GM Service Manual Online
For 1990-2009 cars only

Water Pump Replacement LNF

Special Tools

J 43651 Water Pump Holding Tool

Removal Procedure

  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
  2. Remove the right engine splash shield. refer to Engine Splash Shield Replacement - Right Side.

  3. Object Number: 2105283  Size: SH
  4. Remove the bolts (1) retaining the water pump access plate (2) and remove the plate from the front cover (3). Discard the seal.
  5. Drain the coolant from the water pump using the plug at the bottom of the pump. Refer to Cooling System Draining and Filling.
  6. Remove the thermostat housing. Refer to Engine Coolant Thermostat Housing Replacement.

  7. Object Number: 1769795  Size: SH
  8. Remove the radiator outlet pipe from the rear of the water pump and the thermostat housing by gently twisting.

  9. Object Number: 2105286  Size: SH

    Note: The water pump holding tool supports the sprocket and chain during water pump service. The tool must be used or the balance shaft will have to be re-timed.

  10. Install the J 43651 (1) into position.
  11. Tighten the bolts on the water pump holding tool (2) into the threads on the water pump sprocket.
  12. Install the access cover bolts that were removed earlier to secure the water pump holding tool to the front cover assembly.
  13. Remove the three inner water pump sprocket to water pump bolts.

  14. Object Number: 951420  Size: SH

    Note: Be sure to remove both front water pump bolts from the front of the engine block.

  15. Remove the two front water pump bolts.

  16. Object Number: 1578334  Size: SH
  17. Remove the two rear water pump bolts.

  18. Object Number: 951638  Size: SH
  19. Remove the water pump.
  20. Remove and discard the water pump O-ring seal.

Installation Procedure


    Object Number: 951802  Size: SH

    Note: Prior to installing the water pump, read the entire procedure. This will help avoid balance shaft chain re-timing and ensure proper sealing.

  1. Install a NEW water pump O-ring seal.
  2. Note: A guide pin can be created to aid in water pump alignment. Use a M 6 m x 6 mm stud. Thread the pin into the water pump sprocket.

  3. Using the guide pin, align the pin with the water pump holding tool.
  4. Position the water pump against the engine block and hand tighten the front and rear water pump bolts.
  5. Caution: Refer to Fastener Caution in the Preface section.

  6. Install the inner water pump sprocket bolts. After two bolts are snug, remove the guide pin and install the 3rd bolt.
  7. • Tighten the front and rear water pump bolts to 25 N·m (18 lb ft).
    • Tighten the water pump sprocket bolts to 10 N·m (89 lb in).

    Object Number: 2105286  Size: SH
  8. Remove the J 43651 (1).

  9. Object Number: 896331  Size: SH
  10. Install the water pump access plate and bolts, with a NEW seal and tighten the bolts to 10 N·m (89 lb in).

  11. Object Number: 1769795  Size: SH
  12. Install the radiator outlet pipe to the rear of the water pump and the thermostat housing using new O rings.
  13. Install the thermostat housing. Refer to Engine Coolant Thermostat Housing Replacement.
  14. Install the right engine splash shield. refer to Engine Splash Shield Replacement - Right Side.
  15. Lower the vehicle.
  16. Refill the coolant system to specifications and inspect for leaks. Refer to Cooling System Draining and Filling.