Radiator Cap to Filler Neck Seal

RADIATOR CAP-TO-FILLER NECK SEAL

The pressure cap upper gasket (seal) pressure relief can be tested by removing the overflow hose from the radiator filler neck nipple. Attach the hose of pressure tester tool 7700 (or equivalent) to nipple. It will be necessary to disconnect the hose from its adapter for the filler neck. Pump air into the radiator. The pressure cap upper gasket should relieve at 131 kPa (21 psi) and hold pressure at a minimum of 130 kPa (18.8 psi).

WARNING: The warning words DO NOT OPEN HOT on radiator pressure cap, are a safety precaution. When hot, pressure builds up in cooling system. To prevent scalding or injury, radiator cap should not be removed while system is hot and/or under pressure.

Do not remove the radiator cap at any time except for the following purposes:

1. Check and adjust the antifreeze freeze point.
2. Refill system with new antifreeze.
3. Conducting service procedures.
4. Checking for vacuum leaks.