I have three rings that have a O stamped on them. Three that don't. These are for 98 mach z. Are the ones with the O the oil ring? Do theses's go on the bottom or top? And what do you do to prep the nickasil cylinders before I put them back together.
Thanks


SWRules

The three with the o should be the compression rings and go on top, the o shoud face up. Rotax says nothing needs to be nicasil on a re-ring job, just clean assemble and go.

I can't see the crosshatch marks very well. I should still get the cylinders honed right. If you don't have crosshatch marks the rings will not seat like their suppose too. Iam I correct? What about wiseco pistons any good?
SWRules

I've been taught that the rings won't seat right without the crosshatching.