Troubleshooting - Kärcher HD 3.0/27 G Service Manual

For Models: HD3.0/27 GB, HD 3.3/35 GB, HD 4.0/40 GB
PROBLEM
LOW OPERATING
PRESSURE
FLUCTUATING
PRESSURE
PRESSURE LOW
AFTER PERIOD OF
NORMAL USE
ENGINE WILL NOT
START OR STOPS
WHILE OPERATING
ENGINE IS
OVERLOADED

TROUBLESHOOTING

POSSIBLE CAUSE
Faulty pressure gauge
Insuffi cient water supply
Old, worn or incorrect spray nozzle
Belt slippage
Plumbing or hose leak
Faulty or mis-adjusted unloader
valve
Worn packing in pump
Fouled or dirty inlet or discharge
valves in pump
Worn inlet or discharge valves
Obstruction in spray nozzle
Leaking pressure control valve
Slow engine RPM
Pump sucking air
Valves sticking
Unloader valve seat faulty
Worn or dirty pump valves
Nozzle is obstructed
Pump sucking air, inlet hose
leaking
Insuffi cient water supply
Nozzle worn
Unloader valve worn
Low oil shutdown
Out of gas
Water in gasoline
Nozzle partially blocked
Excessive pressure from high
engine RPM
9.801-760.0 • Rev. 03/16
HD 4.0/40 GeB
,
SOLUTION
Install new gauge.
Use larger supply hose; clean fi lter at water
inlet.
Match nozzle number to machine and/or
replace with new nozzle.
Tighten or replace; use correct belt.
Check plumbing system for leaks. Re-tape
leaks with tefl on tape.
Adjust unloader for proper pressure. Install
repair kit when needed.
Install new packing kit.
Clean inlet and discharge valves.
Replace with valve kit.
Remove obstruction.
Rebuild or replace as needed.
Set engine speed at proper specifi cations.
Check water supply and possibility of air
seepage.
Check and clean or replace if necessary.
Check and replace if necessary.
Call local distributor.
Blow out or remove debris with fi ne needle.
Check that all hoses and fi ttings are airtight.
Turn off machine and trigger spray gun until
a steady fl ow of water emerges through the
nozzle.
Turn water on full force. Check garden hose
for kinks, leaks or blockage.
Replace nozzle.
Replace unloader valve.
Fill engine with oil.
Fill fuel tank.
Drain gas tank; fi ll with clean fuel.
Clean nozzle.
Adjust engine throttle to lower RPM.
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