. You can make a zero-pressure cap by removing the lower rubber gasket of the existing cap.
Jerry
Hey Jerry,
For an overflow tank to function, doesn't the radiator cap need to have a tight seal as the antifreeze cools off? The coolant loses volume as it cools, creating a vacuum which is the force that draws the coolant back out of the overflow tank. If the cap has had the seal removed, wouldn't that break the vacuum, preventing the coolant to be drawn back into the radiator? Maybe I don't understand how a pressure cap, modified by removing the lower seal works.
Carl
