GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Isuzu 🢒 2001 🢒 Isuzu T-Series (Truck Line C) 🢒 Engine 🢒 Engine Controls - 7.8L 🢒 Fuel Injection Pump Replacement

Removal Procedure
  1. Tilt the cab. Refer to Cab Tilting in General Information.

    2. Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

  2. Disconnect the negative battery cable.
  3. Disconnect the pressure control valve (PCV) harness connector.
  4. Disconnect the pump position CMP sensor harness connector.
  5. Remove the clamp bolts from the fuel supply line, fuel return line and the supply line to the fuel filter.
  6. Remove the fuel supply line.
  7. Remove the fuel return line.
  8. Remove and discard the oil supply line.
  9. Remove the oil return line.
  10. Remove the two fuel supply lines between the supply pump and the common rail.

    11. Object Number: 734304 Size: SH
  11. Disconnect the coupling fixing bolts.

    12. Object Number: 736148 Size: SH
  12. Remove the fuel supply pump fixing bolts.
  13. Remove the fuel supply pump assembly.

Installation Procedure
  1. Turn the crankshaft to align number 1 cylinder top dead center (TDC) mark to pointer.
  2. Turn the coupling of the supply pump to align the timing mark on the supply pump and the pointer on the air compressor body.

    3. Object Number: 736148 Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  3. Install the supply pump assembly onto the pump bracket.

    4. Tighten
    Tighten the supply pump fixing bolts to 25 N·m (18 lb ft).


    Object Number: 734304 Size: SH
  4. Install the coupling bolts.

    5. Tighten
    Tighten the coupling bolts to the following:

    • Bolt 1: 91 N·m (66 lb ft)
    • Bolt 2: 61 N·m (46 lb ft)
    • Bolt 1: 60 N·m (45 lb ft)
  5. Install the two fuel supply lines between the supply pump and the common rail.
  6. Install the oil return line.
  7. Install a new oil supply line.
  8. Install the fuel return line.

    9. Important: When installing the fuel supply line on the fuel feed pump, you must use a special gasket between the supply line eye, on the relief valve, and the return line eye, short return line. If you use any other gasket, the engine will not start.

  9. Install the fuel feed line.

    10. Tighten
    Tighten the clamp bolts to 6 N·m (52 lb in).

  10. Connect the pump position CMP sensor harness connector.
  11. Connect the negative battery cables.
  12. Lower the cab.