Four winns 258 VISTA, Owner'S Manual

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Owner’s Manual Page 0 Engines, Drives and Instrumentation - Section E
Figure E6: Tachometer - Rear View
B. Speedometer
The speedometer is a water pressure sensitive unit. It
has a pick-up (pitot tube) assembly mounted on the
transom and a small plastic hose (speedo tube) that
connects it to the speedometer gauge on the dash.
See Figure E-7. The pitot tube extends below the hull.
Water strikes the tube inlet and creates positive
pressure. The faster the boat speed, the greater the
pressure, and the higher the speed indication on the
speedometer.
Figure E-7: Speedo Sender
If the pick-up becomes clogged, the speedometer will
not register. Clean the opening with a piece of wire or
disconnect the tubing and blow out the pick-up with
compressed air.
When winterizing the boat, the speedometer tubing
must be drained of water. Disconnect the speedome-
ter hose at the pick-up assembly and at the gauge
and blow through the tubing to remove the water.
With the optional GPS/Navigational package the
ability to monitor your speed is also available. Please
refer to the manufacturer’s literature for programming
the GPS unit for speed readings. This information is
included in the owner’s packet when the boat is
ordered with the navigation package.
NOTICE
Speedometers/speed indicators are not
precision instruments. The indications are
relative and should never be used for naviga-
tional purposes or similar critical situations
alone. Use other navigation systems in
conjunction with the speedometer.
NOTICE
DO NOT rely on the speed indicator when
trying to achieve a “NO WAKE” condition in a
harbor or other enclosed waterway. ALWAYS
be cognizant of the size of your waves your
boat is making and reduce throttle until you
are sure that they will not cause any damage.
You are responsible for damage caused by
the wake of your boat.
C. Temperature Gauge
The temperature gauge monitors the cooling system
of the engine. A sudden increase in the temperature
could be a signal of a blocked cooling passage or a
water pump malfunction.
NOTICE
Operation of an overheated engine can
result in engine seizure. If an unusually high
temperature reading occurs, shut the engine
off immediately.
D. Oil Pressure Gauge
The oil pressure gauge indicates the pressure in the
engine lubrication system. A drop in oil pressure is a
possible indication of oil pump or leakage problems.