All,

I just opened up one of my old reed valve Cox .049s, to find a small amount of what I believe to be rust inside. Well, I think it is rust. It is a deep maroon colour, almost black.

It is mainly on the inside of the piston, with a little bit on the big end of the con rod.

Everything still moves smoothly, it wasn't gummed up. Compression is fine.

Is my engine doomed?

If not- can someone suggest a course of remedial action to save it.

Thankfully it seems to restricted to just the one engine, and even if it is crocked I have a TD .051 piston & liner I could substitute, thereby creating a reed valve .051.

cheers,
Colin