Water Pump Replacement LE5

Tools Required

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.




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.

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




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

8. Remove the 2 water pump bolts.



9. Remove the rear 2 water pump bolts.



10. Remove the engine wiring harness clip nut from the water pump stud.
11. Remove the engine wiring harness clip from the stud.
12. Remove the water pump.

1. Apply sealant GM P/N 12378521 (Canadian P/N 88901148) or equivalent to the water pump drain plug.

Notice: Refer to Fastener Notice in the Preface section.

2. Install the water pump drain plug.

Tighten
Tighten the drain plug to 20 N·m (15 lb ft).





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

3. Using the J 25025-5 , or a guide pin align the pin with the water pump holding tool.
4. Position the water pump against the engine block and hand tighten the water pump bolts.
5. Install the inner water pump sprocket bolts. After 2 are snug, remove the guide pin and install the 3rd bolt.

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

6. Tighten the water pump sprocket bolts last.

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




7. Remove the J 43651 .
8. Install the coolant heater. Refer to Coolant Heater Replacement .



9. Install the water pump access plate and bolts.

Tighten
Tighten the bolts to 10 N·m (89 lb in).

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

Water Pump Replacement LZ4/LZ9

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. Remove the water pump bolts.
6. Remove the water pump and gasket.
7. Clean the water pump mating surfaces.

Notice: Refer to Fastener Notice in the Preface section.




1. Position a NEW water pump gasket and the water pump to the engine front cover.
2. Install the water pump bolts.

Tighten
Tighten the bolts to 25 N·m (18 lb ft).




3. Install the water pump pulley and bolts.
4. Install the drive belt. Refer to Drive Belt Replacement.
5. Tighten the water pump pulley bolts.

Tighten
Tighten the bolts to 25 N·m (18 lb ft).

6. Fill the cooling system. Refer to Cooling System Draining and Filling.
7. Inspect for leaks.