Four winns FUNSHIP - Control.listing; Induce.planing.&.Controlling.trim.angle

Owner’s Manual Page 54Engines and Instrumentation - Section E
B. Induce Planing & Controlling Trim Angle
Trim tabs can also be used to facilitate faster planing
and allow better control of the running angle.
Before accelerating and trying to gain plane, press
both upper trim tab switches. This will cause both
trim tabs to move downward and force the bow down
when running. This can also be used when running
the boat with a heavy load aboard.
Moving the trim tabs downward will increase the lift
and the boat will achieve plane faster, or stay on
plane at a lower engine and boat speed.
After gaining plane and establishing cruising speed,
pressing both lower trim tab switches will cause both
trim tabs to move upward and will allow the bow
to rise. This should be used to adjust the running
attitude of the boat to decrease the drag at cruising
speed or above, or when running in a following sea.
When running at an engine speed that results in the
boat falling off plane or causes the boat to plane
inefciently,loweringbothtabsslightly(bowdown)
will improve the running angle and improve operating
efciency.
Optimumefciencyisobtainedwhenoperatingata
3 to 5 degree running angle. Utilizing too much “Bow
Down”trimtabcanreduceoperatingefciencyand
causesubstantialsteeringandhandlingdifculties.
Be extremely careful when running in a following sea.
Theeffectoftrimtabsisampliedundersuchcondi-
tions.Steeringandhandlingdifcultiescanresult
from improper trim tab usage, especially in a follow-
ing sea. If unsure of proper trim tab positioning,
raise the trim tabs to the full-up position.
When running at high engine speeds, be sure
the trim tabs are in the full up position. Trim tab
action should be only enough to compensate
for any listing. Trim tab adjustments at high
speeds are extremely critical. Be prepared to
slow down should handling difculties arise.
When running in a displacement (very slow speed)
mode,betterefciencywillbeobtainedwiththetrim
tabs in the full-up position.
Before leaving the dock and utilizing the trim tabs,
e
nsure the trim tabs are in the full up position. Press
both lower halves of the trim tab switches and hold
(for approximately 10 seconds) until the tabs are full up.
A. Control Listing
Wind, loading and many other factors can result in the
boat tilting or leaning towards one side while running.
This is called listing and can be negated using trim
tabs.
Pressing the lower port trim tab switch will move the
starboard trim tab upward. This will result in the port
bow of the boat being allowed to rise.
Pressing the lower starboard trim tab switch will cause
the port trim tab to move upward and will result in the
starboard bow being allowed to rise.
Pressing the upper port trim tab switch will cause the
starboard trim tab to move downward and will force
the port bow downward.
Pressing the upper starboard trim tab switch will cause
the port trim tab to move downward and will force the
starboard bow downward.
Always establish your intended heading and attain
desired cruising speed before trying to adjust running
attitude (using the trim tabs).
Always press the trim tab switches in short one
(1) second bursts. If pressed too long, you can
overcompensate, and potentially lose control.
DO NOT try to correct the situation by pressing
the other upper trim tab switch. Instead, raise
the tab slightly by pressing the appropriate
lower half of the trim tab switch.
After stabilization of speed and direction, press the
upper half of the appropriate trim tab switch to achieve
a level side to side running attitude. Be sure to press
the correct trim tab switch to obtain the desired result.
After pressing a trim tab switch, always wait and allow
time for the change in trim tab position to take effect.
DO NOT continue to press the trim tab switch while
awaiting trim tab reaction. By the time the effect is
noted, the trim tab will move too far and thus overcom-
pensate.