GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1999 🢒 GMC C-Series Medium Duty Truck B7 🢒 Engine 🢒 Engine Controls - 7.4L 🢒 Fuel Pump Replacement

Removal Procedure

    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.

  1. Remove the negative battery cable.
  2. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .
  3. Remove the fuel feed and return pipe quick-connect fittings at fuel sender assembly. Refer to Metal Collar Quick Connect Fitting Service and Plastic Collar Quick Connect Fitting Service .

    4. Object Number: 318483 Size: SH
  4. Remove the fuel sender assembly electrical connector (7).
  5. Lower the fuel tank if necessary to allow clearance for removal of fuel sender assembly. Refer to Fuel Tank Replacement - Left Side and Fuel Tank Replacement - Right Side .
  6. Remove the six nuts and washers (1) retaining the fuel sender assembly lock ring (8).
  7. Remove the lock ring, the sender assembly (2), and the seal.
  8. Remove the fuel pump electrical connector.
  9. Remove the fuel pump strainer from the bottom of the fuel pump.
  10. Rotate the strainer in one direction and pull the strainer off the pump. Discard the strainer after inspection.
  11. Remove the fuel pump (4) from the sender assembly (2).
    12. 11.1. Pull the fuel pump up into the attaching hose while pulling outward from the bottom support.
    11.2. Do not damage the rubber insulator or the strainer.
  12. Inspect the fuel pump attaching hose for signs of deterioration.
  13. Inspect the rubber sound insulation at the bottom of the pump.

Installation Procedure

    Object Number: 318483 Size: SH
  1. Install the fuel pump assembly (4) into the attaching hose.
  2. Install the fuel pump strainer.
  3. Install the fuel pump electrical connector.

    4. Important: Care should be taken not to fold over or twist the strainer (3), when installing the sender assembly as this will restrict fuel flow.

  4. Install the new seal, sender assembly (2), and lock ring (8).

    5. Make sure the lock ring alignment holes fit over the tabs on the tank.

  5. Install the six washers and nuts (1) retaining the fuel sender assembly lock ring.
  6. Install the fuel tank if necessary. Refer to Fuel Tank Replacement - Left Side and Fuel Tank Replacement - Right Side .

    7. Slide the tank into the original position

  7. Install the fuel feed and return pipe quick-connect fittings. Refer to Metal Collar Quick Connect Fitting Service and Plastic Collar Quick Connect Fitting Service .
  8. Install the fuel sender assembly electrical connector (7).
  9. Install the negative battery cable.
  10. Check for fuel leaks using the following procedure:
    11. 10.1. Turn the ignition switch to ON position for 2 seconds.
    10.2. Turn the ignition switch to OFF for 10 seconds.
    10.3. Turn the ignition switch to ON position.
    10.4. Check for fuel leaks.