107 engine: what happened? Should I run it? Or swap it?

[Cubcadet_107]

Originally Posted by Ambush

If you plan to swap it, you have to pull it anyway. Why not pull it apart and check/clean everything? Might be just as easy to fix the original instead putting time and money into the donor.

I don't need to put much of anything into the donor except the external parts. The money would be needed on the original engine. Even if nothing is wrong, I would still prefer to get it rebuilt properly, unlike whoever last rebuilt it did.

I still cannot believe that they would install the wrong size piston! I should've taken a picture of all the slop it has. I know they wear from side to side, but the slop is all the way around the whole piston! And it's an even gap all the way around too. The piston is stamped 'std', and my guess is that the bore is actually .010" oversize.

Then again, based on the quality I've found elsewhere on the engine, this mistake isn't surprising to me. Keep in mind this engine has misc. washers all over the place, the reed valve was installed backwards, and the points plunger is a section of what appears to be a drill bit

I hope my reasoning makes sense, there's more issues than just the possible metal in the oil. I want to keep this tractor going for shows this year, and swapping the engine for one that I know is in good shape, seems like the best way to go.