Scout Boats 245 Abaco, Руководство пользователя

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1.5 Propellers
The propellers convert the engine’s power into
thrust. They come in a variety of styles, diam-
eters and pitches. All boats powered by Yamaha
engines are equipped with Yamaha “Saltwater
Series” propellers. The one that will best suit the
needs of your boat will depend somewhat on your
application and expected average load. Propel-
ler sizes are identified by two numbers stamped
on the prop in sequence. The 1st number in the
sequence (example 14
”
x 21”) is the diameter of
the propeller, and the 2nd number is the pitch.
Pitch is the theoretical distance traveled by the
propeller in each revolution.
Always repair or replace a propeller immediately if
it has been damaged. A damaged and therefore
out of balance propeller can cause vibration that
can be felt in the boat and could damage the en-
gine gear assembly. Refer to the engine owner’s
manual for information on propeller removal and
installation.
1.6 Performance Issues and Propellers
It is extremely important that the boat is propped
to run at or very near the recommended top RPM
with an average load. If the top RPM is above
or below the recommend range, the propeller or
propellers must be changed to prevent loss of
performance and possible engine damage.
Dual engine boats are equipped from the factory
with counter rotating engines that are mounted
to achieve quicker planning and optimum per-
formance. Therefore, the left rotation engine is
mounted on the port side of the transom and the
right rotation engine is mounted on the starboard
side. You should make sure that each propeller
matches the rotation of the engine.
Notice:
Before changing propellers to correct boat
performance problems, be sure other factors
such as engine tuning, bottom and running
gear growth, etc. are not the source of per-
formance changes. Always be sure the load
conditions are those normally experienced
before changing propellers.
Your boat was shipped with propellers that typi-
cally provide optimum performance for your boat.
However there are factors that can affect perfor-
mance and propeller requirements.
Some are as follows:
• You should be sure the load conditions are
those normally experienced. If the boat ran
in the required RPM range when it was new
and you have not added any additional gear
or heavy equipment and have not damaged
the propellers, there is a good chance the
propellers are not the problem.
• The addition of heavy equipment like a tower,
life rafts, additional coolers, etc., will cause
additional load on the engines. Consequently,
different propellers may be required.
• Boats operated at high altitudes (above 2000
feet). Engines operated at high altitudes will
not be able to develop as much horsepower
as they do at or near sea level. Consequently,
different propellers may be required.
Notice:
Outboard engines can be damaged and the
warranty void if the boat is not propped
correctly. Always consult your Scout dealer
or authorized engine service dealer when
making changes to the propellers or if the
boat does not run near the top recommended
RPM.
Yamaha Saltwater Series Propeller