I had a nearly identical issue two years ago. Motor over heating, blowing fluid out of the overflow container. I used the dye test, turned green, just like yours. Got a pressure tester on it, it was leaking a little pressure but hardly much at all.
I ended up pulling the head. The copper head gasket had failed in just one tiny area, and was letting combustion pressure into the cooling system. It was such a small failure, it took time to build up. I had Rebuilt another head (just in case it was a crank in the head).
Put the new head on with a fresh felpro blue gasket. I opted not to use one of my spare copper gaskets and went with a fresh composite gasket. The over heating stopped.
Took the old head back to machine shop, turns out the head, which I rebuilt many years ago was likely the cause of the gasket failure. The machining on the head surface was rougher than what is done today.
Last edited by Dragsix; 09/23/2024 2:20 AM.
