On my 22re I have a 3 core radiator. Has anyone had the problem of coolant going to the reservoir when hot but not sucking back into the radiator when it cools? I checked and system holds pressure. Even has a sucking sound when opening the cap after a drive. Has new overflow hose. I think the culprit is the radiator cap. Which cap would have less spring pressure on the return valve? The stock radiator cap doesn't fit the neck. Please help. Thanks

 

What ever cap is rated for the pressure your cooling system calls for.

In theory any cap from 10.7 to 14.9 psi

Simple to test the cap if you have a cooling system pressure tester something I think is a must have.

Are you sure your using the correct hose from the over flow tank to the radiator I have seen some just collapse when the coolant is being pulled back towards the radiator.

Are you having over heating or lack of heat?? losing coolant?? Problems

If not I myself would not be overly concerned .

Back in my misguided youth no vehicles had over flow tanks.

 

Thanks for the reply. I tested the cap release point as well as testing with a vacuum pump the return valve. It worked effortlessly. But after a 200 mile drive and cool down, I have about a liter low in the radiator. I cleaned the reservoir thinking there was something blocking out flow. I also suctioned the filler neck side of the hose, draws easily. I pressure tested the system, was ok. Maybe the vacuum collapses the radiator hoses enough to raise the level 1 liter when cool. then when I loosen the cap the level drops as the hoses flex back. The main hoses aren't very old. Next time I drive it and the level falls I will squeeze the main hoses and see if the level rises. What is going on? Thanks