Help me make a valve cover gasket

September 1, 2016 | By Staff


I needed to adjust the valves on my 1936 Chevrolet and in the process of doing so I tore the old valve cover gasket in a couple of places. As a result, I need to replace it but it seems I must purchase a whole new gasket set because they don’t offer this gasket separately. I know the gasket material is available at the auto parts store, but I am reluctant to try cutting one. Have you done it, and if so, how do I do it?


Cork gaskets are a little bit tricky to make, but they’re no big deal. Obviously, you can’t cut them out with a ball peen hammer like you can fiber gaskets, but you can still use the aerosol paint trick to make your pattern. You just lay the remains of your old seal on the new cork material and give it a fine mist with whatever rattle can paint you have available. And then, because of the thickness of the material, take a pencil and mark the screw holes too. A hole punch (Harbor Freight sells them for $9 a set) or even a pencil with the eraser pulled out of the sleeve can be used to cut the new screw holes.

Use a sharp utility knife and be extra careful when cutting out a cork gasket though, because cutting cork is a little like slicing fresh bread. It takes a sharp knife and several light passes so as not to scrunch and tear the material. If you try to cut the cork in one determined swipe, it will bunch up and distort and ruin the gasket material. Afterward, I like to give the gasket a coat of Permatex Form-A-Gasket on just one side, and then stick it to the valve cover only, so the valve cover can be removed without drama later when you have to adjust the tappets again.

rk gaskets is to just snug up the screws or bolts holding the mating surfaces together. If you keep on tightening beyond the point at which the gasket is held firmly in place, the material will squeeze out like pizza dough from between the mating surfaces. Also, you run the risk of distorting the sheet metal valve cover and causing a leak.