If the engine is trimmed “DOWN,” speed drops, the efficiency and fuel economy
decrease and the craft may not handle correctly. Trim “DOWN” provides better
acceleration from a standstill because it will force the bow down. If the engine is
trimmed “UP,” steering torque can increase and the propeller can cavitate (spin and
not grab). This can make the craft difficult to get on plane and cause the craft to
porpoise.
Figure 3-16
TRIM TABS
The electric/hydraulic trim tabs are adjusted at the helm. Water is deflected and
redirected as the trim tabs move through the water and they are raised and lowered.
This change in water flow creates upward pressure under the tabs and raises the
stern. When the stern raises, the bow is lowered.
Trim tabs act in the same way as the power trim on the drive unit. This allows
compensation for uneven loads by trimming up one side or the other. They also
assist in providing maximum control of the hull in different water and load conditions.
If used properly, trim tabs can greatly improve performance and fuel efficiency. The
proper use of trim tabs requires a basic understanding of trim tab operation and
some practice in calm water.
Your trim tab control has two (2) two-position, momentary switches labeled Bow
Down and Bow Up:
•
Depress front-starboard button to move trim plane on port side downward.
This moves starboard bow downward when boat is planing.
•
Depress front-port button to move trim plane on starboard side downward.
This moves port bow downward when boat is planing.
CORRECT
IN TOO FAR
OUT TOO FAR
CRO_012
UP
TRIM
DN
UP
TRIM
DN
UP
TRIM
DN
Section 3
3-38
Owner’s/Operator’s Manual
Crownline_OM_sec3.qxp 11/13/2006 8:33 AM Page 3-38
