Bryan Porter wrote:use the copper one that comes with the gasket set.
I don't find a copper plug with a gasket.
My issue is the o-ring seal. I think a rubber seal will always allow loosening overtime.
Maybe I just need to replace the o-ring seal I have now with a nylon or copper washer/seal?
Jack Duncan wrote:Being a retired jet engine technician, my first thought was to drill a hole through the head and safety wire after it is torqued down.
Is this what you have Jack? You got a picture? I'd like to see what you wired it to, to keep it from loosening.