[foxox]

I tried using RTV to fix one that was cracked once, but it didn't help at all.

I think one of my tubes of RTV says in the gasket-making instructions to let the stuff set for a while before putting the pieces together, so that there will be a firm layer of the stuff to squish against, rather than just having it squish out of the joint and drying flattened. I wonder if you could use enough of the stuff in this application to form a raised bead, then let it set up some, then put the things back together.

What sort of temperatures are there at the intake side of the engine? 250F? 300F? 350F?

[steves]

The oil cooled engines use gauges that read up to 500*F for internal temps... so it could be at least that high.