Impeller Removal And Installation - Mercury 25 Jet 4-Stroke Manual

As the blades wear, shims located in the stack outside of the
impeller can be transferred behind the impeller. This will move the
impeller further down into the tapered liner to reduce the clearance.
a - Shims
b - Clearance between impeller edge and liner
Check the impeller clearance by sliding a feeler gauge through the
intake grate and measure the clearance between the impeller edge
and liner. If adjustment is required, refer to Impeller Removal and
Installation.

Impeller Removal and Installation

If the driveshaft is rotated, there is the possibility that the engine
will crank over and start. To prevent this type of accidental engine
starting and possible serious injury caused from being struck by
a rotating impeller, always turn the ignition key or lanyard stop
switch to the "OFF" position and remove the spark plug leads
from the spark plugs while servicing the impeller.
MAINTENANCE
WARNING
!
71
b
a
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