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CD751
Propeller Selection
IMPORTANT: Installed propeller must allow engine to run at the upper end of the specified throttle oper-
ating revolutions per minute (rpm) range, with a normal load aboard the boat. 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 below and
in Specifications.
IMPORTANT: The engines covered in this manual, depending upon the model, are equipped with either
a governor or a device that limits engine rpm. Be sure that propeller being used does not allow engine
to run against the governor or limiter, as a significant loss in performance will result.
Engine Rpm Limits
MCM Model Engine Specified Operating Rpm Range
Rpm Governor or Limiter Setting
(Begins At: )
D1.7L DTI 4000 - 4400 4400
Select a propeller that will allow the engine power package to operate at or near the top end of the recommended
wide-open-throttle operating rpm range with a normal load. High rpm, caused by an excessive trim angle, should
not be used in determining correct propeller selection.
If full throttle operation is below the specified range, the propeller must be changed to prevent loss of perfor-
mance and possible engine damage. On the other hand, operating an engine above the specified operating rpm
range will cause higher than normal wear and/or damage.
After initial propeller selection, the following common problems may require that the propeller be changed to a
lower pitch:
• Warmer weather and greater humidity cause an rpm loss.
• Operating in a higher elevation causes an rpm loss.
• Operating with a damaged propeller or dirty boat bottom causes an rpm loss.
• Operating with increased load (additional passengers, pulling skiers, etc.).
For better acceleration, such as is needed for water skiing, use the next lower pitch propeller. However, do not
operate at full throttle when using the lower pitch propeller but not pulling skiers.
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