I am about to remove the engine head and replace the gasket on my halftrack. Do I need to put in gasket sealer on it before hand? Hopefully replacing the head gasket will fix the problem I had this summer. It had sat over the summer and when I got it started there was anti-freeze in the exhaust. I had always had a minor leak around the head, but I think it finally failed. It seemed to run fine otherwise, not that I ran it for very long.