Pressure Cap Testing

Tools Required

• J 24460-01  Cooling System Pressure Tester. See Special Tools .
• J 42401  Radiator Cap/Surge Tank Test Adapter. See Special Tools .
• J 46143  Intercooler Reservoir Cap Test Adapter. See Special Tools .

CAUTION: 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.
1. Remove the pressure cap.
2. Wash the pressure cap sealing surface with water.
Fig 1: Pressure Testing Radiator Cap
Courtesy of GENERAL MOTORS CORP.
3. Use J 24460-01  (1) with one of the following attachments (2). See Special Tools .
   • J 42401  in order to test the radiator cap. See Special Tools .
   • J 46143  in order to test the intercooler reservoir cap. See Special Tools .
4. Test the pressure cap for the following conditions:
   • Pressure the release when J 24460-01  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.

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