Landa MHP4-3000 User manual

MHP
For technical assistance or the dealer nearest you,
consult our web page at www.landa.com
8.913-925.0
OPERATOR’S MANUAL
L
I
S
T
E
D
®
89139250-7
 MHP4-3000  MHP4-3500

CONTENTS
2
Model Number ______________________________
Serial Number ______________________________
Date of Purchase ____________________________
The model and serial numbers will be found on a decal attached
to the pressure washer.You should record both serial number and
date of purchase and keep in a safe place for future reference.
LANDA MHP • 8.913-925.0 • Rev. 8/13
Introduction & Important Safety Information 4-5
Component Identification 6
Assembly Instructions 7
Operating Instructions 8
Detergents & General Washing Techniques 9
Shutdown & Cleanup 10
Troubleshooting 11-14
Preventative Maintenance 15-17
Maintenance Schedule & Oil Change Record 18
Exploded View, Control Panel and Parts List 19
Exploded View, Left Side, All Models 20
Exploded View, Right Side, All Models 21
Exploded View Parts List, All Models 22-23
Exploded View, Detergent/Float Combination 24
Detergent/Float Combination Parts List 25
Hose and Spray Gun Assembly 26
Downstream Injector Assembly 27
Pump Specifications 28-29
Landa Sure Fire Burner Replacement Parts 30-31
LT.1 Pump Exploded View and Parts List 32-33
VRT 3 Unloader Exploded View and Parts List 34
Warranty

LANDA MHP • 8.913-925.0 • Rev. 8/13
3
PRESSURE WASHER OPERATOR’S MANUAL
INTRODUCTION & IMPORTANT SAFETY INFORMATION
Thank you for purchasing this Pressure Washer.
We reserve the right to make changes at any time
without incurring any obligation.
Owner/User Responsibility:
The owner and/or user must have an understanding of
the manufacturer’s operating instructions and warnings
before using this pressure washer. Warning information
should be emphasized and understood. If the operator
is not fluent in English, the manufacturer’s instructions
and warnings shall be read to and discussed with
the operator in the operator’s native language by the
purchaser/owner, making sure that the operator com-
prehends its contents.
Owner and/or user must study and maintain for future
reference the manufacturers’ instructions.
The operator must know how to stop the machine
quickly and understand the operation of all controls.
Never permit anyone to operate the engine without
proper instructions.
SAVE THESE INSTRUCTIONS
This manual should be considered a permanent
part of the machine and should remain with it if
machine is resold.
When ordering parts, please specify model and
serial number. Use only identical replacement parts.
This machine is to be used only by trained operators.
IMPORTANT SAFETY
INFORMATION
READ OPERATOR’S
MANUAL THOROUGHLY
PRIOR TO USE.
WARNING: To reduce the risk of
injury, read operating instruc-
tions carefully before using.
1. Read the owner's manual
thoroughly. Failure to fol-
low instructions could cause
malfunction of the machine
and result in death, serious
bodily injury and/or property
damage.
2. Know how to stop the machine and bleed pressure
quickly. Be thoroughly familiar with the controls.
3. Stay alert — watch what you are doing.
WARNING
KEEP WATER
SPRAY AWAY FROM
ELECTRICAL WIRING.
WARNING: Keep wand, hose, and
water spray away from electric
wiring or fatal electric shock may
result.
4. All installations must comply
with local codes. Contact
your electrician, plumber,
utility company or the selling
distributor for specific details.
WARNING
EAR PROTECTION
MUST BE WORN
WARNING:This machine exceeds
85 db appropriate ear protection
must be worn.
WARNING
USE PROTECTIVE
EYE WEAR
AND CLOTHING
WHEN OPERATING
THIS EQUIPMENT.
WARNING: High pressure spray
can cause paint chips or other
particles to become airborne
and fly at high speeds. To avoid
personal injury, eye, hand and
foot safety devices must be
worn.
5. Eye, hand, and foot protection
must be worn when using this
equipment.
6. Keep operating area clear of all persons.
RISK OF EXPLOSION:
OPERATE ONLY WHERE
OPEN FLAME OR TORCH
IS PERMITTED
WARNING
WARNING: Flammable liquids
can create fumes which can ig-
nite, causing property damage
or severe injury.
WARNING: Risk of explosion —
Operate only where open flame
or torch is permitted.
RISK OF FIRE.
DO NOT ADD FUEL
WHEN OPERATING
MACHINE.
WARNING
WARNING: Risk of fire — Do not
add fuel when the product is
operating or still hot.
WARNING: Do not use gasoline
crankcase draining or oil con-
taining gasoline, solvents or
alcohol. Doing so will result in
fire and/or explosion.
WARNING: Risk of fire — Do not
Spray flammable liquids.
7. Allow engine to cool for 1-2 minutes before refu-
eling. If any fuel is spilled, make sure the area is
dry before testing the spark plug or starting the
engine. (Fire and/or explosion may occur if this is
not done.)
Gasoline engines on mobile or portable equipment
shall be refueled:
a. outdoors;
b. with the engine on the equipment stopped;
c. with no source of ignition within 10 feet of
the dispensing point; and
d. with an allowance made for expansion of the
fuel should the equipment be exposed to a
higher ambient temperature.

LANDA MHP • 8.913-925.0 • Rev. 8/13
OPERATOR’S MANUAL
PRESSURE WASHER
4
15. Be certain all quick coupler fittings are secured
before using pressure washer.
RISK OF INJECTION
OR SEVERE INJURY
TO PERSONS. KEEP
CLEAR OF NOZZLE.
WARNING
WARNING: High pressure devel-
oped by these machines will
cause personal injury or equip-
ment damage. Keep clear of
nozzle. Use caution when oper-
ating. Do not direct discharge
stream at people, or severe in-
jury or death will result.
WARNING
PROTECT FROM
FREEZING
WARNING: Protect machine from
freezing.
16. To keep machine in best
operating conditions, it is
important you protect machine
from freezing.Failure to protect
machine from freezing
could cause malfunction of the
machine and result in death,
serious bodily injury, and/or property damage. Fol-
low storage instructions specified in this manual.
17. Inlet water must be clean fresh water and no hotter
then 90°F.
WARNING
RISK OF
ASPHYXIATION. USE
THIS PRODUCT ONLY
IN A WELL
VENTILATED AREA.
WARNING: Risk of asphyxiation.
Use this product only in a well
ventilated area.
18. Avoid installing machines in
small areas or near exhaust
fans. Adequate oxygen is
needed for combustion or
dangerous carbon monoxide
will result.
19. Manufacturer will not be liable for any changes
made to our standard machines or any components
not purchased from us.
20. The best insurance against an accident is precau-
tion and knowledge of the machine.
WARNING
RISK OF INJURY
FROM FALLS WHEN
USING LADDER.
WARNING: Be extremely careful
when using a ladder, scaffolding
or any other relatively unstable
location. The cleaning area
should have adequate slopes
and drainage to reduce the pos-
sibility of a fall due to slippery
surfaces.
IMPORTANT SAFETY INFORMATION
In an overfilling situation, additional precautions are
necessary to ensure that the situation is handled
in a safe manner.
WARNING: Risk of injury. Disconnect battery
ground terminal before servicing.
8. When in use , do not place machine near flammable
objects as the engine is hot.
9. Oil burning appliances shall be installed only in
locations where combustible dusts and flammable
gases or vapors are not present. Do not store or
use gasoline near this machine.
10. Use No. 1 or No. 2 heating oil (ASTM D306) only.
NEVER use gasoline in your fuel oil tank. Gasoline
is more combustible than fuel oil and could result
in a serious explosion. NEVER use crankcase or
waste oil in your burner. Fuel unit malfunction could
result from contamination.
11. Do not confuse gasoline and fuel oil tanks. Keep
proper fuel in proper tank.
WARNING
RISK OF INJURY.
HOT SURFACES
CAN CAUSE BURNS
WARNING: Risk of injury. Hot
surfaces can cause burns. Use
only designated gripping areas
of spray gun and wand. Do not
place hands or feet on non-insu-
lated areas of the pressure
washer.
12. Transport/Repair with fuel tank EMPTY or with fuel
shut-off valve OFF.
HOT DISCHARGE FLUID:
DO NOT TOUCH OR
DIRECT DISCHARGE
STREAM AT PERSONS.
CAUTION: Hot discharge fluid.
Do not touch or direct discharge
stream at persons.
WARNING: This machine pro-
duces hot water and must have
insulated components attached
to protect the operator.
13. To reduce the risk of injury, close supervision is
necessary when a machine is used near children.
Do not allow children to operate the pressure
washer. This machine must be attended during
operation.
TRIGGER GUN KICKS
BACK - HOLD WITH
BOTH HANDS
WARNING
WARNING: Grip cleaning wand
securely with both hands before
starting. Failure to do this could
result in injury from a whipping
wand.
14. Never make adjustments on
machine while in operation.

LANDA MHP • 8.913-925.0 • Rev. 8/13
5
PRESSURE WASHER OPERATOR’S MANUAL
IMPORTANT SAFETY INFORMATION
21. Do not allow acids, caustic or abrasive fluids to pass
through the pump.
22. Never run pump dry or leave spray gun closed
longer than 1-2 minutes.
23. Machines with shut-off spray gun should not be
operated with the spray gun in the off position for
extensive periods of time as this may cause dam-
age to the pump.
24. Protect discharge hose from vehicle traffic and
sharp objects. Inspect condition of high pressure
hose before using or bodily injury may result.
25. Before disconnecting discharge hose from water
outlet, turn burner off and open spray gun to al-
low water to cool below 100° before stopping the
machine. Then open the spray gun to relieve pres-
sure. Failure to properly cool down or maintain the
heating coil may result in a steam explosion.
26. Do not overreach or stand on unstable support.
Keep good footing and balance at all times.
27. Do not operate this machine when fatigued or under
the influence of alcohol, prescription medications,
or drugs.
28. In oil burning models, use only kerosene, No. 1
home heating fuel, or diesel. If diesel is used, add
a soot remover to every tankful.
Follow the maintenance instructions speci-
fied in the manual.

LANDA MHP • 8.913-925.0 • Rev. 8/13
OPERATOR’S MANUAL
PRESSURE WASHER
6
COMPONENT IDENTIFICATION
89139250-4
Water
Supply Hose
(Not included)
Variable Pressure
Control Wand
Brass Soap
Nozzle
Pull Rope
High Pressure Hose
Swivel
Connector
Battery
Box
Quick Coupler
Collar
Detergent Injector
Discharge
Nipple
Detergent
Bucket
(Not Included)
Spray Gun
Detergent
Pick Up
Tube
Trigger
Control
Wand
Handle
Wand
Nozzle
Quick
Coupler
Fuel
Tank
Pump — Delivers a specific gpm to the high pressure
nozzle which develops pressure.
Spray Gun — Controls the application of water and
detergent onto cleaning surface with trigger device.
Includes safety latch.
Detergent Valve — Allows you to siphon and mix
detergents (Not Shown).
Wand — Must be connected to the spray gun.
High Pressure Hose — Connect one end to water
pump high pressure discharge nipple and the other
end to spray gun.
Rupture Disk — Secondary pressure release in the
unlikely event the unloader valve fails.
Unloader Valve — Safety device which, when the
spray gun closes, prevents over pressurization.
NOTE:If trigger on spray gun is released for more than
2 minutes, water will leak from the pump protector.
Warm water will discharge from pump protector onto
floor. This system prevents internal pump damage.
Rupture
Disk
Detergent
Valve
Temperature
Valve

LANDA MHP • 8.913-925.0 • Rev. 8/13
7
PRESSURE WASHER OPERATOR’S MANUAL
89139250-5
ASSEMBLY INSTRUCTIONS
STEP 1: Attach a 5/8" water supply
hose to inlet connector. Minimum
flow should be 5 GPM.
STEP 3: Attach variable pressure
control wand to spray gun and
swivel connector on high pressure
hose to spray gun using teflon tape
on threads to prevent leakage.
CAUTION: Engage the safety
latch on the spray gun trigger.
STEP 2: Attach high pressure hose
to discharge nipple using quick
coupler. Lock coupler securely into
place by pulling back coupler col-
lar and inserting it onto discharge
nipple and then pushing coupler
collar forward to lock in place.
STEP 5: Fill gasoline tank and
check engine oil level. Fill fuel oil
tank. Do not confuse gasoline and
fuel oil (diesel) tanks. Keep proper
fuel in proper tanks.
Trigger
Gun
High Pressure
Hose
Wand
Safety
Latch
STEP 4: Check oil level on sight
glass on side of pump. Oil should
be visible one-half way up sight
glass (SAE 30W non-detergent).
The oil level can also be checked
by using the dipstick on the top of
the pump.
Oil
Dipstick
STEP 6: Install proper battery mak-
ing sure that the red cable is at-
tached to the positive terminal. Use
a U1 30 amp garden tractor style
battery (battery not included).
Garden
Hose
Water
Inlet
Collar
High
Pressure
Hose
Discharge
Nipple
Red
Black

LANDA MHP • 8.913-925.0 • Rev. 8/13
OPERATOR’S MANUAL
PRESSURE WASHER
8
89139250-10
89139250-11
OPERATING INSTRUCTIONS
STEP 1: Read operator’s manual
before operating. Before installing
nozzle, turn on water supply and
run machine allowing water to flush
through the system until clear. Pull
wand coupler collar back, insert
desired pressure nozzle into cou-
pler, then secure by pushing collar
forward. CAUTION: Never replace
nozzles without engaging the safe-
ty latch on the spray gun trigger.
STEP 4: With spray nozzle pointed
away from you or anyone else, press
trigger on spray gun to obtain pres-
surized cold water spray.
STEP 2: Turn on water at faucet
and pull trigger on spray gun al-
lowing water to flow until all air has
discharged from system. Check
for water leaks; tighten as needed.
NOTE: Variable pressure control
wand handle must be turned clock-
wise to enable water to flow out of
the high pressure nozzle.
STEP 3: Read engine manual;
turn engine gas shutoff valve (if
equipped) and choke to run posi-
tion. Turn the engine switch to the
START position and hold it there
until the engine starts. NOTE: Do not
use the electric starter for more than
five seconds at a time. If the engine
fails to start, release the switch and
wait ten seconds before operating
the starter again. When the engine
starts, allow the engine switch to re-
turn to the ON position. If the engine
is to be started without the battery,
turn switch to start position and pull
rope to start. Turn off choke.
CAUTION: Small engines may
kick back. Do not hold pull rope
tightly in hand.
The four color-coded quick connect nozzles provide a
wide array of spray widths from 0° to 40° and are easily
accessible when placed in the convenient rubber nozzle
holder, which is provided on the front of the machine.
NOTE: For a more gentle rinse, select the white 40°
or green 25° nozzle. To scour the surface, select the
yellow 15° or red 0° nozzle.
Pressure
Nozzle
STEP 5: For hot water, turn the
burner switch ON when a steady
stream of water flows out of the
spray gun. Burner will light auto-
matically. For steam, open temper-
ature valve counterclockwise. This
lowers the pressure and raises the
temperature. NOTE: Do not start
machine with burner switch on.
Selection of high or low pressure is accompanied by
turning the handle. NOTE: High pressure nozzle must
be inserted at end of wand to obtain high pressure. To
apply soap, read washing techniques section.
Variable Pressure
Control Handle Trigger
Variable Pressure
Wand (VP)
High
Pressure
Nozzle
Brass Soap
Nozzle
Burner Switch Temperature
Valve
Engine
Switch
Choke

LANDA MHP • 8.913-925.0 • Rev. 8/13
9
PRESSURE WASHER OPERATOR’S MANUAL
WARNING: Some detergents
may be harmful if inhaled or
ingested, causing severe nau-
sea, fainting or poisoning. The
harmful elements may cause
property damage or severe
injury.
STEP 1: Use detergent designed
specifically for pressure washers.
Household detergents could dam-
age the pump. Prepare detergent
solution as required by the manu-
facturer. Fill a container with
pressure washer detergent. Place
the filter end of detergent suction
tube into the detergent container.
STEP 2: Connect detergent injector to discharge
nipple on machine. Connect high pressure hose to
injector with quick coupler (check to make sure locking
coupler sleeves are in proper position before applying
water pressure).
STEP 3: Open wand control
valve for low pressure allow-
ing detergent to siphon. Close
control valve for rinsing at
high pressure.
OPTION: Open detergent valve located on control
panel. The detergent valve controls detergent flow
by the number of turns of this valve. Close detergent
valve to rinse.
IMPORTANT: You must flush the detergent after
each use by placing the suction tube into a bucket
of clean water, follow step 3 or open detergent
valves then run the pressure washer for 1-2 min-
utes.
THERMAL PUMP
PROTECTION
If you run your pressure washer for 3-5 minutes without
pressing the trigger on the spray gun, circulating water
in the pump can reach high temperatures. When the
water reaches this temperature, the pump protector
engages and cools the pump by discharging the warm
water onto the ground. This thermal device prevents
internal damage to the pump.
CLEANING TIPS
Pre-rinse cleaning surface with fresh water. Place de-
tergent suction tube directly into cleaning solution and
apply to surface at low pressure (for best results, limit
your work area to sections approximately 6 feet square
and always apply detergent from bottom to top). Allow
detergent to remain on surface 1-3 minutes. Do not
allow detergent to dry on surface. If surface appears
to be drying, simply wet down surface with fresh water.
If needed, use brush to remove stubborn dirt. Rinse at
high pressure from top to bottom in an even sweep-
ing motion keeping the spray nozzle approximately
1 foot from cleaning surface. Use overlapping strokes
as you clean and rinse any surface. For best surface
cleaning action spray at a slight angle.
Recommendations:
 • Before cleaning any surface, an inconspicuous
area should be cleaned to test spray pattern and
distance for maximum cleaning results.
 • If painted surfaces are peeling or chipping,
use extreme caution as pressure washer may
remove the loose paint from the surface.
 • Keepthespraynozzleasafedistancefromthe
surface you plan to clean. High pressure wash
a small area, check the surface for damage
and if no damage is found, continue pressure
washing.
CAUTION - Never use:
 • Bleach,chlorineproductsandothercorrosive
chemicals
 • Liquidscontainingsolvents(i.e.,paintthinner,
gasoline, oils)
 • Tri-sodiumphosphateproducts
 • Ammoniaproducts
 • Acid-basedproducts
These chemicals will harm the machine and will
damage the surface being cleaned.
RINSING
It will take a few seconds for the detergent to clear.
Apply safety latch to spray gun and close detergent
valve. Select and install the desired high pressure
nozzle.
WARNING
DETERGENTS AND GENERAL WASHING TECHNIQUES
89139250-6
Detergent
Injector
Detergent
Valve
Discharge
Nipple
High
Pressure
Hose

LANDA MHP • 8.913-925.0 • Rev. 8/13
OPERATOR’S MANUAL
PRESSURE WASHER
10
89139250-8
SHUTTING DOWN AND CLEAN-UP
CAUTION: Always store your pressure washer in a
location where the temperature will not fall below
32°F (0°C).The pump in this machine is susceptible
to permanent damage if frozen. FREEZE DAMAGE
IS NOT COVERED BY WARRANTY.
1. Stop the pressure washer, squeeze spray gun
trigger to release pressure.
2. Detach water supply hose and high pressure
hose.
3. Turn on the machine for a few seconds, until re-
maining water exits. Turn engine off immediately.
4. Drain the gas and oil from the engine.
5. Do not allow high pressure hose to kink.
6. Store the machine and accessories in a room which
does not reach freezing temperatures.
CAUTION: Failure to follow the above directions will
result in damage to your pressure washer.
When the pressure washer is not being operated or is
being stored for more than one month, follow these
instructions:
1. Replenish engine oil to upper level.
2. Drain gasoline from fuel tank, fuel line, fuel valve
and carburetor.
3. Pour about one teaspoon of engine oil through
the spark plug hole, pull the starter grip several
times and replace the plug. Then pull the starter
grip slowly until you feel increased pressure which
indicates the piston is on its compression stroke and
leave it in that position. This closes both the intake
and exhaust valves to prevent rusting of cylinder.
4. Cover the pressure washer and store in a clean, dry
place that is well ventilated away from open flame
or sparks. NOTE: The use of a fuel additive, such
as STA-BIL®, or an equivalent, will minimize the
formulation of fuel deposits during storage. Such
additives may be added to the gasoline in the fuel
tank of the engine, or to the gasoline in a storage
container.
After Extended Storage
CAUTION: Prior to restarting, thaw out any
possible ice from pressure washer hoses,
spray gun or wand.
Engine Maintenance
During the winter months, rare atmospheric conditions
may develop which will cause an icing condition in the
carburetor. If this develops, the engine may run rough,
lose power and may stall. This temporary condition can
be overcome by deflecting some of the hot air from the
engine over the carburetor area. NOTE: Refer to the
engine manufacturer's manual for service and mainte-
nance of the engine.
STORAGE
STEP 2: Turn burner switch off
and continue spraying, allowing
the water to cool below 100°F.
STEP 4: Turn off water supply.
STEP 1: Remove detergent suction
tube from container and insert into
one gallon of fresh water. Open
detergent valve, pull trigger on
spray gun and siphon water for one
minute.
STEP 5: Open spray gun to relieve
remaining pressure.
STEP 3: Turn engine off.
Burner
Switch

LANDA MHP • 8.913-925.0 • Rev. 8/13
11
PRESSURE WASHER Troubleshooting Guide
TROUBLESHOOTING
PROBLEM POSSIBLE CAUSE SOLUTION
LOW
OPERATING
PRESSURE
Faulty pressure gauge Install new gauge.
Insufficient water supply Use larger garden hose; clean filter washer at
water inlet.
Old, worn or incorrect spray
nozzle
Match nozzle number to machine and/or
replace with new nozzle.
Plumbing or hose leak Check plumbing system for leaks. Retape
leaks with teflon tape.
Faulty or misadjusted unloader
valve (Where applicable)
Adjust unloader for proper pressure. Install
repair kit when needed.
Worn packing in pump Install new packing kit.
Fouled or dirty inlet or discharge
valves in pump
Clean inlet and discharge valves.
Worn inlet or discharge valves Replace with valve kit.
Leaking pressure control valve
(Where applicable)
Rebuild or replace as needed.
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.
Slow engine RPM Set engine speed at proper specifications.
(3400 - 3600 RPM.)
BURNER
WILL NOT
LIGHT
(Continued on
next page)
Little or no fuel Fill tank with fuel.
Improper fuel or water in fuel Check and replace if necessary.
Clogged fuel line Clean or replace.
Plugged fuel filter Replace as needed.
Misadjusted burner air bands Replace air bands for clean burn.
Little or no fuel pressure from fuel
pump
Increase fuel pressure to specification and/or
replace fuel pump.
Faulty burner transformer Test transformer for proper arc between
contacts. Replace as needed.
Disconnected or short in electrical
wiring
All wire contacts should be clean and tight.
No breaks in wires.
Flex coupling slipping on fuel
pump shaft or burner motor shaft
Replace if needed.
On-Off switch defective Check for electrical current reaching
burner assembly with burner switch on.
Heavy sooting on coil and burner
can cause interruption of air flow
and shorting of electrodes
Clean as required.
Improper electrode setting Check and reset according to diagram in
Operator’s Manual
Fuel not reaching combustion
chamber
Check fuel pump for proper flow. Check
solenoid flow switch on machines with spray
gun control, for proper on-off fuel flow control.

LANDA MHP • 8.913-925.0 • Rev. 8/13
PRESSURE WASHER Troubleshooting Guide
12
TROUBLESHOOTING
PROBLEM POSSIBLE CAUSE SOLUTION
BURNER
WILL NOT
LIGHT
(continued from
previous page)
Clogged burner nozzle Clean as required.
Thermostat faulty or slow engine speed Increase engine RPM to increase voltage.
Flow switch malfunction Remove, test for continuity and replace as
needed.
Flow solenoid malfunction Replace if needed.
25 Amp circuit breaker tripped Push reset button.
Bridge rectifier defective Test and replace.
12V DC relay defective Test and replace.
Fuel is not reaching combustion
chamber
Check fuel pump for proper flow. Check
solenoid flow switch on machines with spray
gun control for proper on-off flow control.
MACHINE
SMOKES
Improper fuel or water in fuel Drain tank and replace contaminated fuel.
Improper air adjustment Readjust air bands on burner assembly.
Low fuel pressure Adjust fuel pump pressure to specifications.
Plugged or dirty burner nozzle Replace nozzle.
Faulty burner nozzle spray pattern Replace nozzle.
Heavy accumulation of soot on coils
and burner assembly
Remove coils and burner assembly, clean
thoroughly.
Misaligned electrode setting Realign electrodes to specifications.
Obstruction in smoke stack Check for insulation blockage or other foreign
objects.
Low engine RPM Increase RPM.
LOW
WATER
TEMPERATURE
Improper fuel or water in fuel Replace with clean and proper fuel.
Low fuel pressure Increase fuel pressure.
Weak fuel pump Check fuel pump pressure. Replace pump if
needed.
Fuel filter partially clogged Replace as needed.
Soot build-up on coils not allowing heat
transfer
Clean coils.
Improper burner nozzle See specifications.

LANDA MHP • 8.913-925.0 • Rev. 8/13
13
PRESSURE WASHER Troubleshooting Guide
TROUBLESHOOTING
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 pres-
sure.
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 • 8.913-925.0 • Rev. 8/13
PRESSURE WASHER Troubleshooting Guide
14
TROUBLESHOOTING
PROBLEM POSSIBLE CAUSE SOLUTION
PUMP
NOISY
Air in suction line Check water supply and connections on
suction line.
Broken or weak inlet or discharge valve
springs
Check and replace if necessary.
Excessive matter in valves. Check and clean if necessary.
Worn bearings Check and replace if necessary.
PRESENCE
OF WATER
IN OIL
Oil seal worn Check and replace if necessary.
High humidity in air Check and change oil twice as often.
WATER
DRIPPING
FROM UNDER
PUMP
Piston packing worn Check and replace if necessary.
O-Ring plunger retainer worn. Check and replace if necessary.
Cracked piston Check and replace if necessary.
Pump protector Lower water supply pressure. Do not run
with spray gun closed longer than 5 minutes.
OIL
DRIPPING
Oil seal worn Check and replace if necessary.
EXCESSIVE
VIBRATION IN
DELIVERY LINE
Irregular functioning of valves Check and replace if necessary.
BURNER
MOTOR WILL
NOT RUN
Fuel pump seized Replace fuel pump.
Burner fan loose or misaligned Position correctly, tighten set screw.
Defective control switch Replace switch.
Loose wire Check and replace or tighten wiring.
Defective burner motor Replace motor
RELIEF VALVE
LEAKS WATER
Relief valve defective Replace or repair.

LANDA MHP • 8.913-925.0 • Rev. 8/13
15
PRESSURE WASHER OPERATOR’S MANUAL
1. Check to see that water pump is properly
lubricated.
2. Follow winterizing instructions to prevent freeze
damage to pump and coils.
3. Always neutralize and flush detergent from system
after use.
4. If water is known to be high in mineral content, use
a water softener on your water system, or de-scale
as needed.
5. Do not allow acidic, caustic or abrasive fluids to
be pumped through system.
6. Always use high grade quality Landa cleaning
products.
7. Never run pump dry for extended periods of
time.
8. Use clean fuel — kerosene, No. 1 fuel oil, or diesel.
Replace fuel filter every 100 hours of operation.
Avoid water contaminated fuel as it will seize up
the fuel pump.
9. If machine is operated with smoky or eye burning
exhaust, coils will soot up, not letting water reach
maximum operating temperature. (See section on
Air Adjustments).
10. Never allow water to be sprayed on or near the
engine, the burner assembly or any electrical
components.
11. Periodically delime coils per instructions.
12. Check to see that engine is properly lubricated.
It is advisable, periodically, to visually inspect the
burner. Check air inlet to make sure it is not clogged
or blocked. Wipe off any oil spills and keep this equip-
ment clean and dry.
The areas around the Landa washer should be kept
clean and free of combustible materials, gasoline and
other flammable vapors and liquids.
The flow of combustion and ventilating air to the burner
must not be blocked or obstructed in any manner.
MAINTENANCE AND SERVICE
Unloader Valves
Unloader valves relieve pressure in the line when a
spray gun is closed. Unloader valves are preset and
tested at the factory before shipping. Tampering with
the factory setting may cause personal injury and/or
property damage, and will void the manufacturer's
warranty.
Winterizing Procedure
Damage due to freezing is not covered by warranty.
Adhere to the following cold weather procedures when-
ever the washer must be stored or operated outdoors
under freezing conditions.
PREVENTATIVE MAINTENANCE
During winter months, when temperatures drop below
32°F, protecting your machine against freezing is
necessary. Store the machine in a heated room. If this
is not possible then mix a 50/50 solution of antifreeze
and water into a 5 gallon bucket. Place a short section
of garden hose into the bucket and connect it to the
machine. Elevate the bucket and turn the pump on
to siphon the antifreeze through the machine. If com-
pressed air is available an air fitting can be screwed
into the inlet connector and, by injecting compressed
air, all water will be blown out of the system.
High Limit Hot Water Thermostat
For safety, each machine is equipped with a high
limit control switch. In the event the temperature of
the water should exceed its operating temperature
the high limit control will turn the burner off until the
water cools.
Pumps
Use only SAE 30 weight non-detergent oil. Change
oil after first 50 hours of use. Thereafter, change oil
every three months or at 500 hour intervals. Oil level
should be checked through use of dipstick found on
top of pump.
Cleaning Of Coils
In alkaline water areas, lime deposits can accumulate
rapidly inside the coil pipes. This growth is increased
by the extreme heat build up in the coil. The best
preventative for liming conditions is to use high quality
cleaning detergents. In areas where alkaline water is
an extreme problem, periodic use of Landa Deliming
Powder (Landa Part #9-028008) will remove lime
and other deposits before coil becomes plugged.
(See Deliming Instructions for use of Landa Deliming
Powder.)
Deliming Coils
Periodic flushing of coils or optional float tank is rec-
ommended.
Step 1 Fill a container with 4 gallons of water,
then add 1 lb. of deliming powder. Mix thor-
oughly.
Step 2 Remove wand assembly from spray gun and
put spray gun into container or optional float
tank. Secure the trigger on the spray gun
into the open position.
Step 3 Attach a short section (3-5 ft.) of garden
hose to machine to siphon solution from
an elevated container. Turn engine on, al-
lowing solution to be pumped through coils
back into the container. Solution should be
allowed to circulate 2-4 hours.

LANDA MHP • 8.913-925.0 • Rev. 8/13
OPERATOR’S MANUAL
PRESSURE WASHER
16
Step 4 After circulating solution flush entire system
with fresh water. Reinstall wand assembly to
spray gun.
Removal of Soot and Heating Coil
In the heating process, fuel residue in the form of soot
deposits may develop between the heating coil pipe
and block air flow which will affect burner combustion.
When soot has been detected on visual observation,
the soot on the coil must be washed off after following
the coil removal steps (See Coil Removal on page
17).
Rupture Disk
If pressure from pump or thermal expansion should
exceed safe limits, the rupture disk will burst, allow-
ing high pressure to be discharged through hose
to ground. When the disk ruptures it will need to be
replaced.
Fuel
Use clean fuel oil that is not contaminated with water
and debris. Replace fuel filter and drain tank every
100 hours of operation. Use No. 1 or No. 2 Heating
oil (ASTM D306) only. NEVER use gasoline in your
burner tank. Gasoline is more combustible than fuel
oil and could result in a serious explosion. NEVER
use crankcase or waste oil in your burner. Fuel unit
malfunction could result from contamination.
Fuel Control System
These machines utilize a fuel solenoid valve located
on the fuel pump to control the flow of fuel to the
combustion chamber. This solenoid valve, which is
normally closed, is activated by a flow switch when
water is flowing through it.When an operator releases
the trigger on the spray gun, the flow of water through
the flow switch stops, turning off the current to the fuel
solenoid. The solenoid then closes, shutting off the
supply of fuel to the combustion chamber. Controlling
the flow of fuel in this way allows for an instantaneous
burn or no burn situation, thereby eliminating high
and low water temperatures, and combustion smoke
normally associated with machines incorporating a
spray gun.
CAUTION: Periodic inspection is recommended
to insure that the fuel solenoid valve functions
properly. This can be done by operating the ma-
chine and checking to see that when the trigger
on the spray gun is in the off position, the burner
is not firing.
Fuel Pressure Adjustment
To adjust fuel pressure, turn the adjusting screw
clockwise to increase, counterclockwise to decrease.
Do not exceed 200 PSI.
NOTE: When changing fuel pump, a bypass plug must
be installed in return port or fuel pump will not prime.
Electrode Setting
Burner Nozzle
Keep the tip free of surface deposits by wiping it with
a clean, solvent-saturated cloth, being careful not to
plug or enlarge the nozzle. For maximum efficiency,
replace the nozzle each season.
Beckett Burner Air Adjustment
The oil burner on this machine is preset for operation
at altitudes below 1000 feet. If operated at higher
altitudes, it may be necessary to adjust the air band
setting. Adjust air band for a #1 or #2 smoke spot on
the Bacharach scale. A one-time initial correction for
your location will pay off in economy, performance,
and extended service life. If a smoky or eye-burning
exhaust is being emitted from the stack, two things
should be checked. First, check the fuel to be certain
that kerosene or No. 1 home heating fuel is being
used. Next, check the air adjustment on the burner.
PREVENTATIVE MAINTENANCE
5/32"
1/4"
Electrode
Nozzle
5/32"
Air Band
Fuel Pump
Air
Adjustment
Screw

LANDA MHP • 8.913-925.0 • Rev. 8/13
17
PRESSURE WASHER OPERATOR’S MANUAL
Initial Air Adjustments: Allow sufficient air to obtain
a clean burning flame by loosening the lock screws
and moving the air shutter and if necessary the bulk
air band.
Reduce the air supply until the flame tips appear
slightly smoky, then increase the air just enough to
cause the flame tips to appear absolutely clean.
Landa Sure Fire Oil Burner
Burner Air Adjustment: The oil burner on this
machine is preset for operation at altitudes below 1000
feet. If operated at higher altitudes, it may be neces-
sary to adjust the air band for a #1 or #2 smoke spot
on the Bacharach scale.
To adjust, start machine and turn burner ON. Loosen
two locking screws found on the air band and close air
band until black smoke appears from burner exhaust
vent. Note air band position. Next, slowly open the air
band until white smoke just starts to appear. Turn air
band halfway back to the previously noted position.
Tighten locking screws.
Burner Air Adjustment
Reference
Numbers
Air Band Locking Screws
Air Band
CAUTION: If white smoke appears from burner
exhaust vent during start-up or operation,
discontinue use and readjust air bands.
NOTE: If a flue is installed, have a professional
serviceman adjust your burner for a #1 or #2 smoke
spot on the Bacharach scale.
PREVENTATIVE MAINTENANCE
Coil Removal
Removal of coil because of freeze breakage, or to clean
soot from it can be done quickly and easily.
Step 1 Disconnect hose from pump to inlet side
of the coil.
Step 2 Disconnect electrical connection
to the thermostat.
Step 3 Remove quick coupler from discharge
side of coil.
Step 4 Remove burner assembly from
combustion chamber.
Step 5 Remove the 3-3/8" bolts from each side
of coil and tank assembly (these bolts
are used to fasten tank to chassis).
Step 6 Disconnect 1/2" pipe nipples from inlet
and discharge side of coil.
Step 7 Remove top tank wrap exposing
insulation and coil and fold back
insulation.
Step 8 Remove bolts that hold down coil to
bottom wrap.
Step 9 Remove coil.
Replace or repair any insulation found to be torn
or broken.
Coil Reinstallation
Reinstall new or cleaned coil by reversing
the steps above.
Final Note —
The DC motors used on 12V DC burners can draw as
much as 20 amps! For the burner to run properly, the
battery and engine charging system must be kept in
good condition, and the engine must run fast enough
to adequately charge the battery. Do not throttle down
the engines for any length of time.

LANDA MHP • 8.913-925.0 • Rev. 8/13
OPERATOR’S MANUAL
PRESSURE WASHER
18
This pressure washer was produced with the best available materials and quality craftsmanship. However, you
as the owner have certain responsibilities for the correct care of the equipment. Attention to regular preventa-
tive maintenance procedures will assist in preserving the performance of your equipment. Contact your Landa
dealer for maintenance. Regular preventative maintenance will add many hours to the life of your pressure
washer. Perform maintenance more often under severe conditions.
OIL CHANGE RECORD
PREVENTATIVE MAINTENANCE
MAINTENANCE SCHEDULE
Engine Oil
Inspect Daily
Change Every 25 hours
Filter Every 50 hours
Air Cleaner
Inspect Every 50 hours or monthly
Clean Every 3 months
Battery Level Check monthly
Engine Fuel Filter 500 hours or 6 months
Spark Plug Maintenance 500 hours or 6 months
Clean Fuel Tank(s) Annually
Replace Fuel Lines Annually
Pump Oil
(Non-detergent
10/40W)
Inspect Oil level daily
Change After first 50 hours, then every 500 hours or annually
Clean Burner Filter Monthly (More often if fuel quality is poor)
Remove Burner Soot Annually
Burner Adjustment/Cleaning Annually
Replace Burner Nozzle Annually
Descale Coil Annually (More often if required)
Replace High Pressure Nozzle Every 6 months
Replace Quick Connects Annually
Clean Water Screen/Filter Weekly
Replace HP Hose Annually
Date Oil Changed
Month/Day/Year
Estimated Operating
Hours Since Last
Oil Change
Date Oil Changed
Month/Day/Year
Estimated Operating
Hours Since Last
Oil Change

LANDA MHP • 8.913-925.0 • Rev. 8/13
19
PRESSURE WASHER OPERATOR’S MANUAL
89139250-9
ITEM PART NO. DESCRIPTION QTY
1 9.802-771.0 Screw, 10/32" x 3/4" BH SOC 3
2 8.912-711.0 Box, MHP Electrical, Welded 1
3 9.802-530.0 Rectifier, Bridge, MB156,
12 VDC, 30 Amp 1
4 9.802-470.0 Relay, P & B/VF41F11, 12 VDC,
40 Amp (11,13 HP Honda) 1
9.802-471.0 Relay, 24 V DC, 40 Amp
(16 HP Vanguard) 1
5 8.912-705.0 Panel, MHP Control 1
6 8.750-246.0 Screw, 1/4" x 1/2" Whiz Loc 5
7 9.802-064.0 Grommet, 1/8" Rubber 4
8 9.802-759.0 Screw,
10/32" x 1/2" BHSOC
Blk
6
9 9.802-485.0 Breaker, Circuit, 25 Amp 1
10 9.802-794.0 Nut, Cage, 1/4" x 12 Gauge 13
11 8.912-712.0 Cover, MHP Control 1
12 9.802-283.0 Meter, Hour 1
ITEM PART NO. DESCRIPTION QTY
13 9.802-453.0 Switch, Curvette 120 V
& 220 V 1
14 9.802-456.0 Light, Indicator, Green
12 VDC 1
15 8.902-427.0  Valve Assy, Chemical,
Skid 1
16 8.900-300.0 Label, Landa Logo 1
17 8.900-297.0 Label, Nozzle/Det Valve,
MHP 1
18 8.932-968.0 Label, “Outdoor Use” 1
19 9.802-695.0 Nut, 10/32" 4
20 9.800-034.0 Lexan, Cover, Outdoor 1
21 8.900-296.0 Label, Control Box 1
22 9.802-791.0 Nut, Cage, 10/32" 16 Gauge 8
23 9.800-094.0 Label, Instruction/Warning 1
24 9.800-049.0 Label,
Manuf. Cleaning Solution 1
 Not Shown
10
2
3
4
5
6
7
8
911
12
13 14
15
16
17
21
8
22
8
22
18
24
1
19
23
19
(Reversed View)
19
8
6

EXPLODED VIEW - CONTROL PANEL
CONTROL PANEL PARTS LIST
23
24
20

LANDA MHP • 8.913-925.0 • Rev. 8/13
OPERATOR’S MANUAL
PRESSURE WASHER
20
EXPLODED VIEW - LEFT SIDE
EXPOSEDPULLEYS AND
BELTSCAN CAUSE INJURY
PRECAUCION/AVERTISSEMENT
WARNING
EXPOSEDPULLEYS AND
BELTSCAN CAUSE INJURY
PRECAUCION/AVERTISSEMENT
WARNING
89139250-2
1
65
2
3
13
7
6
4
5
32
85
19
20
21
18
15
16
17
28
76
33
73 70
74
72
24
35
26
25
23
22
62
60
59
64
9
10
8
12
11
115
91
116 117
118
71
77
90
94
90
91
17
35
92
15 111
113
113
21
114
112
65