Hi, All;

I know a lot about auto engines; was a certified auto tech before I received my degree; have assembled many.

I don't know much about aircraft engines other than the obvious stuff / mostly accessories / owner maintenance items.

So it dawned on me: If I'm wanting something like an O-200 for my experimental aircraft project, I know I'll want to tear it down for inspection. I'm aware that there are overhaul manuals all over eBay. But, aside from textual descriptions of engines for sale, how do I pick one? I know it's not a good indicator to rely only on hours SMOH, etc., and some known salvage yards at least will state prop strike or not, but aside from that, and whether or not the accessories are included, is it just a crapshoot? Any words that would tip one off (aside from a prop strike) that the case might need to be line-bored, for example? Are there a good set of questions one should ask to get some indication of the quality of a used engine?