Alamarin Jet AJ 340, Руководство по эксплуатации и обслуживанию

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Maintenance
Operation and maintenance manual
26 KHO/340/EN/1.0.0.
Figure 23. Oil reservoir cover
4. Reattach the six cover screws (figure 21).
4.7. Raw water cooling
The jet does not have a raw water cooling connection for the engine.
4.8. Impeller
The amount of power required by the impeller depends on the pitch, length
and number of blades.
Depending on driving conditions, the impeller will wear down, causing a
gap to develop between the duct wall and the tip of the impeller blade. The
gap should be as small as possible to achieve maximum efficiency. (Factory
installation gap is 0.5 mm (approx. 0.008")). When the gap expands too much,
the jet's performance decreases.
The impeller usually wears on the outer edge of the blades. The impeller
operates in a cone-shaped space and its position can be adjusted in the
direction of the shaft in accordance with the blade wear.
By adjusting the impeller, its operating life can be prolonged considerably. The
adjustment of the impeller should be done whenever it is necessary, but checks
must be carried out at least once a year. The impeller is adjusted by removing
the impeller and then reinstalling it.
4.8.1. Checking the impeller
The condition of the front edge of the impeller blades is important. A damaged
front edge causes cavitation.
WARNING!
The impeller blade edges can be sharp and cut your hands.
Protect your hands with protective gloves before you remove
the impeller.
The front edge can be repaired by carefully hammering the marks caused
by bigger stones and grinding them smooth. The front edge must also be
sharpened, not sharp enough to cut, but so that it is no thicker than 1 mm
(approx. 0.04").
You can also return the impeller to the factory for checking and repairing.