Mercury Mariner Outboard 225 3 Litre Service Manual 1994, Page 152Get this manual
4 Insert piston pin tool (91-92973A1) and push sleeve out of pistonKeep piston pin tool in pistonMake sure lockrings are properly sealed in pistor grooves_
a Piston Pin Tool (91-92973Al- Sleeve
Use mallet and tap piston pin into piston and push piston pin tool out
aLockring Installation Tool (91-93004A2) Lockring