Mercury Mariner 200, 225 Optimax Outboards Service Manual, 90-855348, Page 388Get this manual
Gear Lubricant Filling Instructions 1Inspect "Fill" and "Vent" sealing washers for cuts or abrasionsReplace O-rings if necessary2Clean any metal debris from magnet on "Fill" plug
Installing Gear Housing to Drive Shaft Housing
Disconnect high tension leads from spark plugs and remove spark plugs from engine before installing gear housing into drive shaft housing1Tilt engine to full up position and engage the tilt lock lever2Apply light coat of 2-4-C wlTeflon onto drive shaft splines
IMPORTANT: Never add lubricant to gear housing without first removing "Vent" screw, or gear housing cannot be filled because of trapped airFill gear housing ONLY when housing is in vertical position3Slowly fill housing thru "Fill" hole with Quicksilver Super Duty Lower Unit Lubricant until lubricant flows out of "Vent" hole and no air bubbles are visible4Install "Vent" screw into "Vent" hole