Water Pump Cleaning and Inspection
WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
- Inspect the water pump pulley for damage at the belt contact area (1) and the pulley-to-water pump mounting surface.
- Clean all excess dirt and debris from the water pump housing.
- Inspect the water pump for the following:
- Leakage at the hose fitting (1)
- Leakage at the water pump weep hole (3)
A stain around the weep hole is acceptable. If leakage occurs, dripping with the engine running and the cooling system pressurized, replace the water pump.
- Gasket sealing surfaces (2) for excessive scratches or gouging
- Restrictions within the internal coolant passages (6)
- Excessive side-to-side play in the pulley shaft
If the shaft end play exceeds 0.381 mm (0.015 in), replace the water pump.
- Rotate the pump shaft by hand and inspect for roughness of operation
- If the hub wobbles, is noisy or feels rough when rotated, replace the water pump.
- The shaft and fan hub must turn straight and smoothly.
- Damage to threaded bolt holes (4)
- Damage to the fan clutch mounting threads (5)
IMPORTANT:
Do not immerse the water pump in solvent. The solvent may enter the water pump's permanently lubricated bearings and cause premature bearing failure.