[craigayl]

Back in Black

If the cork seals are too thick or not properly trimmed where they mate with heads, they can cause the intake to not come down properly on the intake to head gasket which can cause both cooling leaks and vacuum leaks. For this reason, some mechanics will abandon the cork seals for RTV only. However, if proper procedures are followed to check the end gap vs the cork thickness and that the cork is properly trimmed to mate to the heads, the cork will add little more rigidity to the seal than RTV alone. Some cork end seals come with adhesive on the bottom side, in which case you would only add a thin layer of RTV on the top side. If there is no adhesive, a thin layer of RTV on both sides should be used.

I have installed many intake manifolds and have always used the cork gaskets without incident. Either system is acceptable, but I surely would NOT recommend removal of an intake because it has cork seals. They MAY have been properly installed and are very acceptable

Craig