Chainsaw Repair

The rings MUST be aligned correctly with the locating pin! Most pistons have the locating pin toward the top of the ring groove. The ring must be put on such that the rounded cutout on either end of the ring is aligned with the locating pin.

Not getting what you are saying about the circlip however Nothing should protrude outside the piston toward the cylinder wall. There is a groove inside the piston pin boss where the circlip goes, position the opening in the clip at the 12 or 6 o'clock position.

Here is an article on how to do the clips, is for a motorcycle engine but the process is the same
http://juicemotoparts.com/bearings