YARDMAX LC152F-1 User manual

Save This Manual for Future Reference
Tame the Great OutdoorsTM
Gasoline Engine
Operator’s Manual
MODEL NUMBER
LC152F-1
SERIAL NUMBER
PURCHASE DATE
Both model number and serial
number may be found on the
main label. You should record
both of them in a safe place for
future use.
FOR YOUR SAFETY
READ AND UNDERSTAND THE ENTIRE MANUAL BEFORE OPERATING MACHINE
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Introduction 1
Specications 3
Safety 4
Know Your Engine 5
Controls 6
Check before Operation 7
Operation 8
Maintenance 9
Storage 13
Troubleshooting 14
Technical & Consumer Information 15
Wiring Diagram 16
TABLE OF CONTENTS
Your new YARDMAX™ engine offers quality construction
that is easy and safe to operate. With proper use and
care, it is designed to give you many years of dependable
service.
Prepare to experience the durability to take on any job
with the ease, portability, and convenience of your new
engine!
Discover the YARDMAX Advantage
At YARDMAX, we understand that land ownership
definitely has its privileges, but it also comes with a
great deal of responsibility. When duty calls and you
need to respond, will you have what it takes to tame the
great outdoors?
When looking for outdoor power equipment (OPE) to get
the job done right, at the right price, YARDMAX delivers
the perfect combination of performance and practicality.
YARDMAX has a solution that’s right for you.
MAX Performance, MAX Value, MAX Support —
that’s YARDMAX
Backed by decades of proven manufacturing expertise
Enhanced design features come standard
Engineered for the best user experience
Quality metal parts are used instead of plastic
A robust warranty supports all products
Budget-friendly prices make it practical
Up for the job? YARDMAX is.
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Introduction
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Carefully read through this entire operator’s manual
before using your new engine. Pay attention to all
cautions and warnings.
ENGINE SERIAL NUMBER
DISCLAIMER
YARDMAX reserves the right to discontinue, change,
and improve its products at any time without notice
or obligation to the purchaser. The descriptions and
specications contained in this manual were in effect at
printing. Equipment described within this manual may be
optional. Some illustrations may not be applicable to your
unit.
ENVIRONMENTAL
Recycle unwanted materials instead of disposing of
them as waste. All tools, hoses, and packaging should
be taken to the local recycling center and disposed of
in an environmentally safe way.
Record the engine serial number on the front cover of this
manual. You will need this serial number when ordering
parts, and when making technical or warranty inquires.
ENGINE TYPE
SERIAL NUMBER
DISCLAIMER
Keep this owner's manual handy, so you can refer to it at
any time.
This owner's manual is considered a permanent part of
the engine and should remain with the engine if resold.
The information and specifications included in this
publication were in effect at the time of approval for
printing.
READ THIS OWNER’S MANUAL CAREFULLY. Pay special
attention to these symbols and any instructions that follow:
Warning!
Indicates serious injury or death will result if
instructions are not followed.
Danger!
Indicates a strong possibility that serious injury or
death could result if instructions are not followed.
Caution!
Indicates a possibility that minor injury or an result if
instructions are not followed.
Notice:
Indicates that equipment or property damage can
result if instructions are not followed.
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* The power rating of the engine indicated in this document is the net power output tested on a production engine for the engine model
and measured in accordance with SAE J1349 at 3,600 rpm (Net Power) and at 3,800 rpm (Max. Net Torque). Mass production engines
may vary from this value.
* Actual power output for the engine installed in the nal machine will vary depending on numerous factors, including the operating speed
of the engine in application, environmental conditions, maintenance, and other variables.
SPECIFICATIONS
Model 152F-1
Type Single cylinder 4-Stroke
Forced air cooling
Rated power
(kW/3600rpm)* 1.5Kw/3600rpm
Max torque N•m/rpm 4N.m/3400rpm
Fuel consumption ratio
(g/kW•h) ≤450
Idle speed (rpm) 2000±150
Speed uctuating ratio ≤10%
Noise ≤ dB(A) 90
Bore×Stroke (mm) 52X37
Displacement (cc) 79
Compression ratio 8.5:1
Lubricating mode Splash
Staring mode Recoil start
Rotation Anti-clockwise
(from P.T.O.Side)
Valve clearance (mm) Intake valve 0.10-0.15
Exhaust valve 0.15-0.20
Spark plug gap (mm) 0.7~0.8
Ignition mode Transistorized magneto ignition
Air cleaner Single element
Dimension
(inch)
Length 12.2
Width 10.2
Height 12
Net weight (lbs) 23.1
SUPPORT
Have questions about your YARDMAX equipment?
Call us at 844-YARDMAX, email us at
[email protected], or contact us via your
favorite social media site.
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Specications
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SAFETY
IMPORTANT SAFETY INFORMATION
Most accidents with engines can be prevented if you follow all
instructions in this manual and on the engine. Some of the most
common hazards are discussed below, along with the best way to
protect yourself and others.
OWNER RESPONSIBILITIES
YARDMAX engines are designed to give safe and dependable
service if operated according to instructions. Read and
understand this owner’s manual before operating the engine.
Failure to do so could result in personal injury or equipment
damage.
Know how to stop the engine quickly, and understand the
operation of all controls. Never permit anyone to operate the
engine without proper instructions.
Do not allow children to operate the engine. Keep children and
pets far away from the area of operation.
OPERATOR SAFETY
Safety Measures
START/STOP SAFETY
Starting The Engine
Warning!
Wash hands after using the machine, refueling, and
changing uids. Certain components in this product
and its accessories contain chemicals known to cause
cancer, birth defects, or other reproductive harm
according to the State of California.
Warning!
Kick back or rapid retraction of the recoil cord will
pull the operators hand and arm towards the engine
quicker than you can let go.
Warning!
Always run your engine outdoors. Exhaust from the
engine contains fumes known to cause cancer, birth
defects, or other reproductive harm according to the
State of California.
Warning!
YARDMAX engines are not engineered or intended to
be used to power any other device than what it was
originally specified in. Including but not limited to
competitive racing events, recreational, sport or all-
terrain vehicles (ATV’s), go-karts, fun-karts, golf-carts, etc.
Avoiding Kick Back
Lightly pull the recoil handle so that the cord is taught prior to
pulling harder to start.
Grip the starter handle so you can quickly release it if needed.
If gripped too tightly injury could result.
When the rope is taut with resistance pull quickly and smoothly
to avoid kick back.
FUEL SAFETY
Warning!
Fuel and its vapors are extremely ammable and
explosive. Fire or explosion can cause severe burns or
death. Keep fuel away from sparks, open ames, pilot
lights, heat sources, or any other ignition sources. If
fuel spills, wait for it to completely evaporate before
starting the engine.
HOT EXHAUST
The mufer will become very hot during operation and will remain
hot for a while after stopping the engine. Be careful not to touch the
mufer while it is hot. Let the engine cool before storing it indoors.
To prevent re hazards and to provide adequate ventilation for
stationary equipment applications, keep the engine at least 3
feet (1 meter) away from both building walls and from other
equipment during operation. Do not place ammable objects
close to the engine.
CARBON MONOXIDE HAZARD
Exhaust gas contains poisonous carbon monoxide. Avoid
inhalation of exhaust gas. Never run the engine in a closed garage
or conned area.
OTHER EQUIPMENT
Review the instructions provided with the equipment powered
by this engine for any additional safety precautions that should
be observed in conjunction with engine startup, shutdown,
operation, or protective apparel that may be needed to operate
the equipment.
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Safety
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Oil Dipstick
Oil Sensor
Drain Plug
Switch
Oil Alert (Optional)
Choke Lever
Cylinder Head Cover
Spark Plug
Mufer
Air Cleaner
Recoil Starter
Starter Handle
Tank Cap
Fuel Tank
Throttle Control Assy
FEATURES AND CONTROLS
KNOW YOUR ENGINE
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Know your Engine
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CONTROLS
The engine switch enables and
disables the ignition system.
The engine switch must be in the
ON position for the engine to run.
Turning the engine switch to the
OFF position stops the engine.
The choke lever opens and closes
the choke valve in the carburetor.
Pulling the starter grip operates the recoil starter to crank the
engine.
Set lever “CLOSE” for starting a
cold engine.
After starting, set the choke lever
to “OPEN” position.
ENGINE SWITCH
CHOKE LEVER
RECOIL STARTER GRIP
Caution!
Don’t let the lever suddenly rebound, lightly put the
lever back.
Caution!
If the engine will not start or automatically stops
during operation, first check the engine oil and fuel
levels.
The engine switch
OFF
ON
Choke lever
Close
Open
Figure 1
RECOIL START
Starter Grip
Adjust the throttle lever position to
get required speed.
For proper engine speed, refer to
indication provided by equipment.
The oil protection system will stop engine operation if oil levels fall
below a safe operating level This will prevent engine damage from
occurring. To regain engine operation, ll the oil crankcase up to a safe
operating level indicated on the oil dipstick.
GOVERNOR LEVER
OIL PROTECTION SYSTEM (OPTIONAL)
Throttle lever
High Low
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Notice:
Your engine is shipped from YARDMAX without oil.
Add oil per the instructions before starting.
For your safety, and to maximize the service life of your
equipment, it is very important to take a few moments before you
operate the engine to check its condition. Be sure to take care
of any problem you nd, or have your servicing dealer correct it,
before you operate the engine.
Before beginning your preoperation checks, be sure the engine is
level and the engine key has been removed.
1. Check the General Condition of the Engine
Look around and underneath the engine for signs of oil or
gasoline leaks.
Remove any excessive dirt or debris, especially around the
mufer and recoil starter.
Look for signs of damage.
Check that all shields and covers are in place, and all nuts, bolts,
and screws are tightened.
2. Check Oil (See Figure 2)
1) Remove the oil dipstick and clean off with a towel.
2) Re-insert the oil dipstick and check the oil level without
screwing it down.
3) If the oil is too low, add enough oil to reach the high area of
the upper limit zone.
4) Reinstall and tighten oil dipstick back on the engine.
CHECK BEFORE OPERATION
IS YOUR ENGINE READY TO GO?
Warning!
Improperly maintaining this engine, or failing to
correct a problem before operation, could cause a
malfunction in which you could be seriously injured.
Warning!
Always perform a preoperation inspection before
each operation, and correct any problem.
Caution!
Always check the engine oil on a level surface.
CHECK BEFORE OPERATION
Figure 3
3. Check before Operation
Check that the spark plug, mufer, fuel cap, and air cleaner (if
equipped) are clean and secured in place.
If the spark plug is unplugged or removed do not crank the
engine.
CHECK FUEL (See Figure 3)
Turn engine off, open the fuel cap and check the fuel level. If the
fuel level is to low, add fuel until full. When the unit has been
filled completely, replace the fuel cap and tighten the fuel cap
clockwise.
Refuel in a well-ventilated area before starting the engine. If the
engine has been running, allow it to cool. Refuel carefully to avoid
spilling fuel. Don’t add the fuel over the shoulder of the Fuel Tank
(maximum fuel level).
Never refuel the engine inside a building where gasoline fumes
may reach ames or sparks. Keep gasoline away from appliance
pilot lights, barbecues, electric appliances, power tools, etc.
Spilled fuel is not only a fire hazard, it causes environmental
damage. Wipe up spills immediately.
Notice:
Running the engine with a low oil level can cause
engine damage, so always check the engine oil level
before startup.
Figure 2
Oil Dipstick Lower Limit
Upper Limit
Fuel tank volume: 1.6 L
Maximum fuel oil level
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Check before Operation
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Figure 4
Figure 5
Review the instructions provided with the equipment powered
by this engine for any precautions and procedures that should be
followed before engine startup.
Remove the air cleaner housing and check the element, if the
element is dirty, remove and clean. If the element is damaged,
replace entire element.
To start a cold engine, move
the choke lever to the CLOSE
position.
To start a warm engine, turn
the choke lever to the OPEN
position.
Pull the starter grip lightly until you feel resistance, then pull
briskly. (See Figure 5)
If the choke lever has been
moved to the CLOSE position
to start the engine, gradually
move it to the OPEN position
as the engine warms up.
Only use unleaded gasoline with an octane rating over 90. This
will help eliminate carbon deposits and extended the service life
of the engine. Do not use gasoline mixed with oil or contaminated
with dirt or water.
CHECK THE EQUIPMENT POWERED BY THIS ENGINE
CHECK AIR CLEANER (See Figure 4)
STARTING ENGINE
Nut M6
Air Cleaner Elbow
Support Plate
Element
Cover Screw
OPERATION
Choke lever
Close
Open
Turn the engine switch to the
ON position.
Move the throttle lever away from the LOW position, about 1/3
of the way toward the HIGH position.
The engine switch
ON
Governor lever
1.
4.
5.
2.
3.
Starter Grip
Caution!
Don’t let starting lever suddenly rebound, and lightly
put the lever back.
Choke lever
Open
To stop the engine in an emergency, simply turn the engine switch
to the OFF position. Under normal conditions, use the following
procedure.
STOPPING THE ENGINE
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Move the throttle lever to the
LOW position
Turn the engine switch to the
OFF position.
2.1.
Throttle lever
High Low
The engine switch
OFF
MAINTENANCE
MAINTENANCE SCHEDULE
(1) Service more frequently when used in dusty areas.
(2) These items should be serviced by your servicing dealer unless you have the proper tools and are mechanically procient.
REGULAR SERVICE PERIOD Each use First month
or 20 Hrs.
Every 3
months or
50 Hrs.
Every 6
months or
100 Hrs.
Every year
or
150 Hrs.
Engine oil
Check level
Change
Air cleaner
Check
Clean (1)
Replace (2)
Sediment Cup Clean
Spark plug Clean Replace
Valve clearance Check-Adjust (2)
Cover comp head Clean After every 300 Hrs. (2)
Fuel tank and fuel lter Clean Every 2 years (Replace if necessary) (2)
Fuel line Check Every 2 years (Replace if necessary) (2)
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Operation & Maintenance
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THE IMPORTANCE OF MAINTENANCE
SAFETY PRECAUTIONS
We recommend you take your YARDMAX engine to a YARDMAX
authorized service center to have all maintenance and service of
the engine and its parts.
Unintentional start up can create entanglement, laceration, or
amputation.
Before performing maintenance or service on your YARDMAX
engine take the following steps to ensure a safe work
environment
To help you properly care for your engine, the following pages
include a maintenance schedule, routine inspection procedures,
and simple maintenance procedures using basic hand tools. Other
service tasks that are more difcult, or require special tools, are
best handled by professionals and are normally performed by a
technician or other qualied mechanic.
The maintenance schedule applies to normal operating conditions.
If you operate your engine under unusual conditions, such as
sustained high-load or high-temperature operation, or use in
unusually wet or dusty conditions, consult your servicing dealer
for recommendations applicable to your individual needs and use.
Warning!
Improperly maintaining this engine, or failure to
correct a problem before operation, can cause a
malfunction in which you can be seriously hurt or
killed. Always follow the inspection and maintenance
recommendations and schedules in this owner’s
manual.
Warning!
The fuel tank must be emptied, if mounted on the
engine, prior to performing maintenance. Tipping of
the engine may cause the fuel to leak out causing a
re or explosion.
Warning!
Always unplug the spark plug before performing
service. Spark can result in re or electric shock.
Make sure all drive controls are disengaged.
Move the stop switch to off or remove the ignition key if
equipped.
Unplug the spark plug wire.
If the engine is installed on the machine block the wheels to
prevent movement or tipping.
To ensure safe operation after maintenance is performed
follow these guidelines:
Use only the correct tools.
Do not tamper with the governor spring, links, or other parts
to increase speed.
Only use YARDMAX approved replacement parts.
Do not strike the ywheel with a hammer or other hard
object.
When testing for spark:
Use an approved spark plug tester.
Never check for spark with the plug removed.
Make sure the engine is off before you begin any maintenance
or repairs. This will eliminate several potential hazards:
Carbon monoxide poisoning from engine exhaust.
Be sure there is adequate ventilation whenever you operate
the engine.
Burns from hot parts.
Let the engine and exhaust system cool before touching.
Injury from moving parts.
Do not run the engine unless instructed to do so.
Read the instructions before you begin, and make sure you
have the tools and skills required.
To reduce the possibility of re or explosion, be careful when
working around gasoline. Use only a nonammable solvent,
not gasoline, to clean parts. Keep cigarettes, sparks and ames
away from all fuel-related parts.
Remember that your servicing dealer knows your engine best and
is fully equipped to maintain and repair it.
To ensure the best quality and reliability, use only new, genuine
parts or their equivalents for repair and replacement.
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ENGINE OIL CHANGE
Drain the used oil while the engine is warm. Warm oil drains
quickly and completely.
1. Place a suitable container below the engine to catch the used
oil, and then remove the ller cap and the drain plug.
2. Allow the used oil to drain completely, and then reinstall the
drain plug, and tighten it securely. Please dispose of used
motor oil in a manner that is environmentally friendly. We
suggest you take used oil in a sealed container to your local
recycling center or service station for reclamation. Do not
throw it in the trash; pour it on the ground; or down a drain.
Notice:
Operating the engine without element or with a
damaged element will allow dirt to enter the engine,
causing rapid engine wear.
ENGINE OIL RECOMMENDATIONS
MAINTAINING AIR CLEANER
Using the proper type and weight of oil in the engine is extremely
important, as is daily checking of oil level oil, or using dirty oil, will
cause premature engine wear and failure.
Oil Type - When the ambient temperature is under -25°C, SAE
0W-30/40 is recommended for general use; when the ambient
temperature is above -25°C but under 4.4°C, SAE 5W-30 or 0W-
30/40 is recommended for general use. The SA oil viscosity and
service classication are in the API label on the oil container. We
recommend that you use API SERVICE Category SF or higher class oil.
A dirty air lter will restrict air ow to the carburetor, reducing
engine performance.
If you operate the engine in very dusty areas, clean the air lter
more often than specied in the MAINTENANCE SCHEDULE.
Figure 6
Figure 7
Figure 8
3. With the engine in a level position, ll to the outer edge of the
oil ller hole with the recommended oil.
1. Screw off air cleaner bolt and remove the cover.
2. Remove foam element.
Check element and renew if damaged Wash foam element:
Wash the cover and lter in warm, soapy water, rinse, and
allow drying thoroughly. Or clean in nonammable solvent and
allow drying. Dip in clean engine oil, and then squeeze out all
excess oil.
Empty the used oil from the air cleaner case, wash out any
accumulated dirt with nonammable solvent, and dry the case.
Engine oil capacities: 0.37 Quarts
Running the engine with a low oil level can cause engine
damage.
If the engine is equipped the Oil Alert system. The Oil Alert system
(applicable engine types) will automatically stop the engine before
the oil level falls below the safe limit.
However, to avoid the inconvenience of an unexpected
shutdown, ll to the upper limit, and check the oil level
regularly.
4. Screw in the ller cap/dipstick securely.
SAE Viscosity Grades
AMBIENT TEMPERATURE
Oil Dipstick
Oil Upper Limit
Drain Bolt and
Sealing Washer
Nut M6
Air Cleaner Elbow
Support Plate
Element
Cover Locking Nuts
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Maintenance
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WASHING SEDIMENT CUP
SPARK PLUG
(First check fuel tank for fuel, if having, drain the fuel in the fuel
tank completely.)
3. Inspect the spark plug. Replace it if the electrodes are worn, or
if the insulator is cracked or chipped.
4. Measure the spark plug electrode gap with a suitable gauge.
The gap should be 0.028 - 0.031 in (0.70 - 0.80 mm). Correct
the gap, if necessary.
5. Install the spark plug carefully, by hand, to avoid cross-
threading.
6. After the spark plug seats, tighten with a spark plug wrench to
compress the seal.
If reinstalling the used spark plug, tighten 1/8 - 1/4 turn after
the spark plug seats.
If installing a new spark plug, tighten 1/2 turn after the spark
plug seats.
1. Disconnect the spark plug cap, and remove any dirt from
around the spark plug area.
2. Remove the spark plug with a spark plug wrench.
7. Plug the spark plug wire onto the top of the spark plug.
Recommended spark plugs: E7RTC or other equivalents.
Notice:
An incorrect spark plug can cause engine damage.
Notice:
A loose spark plug can overheat and damage the
engine. Over tightening the spark plug can damage
the threads in the cylinder head.
Figure 10
Figure 11
Figure 9
3. Clean the air cleaner, cover and rubber gasket, preventing dust
entering into carburetor.
4. Reassemble the foam element, paying attention to rubber
gasket underneath the element.
5. Reassemble the air cleaner, and tighten the wing nut securely.
1. Remove the fuel sediment cup and O-ring.
2. Wash the sediment cup and O-ring in nonammable solvent,
and dry them thoroughly.
3. Place the O-ring in the fuel valve, and install the sediment cup.
Tighten the sediment cup securely.
4. Move the fuel valve to the ON position, and check for leaks.
Replace the O-ring if there is any leakage.
Spark Plug Wrench 0.028 ~ 0.031 in
(0.70 ~ 0.80 mm)
O-ring
Sediment cup
ADJUSTING IDLE SPEED
1. Start the engine outdoors, and allow it to warm up to operating
temperature.
2. Move the throttle lever to its slowest position.
3. Turn the idle speed screw to obtain the standard idle speed.
Standard idle speed: 2000±150 rpm.
Screw
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STORAGE
STORAGE PREPARATION
CLEANING
REMOVAL FROM STORAGE
TRANSPORTING
DRAINING CARBURETOR
Proper storage preparation is essential for keeping your engine
trouble free and looking good. The following steps will help to
keep rust and corrosion from impairing your engine’s function and
appearance, and will make the engine easier to start after storage.
If the engine has been running, allow it to cool for at least half an
hour before cleaning. Clean all exterior surfaces, touch up any
damaged paint, and coat other areas that may rust with a light lm
of oil.
Check your engine as described in the chapter CHECK BEFORE
OPERATION.
If the fuel was drained during storage preparation, ll the tank with
fresh gasoline. If you keep a container of gasoline for refueling, be
sure that it contains only fresh gasoline. Gasoline oxidizes and
deteriorates over time, causing hard starting.
If the cylinders were coated with oil during storage preparation,
the engine may smoke briey at startup. This is normal.
If the engine has been running, allow it to cool for at least 15
minutes before loading the engine-powered equipment on the
transport vehicle. A hot engine and exhaust system can burn you
and can ignite some materials.
Keep the engine level when transporting to reduce the possibility
of fuel leakage.
If your engine will be stored with gasoline in the fuel tank and
carburetor, it is important to reduce the hazard of gasoline
vapor ignition. Select a well-ventilated storage area away from
any appliance that operates with a ame, such as a furnace,
water heater, or clothes dryer. Also avoid any area with a spark-
producing electric motor, or where power tools are operated.
If possible, avoid storage areas with high humidity, because that
promotes rust and corrosion.
Be sure all fuel has been drained from the fuel tank, to reduce the
possibility of fuel leakage.
Position the equipment so the engine is level. Tilting can cause fuel
or oil leakage.
With the engine and exhaust system cool, cover the engine to
keep out dust. A hot engine and exhaust system can ignite or melt
some materials. Do not cover the with a plastic sheet or tarp. A
nonporous cover will trap moisture around the engine, promoting
rust and corrosion.
If equipped with a battery for an electric starter, recharge the
battery once a month while the engine is in storage. This will help
to extend the service life of the battery.
1. Place a container underneath the carburetor, and use funnel
to avoid spattering.
2. Remove the drain plug and sediment cup, then, open the fuel valve.
3. Immediately reassemble sediment cup and drain bolt after fuel
has completely drained.
4. Change the engine oil.
5. Remove the spark plug.
6. Pour a tablespoon (5-10 cc) of clean engine oil into the cylinder.
Notice:
Using a garden hose or pressure washing equipment
can force water into the air cleaner or muffler
opening. Water in the air cleaner will soak the air
lter, and water that passes through the air lter or
mufer can enter the cylinder, causing damage.
Notice:
Water contacting a hot engine can cause damage. If
the engine has been running, allow it to cool for at
least half an hour before washing.
7. Pull the starter rope several times to distribute the oil in the
cylinder.
8. Reinstall the spark plugs.
9. Pull the starter rope slowly until resistance is felt. This will
close the valves so moisture cannot enter the engine cylinder.
Return the starter rope gently.
10. Plug the spark plug wire to the spark plug.
Figure 12
Spring
Bolt
O-ring
Sediment cup
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Storage
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TROUBLESHOOTING
ENGINE WILL NOT START Possible Cause Correction
1.Electric starting: check
battery Battery discharged Recharge battery
2. Check control positions
Fuel valve OFF
Choke OPEN
Engine switch OFF
Move lever to ON
Move lever to CLOSE unless engine
is warm.
Turn engine switch to ON
3. Check fuel
Out of fuel
Bad fuel; engine stored without
treating or draining gasoline, or
refueled with bad gasoline
Refuel
Drain fuel tank and carburetor
Refuel with fresh gasoline
4. Remove and inspect
spark plugs
Spark plugs faulty, fouled, or
improperly gapped
Spark plugs wet with fuel
(ooded engine)
Gap, or replace spark plugs
Dry and reinstall spark plugs
Start engine with throttle
lever in FAST position
5. Take engine to an
authorized servicing
dealer, or refer to
manual
Fuel lter clogged, carburetor
malfunction, ignition malfunction,
valve stuck, etc
Replace or repair faulty
components as necessary
ENGINE LACKS POWER Possible Cause Correction
1. Check air lter Filter element(s) clogged Clean or replace lter element(s)
2. Check fuel
Out of fuel
Bad fuel; engine stored without treating
or draining gasoline, or refueled with
bad gasoline
Refuel
Drain fuel tank and carburetor
Refuel with fresh gasoline
3. Take engine to an
authorized servicing
dealer, or refer to
manual
Fuel lter clogged, carburetor
malfunction, ignition malfunction,
valve stuck, etc
Replace or repair faulty
components as necessary
14
Gasoline Engine
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Operator’s Manual
Troubleshooting
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15
TECHNICAL & CONSUMER INFORMATION
CARBURETOR MODIFICATION FOR HIGH ALTITUDE OPERATION
SOURCE OF EMISSIONS
PROBLEMS THAT MAY AFFECT EMISSIONS
REPLACEMENT PARTS
TAMPERING AND ALTERING
At high altitude, the standard carburetor air-fuel mixture will be
too rich. Performance will decrease, and fuel consumption will
increase. A very rich mixture will also foul the spark plug and
cause hard starting. Operation at an altitude that differs from that
at which this engine was certied, for extended periods of time,
may increase emissions.
High altitude performance can be improved by specic
modications to the carburetor. If you always operate your engine
at altitudes above 5,000 feet (1,500 meters), have your servicing
dealer perform this carburetor modication. This engine, when
operated at high altitude with the carburetor modications for
high altitude use, will meet each emission standard throughout its
useful life.
Even with carburetor modication, engine horsepower will
decrease about 3.5% for each 1,000-foot (300-meter) increase in
altitude. The effect of altitude on horsepower will be greater than
this if no carburetor modication is made.
The combustion process produces carbon monoxide, oxides of
nitrogen, and hydrocarbons. Control of hydrocarbons and oxides
of nitrogen is very important because, under certain conditions,
they react to form photochemical smog when subjected to
sunlight. Carbon monoxide does not react in the same way, but it
is toxic.
This utilizes lean carburetor settings and other systems to
reduce the emissions of carbon monoxide, oxides of nitrogen and
hydrocarbons.
If you are aware of any of the following symptoms, have your
engine inspected and repaired by your servicing dealer.
Hard starting or stalling after starting.
Rough idle.
Misring or backring under load.
Afterburning (backring).
Black exhaust smoke or high fuel consumption.
We recommend the use of genuine parts whenever you have
maintenance done. These original-design replacement parts are
manufactured to the same standards as the original parts, so you
can be condent of their performance. The use of replacement
parts that are not of the original design and quality may impair the
effectiveness of your emission control system.
A manufacturer of an aftermarket part assumes the responsibility
that the part will not adversely affect emission performance. The
manufacturer or rebuilder of the part must certify that use of
the part will not result in a failure of the engine to comply with
emission regulations.
Tampering with or altering the emission control system may
increase emissions beyond the legal limit. Among those acts that
constitute tampering are:
Removal or alteration of any part of the intake, fuel or exhaust
systems.
Altering or defeating the governor linkage or speed-adjusting
mechanism to cause the engine to operate outside its design
parameters.
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 feet (1,500meters) with a modified
carburetor may cause the engine to overheat and
result in serious engine damage. For use at low
altitudes, have your servicing dealer return the
carburetor to original factory specications. MAINTENANCE
Follow the maintenance schedule. Remember that this schedule
is based on the assumption that your machine will be used for
its designed purpose. Sustained high-load or high-temperature
operation, or use in unusually wet or dusty conditions, will require
more frequent service.
ENGINE TUNE-UP
ITEM SPECIFICATION
Spark plug gap 0.028-0.031 in
(0.70 mm -0.80 mm)
Valve clearance IN: 0.10 mm ~ 0.15 mm (cold)
EX: 0.15 mm ~ 0.20 mm (cold)
Other specications No other adjustments needed
PUBLICATIONS
These publications will give you additional information for
maintaining and repairing your engine. You may order them from
your engine dealer.
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Technical & Consumer Information
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16
Gasoline Engine
»
Operator’s Manual
Non-electric starting engine with oil protection system.
Engine Oil
Spark plug gap
Type SAE 5W-30, API SE or SF, for general use. Refer to engine oil recommendation.
Capacity 0.35 L
Valve clearance
Other specications
Type E7RTC or other equivalents.
Gap 0.028 ~ 0.031 in (0.70 ~ 0.80 mm)
Maintenance
Each use Check engine oil.
First 20 hours Change engine oil.
Subsequent Refer to the maintenance
QUICK REFERENCE INFORMATION
WIRING DIAGRAMS
IG E ST BAT
OFF
ON
START
Y
Y
Y
BI
BI
Spark
Plug
Engine
Switch
Oil alert unit
Oil sensor
Transistorized
ignition unit
BI BLACK
YYELLOW
G GREEN
Figure 13
Technical & Consumer Information & Wiring Diagram
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17
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18
Gasoline Engine
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Operator’s Manual
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Tame the Great OutdoorsTM
1850 W Winchester Rd, Suite 106 | Libertyville, IL 60048 | 844-YARDMAX (844-927-3629) | [email protected]
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