Head gasket sealant

[Ed McLawhorn Jr.]

What's folks using for head gasket sealant? Never had any issues with leaking until recently. Had water in #2 and yesterday discovered #1 and #2 bubbling thru radiator. Same block and heads. Fixed water in cylinder, ran a couple races and now found bubbling. No water loss. Used shim gaskets with spray copper coat. Have been using it for years. Same process, clean surfaces, spray copper coat, torque accordingly. Has anyone had issues with copper coat?

[FED 387]

We always used either Hylomar or Aluminum spray paint --with hylomar spray one coat on both sides let set for a few minutes (1-2) then install---with Alum paint spray both sides 3-4 light coats let dry til almost dry (3-4minutes) then install---- check both the block and head surfaces AND both sides of the gasket in that area for any SMALL scratches, nicks etc. that might be causing the problem too-FED 387

[ss3011]

Are they new shim gaskets or reused gaskets with copper coat ?

[Ed McLawhorn Jr.]

Originally Posted by ss3011

Are they new shim gaskets or reused gaskets with copper coat ?

They were new shims in the sense they never been used. They were old though...had been on the shelf for years. Wondering if they are not collapsing and sealing the raised edge on gasket?

I remember dad using aluminum paint sometimes too when he didn't have copper coat. Seemed to work pretty well too.

[Jeff Stout]

Copper coat has worked well for me. 12 to 1 and 175 HP nitrous. No problems

[Mike Pearson]

Sounds like you need to check the deck and head surfaces to make sure they are flat. Typically copper coat and shim gaskets is a good combo if everything is smooth and flat.