Unloader (pressure)
produces low flow and
normal pressure
Unloader adjusted too low
If the unloader is diverting flow to bypass it may be adjusted too low, readjust as necessary.
Spray nozzle to large
Ensure the proper nozzle is installed on system.
Internal nozzle erosion
The number of hours of usage can give you a clue to the extent of the ware. If in doubt, change
Insufficient pump pressure
Check pump seals and packings and tighten drive belts.
Unloader (flow) produces
low flow & normal pressure
Unloader adjusted too low
If unloader is diverting flow to bypass, readjust using the pressure gauge.
Nozzle too large
Ensure the proper sized nozzle is being used.
Unloader (pressure) leaks
from main spring or
adjusting bolt
Shaft O-ring in valve body warn
Check O-rings for ware or damage and replace as necessary.
Unloader (flow) pressure
increases when trigger
released
Unloader piston stuck or frozen
Check unloader shaft for proper action. Unstick piston and shaft or replace unloader.
Bypass port clogged or restricted
Ensure that unloader bypass port is not clogged
Excessive tension on main spring If tension is incorrect, adjust or replace as necessary.
Unloader (flow) leaks water
around adjusting bolt
Sleeve O-ring worn
Check O-rings for ware or damage and replace as necessary.
