GM Service Manual Online
For 1990-2009 cars only

Water Pump Replacement LL8

Tool Required

J 41240 Fan Clutch Remover and Installer

Removal Procedure

  1. Drain the coolant. Refer to Cooling System Draining and Filling .
  2. Remove the fan and shroud. Refer to Cooling Fan and Shroud Replacement .
  3. Remove the drive belt. Refer to Drive Belt Replacement .

  4. Object Number: 748318  Size: SH
  5. Using the J 41240 , secure the water pump pulley and remove the water pump pulley bolts.
  6. Remove the J 41240 .
  7. Remove the water pump pulley.

  8. Object Number: 637645  Size: SH
  9. Loosen and remove the water pump bolts.
  10. Remove the water pump.
  11. Clean and inspect the water pump. Refer to Water Pump Cleaning and Inspection .
  12. Discard and replace the gasket.

Installation Procedure

  1. Install a new water pump gasket.
  2. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 637645  Size: SH
  3. Install the water pump and secure the water pump with the bolts.
  4. Tighten

        • On the initial pass, tighten the bolts to 4 N·m (35 lb in).
        • On the final pass, tighten the bolts to 10 N·m (89 lb in).

    Object Number: 748318  Size: SH
  5. Install the water pump pulley.
  6. Install the water pump pulley bolts.
  7. Using the J 41240 , secure the water pump pulley while tightening the water pump pulley bolts.
  8. Tighten
    Tighten the bolts to 25 N·m (18 lb ft).

  9. Remove the J 41240 .
  10. Install the drive belt. Refer to Drive Belt Replacement .
  11. Install the fan and the shroud. Refer to Cooling Fan and Shroud Replacement .
  12. Fill the cooling system with the specified coolant and concentration. Refer to Cooling System Draining and Filling .
  13. Inspect for leaks.

Water Pump Replacement LM4

Tools Required

J 38185 Hose Clamp Pliers

Removal Procedure


    Object Number: 898123  Size: SH
  1. Drain the cooling system. Refer to Cooling System Draining and Filling .
  2. Loosen the air cleaner outlet duct clamps at the following locations:
  3. • Throttle body
    • Mass air flow (MAF)/intake air temperature (IAT) sensor
  4. Remove the air cleaner outlet duct bolt and duct.
  5. Remove the accessory drive belt tensioner. Refer to Drive Belt Tensioner Replacement - Accessory in Engine Mechanical - 4.8L, 5.3L, and 6.0L.
  6. Remove the cooing fan and shroud. Refer to Cooling Fan and Shroud Replacement .

  7. Object Number: 901490  Size: SH
  8. Using J 38185 , reposition the inlet hose clamp at the water pump.
  9. Remove the inlet hose from the water pump.

  10. Object Number: 901491  Size: SH
  11. Using J 38185 , reposition the outlet hose clamp at the water pump.
  12. Remove the outlet hose from the water pump.

  13. Object Number: 901492  Size: SH
  14. Remove the auxiliary heater inlet and outlet hose/pipe nut.
  15. Using J 38185 , reposition the throttle body hose clamp at the throttle body.
  16. Remove the hose from the throttle body.
  17. Using J 38185 , reposition the auxiliary heater inlet and outlet hose/pipe clamps at the water pump.
  18. Remove the inlet and outlet hoses/pipes from the water pump.

  19. Object Number: 260121  Size: SH
  20. Remove the water pump bolts.
  21. Remove the water pump and gaskets.
  22. Discard the water pump gaskets.

Installation Procedure

Important: All gaskets surfaces are to be free of oil or other foreign material during assembly.

    Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 260121  Size: SH
  1. Install the water pump and NEW gaskets.
  2. Install the water pump bolts.
  3. Tighten

        • On the initial pass, tighten the bolts to 15 N·m (11 lb ft).
        • On the final pass, tighten the bolts to 30 N·m (22 lb ft).

    Object Number: 901492  Size: SH
  4. Install the auxiliary heater inlet and outlet hose/pipe nut.
  5. Tighten
    Tighten the nut to 10 N·m (89 lb in).

  6. Install the hose to the throttle body.
  7. Using J 38185 , position the throttle body hose clamp at the throttle body.
  8. Install the inlet and outlet hoses/pipes to the water pump.
  9. Using J 38185 , position the auxiliary heater inlet and outlet hose/pipe clamps at the water pump.

  10. Object Number: 901491  Size: SH
  11. Install the outlet hose to the water pump.
  12. Using J 38185 , position the outlet hose clamp at the water pump.

  13. Object Number: 901490  Size: SH
  14. Install the inlet hose to the water pump.
  15. Using J 38185 , position the inlet hose clamp at the water pump.
  16. Install the cooing fan and shroud. Refer to Cooling Fan and Shroud Replacement .
  17. Install the accessory drive belt tensioner. Refer to Drive Belt Tensioner Replacement - Accessory in Engine Mechanical - 4.8L, 5.3L, and 6.0L.

  18. Object Number: 898123  Size: SH
  19. Install the air cleaner outlet duct and bolt.
  20. Tighten
    Tighten the bolt to 10 N·m (89 lb in).

  21. Tighten the air cleaner outlet duct clamps at the following locations:
  22. • Throttle body
    • MAF/IAT sensor

    Tighten
    Tighten the clamps to 7 N·m (62 lb in).

  23. Fill the cooling system. Refer to Cooling System Draining and Filling .