Troubleshooting

Problem

Cause

Solution

 

 

 

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-

Inadequate water supply.

Ensure hose is 3/4” (19.05mm) di-

ger mechanism is squeezed.

 

ameter and incoming water supply

 

 

is turned on.

 

 

 

Low or fluctuating pressure.

Kink in water inlet hose.

Remove kink.

 

 

 

 

Kink in high pressure discharge

Replace hose.

 

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-

Remove, inspect, clean or replace.

 

sembly on pump.

 

 

 

 

 

Pump packing worn.

Replace packings.

 

 

 

 

Bypass valve not operating correctly.

Repair or replace.

 

 

 

Water is leaking from the “Heat

Water temperature is too high.

Do not allow the unit to operate in

Dump Valve”.

 

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

Detergent strainer is not completely

Check, submerge if necessary.

Pressure Detergent mode.

submerged in detergent solution.

 

 

Detergent strainer is obstructed.

Inspect, clean or replace.

 

 

 

 

Detergent hose cut, obstructed.

Inspect, clean or replace.

 

 

 

 

Detergent adjusting knob on pump

Open adjusting knob. Refer to

 

turned to closed position. (If appli-

“Cleaning with Detergents” pg.13.

 

cable.)

 

 

 

 

 

Not in low pressure mode.

Insert 6540° (BLACK) nozzle.

 

 

 

 

Nozzle assembly is plugged.

Clean or replace.

 

Too many high pressure hose exten-

Use one extension maximum.

 

sions attached to the water outlet.

 

 

 

 

 

Ball and Spring in Venturi stuck.

Remove, clean or replace.

 

 

 

Water flows back into detergent

Ball and Spring in Venturi reversed,

Remove, clean or replace.

container.

missing or corroded.

 

 

 

 

Water flows from the nozzle when

Gun is malfunctioning.

Repair or replace.

the trigger gun is locked in the

 

 

“OFF” position.

 

 

 

 

 

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Graco 4043BD, 4035BD important safety instructions Troubleshooting, Problem, Cause, Solution