Simpson ALH3425 User manual

Part No. 7107205 Rev. 2 FEB2016
3400 PSI
2.5 GPM
PREMIUM PRESSURE WASHER
INSTRUCTION MANUAL
MANUEL D’UTILISATION
MANUAL DE
INSTRUCCIONES
MODEL
MODÈLE
MODELO
ALH3425
If your pressure washer is not working properly or if there are parts missing or broken,
please DO NOT RETURN IT TO THE PLACE OF PURCHASE. Contact our Customer
Service Department at 1-877-362-4271 or www.simpsoncleaning.com
Si votre rondelle de pression ne travaille pas convenablement ou s'il y a des
parties manquant ou cassé, s'il vous plaît le PAS LE RETOURNE AU LIEU
D'ACHAT. Contacter notre département de service clients à 1-877-362-4271 o
www.simpsoncleaning.com
Si su lavadora a presión no trabaja correctamente ó encuentra partes rotas
ófaltantes, por favor NO LA REGRECE AL LUGAR DONDE LA COMPRO.
Contáctese con nuestro Departamento de Servicio al Cliente llamando al
1-877-362-4271 ou www.simpsoncleaning.com
IMPORTANT: Please make certain that the person who is to use this equipment carefully
reads and understands these instructions before operating.
IMPORTANT : Assurez-vous que toute personne qui utilisera cet équipement lise
attentivement ces instructions avant de l’utiliser.
IMPORTANTE: Aségurese por favor de que la persona que vaya a utilizar este equipo lea
con cuidado y comprenda estas instrucciones antes de operar.
VEA EL ESPAÑOL EN LA CONTRAPORTADA. INSTRUCTIVO DE OPERACIÓN,
CENTROS DE SERVICIO Y PÓLIZA DE GARANTÍA. ADVERTENCIA:
LÉASE ESTE INSTRUCTIVO ANTES DE USAR EL PRODUCTO.
SAVE THIS MANUAL FOR FUTURE REFERENCE
LISEZ ET CONSERVEZ CES INSTRUCTIONS
CONSERVE ESTAS INSTRUCCIONES PARA FUTURAS CONSULTAS

2- ENG
SAFETY GUIDELINES - DEFINITIONS
This manual contains information that is important for you to know and understand.
This information relates to protecting YOUR SAFETY and PREVENTING
EQUIPMENT PROBLEMS. To help you recognize this information, we use the
symbols below. Please read the manual and pay attention to these symbols.
DANGER: Indicates an imminently hazardous situation which, if not avoided,
will result in death or serious injury.
WARNING: Indicates a potentially hazardous situation which, if not avoided,
could result in death or serious injury.
CAUTION: Indicates a potentially hazardous situation which, if not avoided, may
result in minor or moderate injury.
NOTICE: Indicates a practice not related to personal injury which, if not avoided,
may result in property damage.
IMPORTANT SAFETY INSTRUCTIONS
DANGER: Carbon Monoxide. Using an engine indoors can kill you in
minutes. Engine exhaust contains high levels of carbon monoxide (CO), a
poisonous gas you cannot see or smell. You may be breathing CO even if you
do not smell engine exhaust.
• NEVER use an engine inside homes, garages, crawlspaces or other partly
enclosed areas. Deadly levels of carbon monoxide can build up in these areas.
Using a fan or opening windows and doors does NOT supply enough fresh air.
• ONLY use outdoors and far away from open windows, doors and vents. These
openings can pull in engine exhaust.
• Even when the engine is used correctly, CO may leak into your home. ALWAYS use
a battery-powered or battery backup CO alarm in your house. Read and follow all
directions for CO alarm before using. If you feel sick, dizzy or weak at anytime,
move to fresh air immediately. See a doctor. You could have carbon monoxide
poisoning.
WARNING: Do not operate this unit until you read this instruction manual and
the engine instruction manual for safety, operation and maintenance instructions. If
you have any questions regarding the product, please contact our customer
service department at www.simpsoncleaning.com.
DANGER: Risk of injection or severe injury. Keep clear of nozzle. Do not
direct discharge stream at persons or live animals. This product is to be used
only by trained operators.
WARNING: This product and its exhaust contain chemicals known to the State
of California to cause cancer, birth defects or other reproductive harm. In addition,
some cleaning products and dust contain chemicals known to the State of
California to cause cancer, birth defects or other reproductive harm. Wash hands
after handling.

3- ENG
WARNING: This product may not be equipped with a spark-arresting muffler.
If the product is not equipped and will be used around flammable materials or
on land covered with materials such as agricultural crops, forest, brush, grass or
other similar items, then an approved spark arrester must be installed and is legally
required in the state of California. It is a violation of California statutes section
130050 and/or sections 4442 and 4443 of the California Public Resources Code,
unless the engine is equipped with a spark arrester, as defined in section 4442, and
maintained in effective working order. Spark arresters are also required on some
U.S. Forest Service land and may also be legally required under other statutes and
ordinances.
SAVE THESE INSTRUCTIONS
DANGER: RISK OF EXPLOSION OR FIRE
WHAT CAN HAPPEN HOW TO PREVENT IT
• Spilled gasoline and it’s vapors can
become ignited from cigarette sparks,
electrical arcing, exhaust gases and
hot engine components such as the
muffler.
• Shut off engine and allow it to cool before
adding fuel to the tank.
• Use care in filling tank to avoid spilling fuel.
Move pressure washer away from fueling
area before starting engine.
• Heat will expand fuel in the tank which
could result in spillage and possible
fire explosion.
• Keep maximum fuel level 1/2" (12.7mm)
below bottom of filler neck to allow for
expansion.
• Operating the pressure washer in an
explosive environment could result in
a fire.
• Operate and fuel equipment in well-
ventilated areas free from obstructions.
Equip areas with fire extinguisher suitable
for gasoline fires.
• Materials placed against or near the
pressure washer can interfere with
its proper ventilation features causing
overheating and possible ignition of
the materials.
• Never operate pressure washer in an area
containing dry brush or weeds.
• Muffler exhaust heat can damage
painted surfaces, melt any material
sensitive to heat (such as siding,
plastic, rubber, vinyl or the pressure
hose, itself), and damage live plants.
• Always keep pressure washer a minimum
of 4' (1.2m) away from surfaces (such as
houses, automobiles or live plants) that
could be damaged from muffler exhaust
heat.
• Improperly stored fuel could lead to
accidental ignition. Fuel improperly
secured could get into the hands of
children or other unqualified persons.
• Store fuel in an OSHA approved contain-
er, in a secure location away from work
area.
• Use of acids, toxic or corrosive
chemicals, poisons, insecticides, or
any kind of flammable solvent with
this product could result in serious
injury or death.
• Do not spray flammable liquids.

4- ENG
DANGER: RISK TO BREATHING (ASPHYXIATION)
WHAT CAN HAPPEN HOW TO PREVENT IT
• Breathing exhaust fumes will cause
serious injury or death! Engine
exhaust contains carbon monoxide,
an odorless and deadly gas.
• Operate pressure washer in a well-
ventilated area. Avoid enclosed areas
such as garages, basements, etc.
• Never operate unit in or near a location
occupied by humans or animals.
• Some cleaning fluids contain
substances which could cause injury
to skin, eyes or lungs.
• Use only cleaning fluids specifically rec-
ommended for high pressure washers.
Follow manufacturers recommendations.
Do not use chlorine bleach or any other
corrosive compound.
DANGER: RISK OF FLUID INJECTION AND LACERATION
WHAT CAN HAPPEN HOW TO PREVENT IT
• Your pressure washer operates at fluid
pressures and velocities high enough
to penetrate human and animal flesh
which could result in amputation or
other serious injury. Leaks caused
by loose fittings or worn or damaged
hoses can result in injection injuries.
DO NOT TREAT FLUID INJECTION
AS A SIMPLE CUT! See a physician
immediately!
• Inspect the high pressure hose regularly.
Replace the hose immediately if it is
damaged, worn, has melted from
contacting the engine, or shows any signs
of cracks, bubbles, pinholes, or other
leakage. Never grasp a high pressure
hose that is leaking or damaged.
• Never touch, grasp or attempt to cover a
pinhole or similar water leak on the high
pressure hose. The stream of water IS
under high pressure and WILL penetrate
skin.
• Never place hands in front of nozzle.
• Direct spray away from self and others.
• Make sure hose and fittings are tightened
and in good condition. Never hold onto
the hose or fittings during operation.
• Do not allow hose to contact muffler.
• Never attach or remove wand or hose
fittings while system is pressurized.
• When using replacement lances or guns
with this pressure washer, DO NOT use
a lance and/or lance/gun combination
that is shorter in length than what was
provided with this pressure washer as
measured from the nozzle end of the
lance to the gun trigger.
• Injuries can result if system pressure
is not reduced before attempting
maintenance or disassembly.
• To relieve system pressure, shut off
engine, turn off water supply and pull gun
trigger until water stops flowing.
• Use only accessories rated equal to or
higher than the rating of the pressure
washer.

5- ENG
DANGER: RISK OF INJURY FROM SPRAY
WHAT CAN HAPPEN HOW TO PREVENT IT
• High-velocity fluid spray can cause
objects to break, projecting particles
at high speed.
• Always wear ANSI-approved Z87.1
safety glasses. Wear protective clothing
to protect against accidental spraying.
• Never point wand at or spray people or
animals.
• Light or unsecured objects can
become hazardous projectiles. • Always secure trigger lock when wand is not in service to prevent accidental
operation.
• Never permanently secure trigger in pull-
back (open) position.
DANGER: RISK OF UNSAFE OPERATION
WHAT CAN HAPPEN HOW TO PREVENT IT
• Unsafe operation of your pressure
washer could lead to serious injury or
death to you or others.
• Do not use chlorine bleach or any other
corrosive compound.
• Become familiar with the operation and
controls of the pressure washer.
• Keep operating area clear of all persons,
pets and obstacles.
• Do not operate the product when fatigued
or under the influence of alcohol or drugs.
Stay alert at all times.
• Never compromise the safety features of
this product.
• Do not operate machine with missing,
broken or unauthorized parts.
• Never leave wand unattended while unit is
running.
• If proper starting procedure is not
followed, engine can kickback causing
serious hand and arm injury.
• If engine does not start after two pulls,
squeeze trigger of gun to relieve pump
pressure. Pull starter cord slowly until
resistance is felt. Then pull cord rapidly to
avoid kickback and prevent hand or arm
injury.
• The spray gun/wand is a powerful
cleaning tool that could look like a toy
to a child.
• Keep children away from the pressure
washer at all times.
• Reactive force of spray will cause gun/
wand to kickback, and could cause
the operator to slip or fall or misdirect
the spray. Improper control of gun/
wand can result in injuries to self and
others.
• Do not overreach or stand on an unstable
support.
• Do not use pressure washer while
standing on a ladder.
• Grip gun/wand firmly with both hands.
Expect the gun to kickback when
triggered.

6- ENG
DANGER: RISK OF INJURY OR PROPERTY DAMAGE WHEN
TRANSPORTING OR STORING
WHAT CAN HAPPEN HOW TO PREVENT IT
• Fuel or oil can leak or spill and could
result in fire or breathing hazard.
Serious injury or death can result.
Fuel or oil leaks will damage carpet,
paint or other surfaces in vehicles or
trailers.
• Oil could fill the cylinder and damage
the engine if the unit is not stored or
transported in an upright position.
• If pressure washer is equipped with a fuel
shut-off valve, turn the valve to the OFF
position before transporting to avoid fuel
leaks. If pressure washer is not equipped
with a fuel shut-off valve, drain the fuel
from tank before transporting. Only trans-
port fuel in an OSHA-approved container.
Always place pressure washer on a
protective mat when transporting to
protect against damage to vehicle from
leaks.
Always transport and store unit in an
upright position. Remove pressure
washer from vehicle immediately upon
arrival at your destination.
DANGER: RISK OF ELECTRICAL SHOCK
WHAT CAN HAPPEN HOW TO PREVENT IT
• Spray directed at electrical outlets or
switches, or objects connected to an
electrical circuit, could result in a fatal
electrical shock.
• Unplug any electrically operated product
before attempting to clean it. Direct spray
away from electric outlets and switches.
DANGER: RISK OF CHEMICAL BURN
WHAT CAN HAPPEN HOW TO PREVENT IT
• Use of acids, toxic or corrosive
chemicals, poisons, insecticides, or
any kind of flammable solvent with this
product could result in serious injury or
death.
• Do not spray acids, gasoline, kerosene,
or any other flammable materials with this
product. Use only household detergents,
cleaners and degreasers recommended
for use with pressure washers.
• Wear protective clothing to protect
eyes and skin from contact with sprayed
materials.

7- ENG
WARNING: RISK OF BURSTING
WHAT CAN HAPPEN HOW TO PREVENT IT
• Over inflation of tires could result in
serious injury and property damage.
• Use a tire pressure gauge to check the
tires pressure before each use and while
inflating tires; see the tire sidewall for the
correct tire pressure.
NOTE: Air tanks, compressors and similar
equipment used to inflate tires can fill small
tires similar to these very rapidly. Adjust
pressure regulator on air supply to no more
than the rating of the tire pressure. Add air
in small increments and frequently use the
tire gauge to prevent over inflation.
• High-velocity fluid spray directed at
pneumatic tire sidewalls (such as
found on automobiles, trailers and
the like) could damage the sidewall
resulting in serious injury.
• On pressure washers rated above
1600 PSI (11032 kPa) use the widest
fan spray (40º nozzle) and keep the
spray a minimum of 8" (20 cm) from the
pneumatic tire sidewall. Do not aim spray
directly at the joint between the tire and
rim.
WARNING: RISK OF HOT SURFACES
WHAT CAN HAPPEN HOW TO PREVENT IT
• Contact with hot surfaces, such as
engine exhaust components, could
result in serious burn.
• During operation, touch only the control
surfaces of the pressure washer. Keep
children away from the pressure washer
at all times. They may not be able to
recognize the hazards of this product.
WARNING: RISK OF INJURY FROM LIFTING
WHAT CAN HAPPEN HOW TO PREVENT IT
• Serious injury can result from
attempting to lift too heavy an object. • The pressure washer is too heavy to be lifted by one person. Obtain assistance
from others before lifting.
SAVE THESE INSTRUCTIONS
FOR FUTURE USE

8- ENG
QUICK SETUP GUIDE
WARNING: To reduce the risk of injury, read the pressure washer instruction
manual and the engine instruction manual before operating pressure washer.
IMPORTANT: Ethanol ShieldTM (sold separately) is a fuel stabilizer that helps
eliminate and prevent ethanol related problems in power equipment. Follow the
instructions on the container and add to the gasoline.
AInstall the
Handle
Slide the handle
assembly onto the
frame and secure with
saddle bolts and knobs.
BAdd/Check Oil
The engine
is shipped
without oil. Before
starting engine, add
the oil provided. Check
oil level prior to each
use. Refer to Engine
Owner’s Manual for
complete procedure.
CAdd Gasoline
In a well
ventilated
outdoor area add fresh,
high quality, unleaded
gasoline with a pump
octane rating of 86 or
higher. Do not overfill.
Wipe up spilled fuel
before starting the
engine. Refer to Engine
Owner's Manual for
complete procedure.
QUICK START GUIDE
DANGER:
• Never run engine indoors or in enclosed, poorly ventilated areas. Engine
exhaust contains carbon monoxide, an odorless and deadly gas.
• Risk of fluid injection and laceration. When using the high-pressure setting,
DO NOT allow the high-pressure spray to come in contact with unprotected
skin, eyes or with any pets or animals. Serious injury will occur.
1Connect Garden
Hose to Pump
Thread the
garden hose to
the pump inlet.
See label #1 on unit.
2Connect High
Pressure Hose
to Pump
Connect the high
pressure hose to
the pump outlet.
See label #2 on unit.
3Connect High
Pressure Hose
to Spray Gun
Thread the other end
of the high pressure
hose to the spray gun.

9- ENG
4Connect Spray
Wand to Spray
Gun
Thread the spray
wand into the end
of the spray gun.
5Connect QC
Nozzles to Spray
Wand
Pull quick connect
coupler back and insert
nozzle. Release quick
connect coupler and
twist nozzle to make sure
it is secure in coupler.
6Turn Water
Faucet
Completely On
Do not run the unit
without water supply
connected and turned on.
Use Cold Water Only.
7Release Air from
System
Release all
air from pump and
high pressure hose by
depressing trigger until a
steady stream of water is
present. Approximately
30 seconds.
30 S
8Verify the Fuel
Switch is in the
ON Position
See label #8 on unit.
9Verify the Engine
Switch is turned
to the ON
Position
See label #9 on unit.
OFF
ON
10 Move the Choke
to the CLOSED
Position
See label #10 on unit.
WARNING: This Guide is not a substitute for reading the operator's manual.
User must read and understand operator's manual before using this product.
11 Pull the Recoil
Starter Grip
Pull the
recoil starter grip to
start the engine.
See label #11 on unit.
12 Move the Choke
to the OPEN
Position
Gradually move
the Choke to the
OPEN Position after
engine starts.
See label #12 on unit.

10- ENG
GET TO KNOW THE PRESSURE WASHER
NOTE: Photographs and line drawings used in this manual are for reference
only and do not represent a specific model.
Compare the illustrations with your unit to familiarize yourself with the location of
various controls and adjustments. Save this manual for future reference.
G
B
E
1
D
H
CK
I
J
A
L
BASIC ELEMENTS OF A PRESSURE WASHER (FIG. 1)
A. High Pressure Pump: Increases the pressure of the water supply.
B. Engine: Drives the high pressure pump. Refer to the Engine Owner's Manual
for location and operation of engine controls.
C. High Pressure Hose: Carries the pressurized water from the pump to the gun
and spray wand.
D. Spray Gun: Connects with spray wand to control water flow rate, direction and
pressure.
E. Quick-Connect Spray Wand: Allows the user to quickly change out high
pressure nozzles. See How To Use Spray Wand instructions in Operation
section.
F. Detergent Siphon Hose (not shown): Feeds cleaning agents into the pump to mix
with the water. See
How To Apply Chemicals/Cleaning Solvents instructions
in
Operation section.
G. Handle

11- ENG
H. Frame
I. Pump Outlet
J. Pump Inlet
K. Quick Connect Nozzles
L. Nozzle Holder
BASIC ELEMENTS OF AN ENGINE
Refer to the Engine Owner's Manual for location and operation of engine controls.
Choke Control: Opens and closes carburetor choke valve.
Starter Grip: Pulling starter grip operates recoil starter to crank engine.
Engine Switch: Enables and disables ignition system.
ASSEMBLY INSTRUCTIONS (FIG. 2–4)
1. Locate and remove all loose parts from the carton.
2. Cut four corners of the carton from top to bottom and lay the panels flat.
3.
Slide the handle assembly (G) onto
G
H
22A K
K
L
L
the frame (H) and secure with saddle
bolts and knobs.
NOTICE: Risk of personal injury. Avoid
placing hands between handle and frame
when assembling to prevent pinching.
4. Remove colored quick connect
nozzles (K) from plastic bag and insert them into the nozzle holder (L).
NOTE: Nozzles are color coded to match colored nozzles on panel.
5. Connect wand (E) to gun (D). Tighten securely.
6. Attach high pressure hose (C) to gun (D). Tighten securely.
E
4
D
C
3
D
NOTICE: The engine is shipped without oil. Before starting engine, add the oil
provided. Damage to the engine will occur if the engine is run without oil, this
damage will not be covered under warranty.
NOTICE: The high-pressure pump was filled with oil at the factory. Always check
oil level before using (refer to Maintenance for more information).

12- ENG
OPERATION
PRESSURE WASHER TERMINOLOGY
PSI: Pounds per Square Inch. The unit of measure for water pressure. Also used
for air pressure, hydraulic pressure, etc.
GPM: Gallons Per Minute. The unit of measure for the flow rate of water.
CU: Cleaning Units. GPM multiplied by PSI equals CU.
Bypass Mode: Allows water to re-circulate within the pump when the gun trigger is
not pulled. This feature allows the operator to release the trigger gun and reposition
themselves without having to turn the engine off in between cleaning actions.
WARNING: Do not allow the unit to run for more than two minutes without
the gun trigger being pulled. This could cause overheating and damage to
the pump. When the temperature inside the pump rises too high, the thermal
relief valve will open and release a spray of water from the pump to lower the
internal temperature. The valve will then close.
Thermal Relief Valve (M, Fig. 5): When the temperature inside the 5
M
pump rises too high, this valve will open and release a gush of
water in an effort to lower the temperature inside the pump. The
valve will then close.
Detergent Injection System: Mixes cleaners or cleaning solvents
with the water to improve cleaning effectiveness.
Water Supply: All pressure washers must have a source of water.
The minimum requirements for a water supply are 20 PSI and 5 Gallons Per Minute.
If your water source is a well, the garden hose length can only be 30ft. (9m) max.
WARNING: To reduce the possibility of contamination always protect
against backflow when connected to a potable water system.
PRESSURE WASHER OPERATING FEATURES
PRESSURE ADJUSTMENTS (FIG. 6)
The pressure setting is preset at the factory to achieve optimum pressure and
cleaning. If you need to lower the pressure, it can be accomplished by these
methods.
1. Back away from the surface to be cleaned. The further away you are, the less
the pressure will be on the surface to be cleaned.
2. Change to the 40˚ nozzle (white). This nozzle delivers a less powerful stream
of water and a wider spray pattern. Refer to How To Use Spray Wand.
3. This pressure washer's high pressure pump is equipped with an adjustable
unloader feature that allows the pressure setting to be adjusted.
To lower the pressure, turn the pressure control knob on the pump counter-
clockwise to the desired pressure.
To return the pump pressure to the factory setting, turn the pressure control
knob on the pump clockwise until it stops.
-
+
6

13- ENG
NOTICE: DO NOT try to tum pressure regulator knob past the built-in stop or dam-
age to the pump will result.
NOTICE: DO NOT overtighten the pressure control knob. If overtightened the knob
COULD break and result in immediate loss of water pressure and costly repairs to
the unit.
NOTICE: DO NOT attempt to increase pump pressure. A higher pressure setting
than the factory set pressure may damage pump.
HOW TO USE SPRAY WAND
The nozzles for the spray wand are stored in the nozzle holder on the panel assembly.
Colors on the panel identify nozzle spray pattern. Refer to the following chart to
choose the correct nozzle for the job to be performed.
NOZZLE COLOR SPRAY PATTERN USES SURFACES*
Red
0˚ powerful pinpoint for
spot cleaning of hard,
unpainted surfaces or
for high reach areas
unpainted metal
or concrete;
DO NOT use on wood
Yellow
15˚ intense cleaning
of unpainted
hard surfaces
grills, driveways,
concrete or brick
walkways, unpainted
brick or stucco
Green
25˚ standard clean-
ing nozzle for most
applications
yard tools, sidewalks,
lawn furniture,
unpainted siding,
stucco, gutters and
eaves, concrete,
brick surfaces
White
40˚ cleaning of painted
or delicate surfaces auto/RV, marine, wood, painted brick
and stucco, vinyl,
painted siding
Black
low pressure applies cleaning
solutions Low pressure spray is safe on all
surfaces. Always
verify compatibility
of cleaning solution
prior to use.
*NOTICE: The high pressure spray from your pressure washer is capable of
causing damage to surfaces such as wood, glass, automobile paint, auto striping
and trim, and delicate objects such as flowers and shrubs. Before spraying, check
the item to be cleaned to assure yourself that it is strong enough to resist damage
from the force of the spray.
CHANGING NOZZLES ON SPRAY WAND (FIG. 7)
DANGER: Risk of fluid injection. Do not direct discharge stream toward
persons, unprotected skin, eyes or any pets or animals. Serious injury will
occur.

14- ENG
WARNING: Flying objects could cause risk of serious 7
KE
injury. Do not attempt to change nozzles while pressure
washer is running. Turn engine off before changing
nozzles.
1. Pull quick-connect coupler (E) back and insert nozzle
(K).
2. Release quick-connect coupler and twist nozzle to
make sure it is secure in coupler.
WARNING: Flying object could cause risk of serious injury. Ensure nozzle
is completely inserted in quick-connect socket and quick-connect collar is
fully engaged (forward) before squeezing gun trigger.
HOW TO APPLY CHEMICALS/CLEANING SOLVENTS (FIG. 8)
Applying chemicals or cleaning solvents is a low pressure operation. NOTE: Use
only soaps and chemicals designed for pressure washer use. Do not use bleach.
To Apply Chemicals:
1. Ensure detergent siphon hose (F, Figure 8) is attached
F
8
to barbed fitting location near high pressure hose
connection of pump as shown.
2. Place other end of detergent siphon hose with
filter on it into container holding chemical/cleaning
solution. NOTE: For every 7 gallons of water pumped
1 gallon of chemical/cleaning solution will be used.
3. Install low pressure (black) nozzle into quick connect fitting of spray wand, see
How To Use Spray Wand paragraph in this section.
4. After use of chemicals, place detergent siphon hose into container of clean
water and draw clean water through chemical injection system to rinse system
thoroughly. If chemicals remain in the pump, it could be damaged. Pumps
damaged due to chemical residue will not be covered under warranty.
NOTE: Chemicals and soaps will not siphon if the black soap nozzle is not installed
on the spray wand.
STARTING (FIG. 9–12)
WARNING: To reduce the risk of injury, read the pressure washer instruction
manual and the engine instruction manual before starting pressure washer.
DANGER: Risk of fluid injection and laceration. When using the high
pressure setting, DO NOT allow the high pressure spray to come in contact
with unprotected skin, eyes, or with any pets or animals. Serious injury will
occur.
• Your washer operates at fluid pressures and velocities high enough to penetrate
human and animal flesh, which could result in amputation or other serious injury.
Leaks caused by loose fittings or worn or damaged hoses can result in injection
injuries. DO NOT TREAT FLUID INJECTION AS A SIMPLE CUT! See a physician
immediately!
DANGER: Carbon Monoxide. Using an engine indoors can kill you in
minutes. Engine exhaust contains high levels of carbon monoxide (CO), a
poisonous gas you cannot see or smell. You may be breathing CO even if you
do not smell engine exhaust.
• Breathing exhaust fumes will cause serious injury or death! Engine exhaust
contains carbon monoxide, an odorless and deadly gas.

15- ENG
• Operate pressure washer in a well-ventilated area. Avoid enclosed areas
such as garages, basements, etc.
• Never operate unit in or near a location occupied by humans or animals.
WARNING: Risk of Fire, Asphyxiation and Burn. Never fill fuel tank when
engine is running or hot. Do not smoke when filling fuel tank.
• Never fill fuel tank completely. Fill tank to 1/2" (12.7 mm) below bottom of filler
neck to provide space for fuel expansion. Wipe any fuel spillage from engine and
equipment before starting engine.
• DO NOT let hoses come in contact with very hot engine muffler during or
immediately after use of your pressure washer. Damage to hoses from contact with
hot engine surfaces will NOT be covered by warranty.
NOTICE: Risk of property damage. Never pull water supply hose to move pressure
washer. This could damage hose and/or pump inlet.
• DO NOT use hot water, use cold water only.
• Never turn water supply off while pressure washer engine is running or damage to
pump will result.
• DO NOT stop spraying water for more than two minutes at a time. Pump operates
in bypass mode when spray gun trigger is not pressed. If pump is left in bypass
mode for more than two minutes internal components of the pump can be
damaged.
If you do not understand these precautions, please contact our customer service
department at www.simpsoncleaning.com
Prior to starting, refer to your engine manual for proper starting procedure.
1. In a well ventilated outdoor area add fresh, high quality, unleaded gasoline
with a pump octane rating of 86 or higher. Do not overfill. Wipe up spilled
fuel before starting the engine. Refer to Engine Owner's Manual for correct
procedure.
IMPORTANT: Ethanol ShieldTM (sold separately) is a fuel stabilizer that helps
eliminate and prevent ethanol related problems in power equipment. Follow the
instructions on the container and add to the gasoline.
NOTICE: Use of fuels with greater than 10% ethanol are
not approved for use in this product per EPA regulations
and will damage the unit and void the warranty.
2. Check engine oil level. Refer to Engine Owner's Manual for correct procedure.
3. Check pump oil level. The oil level should come to the dot in the middle of the
sight glass. Refer to the Pump paragraph under Maintenance.
4. Connect the water hose to the water source. Turn the water source on to
remove all air from the hose. When a steady stream of water is present, turn
the water source off.
5. Verify the filter screen (O) is in water inlet of pump. NOTE: Convex side faces
out.
I
11
C
10
N
J
O
9

16- ENG
6. Connect water source (N) to pump inlet (J). NOTE: Water source must provide
a minimum of 5 gallons per minute at 20 PSI.
7. Connect
high pressure hose (C) to pump outlet (I).
WARNING: To reduce the possibility of contamination always protect
against backflow when connected to a potable water system.
8. Choose the correct nozzle for the job to be performed. See How To Use spray
Wand instructions in this section. NOTE: If applying a chemical or cleaning
solution, see How To Apply Chemicals/Cleaning Solvents instructions in this
section.
9. Turn water source on.
NOTICE: Risk of property damage. Failure to do so could cause damage to the
pump.
10. Remove all air from the pump and high pressure hose by depressing trigger
until a steady stream of water is present.
11. Start engine. See Engine Owner's Manual for correct procedure.
WARNING: Risk of unsafe operation. If engine does not start after two
pulls, squeeze trigger of gun to relieve pump pressure. Pull starter cord slowly
until resistance is felt. Then pull cord rapidly to avoid kickback and prevent
hand or arm injury.
NOTE: If the oil level in the engine is low, the engine will not start. If the engine does
not start, check the oil level and add oil as needed.
12. Depress trigger on gun to start water flow.
WARNING: Do not allow the unit to run for more than two minutes without
the gun trigger being pulled. This could cause overheating and damage to
the pump. When the temperature inside the pump rises too high, the thermal
relief valve will open and release a spray of water from the pump to lower the
internal temperature. The valve will then close.
WARNING: Risk of unsafe operation. Stand on a stable surface and
grip gun/spray wand firmly with both hands. Expect the gun to kick when
triggered.
13. Release trigger to stop water flow.
WARNING: Risk of injury from spray. Always engage the
12
P
trigger lock (P) when gun is not in use. Failure to do so could
cause accidental spraying.
SHUTTING DOWN
1. After each use, if you have applied chemicals, place
detergent siphon hose into container of clean water and draw clean water
through chemical injection system to rinse system thoroughly.
NOTICE: Risk of property damage. Failure to do so could cause damage to the
pump.
2. Turn engine off. See Engine Owner's Manual.
NOTICE: Risk of property damage. NEVER turn the water off with the engine
running.
3. Turn water source off.

17- ENG
4. Pull trigger on spray gun to relieve any water pressure in hose or spray gun.
NOTE: Failure to release system pressure will prevent removal of high pressure
hose from spray gun or pump connection.
5. See Storage section in this manual for proper storage procedures.
MAINTENANCE
WARNING: Risk of burn hazard. When performing maintenance, you may
be exposed to hot surfaces, water pressure or moving parts that can cause
serious injury or death.
WARNING: Risk of fire hazard. Always disconnect, spark plug wire,
let the engine cool and release all water pressure before performing any
maintenance or repair. The engine contains flammable fuel. Do not smoke or
work near open flames while performing maintenance.
To ensure efficient operation and longer life of your pressure washer, a routine
maintenance schedule should be prepared and followed. If the pressure washer is
used in unusual conditions, such as high-temperatures or dusty conditions, more
frequent maintenance checks will be required.
ENGINE
Consult the Engine Owner's Manual for the manufacturer's recommendations
for any and all maintenance. NOTE: The engine drain plug is located at the rear of
the unit.
PUMP (FIG. 13)
NOTE: The Pump was filled with oil at the factory. The preferred oil is SIMPSON®
Premium Pump Crankcase Oil. If this oil is not available, an SAE 15W-40 oil may
be used. Change the pump oil after the first 50hours of operation and every 100
hours thereafter, or every 3 months.
TO CHECK OIL
The oil level should come to the dot in the middle of the sight glass (AA).
HOW TO CHANGE PUMP OIL
1. Loosen pump oil fill plug (BB).
2. Place a container under the pump oil drain 13 BB
AA
CC
plug (CC).
3. Remove pump oil drain plug.
4. After oil is drained, replace pump oil drain
plug. Tighten securely.
5. Refill pump using SIMPSON®Premium Pump
Crankcase Oil. If this oil is not available, an
SAE 15W-40 oil may be used.
6. Replace pump oil fill plug and tighten securely.
If there is a problem with the pump contact us at www.simpsoncleaning.com
CONNECTIONS
Connections on pressure washer hoses, gun and spray wand should be cleaned
regularly and lubricated with light oil or lithium grease to prevent leakage and
damage to the o-rings.

18- ENG
NOZZLE CLEANING (FIG. 14)
If the nozzle becomes clogged with foreign materials, such as dirt, excessive
pressure may develop. If the nozzle becomes partially clogged or restricted, the
pump pressure will pulsate. Clean the nozzle immediately using the nozzle kit
supplied and the following instructions:
1. Shut off the pressure washer and turn off the water supply.
2. Pull trigger on gun handle to relieve any water pressure.
3. Disconnect the spray wand from the gun.
4. Remove the high pressure nozzle (K) from the spray 14 K
K
N
wand. Remove any obstructions with the nozzle cleaning
tool provided and backflush with clean water.
5. Direct water supply (N) into nozzle to backflush loosened
particles for 30 seconds.
6. Reassemble the nozzle to the wand.
7. Reconnect spray wand to gun and turn on water supply.
8. Start pressure washer and place spray wand into high
pressure setting to test.
CLEAN THE WATER INLET FILTER (FIG. 9)
This screen filter should be checked periodically and cleaned if necessary.
1. Remove filter by grasping end and removing it from water inlet of pump.
2. Clean filter by flushing it with water on both sides.
3. Re-insert filter into water inlet of pump. NOTE: Convex side faces out.
NOTE: Do not operate the pressure washer without filter properly installed.
STORAGE
ENGINE
Consult the Engine Owner's Manual for manufacturer’s recommendations for
storage.
TO PREVENT FUEL-RELATED PROBLEMS
1. Add Ethanol ShieldTM fuel stabilizer following the manufacturer’s instructions.
When adding a gasoline stabilizer, fill the fuel tank with fresh gasoline. If only
partially filled, air in the tank will promote fuel deterioration during storage.
If you keep a container of gasoline for refueling, be sure that it contains only
fresh gasoline.
2. After adding a gasoline stabilizer, run the engine outdoors for 10 minutes
to be sure that treated gasoline has replaced the untreated gasoline in the
carburetor.
3. Turn the fuel valve to the OFF position.
4. Continue to run the engine until it stops from the lack of fuel in the carburetor
fuel bowl. Running time should be less than 3 minutes.
PUMP
The manufacturer recommends using SIMPSON®/ POWERWASHER®Pump
Guard or equivalent when storing the unit for more than 30 days and/or when
freezing temperatures are expected. SIMPSON®/ POWERWASHER® Pump Guard
is environmentally friendly.

19- ENG
NOTE: Using pump guard helps provide proper lubrication to the internal seals of
the pump regardless of temperature or environment.
NOTICE: Risk of property damage. Use only SIMPSON®/ POWERWASHER®
Pump Guard or equivalent. Other products could be corrosive and/or contain alco-
hol which may cause pump damage.
1. Turn off pressure washer and disconnect hoses from pump.
2. Unscrew bottle valve from Pump Guard bottle and remove seal.
3. Screw bottle valve back onto bottle.
4. Attach bottle to water inlet of pump.
5. Squeeze bottle to inject contents into pump.
6. With ignition switch off, simultaneously pull starter rope and squeeze bottle.
Repeat until protector fluid exits pump outlet. NOTE: This step may require
two people.
PRESSURE WASHER
1. Drain all water from high pressure hose and wrap it onto hose wrap.
2. Drain all water from the spray gun and wand by holding spray gun in a vertical
position with nozzle end pointing down and squeezing trigger. Store in gun
holder.
3. Wrap up and secure detergent siphon hose so it is protected from damage.
ACCESSORIES
DANGER: Risk of fluid injection. When using replacement spray wands or
guns with this pressure washer, DO NOT use a spray wand and/or spray gun/
wand combination that is shorter in length than what was provided with this
pressure washer as measured from the nozzle end of the wand to the gun
trigger.
NOTICE: The use of any other accessory not recommended for use with this tool
could be hazardous. Use only accessories rated equal to or greater than the rating
of the pressure washer.
SPECIFICATIONS
MODEL ALH3425
PSI Max* 3400 PSI
GPM Max* 2.5 gpm
High Pressure Hose 35 ft. (10.67 m)
Presure of Inlet Water 20–100 PSI
Inlet Water cold tap (100 °F max)
Soap Consumption Rate 10% max
* Rated Pressure and Rated Water Flow is within manufacturing tolerance of
(+/- 10%).
In a continued commitment to improve quality, the manufacturer reserves the right
to make component changes, design changes, or specification changes when
necessary and without notice.

20- ENG
SERVICE INFORMATION
Do not return this product to your retailer. Please contact our customer service
department at www.simpsoncleaning.com
LIMITED WARRANTY
The manufacturer of this product agrees to repair or replace designated parts that
prove defective within the warranty period listed below at the manufacturer’s sole
discretion. Specific limitations/extensions and exclusions apply.
This warranty covers defects in material and workmanship and not parts failure
due to normal wear, depreciation, abuse, accidental damage, negligence, improper
use, maintenance, water quality or storage. To make a claim under the terms of the
warranty, all parts said to be defective must be retained and available for return
upon request to a designated Warranty Service Center for warranty inspection. The
judgments and decisions of the manufacturer concerning the validity of warranty
claims are final.
These warranties pass through to the end user and are non-transferable. As a
factory authorized and trained Warranty Service Center, the factory will honor the
terms of all component warranties and satisfy claims of the appropriate warranty
provisions.
Normal wear items include, but are not limited to, valves and seals, which are not
covered by this warranty.
This warranty replaces all other warranties, express or implied, including without
limitation any warranties of merchantability or fitness for a particular purpose and
all such warranties are hereby disclaimed and excluded by the manufacturer. The
manufacturer’s warranty obligation is limited to repair and replacement of defective
products as provided herein and the manufacturer shall not be liable for any
further loss, damages, or expenses – including damages from shipping, accident,
abuse, acts of God, misuse, or neglect. Neither is damage from repairs using parts
not purchased from the manufacturer or alterations performed by non-factory
authorized personnel. Failure to install and operate equipment according to the
guidelines put forth in the instruction manual shall void warranty.
This warranty does not cover the following: machines used for rental purposes,
damage resulting from shipping (claims must be filed with freighter), accident,
abuse, act of God, misuse, or neglect. Neither is damage from repairs or
alterations performed by non-factory authorized personnel or failure to install and
operate equipment according to the guidelines put forth in the instruction manual.
The manufacturer will not be liable to any persons for consequential damage, for
personal injury, or for commercial loss.
WARRANTY DOES NOT APPLY TO FAILURES DUE TO:
• Freight damage
• Damage due to chemical deterioration, scale build up, rust, corrosion or
thermal expansion
• Freeze damage
• Damage caused by parts or accessories not obtained from an authorized
dealer or not approved by the manufacturer.
• Normal wear of moving parts or components affected by moving parts.
ENGINE
Covered by engine manufacturer warranty. See engine manual.