OXE OXE-150 HP, Installation Manual

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OXE 150/200 HP INSTALLATION MANUAL
PROPELLER SELECTION
The ideal propeller for a boat is one that provides maximum performance in
relation to boat speed and fuel consumption when the engine speed is at full
throttle operating range, e.g. about 5000 to 6000 rpm.
Water testing with various propeller designs and sizes is the best method of
propeller selection. The type, size, and design of the propeller have direct impact
on boat acceleration, top speed, fuel economy, and even engine life.
An incorrect choice could reduce engine life, affect boat performance or or cause
serious damage to the engine.
For a greater operating load, a smaller pitch propeller is more suitable as it
enables the correct engine speed to be maintained. A larger pitch propeller is more
suitable for a smaller operating load.
NOTE! If the propeller blades have too much pitch, the engine will operate below
the normal range at full throttle. Engine damage could occur due to the power
loss.
If the propeller blades have too little pitch the engine will operate above its normal
range and damage from over-speeding can occur.
For best all-round performance, select a propeller that allows the engine to
operate in the upper half of the recommended full throttle speed range with the
boat normally loaded. Check full throttle speed, using an accurate tachometer, with
engine trimmed out to a balanced steering condition (steering effort equal in both
directions) without causing the propeller to brake loose.
PROPELLER SELECTION