Non-Mooneyguy

Wow Aerodon-- very helpful, and your knowledge / access to information is great. Clarifying: engine needed: L1C5, Donor: K1G5. ...and since you identified the only 2 platforms Lycoming lists it for, you prob appreciate how rare the L1C5 is. My original question was about roller tappets, but after stumbling on yall's discussion here, I further researched and concluded that roller tappets don't impact compatibility, and this donor engine, while made in 1980, was overhauled in 2013, so I assume got its "E" designation then. Roller tappets aside ,that leaves me with the question of whether a sump and/or the other L1C5-specific components are going to be in the overhauler's warehouse. If not, that leaves the possibility of your concept of "get everything overhauled (on the K-donor) and ready to go, and at the last minute overhaul and bolt the different parts from my (L) engine." I think this is as far as I'll get, because there's no one left to ask about the sump (etc.) availability that I know of. Thanks a lot for your thoughtful response. And while I feel guilty for crashing yall's forum, I promise I'm a net "giver" in the rest of the really specific forums I'm in, start new threads, etc., along with my other middle aged / aging compadres there.

You're right-- since I had to make a decision by tomorrow, I was kindof hoping to take advantage of the fact that the knowledgeable engine conversion folks on this thread would get a ping when I posted, vs getting lucky someone was browsing new topics. Sorry to poke my nose in like this.

Gentlemen, Because of the lack of exchange engines, I'm buying an old core to have a well known overhaul company overhaul, and then put in my plane. (this is how I'm getting comfortable buying a 1999 hour plane. (I know I could run it on condition ,etc). I haven't been able to get anyone to confirm that conversion from the old core to my existing model is possible, besides the (very nice) sales people at the overhaul shop (can't speak to the technicians, and it's all "don't worry, it's fine, etc.," third-hand. (Lycoming won't comment). I saw your roller tappet discussion, and thought as a very big favor one of you could weigh-in. I've been told that these are both wide deck, but that the "E" ending of the serial number means the donor has roller tappets, which besides me not know what they are, doesn't make sense because I was told it was manufactured in 1980. Old "donor" core I am thinking of buying: Model IO-540-K1G5, Serial: RL-28069-48E Engine in the airplane (overhaul shop says they could convert the donor "K" engine to this "L" engine, for swap in with no type-certificate modifications, etc): Model IO-540-L1C5, Serial: L29-144-48A Thanks in advance for your help. Will buy a beer.