90
On units so equipped, inspect the three (3) lock rings and
the three (3) spring retainers; replace if damaged.
Inspect the three (3) piston springs. Ends must be closed
and ground square. Check spring free length and load length
as follows, referring to Figure 7.27:
1. Free length should be 62.57 mm (2.463”).
2. Apply a force of 51.0 to 56.4 pounds (227.2 to 251.1
Newtons). At the stated load, spring length should be
39.8 mm (1.567”).
Replace any spring that is damaged or broken. replace spring
if free length or load length is not as stated.
Unloader-Pressure Regulator Valve
Refer to Figure 7.11, seen earlier. Replace any damaged or
defective parts as necessary.
Section 7 • Large Frame Pump
Portable Pressure Washer Familiarization and Troubleshooting Guide
Item
Name
1
Free length
2
Load length
Figure 7.27 — Piston Return Spring
