63
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 6.19:
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).
3. At the stated load, spring length should be 39.8 mm
(1.567”).
4. Replace all three (3) springs as a set if any one spring is
damaged or broken. Replace the springs as a set if the
free length or load length of any one spring does not
meet specifications.
High Pressure Outlet/Chemical Injection Assembly
Referring to Figure 6.20, inspect the chemical injection and
unloader components for signs of damage, obstructions, or
wear. Replace any damaged or defective parts as necessary.
Section 6 • Medium Frame Pump
Portable Pressure Washer Familiarization and Troubleshooting Guide
Figure 6.20 — High Pressure Outlet/Chemical Inject Assembly
Item
Name
1
Setscrew, M6-1.0 x 8mm
2
Unloader handle
3
Unloader spindle assembly
4
Chemical injection spring
5
Chemical injection fitting
6
Check ball
7
Trapped line pressure seat
8
Spring
9
Venturi assembly
10
Trapped line pressure piston assembly
11
Unloader ball
12
Ball seat assembly
13
Head
14
Unloader spring
15
Plastic cap
Item
Name
1
Free length
2
Load length
Figure 6.19 — Piston Return Spring
