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www.webasto.us
63
Webasto Product N.A., Inc.
DBW 2010/2020/300 COOLANT HEATERS
REPAIR
Figure 54:
U4814 and U4851 Circulation Pump - Exploded View
U 4846 Pump Only:
Pump is magnetically coupled
to the motor (no shaft seals to leak or replace). The
driven magnet of the pump must be free of metallic
contaminates otherwise the heater may overheat
due to loss of coolant circulation. The heater’s
overheat protection is likely to respond.
1
2
4
6
11
3
5
7
8
10
9
12
U4814
38
38
10
9
1
2
4
3
6
11
5
7
8
12
U4851
38
38
1
Screw - Impeller Housing
2
Impeller Housing
3
Nut - Impeller
4
Impeller
5
Spring Seal
6
Stationary Ceramic Seal
7
Rubber Seal
8
O-ring
9
Screw - Pump Base
10 Washer - Pump Base
11 Pump Base
12 Rubber Shaft Boot
U 4846
20
1
2
3
4
20
Figure 55:
U4846 Circulation Pump - Exploded View
1
O-ring - Impeller Housing
2
O-ring - Magnetic Drive
3
Impeller Housing
4
Screw - Impeller Housing