Mercury 250 XS OptiMax, Operation, Maintenance & Installation Manual, Page: 80 / 131

Gearcase Lubricant
CHECKING/REFILLING GEARCASE LUBRICANT
a - Sport Master gearcase (vertical operating position)
b - Fleet Master gearcase (vertical operating position)
c - Vent hole
d - Vent plug and sealing washer
e - Fill/drain hole
f - Fill/drain plug
Tube Ref
No.
Description Where Used Part No.
SAE 85W90 Mercury
Racing Gear Oil
Gearcase 8M0078015
1. Place the outboard in a vertical operating position.
2. Remove the vent plug (upper plug) and sealing washer.
3. Remove the fill/drain plug (lower plug).
4. Quickly place lubricant tube into the fill hole.
5. Slowly add lubricant until it flows from the (upper) vent hole.
6. Stop adding lubricant. Install the (upper) vent plug and sealing washer
before removing the lubricant tube.
IMPORTANT: Replace sealing washers if damaged.
NOTE: Examine the magnetic fill/drain plug for metal particles. A small amount
of metal filings or fine metal particles indicates normal gear wear. An
excessive amount of metal filings or larger particles (chips) should be checked
by an authorized dealer.
7. Remove lubricant tube and reinstall cleaned (lower) fill/drain plug and
sealing washer.
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2743
MAINTENANCE
70
eng