My 8N ford tractor has a loud clatter...

I found the cause, the exhaust gasket has blown out in a small spot. The
metal in the block is slightly burned away. ( a couple years ago, I put a
new manifold on so its in good shape here) Its a flat head engine so the
ports are in the block not on the heads. And to make matters even worse the
block on a tractor is the frame support also. No way can I take the thing
apart enough to re-machine this surface.

So, do they make some sort of gasket goo to add to the manifold gaskets that
will correct this problem?

Karl