DD 15 – Section 35.4 Fuel Injectors

Section 35.4
Fuel Injectors

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 1. Black Seal Installed‪

 3. Copper Washer‪

 2. Green Seal Installed‪

The injectors are installed with a injector clamp and bolt in the cylinder head and are located between the valves of the respective cylinder.‪

Section 35.4.1
Removal of the Injector

Remove as follows:‪

  1. Steam clean the engine.
  2. Disconnect the batteries to prevent failure of the MCM.
  3. Remove the rocker cover.

    To avoid injury from flying debris when using compressed air, wear adequate eye protection (face shield or safety goggles) and do not exceed 40 psi (276 kPa) air pressure.‪

  4. Disconnect the electrical contacts from the injectors.
  5. Remove harness with solenoids attached.
  6. Disconnect 14–pin injector harness connector.
  7. Remove appropriate injector wiring harness. Remove spring clip holding the appropriate injector harness connector to camshaft frame.


    To prevent the escape of high pressure fuel that can penetrate skin, ensure the engine has been shut down for a minimum of 10 minutes before servicing any component within the high pressure circuit. Residual high fuel pressure may be present within the circuit.‪

  8. Disconnect appropriate high pressure line at the camshaft frame and fuel rail. Using fuel line tool J–48770.
  9. Remove appropriate injector hold down bolt and clamp.
  10. Lift the clamp and injector from its seat in the cylinder head using J-47391 injector removal tool.
  11. Remove clamps from injectors and install a tip protector onto the injector nozzle.
  12. Cover the injector hole to keep out foreign material.


    Avoid cleaning (wire brushing etc.) the injector tip spray holes to prevent damage and plugging.‪

  13. Carefully remove carbon material from the injector exterior in the area where the tip joins the nut, using a clean rag soaked with clean diesel fuel.


    Injector O-ring seals, injector clamp bolt and the injector copper washer are considered one-use items and cannot be reused. Any time an injector is removed, the injector bolt, three injector O-ring seals and copper washer must be replaced with new parts. Failure to replace the O-ring seals copper washer and bolt can result in leakage.‪

  14. Inspect the injector body for visible damage. Replace the injector if damaged.
  15. Remove and discard the three injector O-rings and the copper washer.

Section 35.4.2
Installation of the Injector

Install as follows:‪

Note: Ensure fuel is removed from cylinder head.

  1. If the fuel system is contaminated:
    1. Drain the fuel tanks and refill with clean fuel.
    2. Clean the fuel water/separator and replace the fuel filter module filters with new filters.
  2. If the coolant system is contaminated with fuel, flush and reverse flush the system.
  3. If the oil system is contaminated, change the engine oil and filters.


    Leftover fuel must be removed from the injector bore before injector installation.‪


    The injector tube bore should be cleaned and inspected for damage before installation of the injector.‪

  4. Check to make sure the injector tube bore is thoroughly clean.
  5. Remove injector nozzle tip protector.


    The copper washer must be installed with recess facing injector body. Incorrect installation can cause combustion gasses to enter the fuel system.‪

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     1. Recess side of copper washer‪

     2. Top side of copper washer‪

  6. Install a new copper washer with lip facing down onto the injector.
  7. Apply a thin coat of acid free grease or clean engine oil to the injector seal rings and install them in the injector nut ring grooves. Make sure they are properly seated.
  8. Install the injector and clamp as an assembly into its respective injector bore. Align the clamp over the bolt hole, install the new bolt into injector clamp and snug then release injector bolt.

    Note: If the high pressure lines leak after installation the lines need to be replaced.

  9. Install high pressure line to the injectors; finger tighten the cap nuts.
  10. Torque the injector clamp bolts to 20 N·m (15 lb·ft) + 90°.

    Note: If the isolators were removed from the fuel rail ensure they are installed in the position from which they were removed.

  11. Using tool J–48770 torque the high pressure lines to the injector to 40 N·m (29 lb·ft).
  12. Install electrical contacts to injector and tighten to 1.5 Nm (1 ft/lb).
  13. Finger tighten all screws before final torque is applied.
  14. Install injector harness and tighten the allen head mounting screws to 10 Nm (7 ft/lb)
  15. Install solenoids and harness together with new O-rings.
  16. Install spring clip holding injector harness connector to camshaft frame.
  17. Connect 14-pin injector harness connector.
  18. Record the injector calibration code from the name plate with the proper cylinder location and enter calibration codes using DDDL service routine.
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  19. Install rocker cover and torque bolts in a cross pattern to 20 Nm (15 ft/lb).
  20. Connect batteries.

DD15 Fuel System Technician's Guide - DDC-SVC-MAN-0037
Generated on 10-13-2008

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