Servicing The Stator, Impeller, And Wear Ring; Disassembly - Mercury 200 OptiMax Jet Drive Service Manual

The jet pump operates by drawing water into a housing forward of the impeller. The water is pressurized within the specially
designed housing and then directed to the rear to provide thrust and motion.
b
The jet pump is equipped with a steerable nozzle (rudder) at the aft end of the pump housing that directs the thrust of water. The
jet of water can be directed right or left when the operator turns the steering wheel in the respective direction. When the operator
turns the steering wheel to the right, for example, the nozzle turns to the right and the jet force from the nozzle pushes the stern
of the boat to the left causing the bow of the boat to turn right. Forward, reverse drive, and the neutral position are achieved by
the position of a reverse gate located just aft of the nozzle.
Forward drive has the reverse gate clearing the nozzle to allow all the water to be directed straight back. Reverse drive has the
reverse gate covering the entire opening enough to divert the water forward. Neutral position has the reverse gate covering 75
percent of the nozzle to direct the water stream forward and downward, as well as backward. The shift position is controlled at
the control box in the boat.
a

Servicing the Stator, Impeller, and Wear Ring

Disassembly

1. Disconnect spark plug leads from spark plugs.
90-8M0050731 MAY 2011
c a
a - Forward motion
b - Water thrust
c - Reverse gate ‑ forward position
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a - Reverse gate ‑ reverse position
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Pump Unit
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