LEMON Manuals: Even more car manuals for everyone
Home >> Hummer >> 2003 >> H2 >> Repair and Diagnosis >> External Pages >> Different car >> Section 909 (Engine Cooling System) >> Diagnostic Information and Procedures >> Pressure Cap Testing

Pressure Cap Testing

WARNING: This page is about a different car, the 2009 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

Special Tools

    WARNING: To avoid being burned, do not remove the radiator cap or surge tank cap while the engine is hot. The cooling system will release scalding fluid and steam under pressure if radiator cap or surge tank cap is removed while the engine and radiator are still hot.
  1. Remove the pressure cap.
  2. Wash the pressure cap sealing surface with water.
  3. Fig 1: Pressure Testing Radiator Cap
    GM850101Courtesy of GENERAL MOTORS CORP.
    NOTE: Lubricate J-42401 and pressure cap O-rings with coolant and press cap to seat the O-ring on J-42401 before turning to engage threads.
  4. Use the SA9141E  (1) with J 42401  (2) in order to test the pressure cap. See Special Tools .
  5. Test the pressure cap for the following conditions:
    • Pressure release when the SA9141E  exceeds the pressure rating of the pressure cap. See Special Tools .
    • Maintain the rated pressure for at least 10 seconds.

      Note the rate of pressure loss.

  6. Replace the pressure cap under the following conditions:
    • The pressure cap does not release pressure which exceeds the rated pressure of the cap.
    • The pressure cap does not hold the rated pressure.