912ULS borescope

I don't see any reason to remove your cylinders.

If your concerned I would fly for 10 hours and borescope again.

Your pictures do not indicate the engine is in jeopardy.

The last thing you want to do is take wrenches to the problem until the last resort.

Chuck

The cylinders are not steel, so this is not corrosion.  It appears to be fuel residue from the combustion. 

Cheers

I agree with RW. Actually they don't look bad and I see no reason to remove the cylinders and maybe open a door you wish you hadn't opened.

Boroscopes magnify things significantly.  That's probably just mogas and avgas residue...

Out of curiosity, what boroscope did you use?

Thanks.  

Brett H

Columbus, IN