Mercury 75 Operation Maintenance Warranty Installation Manual page 76

When boating through shallow water areas, choose a course of travel that
avoids sharp rocks and other underwater obstacles that could damage the
boat. Running the boat through these areas on full plane may be helpful as the
boat will be riding higher in the water. If the boat gets stuck on the bottom,
immediately stop the engine and move the boat to deeper water.
HOW THE JET DRIVE OPERATES
A jet driven boat has substantially different handling characteristics compared
to a propeller driven boat. It is recommended that the operator adjusts to these
characteristics by experimenting in open water at both high and low speeds.
The driveshaft driven impeller draws water up through the water intake and
then directs it at a high pressure through the water outlet nozzle to create
forward thrust. To obtain reverse, the reverse gate moves over the outlet
nozzle to direct the water in the opposite direction.
a - Water intake
b - Water outlet nozzle
c - Reverse gate
When the jet drive is in neutral, the impeller continues to rotate. However, the
reverse gate is positioned so that some of the forward thrust is diverted to
create reverse thrust. This approximate balancing of forward and reverse thrust
will minimize any boat movement. Because the impeller is always rotating and
creating thrust when the engine is running, the boat may tend to move slowly
forward or backward. This is normal for a direct‑drive jet driven boat. The
operator should be aware of this and use caution whenever the engine is
running.
OPERATION
c
a
b
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