What is the acceptable amount of varnish buildup on cylinder wall? Can I just replace the rings? Or do I have to bore the cylinder and new piston and rings?
The crown of the piston has a lot of dry carbon film on it .Exhaust side of cylinder is wet like an oil fouled plug.I found this because I took the head off to have Larry Wiechman' s compression release installed. 87 K 5. Tried to post photos but couldn't.