Decided to fix another oil leak and was pretty sure what the problem was since I've fixed the other five on my O 470K the last few years. The folks in Omaha that rebuilt the engine sent Superior silicone gaskets this time so I must not be the lone ranger with gaskets shrinking.

SAP gaskets are horrible. I spoke to a rep about them at Airventure. He didn't want to talk about it or admit to anything, but his shame wasn't disguised. I think they've fixed the problem. Genuine Continental works better. The silicon ones are good, but you have to be sure that all surfaces are bare and dry. Any oil, and they'll slip out and leak.

SAP valve covers also have issues. You'll find that they had a run with a flaw where the facing cutter passes overlapped. Also, they're painted or powder coated. Best to lap them with a piece of glass and some sandpaper.