Cooling tube fell off. Engine overheated.

Cylinder
Super minor scratch in cylinder (barely barely feel it when you drag your fingernail across it)

Piston
Piston has a moderate score on the skirt (one veritical line; the picture makes it look much worse than it is).

I am a nitro guy, this is my first gasser.
I would rather not replace the piston and certainly not the cylinder if possible (it's an M5 mod engine from WHH.

Ideas? Can I simply sand the score down on the piston slightly and put a new ring on her?

I have seen worse! Typically if the cylinder isn't scored, you can use some steel wool on the piston (while turning the piston) to smooth out any material sticking out. No need to over do it. Put a new ring in and treat it like a new engine and break it in to seat the ring. It might not run as good as before, but only trying it will tell. Assuming nothing else is damaged of course.

The best thing of course would be to swap the damaged parts, but in all honesty I have run some that looked worse and actually ran pretty good. We all went through a learning curve! I went through this kind of stuff when the 260s first came out and we were modifying them without turning down the top of the pistons!

Try it and see. A ring is cheap.

gizmo motors has g260 head kits for $44.oo on ebay free shipping. can't beat that.

I have seen 260 jugs that were scored up so bad you would not think it would even run (i know i didnt) and it ran like a raped ape.

Like Marc said... run it and see.