Water Pump Replacement 7.4L

Removal Procedure

Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

1. Disconnect the negative battery cable.
2. Remove the radiator shroud upper section. Refer to Fan Shroud Replacement .
3. Drain the coolant from the system. Refer to Cooling System Draining and Filling .
4. Remove the serpentine drive belt. Refer to Drive Belt Replacement in Engine Mechanical 7.4L.
5. Remove the fan and the pulley from the pump. Refer to Fan Replacement .
6. Remove the lower radiator hose from the pump.



7. Disconnect the coolant bypass hose from the pump.
8. Remove the coolant pump retaining bolts.
9. Remove the coolant pump.
10. Clean the gasket sealing surfaces on the coolant pump and on the engine block.

Installation Procedure

1. Install new gaskets.

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.

2. Install the coolant pump to the engine block.

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

3. Install the bypass hose to the pump.
4. Install the lower radiator hose to the pump.
5. Install the fan and the pulley to the pump. Refer to Fan Replacement .
6. Install the serpentine drive belt. Refer to Drive Belt Replacement in Engine Mechanical 7.4L.
7. Install the radiator shroud upper section. Refer to Fan Shroud Replacement .
8. Fill the cooling system. Refer to Cooling System Draining and Filling .
9. Start the engine. Allow the engine to run with the radiator cap removed until the radiator upper hose is hot and the thermostat is open.
10. While the engine is idling, add coolant to the radiator until the coolant level reaches the bottom of the filler neck.
11. Connect the negative battery cable.

Water Pump Replacement Diesel

Removal Procedure

Notice: Diesel engines are equipped with a high output water pump. This water pump can be identified by the larger nipple for the coolant bypass. The water pump turns in a counter clockwise rotation.

Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

1. Disconnect the negative battery cable.
2. Drain the coolant from the radiator. Refer to Cooling System Draining and Filling .
3. Remove the fan and the pulley. Refer to Fan Replacement .
4. Remove the generator drive belt. Refer to Drive Belt Replacement in Engine Mechanical.
5. Remove the generator and the mounting bracket. Refer to Generator Replacement in Engine Electrical.
6. Remove the power steering pump and lay the pump aside. Refer to Power Steering Pump Replacement in Power Steering System.
7. Remove the accessory engine lift bracket.
8. Disconnect the lower radiator hose from the pump.
9. Disconnect the bypass hose from the pump.



10. Remove the bolts that retain the water pump-to-mounting plate.
11. Remove the studs.
12. Remove the coolant pump plate.
13. Remove the coolant pump.
14. Remove the bolt from the rear of the coolant pump plate.



15. Remove the coolant pump and the gasket from the plate.
16. Ensure that all of the flanges are free from oil. Clean the mating surfaces of the following parts:

•	The coolant pump

•	Both sides of the coolant pump plate

•	The front cover

Installation Procedure

1. Install the gasket.



2. Connect the coolant pump to the coolant pump plate.

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 bolt.

Tighten
Tighten the bolt to 28 N·m (21 lb ft).




4. Connect the water pump and the water pump plate to the front cover.

Apply anaerobic sealer GM P/N 1052357 or an equivalent on the designated points on the plate. The sealer must be wet to the touch when you tighten the bolts.

5. Install the bolts and the studs.

Tighten
Tighten the bolts and the studs to 23 N·m (17 lb ft).

6. Connect the bypass hose and the lower radiator hose.
7. Install the power steering pump and the engine accessory lift bracket. Refer to Power Steering Pump Replacement in Power Steering System.
8. Install the generator and the generator brackets. Refer to Generator Replacement in Engine Electrical.
9. Install the drive belt. Refer to Drive Belt Replacement in Engine Mechanical.
10. Install the fan clutch and the fan pulley assembly. Refer to Fan Replacement .
11. Install the upper radiator shroud. Refer to Fan Shroud Replacement .
12. Install coolant into the radiator. Refer to Cooling System Draining and Filling .
13. Connect the negative battery cable.
14. Start the engine. Operate the engine while the radiator cap is removed until the upper radiator hose is hot and the thermostat is open.
15. Add coolant to the radiator while the engine is running. Add the coolant until the coolant reaches the bottom of the filler neck.
16. Install the radiator cap. Ensure that the arrows line up with the overflow tube.

Water Pump Replacement 5.7L

Removal Procedure

Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

1. Disconnect the negative battery cable.
2. Remove the air cleaner duct.
3. Remove the radiator shroud upper section. Refer to Fan Shroud Replacement .
4. Drain the coolant from the system. Refer to Cooling System Draining and Filling .
5. Remove the drive belt. Refer toDrive Belt Replacement .
6. Remove the fan and the pulley from the pump. Refer to Fan Replacement .
7. Disconnect the lower radiator hose from the pump.



8. Disconnect the coolant bypass hose from the pump.
9. Remove the coolant pump and the gaskets from the engine.
10. Clean the gasket sealing surfaces on the coolant pump and on the engine block.

Installation Procedure

1. Install new gaskets.
2. Install the coolant pump to the engine block.
3. Install the bypass hose.
4. Install the following parts to the coolant pump hub. Refer to Fan Replacement .

•	The coolant pump pulley

•	The fan clutch

5. Install the belt. Refer to Drive Belt Replacement :
6. Install the upper radiator shroud. Refer to Fan Shroud Replacement .
7. Fill the cooling system. Refer to Cooling System Draining and Filling .
8. Start the engine. Allow the engine to run with the radiator cap removed until the radiator upper hose is hot and the thermostat is open.
9. While the engine is idling, add coolant to the radiator until the coolant level reaches the bottom of the filler neck.
10. Install the radiator cap. Ensure that the arrows line up with the overflow tube.
11. Install the air cleaner duct.
12. Connect the negative battery cable.

Water Pump Replacement 4.3L

Removal Procedure

Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

1. Disconnect the negative battery cable.
2. Remove the air cleaner duct.
3. Remove the radiator shroud upper section. Refer to Fan Shroud Replacement .
4. Drain the coolant from the system. Refer to Cooling System Draining and Filling .
5. Remove the belt. Refer to Drive Belt Replacement in Engine Mechanical.
6. Remove the fan and the pulley from the pump. Refer to Fan Replacement .
7. Remove the lower radiator hose from the pump.



8. Disconnect the coolant bypass hose from the pump.
9. Remove the coolant pump and the gaskets from the engine.
10. Clean the gasket sealing surfaces on the coolant pump and on the engine block.

Installation Procedure

1. Install new gaskets.
2. Install the coolant pump to the engine block.
3. Install the bypass hose.
4. Install the following parts to the coolant pump hub. Refer to Fan Replacement :

•	The coolant pump pulley

•	The fan clutch

5. Install the belt. Refer to Drive Belt Replacement in Engine Mechanical.
6. Install the upper radiator shroud. Refer to Fan Shroud Replacement .
7. Fill the cooling system. Refer to Cooling System Draining and Filling .
8. Start the engine. Allow the engine to run with the radiator cap removed until the radiator upper hose is hot and the thermostat is open.
9. While the engine is idling, add coolant to the radiator until the coolant level reaches the bottom of the filler neck.
10. Install the radiator cap. Ensure that the arrows line up with the overflow tube.
11. Install the air cleaner duct.
12. Connect the negative battery cable.