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Perform the following procedures for removal and installation of the fuel injector line. The following procedures will also explain how to repair a leaking or broken fuel injector line. ‪

Fuel Injector Line Removal

Remove the fuel injector line as follows: ‪


To avoid injury from fire, keep all potential ignition sources away from diesel fuel, including open flames, sparks, and electrical resistance heating elements. Do not smoke when refueling.


To avoid injury from fire caused by heated diesel-fuel vapors:

  • Keep those people who are not directly involved in servicing away from the engine.
  • Stop the engine immediately if a fuel leak is detected.
  • Do not smoke or allow open flames when working on an operating engine.
  • Wear adequate protective clothing (face shield, insulated gloves and apron, etc.).
  • To prevent a buildup of potentially volatile vapors, keep the engine area well ventilated during operation.
  1. Remove both engine trim covers and identify the leaking line.

    Note: The MBE 4000 engine has individual heads for each cylinder. To remove the injector line from one cylinder, follow these procedures step by step. To remove all the injector lines, repeat each step in these instructions, as applicable, for all six cylinders.

    Note: Remove only leaking lines. Do not attempt to service good lines that are not leaking.

  2. Remove the cylinder head cover for each cylinder head, as required. Refer to section .
  3. Using the injector line torque wrench adaptor (J-45062) , loosen the injector line nuts at the transfer tube and at the injector unit pump. See Figure 42104 .

    1. Injector Line Nut, Unit Pump Fitting ‪

    3. Injector Line Nut, Transfer Tube Fitting ‪

    2. Injector Line ‪

    4. Thrust Bolt ‪

    High-Pressure Injector Line Removal / Installation


    Do not crimp or nick the injector line tubing. Overbending the tubing can close the passage or restrict the flow of fuel. Nicks can cause weak spots that could lead to injector line failure.


    To avoid injury from the sudden release of a high-pressure hose connection, wear a face shield or goggles.

  4. Remove the transfer tube. Use the wrench adaptor (J-45062) to loosen the thrust bolt.

    Note: Discard the failed high-pressure fuel line and transfer tube. Do not re-use them!

Fuel Injector Line Installation

Install the fuel high pressure fuel line and a new transfer tube as follows: ‪


New injector lines are supplied ready for installation. If the flared cone ends of the line do not line up with the transfer-tube and unit-pump fittings, carefully bend the line by hand for a proper fit. Never use pliers or sharp-edged tools to bend injector lines. Doing so could damage them. Injector lines should fit without tension over the transfer-tube and unit-pump fittings.

Note: A torque wrench is designed to a apply a specified torque directly on the fastener. When using a torque wrench with an adaptor, the final torque on the fastener will be greater than the number you set on the wrench itself. The torque values listed below are designed to acommodate any torque variation caused by using the wrench with an adaptor, regardless of the wrench length.

  1. Before installing the injector line, tighten the thrust bolt, using the thrust bolt torque wrench adaptor, (J-45063) . The final torque on the bolt must be 45 Nm (33 lbft ).
  2. Install the injector line nuts finger-tight at both ends.
  3. Using the injector line torque wrench adaptor, (J-45062) , tighten the injector line nuts at the transfer tube and at the unit pump. The final torque on the bolt must be 30 Nm (22 lbft).
  4. Install the cylinder head cover(s), as removed. Refer to section .
  5. Prime the fuel system. Refer to section .


    Diesel engine exhaust and some of its constituents are known to the State of California to cause cancer, birth defects, and other reproductive harm.

    • Always start and operate an engine in a well ventilated area.
    • If operating an engine in an enclosed area, vent the exhaust to the outside.
    • Do not modify or tamper with the exhaust system or emission control system.
  6. Run the engine and check for leaks. Tighten the connections as needed.
  7. Shut down the engine and install the remaining components.