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For 1990-2009 cars only

Water Pump Replacement LZ9

Removal Procedure


    Object Number: 1557687  Size: SH
  1. Drain the cooling system. Refer to Cooling System Draining and Filling.
  2. Loosen the water pump pulley bolts.
  3. Remove the drive belt. Refer to Drive Belt Replacement.
  4. Remove the water pump pulley bolts and pulley.

  5. Object Number: 1557689  Size: SH
  6. Remove the water pump bolts.
  7. Remove the water pump and gasket.
  8. Clean the water pump mating surfaces.

Installation Procedure

    Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1557689  Size: SH
  1. Position a NEW water pump gasket and the water pump to the engine front cover.
  2. Install the water pump bolts.
  3. Tighten
    Tighten the bolts to 25 N·m (18 lb ft).


    Object Number: 1557687  Size: SH
  4. Install the water pump pulley and bolts.
  5. Install the drive belt. Refer to Drive Belt Replacement.
  6. Tighten the water pump pulley bolts.
  7. Tighten
    Tighten the bolts to 25 N·m (18 lb ft).

  8. Fill the cooling system. Refer to Cooling System Draining and Filling.
  9. Inspect for leaks.

Water Pump Replacement L61

Tools Required

    • J 25025-5 Dial Indicator Mounting Post
    • J 43651 Water Pump Holding Tool

Removal Procedure


    Object Number: 896331  Size: SH
  1. Remove the thermostat housing. Refer to Engine Coolant Thermostat Housing Replacement .
  2. Remove the coolant heater. Refer to Coolant Heater Replacement .
  3. Remove the water pump access plate from the front cover.

  4. Object Number: 789912  Size: SH

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

  5. Install the J 43651 into position.
  6. Tighten the bolts on the water pump holding tool into the threads on the water pump sprocket.
  7. Install the access cover bolts that were removed earlier to secure the water pump holding tool to the front cover assembly.
  8. Remove the 3 inner water pump sprocket to water pump bolts through the holes in the water pump holding tool.

  9. Object Number: 951420  Size: SH

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

  10. Remove the 2 water pump bolts.

  11. Object Number: 1578334  Size: SH
  12. Remove the rear 2 water pump bolts.

  13. Object Number: 951638  Size: SH
  14. Remove the engine wiring harness clip nut from the water pump stud.
  15. Remove the engine wring harness clip from the stud.
  16. Remove the water pump.

Installation Procedure


    Object Number: 964352  Size: SH
  1. Apply sealant GM P/N 12378521 (Canadian P/N 88901148) or equivalent to the water pump drain plug.
  2. Notice: Refer to Fastener Notice in the Preface section.

  3. Install the water pump drain plug.
  4. Tighten
    Tighten the drain plug to 20 N·m (15 lb ft).


    Object Number: 951802  Size: SH

    Important: A guide pin can be created to aid in water pump alignment. Use a M6 m x 6 mm stud.

  5. Using the J 25025-5 or a guide pin, align the pin with the water pump holding tool.
  6. Position the water pump against the engine block and hand tighten the water pump bolts.
  7. Install the inner water pump sprocket bolts. After 2 are snug, remove the guide pin and install the 3rd bolt.
  8. Tighten
    Tighten the bolts to 25 N·m (18 lb ft).

  9. Tighten the water pump sprocket bolts last.
  10. Tighten
    Tighten the bolts to 10 N·m (89 lb in).


    Object Number: 789912  Size: SH
  11. Remove the J 43651 .
  12. Install the coolant heater. Refer to Coolant Heater Replacement .

  13. Object Number: 896331  Size: SH
  14. Install the water pump access plate and bolts.
  15. Tighten
    Tighten the bolts to 10 N·m (89 lb in).

  16. Install the thermostat housing. Refer to Engine Coolant Thermostat Housing Replacement .

Water Pump Replacement LZ4

Removal Procedure


    Object Number: 1557687  Size: SH
  1. Drain the cooling system. Refer to Cooling System Draining and Filling.
  2. Loosen the water pump pulley bolts.
  3. Remove the drive belt. Refer to Drive Belt Replacement.
  4. Remove the water pump pulley bolts and pulley.

  5. Object Number: 1557689  Size: SH
  6. Remove the water pump bolts.
  7. Remove the water pump and gasket.
  8. Clean the water pump mating surfaces.

Installation Procedure


    Object Number: 1557689  Size: SH
  1. Position a NEW water pump gasket and the water pump to the engine front cover.
  2. Notice: Refer to Fastener Notice in the Preface section.

  3. Install the water pump bolts.
  4. Tighten
    Tighten the bolts to 25 N·m (18 lb ft).


    Object Number: 1557687  Size: SH
  5. Install the water pump pulley and bolts.
  6. Install the drive belt. Refer to Drive Belt Replacement.
  7. Tighten the water pump pulley bolts.
  8. Tighten
    Tighten the bolts to 25 N·m (18 lb ft).

  9. Fill the cooling system. Refer to Cooling System Draining and Filling.
  10. Inspect for leaks.