Mercury 35/40HP 2 Cylinder Outboards Service Manual PN 90-42794--1, Page 86Get this manual
Now insert piston pin tool ("au 91-76159A1) and push sleeve (b) out of piston as shownKeep piston pin tool in piston Install new piston pin Lockrings ("b one each end of piston pin) using Lockring Installation Tool ("aU 9177109A1) as shownMake sure Lockrings are properly seated in piston grooves