Thread: permatex for intake manifolds?

Tweet

Ultra Black is a RTV Silicone product. When you apply the material, it is relatively slippery before it cures, allowing for a gasket to easily slide. On a small block Chevrolet intake, the lower edge of each port is thin and the gasket can easily "squish" downward creating a serious vacuum leak. I would recomment that you NOT use an RTV Silicone on intake gaskets....use something thicker like the Gasgacinch or Permatex (the thick goo) applied very thinly.

It is OK to use RTV Silicone on the ends of the manifold.....the best way to close up the gap. Don use the end gaskets, just a fat bead of RTV.

mike in tucson

I have taken engines down apart and found RTV all over the pickup screen on the oil pump. For what thats worth...