Ok guys, got a problem I haven't had before and it has us stumped. This engine is a Briggs 33 with 10 races on it. Pulled it apart yesterday to freshen it up and the piston has been touching the head on the spark plug side. It has an ARC rod and stock piston, I wouldn't think the rod stretched but if it did I think the piston would hit all the way around not just on the one side? Maybe something went wrong with the piston? Any ideas??