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3.4 Impeller Clearance Adjustment
The impeller should be adjusted so there is approximately 0.8 mm (0.031 in.) clearance between the
impeller edge and liner. Operating the jet drive in waters that contain sand and gravel can cause wear to the
impeller blades, and the clearance will start to exceed 0.8 mm (0.031 in.).
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
b
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 3.1 Impeller Removal and
Installation.
