Mercury 40 jet fourstroke User Manual page 80

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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