Alamarin Jet AJ 160, Operation And Maintenance Manual

Page: 30 / 40

Operation and Maintenance Manual
3030
Version 1.5
30
Figure 4.3-1
The size marking of the impeller can be found both at the front and rear end (figure 4.3-
1). It can be seen through the inspection hatch and by removing the stator.
Marking showing the
size of the impeller
The condition of the front edge of the
impeller blades is important. A damaged
front edge causes cavitation.
The front edge can be repaired by
carefully hammering the marks caused
by bigger stones and grinding them
smooth. The front edge must not be
sharpened, it must be left about 2mm
thick and rounded
r = 1 mm.
Figure 4.3-2
You can also return the impeller to the factory for checking and repairing.
If you suspect that there is a malfunction in the impeller, do as follows:
1. Shut down the engine and open the inspection hatch.
2. Check that nothing is blocking the intake duct.
3. Check the impeller visually. Notice especially the gap between the outer
edge of the blade and the duct wall.
r