The Stovebolt Site Forums The Shop Area Engine Shop Radiator Blues

Ralph -
Here's what I did to slove the same problem you have. Remove your thermostat and drill a very small hall in the flat part of the thermostat. This hole will act as an air vent to allow trapped air to escape from your cooling system even if the thermostat is closed. Be sure the hole is away from anything that would block it when installed. The lip that the radiator cap seals against does need to be straight enough for the cap rubber to seal. Be sure you have a good (new) cap and that it is the right cap for your application. I also installed an after market overflow tank to catch any discharge as the engines warms. It will pull the fluid back into the radiator as it cools (just like new cars of today). This seems to have solved my problem. Hope it works for you. Good luck!