10
Problems That Cause Water Leaks
A. Thermal Relief Valve
The thermal relief valve (38) protects the pump from hot water temperatures in bypass mode.
If the thermal relief valve is damaged or does not reset, there will be a continual leak.
Check thermal relief valve (38).
Note:
It is normal for the thermal relief valve to release hot water, if the pump continues to run in the
bypass mode for an extended amount of time, which causes the water circulating within the
pump to reach a temperature level that will cause internal damage. Once the valve releases
the hot water, it will automatically reset itself.
B. weep holes – High-Pressure Seals
Water leaking from the weep holes (15) can indicate a leak in the high-pressure seals.
Check seals for damage.
C. weep holes – Low-Pressure Seals
Water leaking from the weep holes (15) can indicate a leak in the low-pressure seals (39).
Check the seals for damage.
12...Swash
10...Swash assembly
9...Forward O ring
8...Pump shaft seal
7...Oil bath housing
4...O-ring
3...Oil reservoir
2...Oil filter
1...Oil reservoir vent cap
31...Detergent check valve
32...O-ring
33...Ball bearing
34...Spring
17...Pressure/volume control knob
18...Bypass valve
19...Bushing
30...Water inlet filter
25...Low pressure check valve basket (3)
56...Water outlet bolt (4)
13...Piston (3)
46...High pressure valve seat (3)
38...Thermal relief valve
20...High pressure seal (3)
6...Oil drain
plug
39...Low pressure oil seal (3)
40...Seal retaining ring (3)
41...Bushing seal (3)
42...Bushing (3)
45...High pressure valve slide
55...Safety relief valve
54...Ball bearing
53...Ball bearing seat
52...Spring
51...Pump head bolt (4)
50...High pressure valve cap (3)
37...Retainer nut
47...High pressure valve plate (3)
48...High pressure valve spring (3)
49...High pressure valve basket (3)
26...Low pressure check valve spring (3)
27...Low pressure check valve plate (3)
28...Low pressure check valve seat (3)
44...Piston guide retaining screw (2)
22...Water outlet
43...Scraper ring (3)
35...Detergent tube
36...Detergent filter
5...Oil drain
plug ring
11...Swash plate ball bearings
29...Water inlet
23...Non-return check valve
24...Nozzle insert
21...Pump head
14...Piston spring (3)
16...Piston housing
15...Weep holes (3)
SECTION 2 / WATER LEAKS
Pump 785 9/28/01 3:06 PM Page 10
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For Karcher Pressure Washer Parts Call 606-678-9623 or 606-561-4983
