2000 XL800 strange markings on both pistons

[NCPWC]

Hi All,

I recently purchased an xl800 with low compression in the PTO cylinder... After tearing down I spotted a disconnected oil line on the PTO carb so I am fairly sure that is the culprit, but also some strange markings on the top of both the PTO and Mag pistons in about the same place and basically the same 2 small gouges. Any ideas on what could cause this?

MAG:


PTO:


Thank you!

[jeffg426690]

Remove jugs and see you if rings are completely intact - looks like gouges from pieces of ring material (although typically there is a lot more...) Common

[water worx]

My guess is you got something coming apart....

[NCPWC]

I figured as much, just seemed kind of strange that they were the same markings in the same spots on both pistons. Planning on putting the cylinder head back on and getting some compression numbers before I pull the engine and tear it down. I'll post up anything that I find.

[jeffg426690]

I wouldn't bother with getting compression now - not worth any effort, the jugs already tell you it has to come apart.

[water worx]

That first pic looks like it was honed with a dull deer antler. LOL

[NCPWC]

Well, I got around to taking the cylinders off... I suppose a new set of rings and it is good to go right? . Most everything else felt alright to me. The crank rotates smooth and there is very little sideways play in the rods. Is there anything else I should be careful about in here?

I have the cylinders at my work, plan on getting ovality and diameter readings at lunch (bonus of working at a place with a machine shop). I am hoping I can clean up the bad cylinder with some scotch brite/honing stone or some muriatic acid.