41
2. Remove the three (3) low pressure transfer O-Rings.
WARNING:
There may be up to 75 pounds of
stored energy when separating the piston and
unloader housing from the engine adapter housing.
Remove these bolts slowly and evenly.
3. Apply a 6” C-clamp to hold the engine adapter and the
pump head together.
4. Remove the three (3) M6-1.0 x 25 cap screws that hold
the engine adapter to the piston and unloader housing, as
seen in Figure 5.5.
5. Slowly loosen the C-clamp until spring tension is released
and the components separate.
Piston & Unloader Housing Disassembly
Refer to Figure 5.6 for this disassembly, as follows:
1. Remove O-Ring from housing.
2. Remove the three (3) pistons, springs, and retainers. To
do this, grasp the piston springs and pull straight out. The
retainers will stay attached to the pistons.
3. Remove the three (3) piston oil seals.
4. Remove the thermal relief valve (if present). It is not
necessary to remove the pipe plug, if installed in place of
the thermal relief valve.
Section 5 • Small Frame Gas Pump
Portable Pressure Washer Familiarization and Troubleshooting Guide
Figure 5.6 - Piston & Unloader Housing
Item
Name
1
O-Ring
2
Piston and retainer
3
Spring
4
Thermal bypass valve or pipe plug
5
Piston and unloader housing
6
Piston oil seal
Figure 5.5 - Engine Adapter
Item
Name
1
M6-1.0 x 25 cap screw & M6 lock washer
2
Engine adapter
