GM Service Manual Online
For 1990-2009 cars only

    Notice: Do not immerse the water pump in solvent. The solvent may enter the water pump's permanently lubricated bearings and cause premature bearing failure.

  1. Clean all gasket mating surfaces. Old gasket material must be removed and free of oil or other foreign materials.
  2. Inspect the water pump shaft for rotation and excessive end play.
  3. The shaft and fan hub must turn straight and smoothly.

    • If the hub wobbles or the shaft is noisy or feels "lumpy" when turned, replace the water pump.
    • If the shaft end play exceeds 0.381 mm (0.015 in), replace the water pump.
  4. Inspect the water pump body at the drain (weep) hole.
  5. Slight staining around the weep hole is normal.

  6. Replace the water pump only if coolant is dripping from the weep hole while the engine is running or while the system is pressurized.