Thanks Jeff! I didn't know about the 12 year seal lifetime. I'm surprised that my mechanic didn't mention that little fact when I had him do an AD search on my engine. The P/N of the seal (SL-76940) is apparently the split seal type rather than the stretchy one so I won't have to stretch it over the propeller flange. Whew! Any words of wisdom on installing the new seal would be much appreciated.

Four hours on it since 1991. Wow! It is actually beyond TBO by ten years. Lycoming says xx hours (depending on engine)  or 12 years whichever comes first. Some things wear out from use. Some wear out from disuse.

 

Jeff