Unfortunately, I have been dealing with a top gasket leak on a Billet pressure tank. What is the pressure these caps are designed to hold or give at? This tank is definately defective from day one, brought it to an aircraft machine and tool shop to build up the top sealing surface and get a good polished gasket mating surface, but they could not do anything with the bottom of the neck where the tabs of the cap ride (actually gets looser as you tighten the cap). Got the cap to hold to about 22 psi in a rad shop tank, but I wanted a goal of about 25 psi. This is a high horse, very high chrome engine which we could not even get to 170 degrees running without the cap leaking! I did order a replacement tank today but refuse to admit defeat easily on this one.
At what pressure is the top gasket designed to hold to? It should be the same for all pressurized automotive caps regardless of the lower gaskets ratings, correct?