Reply To: Basic piston ring questions

[Tom]

Keep in mind that pistons rings need to seal in two places. The cylinder wall is the obvious place, but they also need to seal against the bottom of the ring land. Be sure the ring lands are free of carbon and corrosion. Don’t use anything sharp to clean the lands, scratches and gouges are to be avoided.

I’ve taken an old ring and sanded the top and bottom surfaces with 220 grit wet and dry paper on a surface plate to get them smooth. Then loaded up a piston groove with polishing compound. With that done, load the piston and ring into its cylinder. Move the piston up and down in the bore while twisting the piston back and forth. This does a pretty good job of polishing the lands, but you have to thoroughly clean the piston lands and cylinder when you’re done.

T