Adjusting Boat Trim - Yamaha F6A Owner's Manual

NOTE:
Stay within the trim operating angle when
trimming the outboard motor using the power
tilt system.
To raise the bow ("trim-out"), tilt the engine up.
To lower the bow ("trim-in"), tilt the engine
down.
Make test runs with the trim set to different an-
gles to find the position that works best for
your boat and operating conditions.
EMU27911

Adjusting boat trim

When the boat is on plane, a bow-up attitude
results in less drag, greater stability and effi-
ciency. This is generally when the keel line of
the boat is up about 3 to 5 degrees. With the
bow up, the boat may have a greater tenden-
cy to steer to one side or the other. Compen-
sate for this as you steer. The trim tab can
also be adjusted to help offset this effect.
When the bow of the boat is down, it is easier
to accelerate from a standing start onto plane.
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 perfor-
mance further, and the boat may "porpoise"
(hop in the water), which could throw the op-
erator 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. Operat-
ing with excessive trim-in at higher speeds
also makes the boat unstable. Resistance at
Operation
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