JW51,
I don't believe Permatex's "The Right Stuff" is silicone but rather some type of rubber. It seals very well without seepage. I have used it on transmissions, oil pans, push rod covers and valve covers. It is very adhesive so, for example, on the valve cover I use it between the head and gasket so oil doesn't seep under the gasket where is puddles at the rear of the engine. Makes removing the valve cover easy. You wouldn't want to use it on an assembly that you expect to remove soon.
I don't like the name, very corny, but I like the product.
Kent
