1985 Mercury Outboard V-300 V-3.4L Shop Service Manual, Page 168Get this manual
DRAINING and INSPECTING GEAR HOUSING LUBRICANT i Place gear ho using in suitable holding fixture or vi se with th drive shaft in vert ical position.as shown in 8
2Position clean drain pan under gear housing and removeFill" andVent" screws (Figure 8) from gear housing3In spect gear lubricant for metal parti clesPrese nce of small amount of fine metal particles (resembling po wderindi cat es normal wearPrese nce of larger particles (or large quan tity of fine part icles) indicates need for gear housing disassembl yand componen inspection 4Note th color of gear lubricantWh ite or cream co lor
a" Fill" Screw"Vent" Screw (lower)"Vent" Screw (upper) Figure 8Draining Gear Housing
indicates presence of water in lubricantCheck drain pan for wate separati on fr om lubrican tPresence of water in gear lubricant indicates the need for disassembl yand inspection of oil sealsseal surfaces," rings and gear ho using component s