Smitty Smithsonite
ArboristSite Operative
That skinny scuff line on the piston reminds me of a "4-corner" seizure, which happens when you don't warm up a 2-stroke, and just pull the cord and go right to cutting a 2' diameter oak. The piston grows quicker than the cylinder, and it seizes on the 4 widest points. A piston isn't perfectly round, and this becomes worse with heat, hence the 4-corner pattern.Sounds believable, but help me out here. What is it that leads you to thing that?
I'm afraid I'm not going to be much help to the inquiring minds out there as far as providing answers to what was wrong. With this being the first used p/c I've ever laid eyes on, I'm really not sure what I am looking at. To my inexperienced eye, it doesn't look like there is much grievous damage or scoring and the inside of the cylinder feels pretty smooth to me.
I don't see the corresponding scuff to the right of it in the pic, so probably not a 4-corner seizure, but could've got super hot from being slightly lean - either from improper mixture or from an air leak through the crank seals. Usually rings don't break when this happens - they'll stick hard in the piston. It's possible that the previous owner did a half-assed rebuild and never chamfered the ports, which snagged a ring. Piston clearance could've been too tight as well.