I am wondering if it is possible you are over tighten the bolts and it is crushing the cork.I always use yellow 3m weather stripe cement on the block to hold the gasket in place. Then rtv or ultra on the ends as Larry mentioned.Yeah,I no that Monkey glue is hard to remove...hehehehe the bolts just need to be a little tigher than snug maybe like 20-25 INCH lbs.

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