GM Service Manual Online
For 1990-2009 cars only

Water Crossover Cleaning and Inspection C/K/G/C3500HD

Cleaning Procedure


    Object Number: 635643  Size: SH
  1. Clean the coolant crossover (7) and water outlet (1) in solvent.
  2. Caution: Wear safety glasses in order to avoid eye damage.

  3. Dry the coolant crossover and water outlet with compressed air.

Inspection Procedure


    Object Number: 635643  Size: SH
  1. Inspect the coolant crossover (7) for the following:
  2. • Corrosion or damage to the gasket sealing surfaces (5)
    • Corrosion or damage to the bypass hose fitting (6)
    • Corrosion or damage to the heater hose fitting (8)
    • Corrosion or damage to the threads for the water outlet (4)
  3. Inspect the water outlet (1) for corrosion or damage.
  4. Repair or replace the coolant crossover and/or water outlet as necessary.

Water Crossover Cleaning and Inspection Medium Duty

Cleaning Procedure


    Object Number: 635646  Size: SH
  1. Clean the coolant crossover (3) and water outlet (1) in solvent.
  2. Caution: Wear safety glasses in order to avoid eye damage.

  3. Dry the coolant crossover and water outlet with compressed air.

Inspection Procedure


    Object Number: 635646  Size: SH
  1. Inspect the coolant crossover (3) for the following:
  2. • Corrosion or damage to the gasket sealing surfaces (4)
    • Corrosion or damage to the bypass hose fitting (5)
    • Corrosion or damage to the threads for the water outlet (2)
  3. Inspect the water outlet (1) for corrosion or damage.
  4. Repair or replace the coolant crossover and/or water outlet as necessary.