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Troubleshooting
Engine will not start.
Various engine problems.
Refer to the engine manual accom-
panying your unit.
Unit components are frozen.
Allow to thaw. If any part of the unit
becomes frozen; excessive pres-
sure may build up in the unit which
could cause the unit to burst result-
ing in possible serious injury to the
operator or bystanders.
No discharge at nozzle when trig-
ger mechanism is squeezed.
Inadequate water supply.
Ensure hose is 3/4” (19.05mm) di-
ameter and incoming water supply
is turned on.
Low or fluctuating pressure.
Kink in water inlet hose.
Remove kink.
Kink in high pressure discharge
hose.
Replace hose.
Water inlet screen obstructed.
Remove screen, clean or replace.
Pump sucking air. (Prime eliminated)
Tighten all water intake connec-
tions. Eliminate leaks in intake line.
Not in high pressure mode.
Insert a high pressure nozzle.
Obstructed or worn spray nozzle.
Remove, clean or replace.
Damaged or obstructed valve as-
sembly on pump.
Remove, inspect, clean or replace.
Pump packing worn.
Replace packings.
Bypass valve not operating correctly.
Repair or replace.
Water is leaking from the “Heat
Dump Valve”.
Water temperature is too high.
Do not allow the unit to operate in
the bypass mode (with trigger gun
closed) for more than 3 minutes.
Defective valve.
Replace.
Oil appears milky or foamy.
Water in oil.
Change pump oil. Fill to proper
level.
Oil leaking from unit.
Do Not Use.
Contact Customer Service.
Detergent will not siphon into Low
Pressure Detergent mode.
Detergent strainer is not completely
submerged in detergent solution.
Check, submerge if necessary.
Detergent strainer is obstructed.
Inspect, clean or replace.
Detergent hose cut, obstructed.
Inspect, clean or replace.
Detergent adjusting knob on pump
turned to closed position. (If appli-
cable.)
Open adjusting knob. Refer to
“Cleaning with Detergents” pg.13.
Not in low pressure mode.
Insert 6540° (BLACK) nozzle.
Nozzle assembly is plugged.
Clean or replace.
Too many high pressure hose exten-
sions attached to the water outlet.
Use one extension maximum.
Ball and Spring in Venturi stuck.
Remove, clean or replace.
Water flows back into detergent
container.
Ball and Spring in Venturi reversed,
missing or corroded.
Remove, clean or replace.
Water flows from the nozzle when
the trigger gun is locked in the
“OFF” position.
Gun is malfunctioning.
Repair or replace.
Problem
Cause
Solution