GM Service Manual Online
For 1990-2009 cars only

Water Pump Replacement LP1, LY7

Tools Required

EN 46104 Water Pump Pulley Holding Tool

Removal Procedure

  1. Drain the cooling system. Refer to Cooling System Draining and Filling .
  2. Remove the generator and water pump drive belt. Refer to Water Pump and Generator Belt Replacement for the 2.8L (LP1) engine, or Water Pump and Generator Belt Replacement for the 3.6L (LY7) engine.

  3. Object Number: 1342893  Size: SH
  4. Use the EN 46104 (1) in order to retain the water pump pulley.

  5. Object Number: 902876  Size: SH
  6. Remove the water pump pulley bolts.
  7. Remove the water pump pulley.

  8. Object Number: 946142  Size: SH
  9. Remove the water pump bolts.
  10. Remove the water pump.
  11. Remove and DISCARD the water pump seal.
  12. Carefully clean the water pump sealing surfaces.

Installation Procedure


    Object Number: 946142  Size: SH
  1. Install a NEW water pump seal.
  2. Install the water pump.
  3. Notice: Refer to Fastener Notice in the Preface section.

  4. Install the water pump bolts.
  5. Tighten
    Tighten the water pump bolts to 10 N·m (89 lb in).


    Object Number: 902876  Size: SH
  6. Install the water pump pulley and the water pump pulley bolts.

  7. Object Number: 1342893  Size: SH
  8. Use the EN 46104 (1) in order to retain the water pump pulley.
  9. Install the water pump pulley bolts.
  10. Tighten
    Tighten the water pump pulley bolts to 12 N·m (106 lb in).

  11. Install the generator and water pump drive belt. Refer to Water Pump and Generator Belt Replacement for the 2.8L (LP1) engine, or Water Pump and Generator Belt Replacement for the 3.6L (LY7) engine.
  12. Fill the cooling system. Refer to Cooling System Draining and Filling .

Water Pump Replacement LS2

Removal Procedure


    Object Number: 179301  Size: SH
  1. Remove the air cleaner outlet duct. Refer to Air Cleaner Outlet Duct Replacement .
  2. Drain the cooling system. Refer to Cooling System Draining and Filling .
  3. Remove the cooling fan assembly. Refer to Engine Cooling Fan Replacement .
  4. Remove the accessory drive belt. Refer to Drive Belt Replacement - Accessory .
  5. Reposition the inlet and outlet hose clamps at the water pump.
  6. Remove the inlet and outlet hoses from the water pump.

  7. Object Number: 185256  Size: SH
  8. Reposition the heater inlet and surge tank outlet hose clamps at the water pump.
  9. Remove the heater inlet and surge tank outlet hoses from the water pump.

  10. Object Number: 550333  Size: SH
  11. Remove the water pump bolts.

  12. Object Number: 309751  Size: SH
  13. Remove the water pump.
  14. Remove the water pump gaskets.
  15. Clean and inspect the water pump. Refer to Water Pump Cleaning and Inspection .

Installation Procedure


    Object Number: 550334  Size: SH
  1. Install the water pump and gaskets to the engine block.

  2. Object Number: 550333  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 water pump bolts.
  4. Tighten

    1. Tighten the water pump bolts a first pass to 15 N·m (11 lb ft).
    2. Tighten the water pump bolts a final pass to 30 N·m (22 lb ft).

    Object Number: 185256  Size: SH
  5. Install the heater inlet and surge tank outlet hoses to the water pump.
  6. Position the heater inlet and surge tank outlet hose clamps at the water pump.

  7. Object Number: 179301  Size: SH
  8. Install the inlet and outlet hoses to the water pump.
  9. Position the inlet and outlet hose clamps at the water pump.
  10. Install the accessory drive belt. Refer to Drive Belt Replacement - Accessory .
  11. Install the cooling fan assembly. Refer to Engine Cooling Fan Replacement .
  12. Fill the cooling system. Refer to Cooling System Draining and Filling .
  13. Install the air cleaner outlet duct. Refer to Air Cleaner Outlet Duct Replacement .