitch ON and the engine cranking, check the high pressure injection pump.

Check the high pressure injection pump fuel flow as follows:

• Disconnect the high pressure fuel line to the fuel rail from the high pressure injection pump.
• Connect a clear hose to the outlet of the high pressure injection pump.
• Run the high pressure fuel line into an empty bucket.
• Crank the engine for 30 seconds and measure the fuel pump flow.

  Minimum fuel pump flow is 75 ml [2.5 oz] in 30 seconds at 125 rpm or 90 ml [3.04 oz] in 30 seconds at 150 rpm for 4-cylinder and 6-cylinder engines.

  If the minimum fuel flow is achieved, the electronic fuel control (EFC) actuator is defective. Refer to Procedure 005-007 in the ISB ^e, ISB and QSB (Common Rail Fuel System) Series Engines Service Manual, Bulletin 4021271.

  If the minimum fuel flow is not achieved, the high-pressure injection pump is defective and needs to be replaced.

If the engine can be started, a measurement of the fuel return flow can diagnose a high-pressure fuel pump problem. The following steps describe how to test the high-pressure fuel pump return flow.

WARNING  The fuel pump high-pressure fuel lines and fuel rail contain very high-pressure fuel. Never loosen any fittings while the engine is running. Personal injury and property damage can result.

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 measured at idle conditions. The fuel system leakage test in the INSITE™ electronic service tool can be used to increase system pressure and therefore increase the ability to detect high leakage.

Disconnect the fuel pump return line.

3.9L and 5.9L Engines

Attach the fuel pressure gauge adapter, Part Number 3164044, to the fuel pump return fitting. Install a quick-disconnect block-off fitting, Part Number 3164583, on the disconnected drain line.

4.5L and 6.7L Engines

Attach the female quick-disconnect fuel drain hose, Part Number 4918434, onto the fuel pump drain connection. Install a quick-disconnect block-off fitting, Part Number 4918464, on the disconnected drain line.

Follow the fuel return line from the fuel pump to the fuel return manifold. At the fuel return manifold, remove the banjo bolt for fuel pump return line and install test fitting, Part Number 3164618.

CAUTION  If tool Part Number 3164618 is installed at the fuel pump, it will block return flow and cause possible damage to the fuel pump. Install tool Part Number 3164618 only at the fuel return manifold.

For automotive and industrial applications, the return manifold is located near the top of the engine, beside the fuel rail.

For marine engines, the return manifold is located on the side of the engine block, next to the ECM.

WARNING  Fuel can be returned at highly elevated temperatures. Wear safety glasses and protective gloves and clothing when performing this test. Avoid contact with returned fuel.

Place the end of the fuel pressure gauge adapter tool or fuel drain hose into a 500 ml graduated beaker, Part Number 3823705.

Start the engine.

Measure the flow rate by recording the amount of time necessary to fill a 400 ml graduated beaker. Flow Specification: Standard Idle Conditions (750 rpm) 4- and 6-cylinder 400 ml (maximum) in 25 seconds

WARNING  Batteries can emit explosive gases. To reduce the possibility of personal injury, always ventilate the compartment before servicing the batteries. To reduce the possibility of arcing, remove the negative (-) battery cable first and attach the negative (-) battery cable last.

Disconnect the batteries.

WARNING  Fuel is flammable. Keep all cigarettes, flames, pilot lights, arcing equipment, and switches out of the work area and areas sharing ventilation to reduce the possibility of severe personal injury or death when working on the fuel system.

CAUTION  Do not vent the fuel system on a hot engine; this can cause fuel to spill onto a hot exhaust manifold, which can cause a fire.

CAUTION  Drain the fuel-water separator into a container, and dispose of the contents in accordance with local environmental regulations.

CAUTION  Clean all fittings before disassembly. Dirt or contaminants can damage the fuel system.

Disconnect and remove the low-pressure fuel supply and drain lines. Refer to Procedures 006-024 and 006-013.

For engines with a low mount fuel filter, the fuel filter head must be removed to remove the fuel pump. Refer to Procedure 006-017.

WARNING  Batteries can emit explosive gases. To reduce the possibility of personal injury, always ventilate the compartment before servicing the batteries. To reduce the possibility of arcing, remove the negative (-) battery cable first and attach the negative (-) battery cable last.

WARNING  Fuel is flammable. Keep all cigarettes, flames, pilot lights, arcing equipment, and switches out of the work area and areas sharing ventilation to reduce the possibility of severe personal injury or death when working on the fuel system.

WARNING  Do not vent the fuel system on a hot engine; this can cause fuel to spill onto a hot exhaust manifold, which can cause a fire.

CAUTION  Use caution when draining the fuel system , so that fuel is not spilled or drained into the bilge area. The fuel must be disposed of in accordance with local environmental regulations.

• Remove the low-pressure fuel supply lines. Refer to Procedure 006-024.
• Remove the low-pressure fuel drain lines. Refer to Procedure 006-013.
• Apply a counter-torque to the fitting on the high-pressure pump to reduce the possibility of a leak or a loose fitting. Remove the high-pressure supply line from the fuel pump to the fuel rail (flared connection).
• Disconnect the fuel control actuator electrical connector.
• Remove the dipstick mounting capscrew and position the dipstick out of the way for pump removal.
• Remove the valve cover lubrication vent flex hose connector at the engine block mounted adapter. Refer to Procedure 003-002.
• Remove the belt guard section located in front of the sea water pump. Refer to Procedure 008-001.

NOTE: A counter-torque must be applied to the fitting on the high pressure pump. This is to prevent the fitting from being loosened and to prevent the possibility of a leak.

Disconnect the high-pressure supply line from high-pressure fuel pump to the fuel rail and loosen the holding brackets.

Disconnect the EFC Actuator Valve wire harness connector.

Remove the three flanged fuel pump mounting nuts.

Remove the fuel pump from the gear housing.

Remove the fuel pump drive access cover with a 3/8-inch drive ratchet.

CAUTION  Place a clean cloth in the air-gap between the fuel pump drive gear and the gear cover, or use a screwdriver to prevent the mounting nut and lock washer from being dropped into the front gear train.

CAUTION  The fuel pump drive gear is captive between the gear housing and the gear cover. Do not rotate the engine while the gear is not supported by the fuel pump drive shaft. The gear, gear housing or gear cover can be damaged.

Remove the fuel pump drive gear retaining nut and lock washer.

CAUTION  Protect the fuel pump drive shaft threads from damage during gear removal.

Install the fuel pump drive gear puller onto the drive shaft and gear.

Hold the gear puller while removing the fuel pump drive gear.

Remove the fuel pump assembly.

Remove the three fuel pump flanged mounting nuts.

Remove the fuel pump drive access cover with a 3/8-inch drive ratchet.

CAUTION  Place a clean cloth in the air gap between the fuel pump drive gear and the gear cover, or use a screw driver to prevent the mounting nut and lockwasher from being dropped into the front gear train.

CAUTION  The fuel pump drive gear is captive between the gear housing and the gear cover. Do not rotate the crankshaft while the gear is not supported by the fuel pump drive shaft. The gear, gear housing or gear cover can be damaged.

Remove the fuel pump drive gear retaining nut and lockwasher.

Install the spacer, Part Number 4918317, from service tool, Part Number 3163381, onto the fuel pump drive shaft.

CAUTION  Protect the fuel pump drive shaft threads from damage while removing the fuel pump gear.

Install the fuel pump drive gear puller, Part Number 3163381, onto the fuel pump drive shaft and gear.

Use a ratchet and remove the fuel pump drive gear from the fuel pump drive shaft.

Remove the spacer, Part Number 4918317, from the fuel pump drive shaft.

Remove the fuel pump assembly.

WARNING  The fuel pump high-pressure fuel lines and fuel rail contain very high-pressure fuel. Never loosen any fittings while the engine is running. Personal injury and property damage can result.

CAUTION  Be sure that the fuel inlet and return valves are returned to the open position before cranking the engine. Engine damage can result if the valves are in the wrong position when the engine is cranked or started. Environmental damage can also occur.

CAUTION  Use caution when disconnecting or removing fuel lines, replacing filters and priming the fuel system, so that fuel is not spilled or drained. The fuel and fuel filters must be discarded in accordance with local environmental regulations.

Refer to Procedure 005-999 in Familiarization section for further information.

Allow the lift pump to run by turning the key switch ON and waiting 30 seconds before starting.

NOTE: It is not necessary to vent air from the high-pressure fuel system before starting the engine. Cranking the engine will prime the fuel system.

Operate the engine and check for leaks.

Dry Fuel Filter and Fuel Tubes: this condition occurs if the engine has come from the manufacturing plant without being tested before shipping, if the fuel filters have been changed. Before starting the engine, pump the hand priming pump 120 times.

Full Fuel Filter and Fuel Tubes: This condition occurs if the engine is being installed for the first time after being built, but was tested at the manufacturing plant or is being reinstalled. Before starting the engine, pump the hand priming pump 40 times.

NOTE: NOTE: It is not necessary to vent air from the high-pressure fuel system before starting the engine. Cranking the engine will prime the fuel system.

Operate the engine and check for leaks.

WARNING  Fuel is flammable. Keep all cigarettes, flames, pilot lights, arcing equipment, and switches out of the work area and areas sharing ventilation to reduce the possibility of severe personal injury or death when working on the fuel system.

CAUTION  Use caution when disconnecting or removing fuel lines, replacing filters and priming the fuel system, so that fuel is not spilled or drained into the bilge area. Do not drop or throw filter elements into the bilge area. The fuel and fuel filters must be discarded in accordance with local environmental regulations.

CAUTION  Failure to properly prime the fuel system on marine engines can result in damage to the fuel cooler. Be sure the drain valve(s) are open. Be sure a good flow of fuel is present through the fuel cooler by cycling the keyswitch at least five times before starting the engine.

NOTE: It is not necessary to vent air from the high-pressure fuel system before starting the engine. Cranking the engine will prime the engine.

The fuel transfer pump is initiated by turning the keyswitch to the ON position. The pump will run for 50 to 60 seconds, then shut off. Priming the fuel system requires cycling the keyswitch several (5 or more) times to make sure the fuel filter is primed properly and that all the air is out of the fuel system, down stream through the fuel cooler.