Water Pump Cleaning and Inspection L98, LS2

1. Remove the old gasket from the water pump sealing surfaces. Refer to Replacing Engine Gaskets.
2. Remove the thermostat, if necessary. Refer to Engine Coolant Thermostat Replacement.
3. Clean all excess dirt and debris from the water pump housing.
4. Inspect the water pump for the following conditions:

•	Gasket and hose sealing surfaces for above acceptable scratches or gouging.

•	Restrictions within the internal coolant passages.

•	Above acceptable side-to-side play in the pulley shaft.

•	Leakage at the water outlet housing or rear cover gasket.

•	Leakage at the water pump vent hole.

•	A stain around the vent hole is acceptable. If leakage, dripping, occurs with the engine running and the cooling system pressurized, replace the water pump.

•	Wear or damage in the belt tracking area of the pulley.

Water Pump Cleaning and Inspection LS3

1. Remove the old gasket from the water pump sealing surfaces. Refer to Replacing Engine Gaskets.
2. Clean all excess dirt and debris from the water pump housing.
3. Inspect the water pump (1) for the following conditions:

•	Gasket and hose sealing surfaces for excessive scratches or gouging

•	Restrictions within the internal coolant passages

•	Excessive side-to-side play in the pulley shaft

•	Leakage at the water outlet housing or rear cover gasket

•	Leakage at the water pump vent hole

•	A stain around the vent hole is acceptable. If leakage, dripping, occurs with the engine running and the cooling system pressurized, replace the water pump.

•	Wear or damage in the belt tracking area of the pulley