What sealant do you use as red high temp rtv sealant was/is useless. (unless I need a much bigger blob) I'll try again tomorrow.there push fit and peened over slightly in the block, just clean around the base of it out side the block with brake cleaner and put a big blob of gasket sealent round it. they come loose when people chemical/bake clean the blocks and dont take them out to re-seal them.