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Propulsion System
3.6 Performance Issues & 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 must
be changed to prevent loss of performance and
possible engine damage.
Notice:
Before changing a propeller 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 the propeller.
Your boat was shipped with a propeller that typi-
cally provides optimum performance for your boat.
However there are factors that can aect 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
propeller, there is a good chance the propeller
is not the problem.
• The addition of heavy equipment like life rafts,
additional coolers, etc., will cause additional
load on the engine. Consequently, a dierent
propeller 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,
dierent a propeller may be required.
Notice:
Outboard engines can be damaged and
the engine warranty void if the boat is not
propped correctly. Always consult your Ev-
erglades dealer or authorized engine service
dealer when making changes to the propel-
ler or if the boat does not run near the top
recommended RPM.
Yamaha Propeller