GM Service Manual Online
For 1990-2009 cars only

Water Pump Replacement L18

Removal Procedure


    Object Number: 751427  Size: SH
  1. Drain the cooling system. Refer to Cooling System Draining and Filling .
  2. Remove the drive belt. Refer to Drive Belt Replacement for the 8.1L engine.
  3. Remove the fan clutch. Refer to Fan Clutch Replacement .
  4. Reposition the outlet hose clamp at the water pump.
  5. Remove the outlet hose from the water pump.

  6. Object Number: 470692  Size: SH
  7. Reposition the bypass hose clamps at the water pump and water crossover.
  8. Remove the bypass hose.

  9. Object Number: 470790  Size: SH
  10. Remove the water pump bolts.
  11. Remove the water pump.
  12. Remove and discard the water pump gaskets.

Installation Procedure


    Object Number: 470790  Size: SH
  1. Place NEW water pump gaskets into place.
  2. Notice: Refer to Fastener Notice in the Preface section.

  3. Install the water pump.
  4. Install the water pump bolts.
  5. Tighten
    Tighten the water pump bolts to 50 N·m (37 lb ft).


    Object Number: 470692  Size: SH
  6. Install the bypass hose.
  7. Position the bypass hose clamps at the water pump and water crossover.

  8. Object Number: 751427  Size: SH
  9. Install the outlet hose to the water pump.
  10. Position the outlet hose clamp at the water pump.
  11. Install the fan clutch. Refer to Fan Clutch Replacement .
  12. Install the drive belt. Refer to Drive Belt Replacement for the 8.1L engine.
  13. Fill the cooling system. Refer to Cooling System Draining and Filling .

Water Pump Replacement Caterpillar

Refer to the Caterpillar® Service Manual.

Water Pump Replacement 6.6L

Removal Procedure

  1. Remove the thermostat housing crossover. Refer to Thermostat Housing Crossover Replacement .
  2. Remove the thermostat bypass pipe. Refer to Thermostat Bypass Pipes Replacement .
  3. Remove the crankshaft balancer. Refer to Crankshaft Balancer Replacement for the 6.6L (LLY) engine.

  4. Object Number: 1336115  Size: SH
  5. Remove the water pump to engine coolant pipe nuts.
  6. Remove the engine wiring harness retainer from the inner stud.

  7. Object Number: 1336116  Size: SH
  8. Remove the water pump bolts. Note the location of the bolts. The bolts are three different lengths.
  9. Remove the water pump.
  10. Remove and discard the water pump O-ring and coolant pipe gasket.
  11. If required, clean and inspect the water pump. Refer to Water Pump Cleaning and Inspection for the 6.6L (LLY) engine.

Installation Procedure


    Object Number: 1336116  Size: SH
  1. Lubricate the water pump O-ring with engine oil.
  2. Install the engine coolant pipe gasket and water pump O-ring.
  3. Notice: Refer to Fastener Notice in the Preface section.

  4. Install the water pump.
  5. Install the water pump bolts. Ensure the correct length bolt is used in the proper location.
  6. Tighten
    Tighten the bolts to 21 N·m (15 lb ft).

  7. Install the engine wiring harness retainer on the water pump outlet pipe inner stud.

  8. Object Number: 1336115  Size: SH
  9. Install the water pump to engine coolant pipe nuts.
  10. Tighten
    Tighten the nuts to 21 N·m (1 lb ft).

  11. Install the thermostat bypass pipe. Refer to Thermostat Bypass Pipes Replacement .
  12. Install the thermostat housing crossover. Refer to Thermostat Housing Crossover Replacement .
  13. Install the crankshaft balancer. Refer to Crankshaft Balancer Replacement for the 6.6L (LLY) engine.

Water Pump Replacement 7.8L

Removal Procedure

  1. Drain the coolant. Refer to Cooling System Draining and Filling .
  2. Remove the drive belt from the water pump pulley. Refer to Drive Belt Replacement .
  3. Remove the fan clutch and adapter. Refer to Fan Clutch Replacement .
  4. Remove the following components from the water pump:
  5. • The clamp
    • The heater hose

    Object Number: 228206  Size: SH
  6. Remove the bolts from the water duct.
  7. Remove the following components:
  8. • The water duct
    • The O-ring

    Object Number: 228210  Size: SH
  9. Remove the water pump bolts.
  10. Remove the following components:
  11. • The water pump
    • The gaskets
  12. Clean the following components:
  13. • The surface of the water pump
    • The surface of the engine block
    • The bolt threads
    • The water duct sealing surfaces
  14. Inspect the following components for wear, deterioration or corrosion.
  15. Replace the components as necessary:

    • The clamps
    • The hoses
    • The water pump

Installation Procedure


    Object Number: 228210  Size: SH
  1. Install new gaskets to the water pump.
  2. Install the water pump to the engine block.
  3. Notice: Refer to Fastener Notice in the Preface section.

  4. Install the water pump bolts.
  5. Tighten
    Tighten the water pump bolts to 19 N·m (14 lb ft).


    Object Number: 228206  Size: SH
  6. Lube the O-ring with soap suds.
  7. Install the following components:
  8. • The water duct
    • The O-ring
  9. Install the water duct bolts.
  10. Tighten

    1. Tighten the M8 bolt to 19 N·m (14 lb ft).
    2. Tighten the M16 bolt to 125 N·m (92 lb ft).
  11. Install the following components to the water pump:
  12. • The heater hose
    • The clamp

    Tighten
    Tighten the clamp to 5 N·m (44 lb in).


    Object Number: 228234  Size: SH
  13. Install the adapter (2) to the pump.
  14. Tighten
    Tighten the adapter bolts to 68 N·m (50 lb ft).

  15. Install the fan clutch. Refer to Fan Clutch Replacement .
  16. Install the drive belt. Refer to Drive Belt Replacement .
  17. Fill the cooling system. Refer to Cooling System Draining and Filling .
  18. Inspect the system for leaks.