Tilting Up And Down - Yamaha F300A Owner's Manual

Operation
Bow Up
Too much trim-out puts the bow of the boat
too high in the water. Performance and econ-
omy are decreased because the hull of the
boat is pushing the water and there is more
air drag. Excessive trim-out can also cause
the propeller to ventilate, which reduces per-
formance further, and the boat may "por-
poise" (hop in the water), which could throw
the operator and passengers overboard.
Bow Down
Too much trim-in causes the boat to "plow"
through the water, decreasing fuel economy
and making it hard to increase speed. Oper-
ating with excessive trim-in at higher speeds
also makes the boat unstable. Resistance at
the bow is greatly increased, heightening the
danger of "bow steering" and making opera-
tion difficult and dangerous.
71
TIP:
Depending on the type of boat, the outboard
motor trim angle may have little effect on the
trim of the boat when operating.
EMU27944

Tilting up and down

If the engine will be stopped for some time or
if the boat is moored in shallows, the out-
board motor should be tilted up to protect the
propeller and lower case from damage by
collision with obstructions, and also to re-
duce salt corrosion.
EWM01541
WARNING
Be sure all people are clear of the out-
board motor when tilting up and down.
Body parts can be crushed between the
motor and the clamp bracket when the
motor is trimmed or tilted.
ECM00991
NOTICE
Before tilting the outboard motor, fol-
G
low the procedure under "Stopping en-
gine" in this chapter. Never tilt the
outboard motor while the engine is run-
ning. Severe damage from overheating
can result.
To prevent the cooling water passages
G
from becoming frozen when the ambi-
ent temperature is 5°C or below, tilt the
outboard motor up after it has been