GM Service Manual Online
For 1990-2009 cars only

Cleaning Procedure

    Notice: Refer to General Repair Instructions in the Preface section.

  1. Remove the old gasket material from the water pump sealing surfaces.
  2. Clean all excess dirt and debris from the water pump housing.

Inspection Procedure


    Object Number: 1961587  Size: SH
  1. Rotate the water pump hub (1). The water pump hub and impeller should turn straight and smoothly. If the hub wobbles, is noisy, or feels rough when rotated, replace the water pump.
  2. Inspect the exterior of the water pump for the following:
  3. • Damage to the water pump hub bolt threads (2) for the water pump pulley
    • Damage to the water pump bolt holes (3)

    Object Number: 1961588  Size: SH
  4. Examine the water pump shaft (1) and the weep hole (2) in the water pump body for signs of leakage. If coolant leakage is evident, replace the water pump.

  5. Object Number: 1961589  Size: SH
  6. Inspect the interior of the water pump for the following:
  7. • Damage to the water pump gasket sealing surface (1)
    • Damage, corrosion or restrictions to the water pump impeller (2)
    • Damage, corrosion or restrictions to the coolant passages (3)
  8. Repair or replace the water pump as necessary.