Yamaha F90 - Changing Gear Oil

Maintenance
88
EMU47100
Changing gear oil
WARNING
EWM00801
z Be sure the outboard motor is securely
fastened to the transom or a stable
stand. You could be severely injured if
the outboard motor falls on you.
z Never get under the lower unit while it is
tilted, even when the tilt support lever or
knob is locked. Severe injury could oc-
cur if the outboard motor accidentally
falls.
1. Tilt the outboard motor so that the gear
oil drain screw is at the lowest point pos-
sible.
2. Place a suitable container under the gear
case.
3. Remove the gear oil drain screw and
gasket. The screw is magnetic so a small
quantity of metal particles on the end of
the screw is normal. Simply remove
them. NOTICE: If there is an excessive
quantity of metal particles on the
magnetic gear oil drain screw, this
can indicate lower unit problem. Con-
sult your Yamaha dealer.
[ECM01901]
TIP:
Always use new gaskets. Do not reuse the re-
moved gaskets.
4. Remove the oil level plug and gasket to
allow the oil to drain completely.
NOTICE: Check the used gear oil after
it has been drained. If the gear oil is
milky or contains water or a large
amount of metal particles, the gear
case may be damaged. Have a
Yamaha dealer check and repair the
outboard motor.
[ECM00714]
TIP:
For disposal of used oil, consult your Yamaha
dealer.
5. Put the outboard motor in a vertical posi-
tion. Using a flexible or pressurized filling
device, inject the gear oil into the gear oil
drain screw hole.
1. Gear oil drain screw
2. Oil level plug
1
2
ZMU08120
1. Gasket
2. Oil level plug
Recommended gear oil:
Yamalube Marine Gearcase Lube or
Hypoid gear oil
Recommended gear oil grade:
SAE 90 API GL-4 / SAE 80W API GL-
5 / SAE 90 API GL-5
Gear oil quantity:
0.760 L (0.803 US qt, 0.669 Imp.qt)
1
2
ZMU08121
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