Power Fist 420cc User manual

V 4.4 8449019
Please read and understand all instructions before use. Retain this manual for
future reference.
420cc OHV Gas Engine
with Electric Start
User Manual

8449019 420cc OHV Gas Engine with Electric Start V 4.4
2 For technical questions call 1-800-665-8685
SPECIFICATIONS
Engine Displacement
420cc
Start Type
Pull/12V DC
Torque
19.54 ft-lb
Shaft Diameter
1 in.
Shaft Rotation (From PTO Shaft Side)
Counterclockwise
Shaft End Tapped [Diameter (in) / Threads Per Inch]
3/8 -24 UNF
Number of Cylinders 1
Cylinder Bore
3.5 in.
Stroke
2.6 in.
Compression Ratio
8.5:1
Cooling System
Air
Fuel Tank
Metal
Fuel Type
Gasoline
Fuel Tank Capacity
7 quarts (6.6 litres)
Fuel Filter
Yes
Oil Capacity
1.1 quarts (1 litre )
Lubrication System
Splash
Oil API Service Classification
SF or Newer
Low Oil Shutdown
Yes
Governor System
Mechanical
Ignition System
Transistorized Magneto
Max. Speed
3,600 RPM
Spark Plug (SKU 4780112)
Gap
0.028~0.03 in. (0.7~0.8 mm)
Torque
18~22 Nm
Air Cleaner Type
Foam
420cc OHV Gas Engine
with Electric Start

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INTRODUCTION
The 420cc OHV gas engine is ideal for commercial or agricultural applications. The
engine has an overhead valve design and electronic ignition for easy starts,
increased power and better fuel economy. It meets all Environmental Protection
Agency (EPA) Guidelines.
Common applications are pressure washers, tillers/cultivators, log splitters, forestry
equipment, water pumps, lawn and garden equipment, agricultural equipment
and generators.
SAFETY
WARNING! Read and understand all instructions before using this engine. The
operator must follow basic precautions to reduce the risk of personal injury
and/or damage to the equipment.
Keep this manual for safety warnings, precautions, operating or inspection and
maintenance instructions.
HAZARD DEFINITIONS
Please familiarize yourself with the hazard notices found in this manual. A notice is
an alert that there is a possibility of property damage, injury or death if certain
instructions are not followed.
DANGER! This notice indicates an immediate and specific hazard that will
result in severe personal injury or death if the proper precautions
are not taken.
WARNING! This notice indicates a specific hazard or unsafe practice that could
result in severe personal injury or death if the proper precautions
are not taken.
CAUTION! This notice indicates a potentially hazardous situation that may result
in minor or moderate injury if proper practices are not taken.
NOTICE! This notice indicates that a specific hazard or unsafe practice will
result in equipment or property damage, but not personal injury.

8449019 420cc OHV Gas Engine with Electric Start V 4.4
4 For technical questions call 1-800-665-8685
WORK AREA
1. Operate in a safe work environment. Keep your work area clean, well lit and
free of distractions.
2. Keep anyone not wearing the appropriate safety equipment away from the
work area.
3. Store unused tools properly in a safe and dry location to prevent rust or
damage. Lock tools away and keep out of the reach of children.
4. Do not install or use the engine in the presence of flammable gases, dust
or liquids.
PERSONAL SAFETY
WARNING! Wear personal protective equipment approved by the Canadian
Standards Association (CSA) or American National Standards Institute (ANSI).
PERSONAL PROTECTIVE EQUIPMENT
1. Always wear impact safety goggles that provide front and side protection for
the eyes. Eye protection equipment should comply with CSA Z94.3-07 or ANSI
Z87.1 standards based on the type of work performed.
2. Wear gloves that provide protection based on the work materials or to reduce
the effects of tool vibration.
a. Do not wear gloves when operating a tool that can snag the material and
pull the hand into the tool.
3. Wear protective clothing designed for the work environment and tool.
4. Non-skid footwear is recommended to maintain footing and balance in the
work environment.
5. Wear steel toe footwear or steel toe caps to prevent a foot injury from
falling objects.
PERSONAL PRECAUTIONS
Control the tool, personal movement and the work environment to avoid personal
injury or damage to tool.

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1. Do not operate any tool when tired or under the influence of drugs, alcohol
or medications.
2. Avoid wearing clothes or jewelry that can become entangled with the moving
parts of a tool. Keep long hair covered or bound.
3. Do not overreach when operating a tool. Proper footing and balance enables
better control in unexpected situations.
SPECIFIC SAFETY PRECAUTIONS
WARNING! DO NOT let comfort or familiarity with product (gained from repeated
use) replace strict adherence to the engine safety rules. If you use this engine
unsafely or incorrectly, you can suffer serious personal injury.
NOTICE! This engine is designed for recreational and light farm use. It is not
intended for heavy industrial use, in aircraft products or vehicles in competitive
events. These uses may shorten the engine’s useful life span.
1. Use the correct engine for the job. This engine was designed for a specific
function. Do not modify or alter this engine or use it for an unintended purpose.
2. All users must understand the operation of all controls and learn how to stop
the engine quickly in case of emergency.
3. Do not tamper with governor spring, links or other engine parts to increase
speed or power.
4. The engine and exhaust become very hot during operation. Severe thermal
burns can occur on contact, especially with the muffler.
a. Keep the engine at least 3 feet (1 meter) away from buildings and other
equipment during operation.
b. Remove accumulated debris from muffler and cylinder area. Combustible
debris, such as leaves, grass, brush, etc. can catch fire if they come in
contact with a hot engine.
c. Do not place anything on the engine while it is running.
d. Allow muffler, engine cylinder and fins to cool before touching.

8449019 420cc OHV Gas Engine with Electric Start V 4.4
6 For technical questions call 1-800-665-8685
CARBON MONOXIDE POISONING
WARNING! Never operate a gas engine indoors or in a confined space as the
exhaust contains carbon monoxide gas. Inhalation of carbon monoxide gas can
lead to illness or death. The area must be well ventilated. Opening windows and
doors is not enough to ventilate an area.
Carbon monoxide is a colourless and odourless gas that is difficult to detect.
Carbon monoxide poisoning results from inhalation of the gas and may be lethal if
left untreated. Evacuate all people to an area with clean air and seek immediate
medical attention for any person experiencing the following symptoms:
1. Headache
2. Confusion
3. Shortness of breath
4. Weakness
5. Chest Pain
6. Dizziness
7. Blurred Vision
8. Nausea and vomiting
9. Unconsciousness
BATTERY PRECAUTIONS
WARNING! Do not charge a damaged or frozen battery. Contact your local
municipality for proper disposal procedures.
CAUTION! Only charge a battery with a charger designed for that purpose.
Do not use modified chargers or a charger that does not specify the voltage,
amperage or recharge rate. Improper charging can lead to battery rupturing.
1. Lead-acid batteries generate oxygen and hydrogen. These gases can be
explosive. Keep batteries well ventilated. Remove any source of ignition
such as an open flame or a device like a heater from the area. Sparks may
also ignite the gas.
2. Lead batteries contain sulfuric acid, also referred to as electrolyte or
battery acid. The acid is corrosive and can cause a skin burn if leaking or
splashed. The acid may also pose a threat if inhaled or ingested
accidentally. The acid can destroy normal clothing and injure the flesh
underneath. Wear splash-proof goggles and protective clothing when
handling a battery.

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3. Even a discharged battery may still carry a charge. To prevent a shock,
place battery terminal caps or covers over the terminal to prevent
accidental contact. Hold the battery by the bottom if moving the battery to
a different location.
4. Batteries are heavy due to the weight of the lead and liquid contained
inside. A lead-acid battery could weigh upwards of 50-60 lbs. Use safe
lifting methods if moving the battery.
UNPACKING
WARNING! Do not operate the engine if any part is missing. Replace the missing
part before operating. Failure to do so could result in a malfunction and
personal injury.
Remove the parts and accessories from the packaging and inspect for damage.
Make sure that all items in the parts list are included.
Contents:
• Gas Engine
• Spark Plug Wrench

8449019 420cc OHV Gas Engine with Electric Start V 4.4
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IDENTIFICATION KEY
When this manual refers to a letter, it corresponds to the components shown in
Figure 1. Compare the illustration with your engine to familiarize yourself with the
location of various features and controls.
A Muffler
B Air Cleaner
C Spark Plug
D Throttle Lever
E Choke Lever
F Fuel Valve
G Starting Handle/
Recoil Starter
H Drain Plug
I Fuel Filler Cap
J Fuel Tank
K Pipe
L Starting Motor
M Engine Switch
N Breaker
O Dipstick/Oil Filler Cap
P Starting Motor
Cables
ASSEMBLY & INSTALLATION
References to the Parts List are represented by the pound symbol (#).
References to the Parts Identification are represented by a letter (A).
1. The engine comes assembled.
2. The engine is not shipped with oil. Starting the engine without oil will damage
the engine beyond repair. Add oil per the maintenance instructions.
3. Check that the filter is in place. See Maintenance – Service the Air Filter
CONNECTING THE BATTERY
NOTICE! Do not reverse the polarity when connecting the battery as as this
will short circuit the battery charging system or damage the equipment.
Fig. 1

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The engine has an electric start option that requires a 12 volt battery (sold-
separately). Use a 12V battery with a rating of at least 18 ampere-hours with
the engine.
The engine has two battery cables with copper lugs. The polarity of each cable
is displayed on a rubber cover where they connect on either side of the starter
motor (Fig. 2-2).
1. Remove the wing nuts from the battery’s
positive (+) and negative (-) terminals.
2. Slide the positive battery cable lug
(Fig. 2-3) onto the positive terminal. Coat
the cable end with grease and reattach the
wing nut. Tighten hand-tight.
3. Slide the negative battery cable lug
(Fig. 2-1) onto the negative terminal. Coat
the cable end with grease and reattach the
wing nut. Tighten hand-tight.
4. Secure the battery so it won’t move
while the engine is in use.
OPERATION
BEFORE STARTING THE ENGINE
WARNING! Do not start or run engine in an enclosed area, even if the doors or
windows are open. Engine exhaust contains carbon monoxide (see Carbon
Monoxide Precautions).
1. Make sure spark plug (C), muffler (A), fuel cap (I) and air cleaner (B) are in
place and secured.
2. Ensure the spark plug lead is securely connected to the spark plug, otherwise
unintentional sparking can result, causing a fire or electric shock.
3. Check that all protective covers and guards are in place.
4. Check that all nuts, bolts and screws are tight.
Fig. 2
2-1
2-2
2-3

8449019 420cc OHV Gas Engine with Electric Start V 4.4
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5. Check the fuel level.
6. Check the engine oil level. Running the engine without enough oil can damage
the engine.
7. Look around and underneath the engine for signs of oil or gasoline leaks.
a. Do not start the engine until any spilled fuel has evaporated.
8. Remove any excessive dirt or debris, especially around the muffler (A) and
recoil starter (G).
9. Look for signs of damage.
10. Check the equipment powered by this engine.
11. Review the instructions provided with the equipment powered by this engine for
precautions and procedures that should be followed before starting the engine.
STARTING THE ENGINE
WARNING! Direct-coupled equipment components such as, but not limited to,
blades, impellers, pulleys, sprockets, etc., must be securely attached before
the engine is started to avoid injury or damage.
CAUTION! Failure to follow the steps below will result in rapid retraction of the
starter cord faster than the user can let go. This will pull the user’s hand and
arm toward the engine, possibly resulting in an injury.
1. Move the fuel valve (F) to the ON position.
2. Move the choke lever (E) to the CLOSED position if the engine is cold. The
choke is unnecessary when restarting a warm engine.
3. Move the throttle lever (D) away from MIN. position, about 1/3 of way toward
the MAX. position.
4. Turn the engine switch (M) to the ON position.
5. Pull Start - Pull the starter handle (G) lightly until you feel resistance, then pull
the starter handle briskly. The engine should turn over and start running.
a. Do not allow the starter handle to snap back against the engine.
Instead, return the starter grip gently by hand.

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6. Electric Start – Attach the battery (see Assembly & Installation -
Connecting the Battery). Turn the key to the start position and hold it there
until the engine starts. If engine fails to start within 5 seconds, release the
key and wait at least 10 seconds before operating the starter again.
7. If the engine floods, set the choke to the OPEN/RUN position, place the
throttle in FAST and attempt to start the engine again.
8. If the choke lever was moved to the CLOSED position to start the engine,
gradually move it to the OPEN position as the engine warms up.
The engine may make a metallic rapping noise (spark knock, ping) while running
under a heavy load. This is normal. Replace the fuel with premium quality gasoline
if the metallic rapping noise continues under normal load. Contact a qualified
mechanic if the pinging continues as this may indicate existing engine damage.
STOPPING THE ENGINE
CAUTION! Do not choke carburetor to stop engine.
IN AN EMERGENCY
Turn the engine switch (M) to the OFF position to stop the engine.
DURING NORMAL USE
Stop the engine by following this procedure:
1. Move the throttle lever (D) to the MIN. position.
2. Turn the engine switch (M) to the OFF position.
3. Turn the fuel valve (F) to the OFF position.
CARE & MAINTENANCE
WARNING! Always ensure that the engine is off before you begin any
maintenance or repairs. An active engine part can cause a severe injury,
amputation or death if a mishap occurs.

8449019 420cc OHV Gas Engine with Electric Start V 4.4
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The following section includes a maintenance schedule, routine inspection
procedures and simple maintenance procedures using basic hand tools. Service
tasks that are more difficult or require special tools are best handled by a technician
or other qualified mechanic.
1. Maintain the engine with care. A well-maintained engine is more efficient and
less likely to have problems.
2. Follow instructions for servicing.
3. Inspect the engine components periodically. Check fuel lines, tank, cap and
fittings frequently for cracks or leaks. Have damaged or worn components
repaired or replaced by an authorized technician.
4. Replacement parts must match the original. Use manufacturer recommended
parts when possible.
5. Disconnect the spark plug lead and keep it away from the spark plug during
maintenance and repairs.
a. Disconnect the negative battery lead, then the positive lead.
6. Maintain the engine’s label and name plate. These carry important information.
If unreadable or missing, contact Princess Auto Ltd. for replacements.
IMPORTANT! Only qualified service personnel should repair the engine.

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MAINTENANCE SCHEDULE
This schedule applies to normal operating conditions. If you operate your engine
under severe conditions, such as sustained high-load or high-temperature
operation or use in unusually wet or dusty conditions, consult a qualified technician
for recommendations applicable to your individual needs and use.
Regular Service Period *
Before Each Use/Daily
First Month or 20 Hours
Every 3 months or 50 Hours
Every 6 months or 100 Hours
Every Year or 300 Hours
Performed at every indicated month
or operating hour interval, whichever
comes first.
Engine Oil
Check
X
Change
X
X
Air Cleaner
Check
X
Clean
X **
Sediment Cup
Clean
X
Spark Plug Clean / Adjust X
Replace
X
Idle Speed
Check / Adjust
X
Valve Clearance
Check / Adjust
X
Combustion Chamber
Clean
After every 500 Hours
Fuel Tank and Filter
Clean
X
Fuel Tube
Check
Every 2 years (replace if necessary)
* For commercial use, log hours of operation to determine proper maintenance intervals.
** Service more frequently when used in dusty areas.
FUEL RECOMMENDATIONS
NOTICE! Do not use unapproved gasoline, such as E85. Do not mix oil in
gasoline or modify the engine to run on alternate fuels. This can damage the
engine components. To protect the fuel system from gum formation, mix a
fuel stabilizer into the fuel.
This engine is certified to operate on unleaded gasoline with a minimum of
87 octane/87 AKI (91 RON). Use gasoline without ethanol or similar alcohol
based additives. Gasoline with up to 10% ethanol (gasohol) or up to 15% MTBE
(methyl tertiary butyl ether) may be used if required.

8449019 420cc OHV Gas Engine with Electric Start V 4.4
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If the engine is routinely operated at altitudes over 5,000 ft (1,524 meters), it will be
necessary to have a qualified technician modify the engine for increased
performance. Fuel should be a minimum of 85 octane/85 AKI (91 RON) to prevent
decreased performance.
The emissions control system for this engine is EM (Engine Modifications).
1. Use only an approved fuel container for refueling the engine.
2. Store fuel out of direct sunlight in a cool and dry location.
3 Inspect container for fuel leaks. Replace any container that leaks.
4. You may occasionally hear a light spark knock or pinging (metallic rapping
noise) while the engine is operating under heavy loads. This is no cause for
concern. If spark knock or pinging occurs at a steady engine speed under
normal load, switch to a premium gasoline or change brands of gasoline. If
spark knock or pinging persists, see an authorized repair centre.
5. Never use stale or contaminated gasoline or an oil/gasoline mixture designed
for two-stroke motors.
HOW TO ADD FUEL
DANGER! Fuel is very flammable. Use extreme care when handling or storing
fuel. An ignition source contacting the fumes or fuel may result in a fire or
explosion and cause fatal or serious injuries to you or a bystander.
1. Refuel outdoors or in a well-ventilated area and immediately wipe up spills.
Fuel can damage paint and plastic.
2. Stop the engine and position equipment on a level surface.
3. Let engine cool at least 2 minutes before removing the fuel cap.
4. Clean the fuel cap (I) area of dirt and debris. Do not allow dirt or water to enter
the fuel tank.
5. Remove the fuel cap slowly to allow the pressure to equalize.
6. Check the fuel level.

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7. Add fuel until it reaches the bottom
of the metal collar supporting the
fuel strainer in the fuel tank
(Fig. 3-1). Take care to not overfill
the tank. It may be necessary to
lower the fuel level depending on
operating conditions.
8. Reinsert the fuel tank cap and tighten.
9. Wipe up any spilled fuel before starting the engine or allow to evaporate.
Spilled fuel is both a fire hazard and an environmental hazard. Dispose of the
fuel soaked rags in a proper hazardous waste container.
ENGINE OIL
NOTICE! Engine oil is a major factor affecting engine performance and service
life. Non-detergent and 2-stroke engine oils will damage a 4-stroke engine and
are not recommended.
High-quality detergent engine oils are acceptable if the (API) performance rating is
SF, SG, SH, SJ or higher. Always check the API service label on the oil container for
the performance rating.
1. Check the oil level before each use with a cool engine that is level.
2. Use 4-stroke motor oil that meets or exceeds the requirements for API
(American Petroleum Institute) service classification SF. Always check the API
Service label on the oil container to be sure it includes the letters SF.
3. Do not use special additives.
4. SAE 10W-30 is recommended for
general, all-temperature use. Other
viscosities shown on the chart may
be used when the average
temperature in your area is within
the indicated range (Fig. 4).
5. Above 27°C (80°F), using 10W-30
oil may increase oil consumption.
Check the oil level more often.
2-1
Fig. 3
Fig. 4
3-1

8449019 420cc OHV Gas Engine with Electric Start V 4.4
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6. Below 4°C (40°F), using SAE 30 oil will cause hard starting.
HOW TO CHECK OIL
1. Level the engine or the equipment the engine is mounted on.
2. Clean the oil fill area of any dirt and debris to prevent contamination that can
damage the engine.
3. The engine has a dipstick that is either part of the oil fill plug (O) or a separate
component (see Parts Identification).
a. Remove the dipstick (O) and wipe with a clean cloth.
b. Reinsert the dipstick into the filler neck until it rests on the opening’s rim.
Do not screw the oil fill plug back into the opening.
c. Remove the dipstick and check that the oil is between the Full and Fill
marks. Add or drain oil based on the measurement.
d. Reinsert the dipstick and either press firmly to hold in place or screw the
oil fill cap hand tight
HOW TO ADD OIL
IMPORTANT! Read the Engine Oil section before adding oil to ensure that it is
suitable for the engine.
1. Remove the oil filler cap (O) and place to one side.
2. Place a funnel into the oil fill neck. The funnel opening should be wide enough
to prevent the oil from collecting in the funnel’s cone.
Fig. 5
O

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3. Pour oil into the funnel. Allow the oil to settle for one minute and recheck the
level. Repeat until the desired level is reached.
4. Insert and hand tighten the oil filler cap.
5. Wipe up any spilled oil. Dispose of oil soaked rags in a proper hazardous
waste container.
HOW TO DRAIN OIL
WARNING! Draining oil from the engine may involve tipping it on the side. This
can cause fuel to leak into the oil compartment, creating a potential fire
hazard. Do not tip the engine while draining. If this is unavoidable, drain the
fuel from the engine before draining the oil.
1. Remove the dipstick (O).
2. Place an approved container below the
oil drain plug (Fig. 6).
3. Remove the oil drain plug and allow oil
to the drain into the approved container.
4. Install oil drain plug and tighten with
a wrench.
IMPORTANT! Used oil must be disposed of
properly. Do not pour it on the ground,
down a drain or throw it in the trash. Take the oil to your local recycling centre
or a service station for reclamation.
CARBURETOR ADJUSTMENT
Never make adjustments to the carburetor. The carburetor was set at the factory to
operate efficiently under most conditions. Only a qualified service technician should
adjust the carburetor if it is required.
MODIFYING THE CARBURETOR FOR HIGH ALTITUDES
At high altitude, the standard air-fuel mixture is too rich, causing increased fuel
consumption and decreased performance. A rich mixture will also foul the spark
plug and cause hard starting.
Fig. 6
O

8449019 420cc OHV Gas Engine with Electric Start V 4.4
18 For technical questions call 1-800-665-8685
A qualified technician can improve high altitude performance with certain
modifications. Have your carburetor modified if the engine will routinely be
operated at altitudes above 5,000 ft (1,500 m). Even with carburetor
modification, engine power will decrease about 3.5% for each 1,000 ft (305 m)
increase in altitude. The effect of altitude on power will be greater than this is if
no modification is made.
NOTICE! When the carburetor has been modified for high altitude operation, the
air fuel mixture will be too lean for low altitude use. Operation at altitudes
below 5,000 ft (1,500 m) may cause the engine to overheat and result in serious
engine damage. When using this engine at low altitudes, have a qualified
technician return the carburetor to original factory specifications.
CLEANING THE SEDIMENT CUP
CAUTION! Wear latex or rubber gloves when working on the sediment cup. The
cup may contain fuel that will cause skin irritation. Prolonged and repeated
exposure to fuel on skin may result in dry, cracked skin.
1. Switch the fuel valve to the OFF position.
2. Remove the fuel sediment cup, screw and o-ring.
3. Clean the sediment cup with a non-flammable solvent or detergent and rinse.
Allow to dry.
a. Some chemicals will damage the o-ring material. Check for compatibility
or simply replace the o-ring.
4. Reassemble the sediment cup and o-ring.
5. Switch the fuel valve to the ON position and check for leaks. Replace the
o-ring if the installation is correct, but fuel still leaks from the cup.
EMISSION CONTROL SYSTEM INFORMATION
The combustion process produces carbon monoxide, hydrocarbons and oxides of
nitrogen. Control of these emissions is very important for personal and
environmental health.
The following instructions must be followed in order to keep the emissions from
your engine within Canadian emission standards.

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1. Do not remove or alter any part of the intake, fuel, or exhaust systems.
2. Do not alter or bypass the governor linkage or speed-adjusting mechanism to
cause the engine to operate outside its design specifications.
PROBLEMS THAT MAY AFFECT EMISSIONS
If you are aware of any of the following symptoms, have your engine inspected and
repaired by a qualified technician.
1. Hard starting or stalling after starting.
2. Rough idle.
3. Misfiring or backfiring under load.
4. Afterburning (backfiring).
5. Black exhaust smoke or high fuel consumption.
REPLACEMENT PARTS
The emission control systems on your engine were designed, built and certified to
conform to Canadian emission regulations. The use of genuine parts is
recommended whenever maintenance is done to the engine. Genuine replacement
parts are manufactured to the same standards as the original parts. Using
replacement parts that are not of the original design and quality may impair the
effectiveness of your emission control system.
It is the responsibility of the manufacturer of an aftermarket part to certify
that use of the part will not result in a failure of the engine to comply with
emission regulations.
SERVICE THE AIR FILTER
NOTICE! Operating the engine with a damaged or missing air filter will allow
dust and debris to enter the engine, causing rapid engine wear or scoring on
the engine pistons. Always ensure the air filter is in place.
A dirty air filter will restrict airflow to the carburetor, reducing engine performance.
If the engine is used in very dusty areas, clean the air filter more frequently than
specified in the maintenance schedule.
1. Remove the air cleaner’s outside cover (Fig. 7). Be careful to prevent dirt and
debris from falling into the air cleaner assembly.

8449019 420cc OHV Gas Engine with Electric Start V 4.4
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2. Remove the air filter from the air filter housing.
3. Clean the housing interior with warm soap and water. Allow to dry
before reassembly.
4. Inspect the air filter to see if you can clean it or if it should be discarded.
Discard if it is too dirty and replace with a new filter.
a. Clean the dirty air filter by tapping it on a hard surface to dislodge dirt
and dust. Finer particulate matter
may still remain lodged in the
filter’s fibers.
b. Use clean compressed air to clean
the filter. Set the compressor to a
maximum of 30 PSI. Anything
higher can damage the filter. Hold
the air nozzle inside the filter and
direct the air stream outward to
blow the dirt and debris away from
the outer surface.
NOTICE! Do not use compressed air with chemicals to clean the air
filter. The chemicals could clog or dissolve the filter material.
c. Never attempt to brush the accumulated dust and debris from the filter.
This will only force the grime into the fibers and plug the filter.
5. Reinstall the filter into the housing and secure in place.
6. Install the air filter assembly onto the carburetor and secure with screw.
REPLACING THE SPARK PLUG
NOTICE! Using an incorrect spark plug can cause engine damage. Only replace
a spark plug with a model recommended by the manufacturer.
The spark plug must be properly gapped and free of deposits for the best
performance. Check local bylaws to see if a resistor spark plug is required to
suppress ignition signals. Replace the included spark plug with a resistor spark plug
if required.
Fig. 7