4646
Helm Control Systems
4.8 Trim Tabs
The trim tabs are mounted on the transom be-
low the engine mounting system. A dual rocker
switch is used to control the trim tabs. The switch
controls bow up and down movements. It also
controls starboard and port up and down move-
ments. Bow up and bow down will control the hull
planing attitude, while port and starboard up and
down provides control for the hull listing. Before
leaving the dock or loading the boat on a trailer
or forklift, make sure that the tabs are in the full
“UP” position by holding the control in the bow up
position for ten (10) seconds.
LED Indicator Switch (Optional)
If your boat is equipped with the optional LED trim
indicator switch, red LED lights next to each switch
display the position of your trim tabs. Additionally,
the switch is wired so the trim tabs automatically
retract to the “full-up” position when the ignition
switch is turned o.
The LED display indicates trim tab deection.
When one LED indicator light is lit at the top of
each display, the tabs are in the “full-up” (bow up)
position. As the tabs are lowered (bow down) ad-
ditional indicator LED lights become lit to indicate
the degree of tab plane travel. When all LED lights
are lit, the tabs are fully extended (bow down).
THE TRIM TABS CAN BE DAMAGED BY BOAT TRAILERS
IF THE BUNKS EXTEND BEYOND THE TRANSOM OR THE
BOAT IS NOT CENTERED PROPERLY. THEY CAN ALSO BE
DAMAGED BY FORK LIFTS AT DRY STACK MARINAS DURING
LIFTING. TO REDUCE THE POSSIBILITY OF DAMAGE,
ALWAYS MAKE SURE THE TABS ARE IN THE FULL UP
POSITION BEFORE LOADING YOUR BOAT ON A TRAILER
OR HAVING IT LIFTED BY A FORK LIFT.
Trim Tab Operation
Before leaving the dock, make sure that the tabs
are in the full “UP” position by holding the control
in the bow up position for ten (10) seconds.
Always establish the intended heading and cruise
speed before attempting to adjust the hull attitude
with the trim tabs. After stabilizing speed and
direction, move the trim tabs to achieve a level
side to side running attitude being careful not to
over trim.
After depressing a trim tab switch, always wait a
few seconds for the change in the trim plane to
Typical Trim Tab Switches
Trim Tab Plane & Cylinder
take eect. Avoid depressing the switch while
awaiting the trim plane reaction. By the time the
eect is noticeable the trim tab plane will have
moved too far and thus the boat will be in an
overcompensated position.
When running at a speed that will result in the
boat falling o plane, lowering the tabs slightly
bow down will improve the running angle and op-
erating eciency. Too much bow down tabs can
reduce operating eciency and cause substantial
steering and handling diculties.
Be extremely careful when operating in a following
sea. The eect of trim tabs is amplied under such
conditions. Steering and handling diculties can
result from improper trim tab usage, particularly
in a following sea. Always raise the tabs to the
full bow up position in these conditions.
When running at high speeds be sure that the
tabs are in the full “UP” position. Only enough
To Next Page
Loading...