I have new rings coming from Mr. Bowmwn. Would some of you share your technique for prepping the used cylinder to ensure the new rings will seat good.

With our typical gas engines used in models having Nickasil and chrome plated cylinders do not be too aggressive on prepping the cylinder.

What does Frank Bowman recommend??

Your best bet is to just clean the bore thoroughly, check for gouges or any piston material stuck to the chrome, make sure there is no carbon deposits in the exhaust port at the edge where the port meets the cylinder.

Atool to clean up the bore in the typical finger ported lawn tool cylinder costs more than a new cylinder, you can't go in there with the usual spring loaded cylinder hone and expect to do anything other than ruin the hone and the cylinder.

Frank recommends light sanding with 400 or 600 grit sandpaper, followed by a good cleaning. I like to clean mine with spray carb cleaner, and then soap and water. When you can pass an oiled piece of paper towel over the bore surface without it getting dirty, the cylinder is clean.

AV8TOR

My cyl has what looks like burnt oil or vanish in places. Would a product like Berrimans carb cleaner be a good choice, I've used it to de-varnish carbs with good result, it's more powerful than Gumout.

Won't hurt....

AV8TOR