Power Fist 7-1/2 HP 212cc OHV User manual

V 4.0 8951907
Please read and understand all instructions before use. Retain this manual for future
reference.
User Manual
7-1/2 HP 212cc OHV
Gas Engine

8951907 7-1/2 HP 212cc OHV Gas Engine V 4.0
2 For technical questions call 1-800-665-8685
SPECIFICATIONS
Start Type
Pull
Torque
9.96 ft-lb
Shaft Diameter
3/4 in.
Shaft Length
2.43 in.
Shaft Rotation (From PTO Shaft Side)
Counterclockwise
Shaft End Tapped
(Diameter (in.) / Threads Per Inch)
5/16-24 UNF
Number of Cylinders
1
Cylinder Bore
2.76 in.
Stroke
2.17 in.
Compression Ratio
8.5:1
Cooling System
Air
Fuel Tank
Metal
Fuel Type
Gasoline
Fuel Tank Capacity
3.8 quarts (3.6 litres)
Fuel Filter
Yes
Oil Capacity
0.6 quarts (0.56 litres)
Lubrication System
Splash
Oil API Service Classification
SF or Newer
Low Oil Alert
No
Low Oil Shutdown
Yes
Governor System
Mechanical
Ignition System
Transistorized Magneto
Max. Speed
3,750 RPM
Muffler Included
Yes
Spark Plug (SKU #4780112)
Gap
0.028 ~ 0.031 in. (0.7 ~ 0.8 mm)
Torque
18 ~ 22 N-m
Air Cleaner Type
Foam
7-1/2 HP 212cc OHV
Gas Engine

V 4.0 7-1/2 HP 212cc OHV Gas Engine 8951907
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INTRODUCTION
The 7-1/2 HP 212cc OHV Gas Engine is ideal for commercial or agricultural
applications: pressure washers, tillers/cultivators, log splitters, go-karts, water
pumps, lawn and garden equipment, agricultural equipment and generators
The engine’s overhead valve design and electronic ignition make for easy
starting, increased power and better fuel economy. Meets all Environmental
Protection Agency (EPA) guidelines.
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.

8951907 7-1/2 HP 212cc OHV Gas Engine V 4.0
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. 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 the engine, as the engine can
snag the material and pull the hand into its moving parts.
3. Wear protective clothing designed for the work environment and engine.
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 any tool, personal movement and the work environment to avoid
personal injury or damage to the engine.
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 or the engine. Keep long hair covered or bound.

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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 engine (gained from
repeated use) replace strict adherence to 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 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 the 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 the muffler, engine cylinder and fins to cool before touching.
5. The manufacturer of the equipment on which this engine is installed specifies
the top speed at which the engine will operate. DO NOT exceed this speed.
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.

8951907 7-1/2 HP 212cc OHV Gas Engine V 4.0
6 For technical questions call 1-800-665-8685
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:
• Headache
• Confusion
• Shortness of breath
• Weakness
• Chest Pain
• Dizziness
• Blurred Vision
• Nausea and vomiting
• Unconsciousness
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
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.
Fig. 1

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A One Way Valve
B Muffler
C Spark Plug
D Dipstick
E Oil Drain Plug
F Fuel Valve
G Choke Lever
H Connecting Pipe
I Air Cleaner
J Throttle Lever
K Recoil Starter
Handle
L Recoil Starter
M Fuel Filler Cap
N Fuel Tank
O Engine Switch
P Dipstick
ASSEMBLY & INSTALLATION
Letter references in parenthesis (A) refer to the included Identification Key. Dashed
numbers in parenthesis (Fig. 1-1) refer to specific point of an illustration or image.
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. Replace oil cap for shipping with the vented/breather oil cap.
4. Check that the filter is in place. See Maintenance – Service the Air Filter
OPERATION
PRE-OPERATION CHECKS
NOTICE! The engine is not shipped with oil. Before starting the engine, add
oil according to the instructions in this manual. Starting the engine without
oil will damage the engine beyond repair.
Check the engine’s condition before operating to maximize the user’s safety and
the service life of the engine. Ensure that the engine is level and the switch is in
the OFF position before beginning the pre-operation checks.
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 (B), fuel cap (M) and air cleaner (I) 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.

8951907 7-1/2 HP 212cc OHV Gas Engine V 4.0
8 For technical questions call 1-800-665-8685
3. Check the air filter. A dirty air filter will reduce engine performance.
4. Check that all protective covers and guards are in place.
5. Check that all nuts, bolts and screws are tight.
6. Check the fuel level.
7. Check the engine oil level. Running the engine with a low level of oil can cause
engine damage (see How to Check/Add Oil).
8. 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.
9. Remove any excessive dirt or debris, especially around the muffler (B) and
recoil starter (L).
10. Look for signs of damage.
11. Check the equipment powered by this engine.
12. 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 (G) to the CLOSED position if the engine is cold. The
choke is unnecessary when restarting a warm engine.
3. Move the throttle lever (J) away from MIN. position, about 1/3 of way
toward the MAX. position.
4. Turn the engine switch (O) to the ON position.
5. Pull the starter handle (K) 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.

V 4.0 7-1/2 HP 212cc OHV Gas Engine 8951907
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6. If the engine floods, set the choke to the OPEN/RUN position, place the
throttle in FAST and attempt to start the engine again.
7. 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 to the OFF position to stop the engine.
Stop the engine by following this procedure:
1. Move the throttle lever (J) to the MIN. position.
2. Turn the engine switch (O) 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.
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.

8951907 7-1/2 HP 212cc OHV Gas Engine V 4.0
10 For technical questions call 1-800-665-8685
5. Disconnect the spark plug lead and keep it away from the spark plug
during maintenance and repairs.
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.
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 mo
nths
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.

V 4.0 7-1/2 HP 212cc OHV Gas Engine 8951907
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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.
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.

8951907 7-1/2 HP 212cc OHV Gas Engine V 4.0
12 For technical questions call 1-800-665-8685
3. Let engine cool at least 2 minutes before removing the fuel cap.
4. Clean the fuel cap (M) 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.
7. Add fuel until it reaches the bottom of the metal collar supporting the fuel
strainer in the fuel tank (Fig. 2-1). 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.
2-1
Fig. 2

V 4.0 7-1/2 HP 212cc OHV Gas Engine 8951907
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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. 3).
5. Above 27 °C (80 °F), using 10W-30
oil may increase oil consumption.
Check the oil level more often.
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 (E) or a
separate component (see Parts Identification).
a. Remove the dipstick (E) 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 (Fig. 4).
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.
Fig. 3
Fig. 4
E

8951907 7-1/2 HP 212cc OHV Gas Engine V 4.0
14 For technical questions call 1-800-665-8685
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 (E) 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.
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 the oil filler cap and hand tighten.
5. Wipe up any spilled oil. Dispose of oil soaked rags in a proper hazardous
waste container.
HOW TO DRAIN OIL
WARNING! Do not tip the engine while draining. This can cause fuel to leak
into the oil compartment, creating a potential fire hazard. If this is
unavoidable, drain the fuel from the engine before draining the oil.
1. Remove the dipstick (D).
2. Place an approved container below the oil drain plug (Fig. 5).
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.
Fig. 5

V 4.0 7-1/2 HP 212cc OHV Gas Engine 8951907
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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.
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 (1,524 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 engine 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 (1,524 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 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
nitrogen oxides. Controlling these emissions is important for personal and
environmental health.

8951907 7-1/2 HP 212cc OHV Gas Engine V 4.0
16 For technical questions call 1-800-665-8685
The following instructions must be followed in order to keep the emissions from
your engine within Canadian emission standards.
1. Do not remove or alter any part of the intake, fuel or exhaust system.
2. Do not alter or bypass the governor linkage or a speed-adjusting
mechanism that force the engine to operate outside its design
specifications.
PROBLEMS THAT MAY AFFECT EMISSIONS
Have your engine inspected and repaired by a qualified technician if you are
aware of any of the following symptoms.
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 the engine is designed, built and certified to
conform to Canadian emission regulations. Genuine parts are recommended when
servicing 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 the emission control system.
It is the responsibility of the aftermarket part manufacturer to certify that the part
will not void the engine’s compliance with emission standards and 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 the engine’s
performance. Clean the air filter more frequently than specified in the
maintenance schedule if the engine is used in dusty areas.
1. Remove the air cleaner’s outside cover (Fig. 6). Do not allow dirt and
debris from to fall into the air cleaner assembly.

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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. Remove the foam
precleaner that is wrapped
around the pleated paper
filter. Clean the dirty foam
air filter element with warm
water and mild soap.
Replace the water as
necessary, until the water is
no longer dirty. Allow to dry.
b. Tap the pleated filter against
a hard surface to dislodge dirt and dust. Finer particulate matter may
still remain lodged in the filter’s fibers.
c. Never attempt to brush the accumulated dust and debris from the
filter. This will force the grime into the fibers and plug the filter.
d. Reassemble the foam and paper filter elements.
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.
1. Remove any dirt from around the spark plug area.
Fig. 6

8951907 7-1/2 HP 212cc OHV Gas Engine V 4.0
18 For technical questions call 1-800-665-8685
2. Unclip the spark plug lead and remove the spark plug with a spark plug
wrench. This will have a rubber pad inside the socket to protect the spark
plug’s ceramic coating.
3. Inspect the spark plug. Replace it if damaged, badly fouled, the sealing
washer is in poor condition or the electrode is worn.
4. Check the gap with a spark plug
gauge as shown in Figure 7. If
necessary, reset the gap (See
Specifications).
a. Correct the gap by carefully
bending the electrode. Check
the gap after each
adjustment.
5. Install the spark plug carefully by
hand to avoid cross threading.
6. Tighten the spark plug to the
recommended torque until the
gasket is compressed. See
Specifications for the correct torque rating.
7. Reconnect the spark plug lead to the spark plug.
ADJUSTING THE ENGINE IDLE SETTING
NOTICE! The engine speed is set by the factory. Increasing the speed too much
can damage the engine. Too low a speed will reduce the engine’s efficiency.
Have a qualified technician adjust the engine speed if necessary.
The engine does not have a variable speed option. The engine’s idling speed is
adjustable by turning the governor arm screw to lower or increase the engine
output (RPMs).
1. Remove the shroud and locate the governor arm screw.
2. Start the engine and wait for it to idle.
3. Tighten the screw to increase the engine speed. Loosen to reduce speed.
4. Shut the engine off and allow to cool
5. Reattach the shroud.
Fig. 7

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CLEANING
WARNING! Only clean engine parts with a nonflammable solvent, unless
instructed otherwise. Keep all ignition sources away from fuel-related parts.
Fumes are flammable and may cause a burn injury or explosion if ignited.
NOTICE! Do not clean the engine’s exterior with a garden hose or pressure
washer. Water can enter the engine through the air filter or muffler opening
and damage the cylinder.
1. Allow engine to cool for at least half an hour before cleaning.
2. Clean all exterior surfaces.
3. Touch up any damaged paint.
4. Coat other areas that may rust with a light film of oil.
STORAGE
DANGER! Fuel is very flammable. Use extreme care when handling or storing
fuel. An ignition source contacting the fumes or fuel can result in a fire or
explosion and cause fatal or serious injuries to you or a bystander.
When not in use for an extended period, apply a thin coat of lubricant to the
steel parts to avoid rust. Remove the lubricant before using the engine again.
Proper storage preparation is essential for keeping your engine in good condition.
The steps below will help keep rust and corrosion from impairing your engine’s
function and appearance. The engine will easier to start when used again.
Take the following precautions if storing your engine for more than 30 days.
• Store in a clean dry area.
• Change the oil while the engine is still warm.
• Clean debris from the engine’s surface.
• Drain all fuel from the fuel tank into a proper receptacle for storage.
• Disconnect the spark plug lead and cover the end with insulating tape.
Place the lead where it cannot come in contact with the spark plug or the
equipment the engine is mounted on.
• Remove the spark plug. Place 1 teaspoon (5 ml) of oil into the spark plug hole.

8951907 7-1/2 HP 212cc OHV Gas Engine V 4.0
20 For technical questions call 1-800-665-8685
• Pull starter rope slowly 8 to 10 times to properly coat the cylinder bore and
piston for storage. Replace spark plug and tighten. Any residual oil will
burn off in subsequent starts. The muffler may emit white smoke.
• Store this engine in the horizontal position with the spark plug up. Do not
store or transport with the spark plug down. Storing or transporting with
the spark plug down will result in hard starting and/or engine smoking.
STORING ENGINE WITH FUEL
1. If your engine will be stored with gasoline in the fuel tank and carburetor, it
is important to reduce the hazard of gasoline vapour ignition.
a. Select a well-ventilated storage area away from any appliance that
operates with a flame, such as a furnace, water heater or clothes dryer.
b. Avoid any area with a spark-producing electric motor.
c. Avoid any area where power tools are operated.
2. If possible, avoid storage areas with high humidity, as this promotes rust
and corrosion.
3. Keep the engine level in storage. Tilting can cause fuel or oil leakage.
4. Cover the engine once the engine and exhaust system are cool. Some
materials can ignite or melt if the engine and/or exhaust system is hot. Do
not use sheet plastic as a dust cover.
a. Use a cover made from a breathable fabric to prevent rust and corrosion.
5. Store with gasoline that does not contain ethanol or a similar alcohol-
based fuel additive. Fuel with alcohol-based additives may phase separate
into gasoline, alcohol and water when stored for more than a few weeks.
FUEL
IMPORTANT! Avoid fuel phase separation by using premium quality fuel of at
least 89 octane.
Gasoline with ethanol or alcohol-based additives may phase separate and
deteriorate in storage. Phase separated gasoline will cause hard starting and
leave gum deposits that clog the fuel system. Phase separated fuel will contain
water that will prevent the engine from working and may damage the engine
systems. You may need to service or replace the carburetor and other fuel
system components if that gasoline in your engine deteriorates during storage.