Propeller Selection; Selection Procedure - Mercury MerCruiser Product Applications Manual

Avoid engine damage on boats with water lift mufflers. Engine must be started
immediately once water hose is turned on. Exhaust flow is required to purge water from
muffler(s). Failure to run engine will cause muffler to be filled with water, which could
potentially backup to the engine.
2. Partially open the water tap (approximately 1/2 capacity). DO NOT exceed 276 kPa
(40 psi).
Avoid engine damage from overheating. If the engine is operated above 1500 RPM
during flushing, suction created by the seawater pickup pump may collapse the flushing
water hose causing the engine to overheat.
3. Place the remote control in NEUTRAL, idle speed position and start the engine.
4. Operate the engine in NEUTRAL (out of gear) between 1200–1400 RPM.
5. Closely monitor water temperature gauge to ensure that engine does not overheat.

Propeller Selection

NOTE: A book called Everything You Need to Know About Propellers (90-86144--92)
is available from Mercury Precision Parts and Accessories. This full-color book provides
the latest in propellers, how they work, types, design and manufacturing, how to select the
proper propeller for a given application, and answers to many commonly asked questions
about boating performance.

Selection Procedure

Installed propeller must allow engine to run near the maximum rpm of the engine's
specified wide open throttle (WOT) rpm range to avoid engine damage. Using a propeller
that the causes engine to operate below the specified WOT rpm range can cause piston
and/or valve damage (even if the engine is not operated at WOT). Conversely, using a
propeller that allows engine to operate above the specified maximum rpm will cause
higher than normal wear and/or damage.
Using a propeller that does not allow the engine to operate within the specified WOT RPM
range can cause detonation or pre-ignition damage to the engine (even if the engine is not
operated at WOT). Conversely, using a propeller that allows the engine to operate above
the specified maximum RPM will cause higher than normal wear or damage. A lower pitch
or smaller diameter propeller must be used if RPM is too low, while a higher pitch or larger
diameter must be used if RPM is too high. There is a change in RPM between propeller
pitches that is generalized as follows:
90-863758060 AUGUST 2006
CAUTION
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CAUTION
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CAUTION
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Predelivery Preparation
Page 10A-3