Propeller Selection - Mercury HP 500 EFI Bravo XR/XZ/III User Manual

CONDITIONS AFFECTING
CA294

Propeller Selection

IMPORTANT: Installed propeller must allow engine to run at its
specified maximum wide-open-throttle rpm. Use an accurate
service tachometer to verify engine operating rpm.
It is the responsibility of the boat manufacturer and/or the selling
dealer to equip the power package with the correct propeller(s).
Specified engine wide-open-throttle (WOT) and operating rpm range
are listed in "SPECIFICATIONS".
IMPORTANT: All MerCruiser Hi-Performance engines have a
rpm rev-limiter that is set to an upper (or limited) rpm amount.
This limit is slightly above the normal operating range of the en-
gine and is designed to help prevent damage from excessive
engine rpm. Once the rpm drops into the recommended operat-
ing rpm range normal engine operation resumes.
Select a propeller that allows the engine to operate in the upper half
of the recommended full throttle rpm range with the boat normally
loaded (Refer to specifications).
If full throttle operation is below the recommended range, the
propeller must be changed to prevent loss of performance and
possible engine damage. On the other hand, operating an engine
above the recommended operating rpm range will cause higher than
normal wear and/or damage. Generally, there is a 200-300 rpm
change between propeller pitches.
Rpm loss may require a change to a lower pitch propeller due
to the following conditions:
•
Warmer weather and greater humidity.
•
Operating in a higher elevation.
•
Operating with a damaged propeller or dirty boat bottom.
•
Operating with increased load (additional passengers, pulling ski-
ers, etc.).
For better acceleration, such as is needed for water skiing, use the
next lower pitch propeller. However, do not operate at full throttle (or
above the recommended rpm range) when using the lower pitch
propeller but not pulling skiers.
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OPERATION
500 EFI Bravo