Gasket Sealer
I agree with 10builder EZ turn on each side of the gasket and you shouldn't have any leaks. If you want the traditional solution go with Permatex Form a gasket type 3 in the round jar. I guess it all depends if you're going to be taking things apart in the near future. Every engine case I ever put together was with Permatex Aviation Form-a-gasket type 3. However, fuel pumps, magnetos, oil housings the EZ TURN works good. You need to put it on both sides of the gasket.