Pressure Cap Testing for Saturn L300/LW300 2001

Tools Required

J 43421 Cooling System Pressure Test Adapter

Caution: Refer to Radiator Cap Removal Caution in the Preface section.





Notice: If the vehicle has experienced cooling system boiling over, the pressure cap must be replaced.

1. Remove the pressure cap from the coolant surge tank.
2. Make sure that all parts of the pressure cap, tester, and adapter are clean.
3. Wet the rubber gasket of the pressure cap with water and install onto the J 43421 .
4. Hold the tester with the J 43421 hanging straight down.




Caution: Protect yourself by wearing safety glasses, earplugs, a respirator, gloves, and safety shoes while performing work on the vehicle.

Caution: Never pump the pressure cap above 152 KPA (22 PSI).

5. Pump the tester, watch the pressure gage, and read the maximum pressure before the relief valve opens. Stop pumping. The pressure cap is rated at 138 kPa (20 psi).

Specifications

•	The cap opening pressure is 138-145  kPa (20-21 psi).

•	The vacuum relief setting is 10 kPa (1.5 psi) below the atmospheric pressure.

6. Watch the needle for 30 seconds to see if it falls. The needle should not fall below 68.1 kPa (10 psi).