Mercury 25 Jet FourStroke, Руководство по эксплуатации, техническому обслуживанию и установке

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• Difficulty getting the boat on plane
• An increase in engine RPM at wide‑open throttle
IMPORTANT: Do not sharpen or alter the top side lifting angle.
Check the impeller blades occasionally for damage. Use a flat file to sharpen
the leading edges. Sharpen to a 0.8 mm (1/32 in.) radius by removing material
from bottom side only.
a - Leading edge
b - Top side lifting angle
Impeller Clearance Adjustment
The impeller should be adjusted so there is approximately 0.8 mm (0.03 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 (0.03 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 - 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.
a
b
29079
a
b
29080
MAINTENANCE
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