Radiator Cap: Testing and Inspection

RADIATOR CAP SUB-ASSY INSPECTION


NOTICE:
^ If the reservoir cap has contaminations, always rinse it with water.
^ Before using a radiator cap tester, wet the relief valve and pressure valve with engine coolant or water.

a. Using a radiator cap tester, slowly pump the tester and check that air is coming from the vacuum valve.
Pump speed: 1 push/(3 seconds or more)

NOTICE: Push the pump at a constant speed.

If air is not coming from the vacuum valve, replace the reservoir cap.
b. Pump the tester and measure the relief valve opening pressure.
Pump speed: 1 push within 1 second

NOTICE: This pump speed Is for the first pump only (in order to close the vacuum valve). After this, the pump speed can be reduced.

Standard opening pressure: 93 - 122 kPa (0.95 - 1.25 kgf/cm2, 13.4 - 17.6 psi)
Minimum opening pressure: 78 kPa (0.8 kgf/cm2, 11.2 psi)

HINT: Use the tester's maximum reading as the opening pressure. If the opening pressure is less than minimum, replace the reservoir cap.