Water Pump Replacement Gasoline

1. Drain the coolant from the radiator. Refer to Cooling System Draining and Filling .
2. Remove the upper fan shroud. Refer to Fan Shroud Replacement .
3. Remove the drive belt. Refer to Drive Belt Replacement or Drive Belt Replacement in Engine Mechanical.
4. Remove the fan, the fan clutch, and the pulley from the coolant pump. Refer to Fan Clutch Replacement .
5. Disconnect the radiator outlet hose from the coolant pump. Refer to Radiator Hose Replacement .
6. Disconnect the heater hose from the coolant pump. Refer to Heater Hoses Replacement in Heating, Ventilation, and Air Conditioning.



7. Disconnect the bypass hose.



8. Remove the water pump bolts.
9. Remove the coolant pump from the engine block.
10. Clean the mating surfaces on the coolant pump and the engine block.

1. Install the new gaskets and the water pump.
2. Apply GM P/N 12346004 or equivalent thread sealant on the water pump mounting bolts.




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 bolts.

Tighten
Tighten the bolts to 41 N·m (30 lb ft).




4. Connect the bypass hose.
5. Connect the heater hose to the coolant pump. Refer to Heater Hoses Replacement in Heating, Ventilation, and Air Conditioning.
6. Connect the radiator outlet hose to the coolant pump. Refer to Radiator Hose Replacement .
7. Install the coolant pump pulley, the fan, and fan clutch to the coolant pump hub. Refer to Fan Clutch Replacement .
8. Install the drive belt. Drive Belt Replacement or Drive Belt Replacement in Engine Mechanical.
9. Install the upper fan shroud. Refer to Fan Shroud Replacement .
10. Start the engine. Run the engine, with the radiator cap removed, until the upper radiator hose becomes hot (This indicates that the thermostat is open).
11. While the engine is running at idle speed, add coolant to the radiator, until the level reaches the bottom of the filler neck. Refer to Cooling System Draining and Filling .



12. Install the radiator cap. Make sure that the cap arrows line up with the overflow tube.
13. Inspect the cooling system for leaks.

Water Pump Replacement Diesel

1. Drain the coolant from the radiator. Refer to Cooling System Draining and Filling .
2. Remove the fan shroud. Refer to Fan Shroud Replacement .
3. Remove the drive belt. Refer to Drive Belt Replacement in Engine Mechanical.
4. Remove the fan and fan clutch. Refer to Fan Clutch Replacement .
5. Raise the vehicle. Support the vehicle with safety stands. Refer to Lifting and Jacking the Vehicle in General Information.
6. Remove the following vacuum pump components. Refer to Vacuum Pump Replacement in Engine Mechanical 6.5L:

6.1.	The mounting bracket nuts

6.2.	The bolt securing the vacuum pump bracket and the generator

6.3.	The vacuum pump and the bracket

7. Remove the power steering pump. Do not disconnect the hoses. Lay the pump aside. Refer to Power Steering Pump Replacement .
8. Lower the vehicle.
9. Disconnect the lower radiator hose from the coolant pump. Refer to Radiator Hose Replacement .
10. Disconnect the bypass hose from the coolant pump.
11. Remove the bolts, the studs, the coolant pump backing plate and the coolant pump.



12. Remove the bolt from the rear of the coolant pump backing plate.
13. Remove the coolant pump and the gasket from the backing plate.

Important: All of the flanges must be free of oil.

14. Clean the following mating surfaces:

•	The coolant pump

•	The coolant pump backing plate (both sides)

•	The engine block

1. Install the gasket.
2. Install the water pump to the water pump backing plate.
3. Apply high temperature thread adhesive GM P/N 12345493, or equivalent, to the bolt threads.

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.

4. Install the bolts.

Tighten
Tighten the bolt to 28 N·m (20 lb ft).




5. Apply anaerobic sealer GM P/N 1052942, or equivalent to the water pump backing plate. The sealer must be wet to the touch when the bolts are installed and tightened.



6. Install the coolant pump and the coolant pump backing plate to the engine.
7. Install the bolts and the studs.

Tighten

•	Tighten the water pump to front cover bolts to 42 N·m (31 lb ft).

•	Tighten the water pump plate to front cover bolts to 28 N·m (20 lb ft).

8. Connect the bypass hose.
9. Connect the lower radiator hose. Refer to Radiator Hose Replacement .
10. Install the power steering bracket and the pump. Refer to Power Steering Pump Replacement .
11. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
12. Install the vacuum pump and the bracket. Refer to Vacuum Pump Replacement in Engine Mechanical 6.5L:
13. Lower the vehicle.
14. Install the fan and fan clutch assembly and the coolant pump pulley. Refer to Fan Clutch Replacement .
15. Install the drive belt. Refer to Drive Belt Replacement in Engine Mechanical.
16. Install the fan shroud. Refer to Fan Shroud Replacement .
17. Fill the surge tank with coolant. Refer to Cooling System Draining and Filling .
18. Start the engine. Run the engine with the surge tank cap removed, until the upper radiator hose becomes hot. (This indicates that the thermostat is open).
19. While the engine is running at idle speed, add coolant to the surge tank until the level reaches the FULL mark. Refer to Cooling System Draining and Filling .



20. Install the surge tank cap. Make sure the cap arrows line up with the overflow tube.
21. Inspect the cooling system for leaks.