Water Pump Replacement Caterpillar

Refer to the Caterpillar® Service Manual.

Water Pump Replacement L18

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. Reposition the bypass hose clamps at the water pump and water crossover.
7. Remove the bypass hose.



8. Remove the water pump bolts.
9. Remove the water pump.
10. Remove and discard the water pump gaskets.

1. Place NEW water pump gaskets into place.
2. Install the water pump.

Caution: Refer to Fastener Caution in the Preface section.

3. Install the water pump bolts.

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




4. Install the bypass hose.
5. Position the bypass hose clamps at the water pump and water crossover.



6. Install the outlet hose to the water pump.
7. Position the outlet hose clamp at the water pump.
8. Install the fan clutch. Refer to Fan Clutch Replacement.
9. Install the drive belt. Refer to Drive Belt Replacement for the 8.1L engine.
10. Fill the cooling system. Refer to Cooling System Draining and Filling.

Water Pump Replacement 7.8L

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:

•

The clamp

•	The heater hose




5. Remove the bolts from the water duct.
6. Remove the following components:

•	The water duct

•	The O-ring




7. Remove the water pump bolts.
8. Remove the following components:

•	The water pump

•	The gaskets

9. Clean the following components:

•	The surface of the water pump

•	The surface of the engine block

•	The bolt threads

•	The water duct sealing surfaces

10. Inspect the following components for wear, deterioration or corrosion.

Replace the components as necessary:

•	The clamps

•

The hoses

•	The water pump

1. Install new gaskets to the water pump.
2. Install the water pump to the engine block.

Caution: Refer to Fastener Caution in the Preface section.

3. Install the water pump bolts.

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




4. Lube the O-ring with soap suds.
5. Install the following components:

•	The water duct

•	The O-ring

6. Install the water duct bolts.

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).
7. Install the following components to the water pump:

•	The heater hose

•

The clamp

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




8. Install the adapter (2) to the pump.

Tighten
Tighten the adapter bolts to 68 N·m (50 lb ft).

9. Install the fan clutch. Refer to Fan Clutch Replacement.
10. Install the drive belt. Refer to Drive Belt Replacement.
11. Fill the cooling system. Refer to Cooling System Draining and Filling.
12. Inspect the system for leaks.

Water Pump Replacement 6.6L

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. Remove the water pump to engine coolant pipe nuts.
5. Remove the engine wiring harness retainer from the inner stud.



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

1. Lubricate the water pump O-ring with engine oil.
2. Install the engine coolant pipe gasket and water pump O-ring.
3. Install the water pump.

Caution: Refer to Fastener Caution in the Preface section.

4. Install the water pump bolts. Ensure the correct length bolt is used in the proper location.

Tighten
Tighten the bolts to 21 N·m (15 lb ft).

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



6. Install the water pump to engine coolant pipe nuts.

Tighten
Tighten the nuts to 21 N·m (1 lb ft).

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