![background image](http://html1.mh-extra.com/html/landa/mhp4-30324e/mhp4-30324e_operators-manual_3654312022.webp)
22
Maintenance
PROBLEM
POSSIBLE CAUSE
SOLUTION
WATER
TEMPERATURE
TOO HOT
Incoming water to machine warm or hot
Lower incoming water temperature.
Fuel pump pressure too high
Call local Landa Dealer for proper fuel pressure.
Fuel pump defective
Replace fuel pump.
Detergent line sucking air
Tighten all clamps.
Check detergent lines for holes.
Defective high limit switch
Replace.
Incorrect fuel nozzle size
See breakdown for model.
Insufficient water supplied
Check water GPM to machine.
Restrict water flow
Check nozzle for obstruction and proper size.
DETERGENT NOT
DRAWING
Air leak
Tighten all clamps. Check detergent lines for
holes.
Valve in the injector head may be blocked,
dirty or damaged
Clean or replace valve in injector.
Filter screen on detergent suction hose
plugged.
Clean or replace.
Dried up detergent plugging metering valve Disassemble and clean thoroughly.
High viscosity of detergent
Dilute detergent to specifications.
Hole in detergent line(s)
Repair hole.
Low detergent level
Add detergent, if needed.
PUMP RUNNING
NORMALLY
BUT PRESSURE
LOW ON
INSTALLATION
Pump sucking air
Check water supply and possibility of air
seepage.
Valves sticking
Check and clean or replace if necessary.
Unloader valve seat faulty
Check and replace if necessary.
Nozzle incorrectly sized
Check and clean or replace if necessary.
(See serial plate for proper size.)
Worn piston packing
Check and replace if necessary.
FLUCTUATING
PRESSURE
Valves worn
Check and replace if necessary.
Blockage in valve
Check and replace if necessary.
Pump sucking air
Check water supply and
air seepage at joints in suction line.
Worn piston packing
Check and clean or replace if necessary.
Gasoline Engine Altitude
The gasoline engine is preset for operation at
altitudes below 1000 feet above sea level. If
operated at higher altitudes, it may be necessary
to install a high altitude main jet in the carburetor.
Contact your local authorized engine sales and
service center for details.
Landa MHP Operator’s Manual 8.913-925.0 - T