Four winns 258 VISTA, Owner'S Manual

Page: 208 / 259

Owner’s Manual Page 0 Pre-Launch and Underway - Section T
T - 6 ACCELERATION
Before accelerating to bring you boat on plane,
be sure that the area in front of your boat is
clear. The bow will rise out of the water
momentarily before you plane and may
temporarily obstruct your vision.
If you have never had your boat on plane before,
choose a calm day for your first on plane experience.
Never boat beyond your ability and experience.
Before bringing your boat “on plane”, check the entire
area to make sure you have a clear, safe path. As you
throttle up to accelerate, your boat will increase its
angle of trim, causing the bow to ride high. From a
maximum angle, the boat will level out to its planing
attitude with continued acceleration. This maximum
angle is known as the “hump”. Because visibility,
handling, and performance are reduced, it is advisable
to get “over the hump” as soon as possible. A few
seconds at full throttle should get the boat over the
hump and into its planing attitude.
After getting over the hump, accelerate until reaching a
comfortable plane, then throttle down to cruising speed.
This also will provide for better fuel efficiency.
T - 7 TRIMMING YOUR BOAT
A. Trim Tabs
Trim tabs are used to add lift to the boat’s stern,
thereby changing the boat’s attitude (see Figure S1).
This lift can help the boat get on plane faster and
remain on plane at slower speeds than if no tabs were
used. Used independently, tabs can also correct listing
conditions caused by crosswinds, unbalanced loading
and quartering seas. Trimming your boat properly
involves two separate procedures, trimming or tilting
the lower unit (stern drives) and setting the trim tabs.
When you are sitting dead in the water, your drive
should be down and the trim tab switches are in the
BOW UP position. Accelerate until you get onto plane.
At this point your boat will be plowing through the water
with the bow down too far. Trim the lower unit up
slightly until the bow comes up. If you trim the lower
unit out too far, your boat will porpoise or the propeller
will cavitate, and the bow will slam up and down on the
water. Your boat is trimmed correctly when it is just
short of porpoising or propeller cavitation, under ideal
running conditions.
Trim your boat to compensate for seas, winds, or
uneven loads.
Head Seas Trim drives in more than
usual. Use tabs to keep
bow down and go at a
slower speed.
Following Seas To prevent taking seawater
The bow, trim drives out and
keep tabs up to keep bow
down
Listing Due to
Quartering Seas,
Beam Wind, or
Uneven Load
Use tabs independently to
adjust for list. If listing to star-
board, press port bow down
switch. If listing to port, press
starboard bow down switch.
Remember that most boats react very slowly to trim
tabs. Often boat owners do not give trim tabs time to
work. Press the trim tab switches for only one second
at a time and then allow some time for the boat to
react. If the boat is still listing after a minute or two,
press the trim tab switch again for a one second
interval. The labels on the trim tab switches indicate
what you want your boat to do, not what you want the
tabs to do.
It is a good idea to take your boat out onto open
water shortly after you get it and experiment with the
trim tabs. After you get your boat onto plane, set the
tabs in various positions and note how your boat
reacts. This will give you a feel for how the trim tabs
work.
It is possible to extend the cylinder life expectancy on
your trim tabs. To do this, keep the cylinders retract-
ed while at dockside. Press both trim tab controls
down until tabs reach their full up position.