2001 Mercury Mariner 50-60HP Factory Service Manual, Page 272Get this manual
CYLINDER BLOCKCRANKCASE
Connecting Rod Installation
1Lubricate the piston pin with oil and assemble the piston to the connecting rodAlways use new circlipsIMPORTANT: Install the split end of the circlip into the groove first, push the other end down until it snaps into the grooveIf the shape of the circlip is permanently distorted when attempting installation, discard it and use new oneIMPORTANT: Install side of connecting rod marked with "Y" towards "UP" on piston faceIMPORTANT: Piston pin clip should be installed with end gap facing opposite of pry point110