Yanmar BY series, Service Manual

Page: 179 / 275

COOLING SYSTEM
7-20
BY Service Manual
Repair
Seawater Pump
Inspect / Replace Impeller
Figure 7-22
1. Drain the seawater circuit by loosening the
drain cock (Figure 7-22, (1)) in the outlet pipe.
2. Remove the seawater pump belt. See Replace
Seawater Pump Belt on page 7-21.
Figure 7-23
3. Remove four screws and remove the water
pump cover, belt pulley, and shaft as an
assembly
(Figure 7-23, (1)) .
4. Remove the impeller (Figure 7-23, (2)) from the
housing.
5. Inspect the impeller for cracks, broken vanes, or
excessive wear. Replace as necessary.
6. Inspect the housing and cover for excessive
wear.
Figure 7-24
Note: When installing the new impeller, rotate
the impeller clockwise to bend the vanes
in the direction of rotation
(Figure 7-24) .
7. Install a new O-ring (Figure 7-24, (1)) and hold
it in the groove using petroleum jelly.
8. Install the shaft, cover and pulley assembly.
Install and tighten four screws.
9. Install the seawater pump belt. See Replace
Seawater Pump Belt on page 7-21.
Remove and Install Seawater Pump
1. Disconnect battery negative (-) cable.
2. Remove seawater pump belt. See Replace
Seawater Pump Belt on page 7-21.
000 3 655
(1)
000 3 657
(1)
(2)
000 3 65 8
(1)