Thanks for responding. All your responses gave me some information to work with. I considered having the machined seating area kissed, and I may do that. However I noticed that the wall thickness at the bottom end of the bore diameter is no more than 1/16" thick while the top end is about 1/4 " thick. That is not much of a sealing surface on the bottom. It is not a very good sand casting and may have shrink in that area. I also compared the old copper seal ring to the one I received in the repair kit. The old one was .066" thick the new one is .039" thick. I good reason to buy NOS.They are both scratched up from assembly and disassembly. Anyone know where I could buy copper seal rings? Billy, when you loosened and tightened it 100 times, was it a quarter turn back and forth each time? Sounds like you made a groove in the sealing ring which increased the sealing surface. Don's idea about annealing the ring does the same thing except the soft ring is being squished. Did you use an Oxy-Acetylene torch? The ring didn't warp?