Mercury Mariner Outboard 225 3 Litre Service Manual 1994, Page 222Get this manual

Mercury Mariner Outboard 225 3 Litre Service Manual 1994, Page 222

9 Pull gear housing from drive shaft housingPosition clean drain pan under gear housing and remove "Fill" and "Vent" screws from gear housingDo not loose O-rings on Fill and Vent screws-

aSide Mounting Locknut (2 Each Side)

DRAINING AND INSPECTING GEAR HOUSING LUBRICANT
1Place gear housing in suitable holding fixture or vise with the drive shaft in vertical position
a "Fill" Screw