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Testing Procedure

    WARNING:

    Under pressure, the temperature of the solution in the radiator can be considerably higher, without boiling. Removing the radiator cap while the engine is hot (pressure is high), will cause the solution to boil instantaneously, with explosive force. The solution will spew out over the engine, fenders, and the person removing the cap. Serious bodily injury may result. Flammable antifreeze, such as alcohol, is not recommended for use at any time. Flammable antifreeze could cause a serious fire.

    WARNING:

    In order to help avoid being burned, do not remove the radiator cap while the engine and the radiator are hot. Scalding fluid and steam can be blown out under pressure if the cap is removed too soon.

    WARNING:

    Refer to Radiator Cap Removal Warning .

    WARNING:

    Refer to Safety Glasses Warning .

  1. Ensure engine is below 50 °C before removing the coolant pressure cap.
  2. Fig 1: Locating Sealing O-Rings
    GM1949744Courtesy of GENERAL MOTORS COMPANY
    NOTE:

    Only use water to wet the cloth.

  3. Inspect and clean the sealing O-rings (1) with a wet cloth.
  4. Fig 2: Pressure Cap Adapter, Pressure Tester Adapter, Cooling System Pressure Tester & Coolant Filler Cap
    GM1949741Courtesy of GENERAL MOTORS COMPANY
  5. Attach the coolant filler cap (1) to J-24460-A  Cooling System Pressure Tester or a commercially available cooling system pressure tester (2), using the pressure cap adapter (4) and the pressure tester adapter (3).
  6. NOTE:

    Should the coolant pressure cap fail to reach or hold the specified pressure, replace the cap.

  7. Slowly pressurize cap to 120 - 150 kPa (17 - 22 psi).
  8. Prior to installing the coolant pressure cap ensure that the coolant filler neck cap seating surface (1) is clean and free from obstruction.
  9. Install the coolant pressure cap.