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9.801-760.0 Service Manual, Catch Up
PRESSURE
W
ASHER
SER
VICE MANU
AL
22
TROUBLESHOOTING
For Models: HD 3.0/27 G, HD 3.5/35 G, HD 4.0/40 G, HD 4.0/40Ge
PROBLEM
POSSIBLE CAUSE
SOLUTION
LOW OPERATING
PRESSURE
Insufficient water supply. Closed
faucet. Inlet hose kinked
Use larger garden hose; clean inlet water
screen. Open faucet.
Clogged inlet hose strainer
Check plumbing system for leaks. Retape
leaks with teflon tape.
Faulty or mis-adjusted unloader
valve
Adjust unloader for proper pressure. Install
repair kit when needed. Call local distributor.
Worn packing in pump
Call Dealer Customer Support.
Machine has been stored in freez-
ing temperatures
Thaw out machine completely, including
hose, spray gun and wand.
Slow engine RPM
Call local distributor.
FLUCTUATING
PRESSURE
Worn or dirty pump valves
Call local distributor.
Nozzle is obstructed
Blow out or remove debris with fine needle.
Pump sucking air, inlet hose
leaking
Check that all hoses and fittings are airtight.
Turn off machine and trigger spray gun until
a steady flow of water emerges through the
nozzle.
Insufficient water supply
Turn water on full force. Check garden hose
for kinks, leaks or blockage.
PRESSURE LOW
AFTER PERIOD OF
NORMAL USE
Nozzle worn
Replace nozzle.
Unloader valve worn
Replace unloader valve.
ENGINE WILL NOT
START OR STOPS
WHILE OPERATING
Low oil shutdown
Fill engine with oil.
Out of gas
Fill fuel tank.
Water in gasoline
Drain gas tank; fill with clean fuel.
ENGINE IS
OVERLOADED
Nozzle partially blocked
Clean nozzle.
Excessive pressure from high
engine RPM
Adjust engine throttle to lower RPM.
WATER OR OIL
LEAKING FROM
BOTTOM OF PUMP
A small amount of leaking is
normal
If excessive leaking occurs, call local
distributor.
PRESENCE OF
WATER IN PUMP OIL
Water sprayed at machine
Change oil. Direct spray away from machine.
High humidity in air
Check and change oil twice as often.
Piston packing worn. Oil seal worn. Call local distributor.