ISC, ISCe, QSC8.3, ISL, ISLe3, ISLe4 and QSL9 Engines – 006-026   Injector

WARNING  The fuel pump, high-pressure fuel lines, and fuel rail contain very high-pressure fuel. Do not loosen any fittings while the engine is running. Wait at least 10 minutes after shutting down the engine before loosening any fittings in the high-pressure fuel system to allow pressure to decrease to a lower level.

CAUTION  Use caution when disconnecting or removing fuel lines, replacing filters and priming the fuel system 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  Installation of the banjo flow adapter at any place other than the fuel drain manifold can cause damage to high pressure fuel system components.

Return fuel is routed from the injectors, the fuel rail pressure relief valve, and the fuel pump head through three different drain lines.

Measurement of fuel injector leakage requires the use of a fuel return hose, Part Number 3164618.

The tool is used to isolate the leakage from just the injectors, so it can be measured with a graduated cylinder.

If necessary, this tool can be constructed using the steps outlined below.

To make a banjo bolt flow adapter tool, drill and tap the hex face of a M12 x 1.5 banjo bolt, Part Number 3903035, or equivalent.

Drill and tap the hex face of the banjo bolt to the size of a male union (or other hose fitting) being used (example 1/8-inch NPT hose barb).

Drill and tap the open end of the banjo bolt for the installation of a 5/16-24 set screw.

WARNING  Depending on the circumstance, diesel fuel is flammable. When inspecting or performing service or repairs on the fuel system, to reduce the possibility of fire and resulting severe personal injury, death or property damage, never smoke or allow sparks or flames (such as pilot lights, electrical switches, or welding equipment) in the work area.

CAUTION  Use caution when disconnecting or removing fuel lines, replacing filters and priming the fuel system 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.

Remove the M12 banjo bolt that connects the fuel injector drain line to the fuel drain manifold.

Install the M12 fuel return hose, Part Number 3164618, at the fuel drain manifold.

Route the fuel return hose into a collection device.

Obtain a graduated cylinder that is marked in cubic centimeters; example: graduated beaker, Part Number 3823705, or equivalent. A kitchen style measurement cup that is marked in cubic centimeters (cc’s) also works well.

Start the engine and allow the engine to idle until drain fuel from the injector drain line begins to flow into the collection container.

Connect INSITE™ electronic service tool.

If the engine will not start, these procedures are still valid; however, the pass/fail specification is different.

If the engine will not start, drain flow must be measured while engaging the starter for 30 seconds at a time.

If the injector leakage is excessive during cranking and the engine will not start, check the following:

• High pressure fuel connector installation. Refer to Procedure 006-052 in Section 6.
• High pressure fuel connector damage. Refer to Procedure 006-052 in Section 6.
• Use the fuel leak test tool, Part Number 3164325, to isolate injectors from the fuel rail, one at a time.

CAUTION  Fuel is at high pressure during this test. After connecting the test fitting, close the engine cover and stand clear of high-pressure fuel lines.

If the engine will start, the following steps will determine if the injector drain flow is excessive.

While the engine is operating at idle, use INSITE™ electronic service tool High Pressure Leak Test to create high fuel rail pressure. INSITE™ electronic service tool will command 1500 BAR [21,756 psi] fuel rail pressure while the engine is at idle during this test.

Record the amount of time it takes for 300 cc [10.1 oz] of fuel to flow from the injector drain line when performing the INSITE™ electronic service tool High Pressure Leak Test.

If 300 cc [10.1 oz] of fuel leaks from the injectors in less than 45 seconds, there is at least one loose or damaged high pressure fuel connector and/or injector.

NOTE: Fuel temperature and fuel type will influence this measurement. For example; as the engine is warmed up and the injectors become hot, the leakage rate will increase. Also, low viscosity fuels, such as kerosene, will cause the leakage rate to increase. The above specification is correct for on-highway diesel fuels where fuel inlet temperature is less than 49°C [120°F].

After recording the fuel leakage rate, stop INSITE™ electronic service tool High Pressure Leak Test and turn the keyswitch to OFF.

If injector drain flow is excessive, it will be necessary to isolate the injector(s) or fuel connector(s) that are damaged or worn.

A loose fuel connector retaining nut results in a poor seal at the interface between the fuel connector and the injector. This loose condition will result in a leak of high-pressure fuel to the injector drain.

Verify first that the fuel connectors are properly tightened. Refer to Procedure 006-052 in Section 6.

If loose retaining nut(s) are found, test for leakage after tightening the retaining nut(s).

CAUTION  Do not install the isolation tool at the high pressure pump outlet fitting. Severe engine damage will result. This tool must only be installed at the fuel rail for the purpose of isolating the high-pressure fuel supply from individual injectors.

CAUTION  Make certain the keyswitch is in the OFF position (engine not running) when loosening or tightening high-pressure fuel lines.

Use leak test isolation tool, Part Number 3164325, to isolate excessive fuel drainage from injectors or fuel connectors.

Isolate the injector and fuel connector for each cylinder by installing the isolation tool at the fuel rail in place of the high-pressure fuel line that supplies the fuel connector.

Record the amount of time it takes for 300 cc [10.1 oz] of fuel to flow from the injector drain line while the engine is running. Use INSITE™ electronic service tool High Pressure Leak Test. Do this up to six (6) times, once while each line is isolated.

If isolating a single injector and high-pressure fuel connector causes the leakage time to increase significantly compared to the rest of the set, that injector and fuel connector must be inspected.

Inspect the suspect fuel connector. Refer to Procedure 006-052 in Section 6. If the fuel connector is not damaged, replace both the injector and the fuel connector.

Remove the M12 diagnostic flow adapter from the fuel drain manifold and install the M12 banjo. Refer to Procedure 006-013 in Section 6.

Install all high-pressure fuel lines. Refer to Procedure 006-051 in Section 6.

Operate the engine and check for leaks.

CAUTION  Attempting to remove the injector without first removing the fuel connector will cause damage to the injector body and/or fuel connector.

• Remove the rocker lever cover. Refer to Procedure 003-011 in Section 3.
• Remove the engine brake, if equipped. Refer to Procedure 020-004 in Section 20.
• Remove the fuel connector. Refer to Procedure 006-052 in Section 6.

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.

CAUTION  Use caution when disconnecting or removing fuel lines, replacing filters and priming the fuel system 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  Attempting to remove the injector without first removing the fuel connector will cause damage to the injector body and/or fuel connector.

NOTE: All fuel system diagnostics procedures and component specifications have been moved. Refer to Procedure 005-236 in Section 5.

• Disconnect the batteries. Refer to Procedure 013-009 in Section 13.
• Remove the rocker lever cover. Refer to Procedure 003-011 in Section 3.
• Remove the high-pressure fuel line. Refer to Procedure 006-051 in Section 6.
• Remove the engine brake, if equipped. Refer to Procedure 020-004 in Section 20.
• Remove the fuel connector. Refer to Procedure 006-052 in Section 6.
• Remove the exhaust rocker lever assembly. Refer to Procedure 003-008 in Section 3.

Remove the injector hold-down clamp capscrew that is nearest the exhaust manifold side of the engine.

Remove the injector hold-down clamp.

Remove the high-pressure fuel connector. Refer to Procedure 006-051 in Section 6.

Use the injector puller, Part Number 3825156, to pull the injector out of the head.

Alternatively, a rocker cover capscrew can be installed into the top of the injector and used to pull the injector from the cylinder head.

Be sure the injector seal washer is removed from the injector bore.

Disconnect the injector wire harness from the injector.

Remove the two injector hold-down clamp capscrews and remove the injector hold-down clamp.

Use a small heel-bar to pry up on the injector clamp hold-down flange (part of the injector body just above the cylinder head casting).

WARNING  While testing the injectors, keep hands and body parts away from the injector nozzle. Fuel coming from the injector is under extreme pressure and can cause serious injury by penetrating the skin.

Install the injectors on an injector test stand. Open the bypass valve for the pressure gauge, so the spray pattern can be checked.

Use injector test fixture, Part Number 3162269, with the injector nozzle test, Part Number 3376946.

Operate the test stand lever quickly several times to check the spray pattern of the injectors. Verify that the correct number of plumes are present for the number of holes in the injector. Also pay close attention to the size and shape of each plume. If possible, compare the spray pattern to that of a new injector with the same assembly number.

NOTE: The injector spray pattern is an excellent indicator of the nozzle hole condition. Check each plume carefully. It is possible that only a single hole has been damaged, resulting in degraded engine performance.

Close the bypass valve for the pressure gauge and operate the test stand lever to check the nozzle opening pressure. There must be a good crisp “pop” when the nozzle opens and the pressure must be within the specification for the assembly number.

The injector will pop between 275 bar [3,989 psi] and 300 bar [4,351 psi].

If the nozzle opening pressure is excessively low and/or the nozzle sprays excessive fuel, the injector needle can be sticking. The needle can be stuck due to poor lubrication or debris.

Sometimes it is possible to unstick an injector needle by using the injector test stand. Open the bypass valve for the pressure gauge and operate the test stand lever rapidly for 10 to 20 strokes.

Recheck the nozzle opening pressure and spray pattern to see if the injector has returned to normal operation.

If the injector is still out of specification, replace the injector.

Check the injector for drip and/or excessive leak down. Close the bypass valve for the pressure gauge and build pressure to within 10 bars [145 psi]of the opening pressure of the nozzle.

A drop of fuel must not form within 15 seconds.

Place the injector in the injector clamp and remove the nozzle retaining nut.

NOTE: Injectors covered under warranty by the manufacturer must not be repaired. See the manufacturer’s warranty instructions.

Remove the nozzle, intermediate plate, spring, and shims from the injector.

WARNING  When using solvents, acids, or alkaline materials for cleaning, follow the manufacturer’s recommendations for use. Wear goggles and protective clothing to avoid personal injury.

WARNING  Some solvents are flammable and toxic. Read the manufacturer’s instructions before using.

CAUTION  Do not use a steel wire brush or glass beading to clean the injectors. This will damage the nozzle holes and cause performance problems.

Clean the injector tip and body with safety solvent and a soft, clean, cloth.

Clean the injector internal components with clean diesel fuel and a clean cloth. Make sure there is no debris in the internal parts of the injector.

Install shims, as necessary, to modify the nozzle opening pressure. More shims raise the nozzle opening pressure, less shims lower the nozzle opening pressure.

Install the spring, button, intermediate plate, and nozzle/needle.

Make sure the intermediate plate is in the correct orientation with the supply hole on the plate lining up with the supply hole on the holder.

Install the retaining nut finger tight. Place the injector in the injector clamp and tighten the retaining nut. Install the sealing washer and body o-ring.

NOTE: If a new injector is being installed, a new fuel connector must be used

Make sure the injector bore is clean and that only one (1) sealing washer is installed on the injector nozzle.

Lubricate the injector o-ring with clean engine oil.

Place the injector in the head in the proper orientation.

Place the injector hold-down clamp on top of the injector and make sure the injector is fully seated in the injector bore.

Install the injector hold-down clamp and tighten.

Make sure the injector bore is clean and that only one (1) sealing washer is installed on the injector nozzle.

Lubricate the injector o-ring with clean engine oil.

Place the injector in the cylinder head in the proper orientation (fuel inlet toward the high-pressure fuel connector).

Use the injector shipping sleeve to make sure the injector is seated in the injector bore.

NOTE: If a new injector is being installed, a new fuel connector must be used.

Start the injector hold-down clamp capscrews, and tighten hand-tight.

Install the high-pressure fuel connector, making sure the end of the high-pressure fuel connector is in the injector inlet port.

NOTE: The high-pressure fuel connector should click into place if it is seated in the injector inlet port correctly.

Start the high-pressure fuel connector retaining nut and tighten partially.

NOTE: This is not the final torque for the high-pressure fuel connector retaining nut.

Tighten the injector hold-down clamp capscrews.

NOTE: Make sure to tighten the hold-down clamp capscrews evenly. Check to make sure the gap between the hold-down clamp and the injector is equally spaced around the injector body.

CAUTION  Do not overtighten the injector harness. The injector terminals will be damaged if excessive over-torqued.

Install the injector wiring harness to the injector.

NOTE: Orient the injector wires so they will not interfere with a rocker lever or engine brake housing. If the rocker lever is able to come into contact with the injector harness, it will rub through the wire insulation and cause injector circuit fault codes.

NOTE: Polarity of the wiring is not significant. The signal and return wires can be connected to either injector terminal.

• Install the fuel connector. Refer to Procedure 006-052 in Section 6.
• Install the rocker lever cover. Refer to Procedure 003-011 in Section 3.
• Install the high pressure fuel lines. Refer to Procedure 006-051 in Section 6.
• Operate the engine and check for leaks.

• Install the exhaust rocker lever assembly. Refer to Procedure 003-008 in Section 3.
• Install the engine brake, if equipped. Refer to Procedure 020-004 in Section 20.
• Install the high pressure fuel lines. Refer to Procedure 006-051 in Section 6.
• Install the rocker lever cover. Refer to Procedure 003-011 in Section 3.
• Open the fuel supply and return valves. Refer to the OEM service manual.
• Connect the batteries. Refer to Procedure 013-009 in Section 13.
• Operate the engine and check for leaks.