YARDMAX 154FS-1 User manual

Save This Manual for Future Reference
Tame the Great OutdoorsTM
Gasoline Engine
Operator’s Manual
MODEL NUMBER
154FS-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

Introduction 1
Specications 3
Safety 3
Know Your Engine 4
Controls 5
Check before Operation 6
Operation 7
Maintenance 9
Storage 12
Technical & Consumer Information 13
Wiring Diagram 14
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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1
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Introduction

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.
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.
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:
All tools, hoses and packaging should be taken to the local
recycling center and disposed of in an environmentally
safe way.
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.
Coution!
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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Introduction
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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
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
The 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.
REFUEL WITH CARE
Gasoline is extremely ammable, and gasoline vapor can explode.
Refuel outdoors, in a well-ventilated area, with the engine stopped.
Never smoke near gasoline, and keep other ames and sparks away.
Always store gasoline in an approved container. If any fuel is spilled,
make sure the area is dry before starting the engine.
HOT EXHAUST
The mufer becomes very hot during operation and remains
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.
Model 154FS-1
Type 0.028" ~ 0.031"
Rated power
(kW/3600rpm)* 1.65Kw/3600rpm
Max torque N•m/rpm 4.5N.m/3800rpm
Fuel consumption ratio
(g/kW•h) ≤450
Speed uctuating ratio ≤10%
Noise ≤ dB(A) 70
Bore×Stroke (mm) 54×38
Displacement (cc) 87
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 no element
Dimension
(mm)
Length 344
Width 316
Height 327
Net weight (kg) 12.5
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Specications & Safty

To prevent re hazards and to provide adequate ventilation for
stationary equipment applications, keep the engine at least 3
feet (1 meter) away from building walls and 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.
Priming pump
Oil Dipstick
Choke Control
Air Box
Ignition Switch
Oil Drain Plug
Cylinder Head Cover
Spark Plug
Fuel Shutoff Valve
Starter Grip
Throttle Control
Fuel Tank
Fuel Filler Cap
Mufer
FEATURES AND CONTROLS
KNOW YOUR ENGINE
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Operator’s Manual
Know your Engine
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CONTROLS
The engine switch enables and
disables the ignition system.
The engine switch key must put in
for the engine to run.
Pulling out the engine switch key
will stop the engine.
The choke lever opens and closes
the choke valve in the carburetor.
Pulling the starter grip to crank the engine.
The CLOSE position enriches the fuel mixture for starting a cold
engine.
The OPEN position provides the correct fuel mixture for
operation after starting, and for restarting a warm engine.
Some engine applications use a remotely-mounted choke control
rather than the engine-mounted choke lever shown here. (See
Figure 2)
ENGINE SWITCH CHOKE LEVER
RECOIL STARTER GRIP
Figure 1a
Figure 1b
Figure 2
IN-ON
OUT-OFF
Engine Switch
OPEN
CLOSED
OPEN
CLOSED
Coution!
Don’t let the lever suddenly rebound, lightly put the
lever back.
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Controls

Figure 3
RECOIL START
Starter Grip
Figure 4
The Priming Pump supplies more
fuel to the carburetor when starting
the engine in the low temperature.
When you put the Priming Pump, you should not put more than
three times.
PRIMING PUMP
Notice:
Engines applied in snow blowers, are suggested
using between -22º F (-30º C) to 40º F (4.4º C). If
it operates below or above this temperature scope,
engines couldn't start or work normally.
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
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 the recommenced oil in the high
safe limits position.
4) After nishing, reassemble and screw the oil dipstick down.
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.
Coution!
Always check the engine oil on a level surface.
CHECK BEFORE OPERATION
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
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Controls & Check before Operation
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Figure 5
Figure 6
First stop the engine, open the fuel cap and check fuel level. If the
fuel level is too low, add fuel too full. When the fuel has been lled
too full, close the fuel tank by screwing the fuel cap back on.
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
Before operating the engine for the first time, please review
the IMPORTANT SAFETY INFORMATION and the chapter titled
BEFORE OPERATION.
2. To start a cold engine, move the
choke lever to the “CLOSED”
position. To start a warm
engine, turn the choke lever to
the “OPEN" position.
Review the instructions provided with the equipment powered
by this engine for any precautions and procedures that should be
followed before engine startup.
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 FUEL
SAFE OPERATING PRECAUTIONS
STARTING THE ENGINE
CHECK THE EQUIPMENT POWERED BY THIS ENGINE
Notice:
Running the engine with a low oil level can cause
engine damage, so always check the engine oil level
before startup.
Warning!
Carbon monoxide gas is toxic. Breathing it can cause
unconsciousness or death. Avoid any areas or actions
that expose you to carbon monoxide.
Oil Dipstick Lower Limit
Upper Limit
Fuel tank volume: 1.4 L
Maximum fuel oil level
Engine Switch
OPEN
CLOSED
1. Put the engine switch in the
key hole.
Figure 7a
OPERATION
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.
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Check before operation & Operation

Figure 7b
Figure 7e
OPEN
OPEN
CLOSED
CLOSED
Recoil Starter - Pull the starter grip lightly until you feel
resistance, then pull briskly. Return the starter grip gently.
Figure 7c
Starter Grip
Notice:
Starting the engine, carefully note the following:
When using the machine in very low temperatures, a
warm up period of up to 30 seconds may be required
of the engine prior to operation. If inconsistent engine
speeds are experienced when choke lever is rotated OPEN
position:
1. Move choke lever to mid-point between OPEN
and CLOSE positions and allow engine to develop
additional operating heat.
2. After engine has warmed up, move choke lever to
OPEN position.
3. 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.
OPEN
CLOSED
STOPPING THE ENGINE
To stop the engine in an emergency, simply turn the engine switch
to the “OFF” position. Under normal conditions, use the following
procedure. Pull out the engine switch.
Figure 8
The Engine Switch Key
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Operation
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THE IMPORTANCE OF MAINTENANCE
MAINTENANCE SCHEDULE
SAFETY PRECAUTIONS
Good maintenance is essential for safe, economical, and trouble-
free operation. It will also help reduce air pollution.
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.
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.
Mission-related items.
*These items should be serviced by your servicing dealer unless you have the proper tools and are mechanically procient.
MAINTENANCE
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.
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
Sediment Cup Clean
Spark plug Clean Replace
Valve clearance Check-Adjust *
Cover comp head Clean After every 150 Hrs.*
Fuel tank and fuel lter Clean Every 2 years (Replace if necessary)*
Fuel line Check Every 2 years (Replace if necessary)*
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Maintenance

REFUELING
FUEL RECOMMENDATIONS
CHECKING ENGINE OIL
ENGINE OIL CHANGE
With the engine stopped, remove the fuel tank cap and check the
fuel level. Rell the tank if the fuel level is low.
Use unleaded gasoline with a pump octane rating of 90 or higher,
You can also use other fuels, such as ethanol gasoline.
These engines are certied to operate on unleaded gasoline.
Unleaded gasoline produces fewer engine and spark plug deposits
and extends exhaust system life.
Never use stale or contaminated gasoline or an oil/gasoline
mixture. Avoid getting dirt or water in the fuel tank.
Occasionally you may hear a light ‘‘spark knock’’ or ‘‘pinging’’
(metallic rapping noise) while operating under heavy loads. This is
no cause for concern.
Check the engine oil level with the engine stopped and in a level position.
1. Remove the ller cap/dipstick and wipe it clean.
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 compatible with the environment.
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.
2. Insert and remove the dipstick without screwing it into the
ller neck. Check the oil level shown on the dipstick.
3. If the oil level is low, ll to the edge of the oil ller hole with the
recommended oil.
4. Screw in the ller cap/dipstick securely.
The Oil Alert system (applicable engine types) will automatically
stop the engine before the oil level falls below safe limit. However,
to avoid the inconvenience of an unexpected shutdown, always
check the engine oil level before startup.
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. Do not ll above the fuel strainer shoulder. After
refueling, tighten the fuel tank cap securely.
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 re hazard, it causes environmental
damage. Wipe up spills immediately.
Warning!
Gasoline is highly ammable and explosive. You can
be burned or seriously injured when handling fuel.
Stop the engine and keep heat, sparks, and ame
away.
Handle fuel only outdoors.
Wipe up spills immediately.
Figure 9
Fuel tank volume: 1.4 L
Maximum fuel oil level
Notice:
Fuel can damage paint and plastic. Be careful not to
spill fuel when lling your fuel tank. Damage caused
by spilled fuel is not covered under warranty.
Notice:
Running the engine with persistent spark knock or
pinging can cause engine damage.
Running the engine with persistent spark knock or pinging
is considered misuse, and the Distributor’s Limited
Warranty does not cover parts damaged by misuse.
Notice:
Running the engine with a low oil level can cause
engine damage.
If spark knock or pinging occurs at a steady engine speed, under
normal load, change brands of gasoline. If spark knock or pinging
persists, see an authorized servicing dealer.
Figure 10
Oil Dipstick Lower Limit
Upper Limit
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Maintenance
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ENGINE OIL RECOMMENDATIONS
SPARK PLUG
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.
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.
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 water.
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.
7. Assemble 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 12
Figure 11
3. With the engine in a level position, ll to the outer edge of the
oil ller hole with the recommended oil.
Engine oil capacities: 0.35 L
Running the engine with a low oil level can cause engine
damage.
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.
Oil Dipstick
Oil Upper Limit
Drain Bolt and
Sealing Washer
Spark Plug Wrench 0.028 ~ 0.031 in
(0.70 ~ 0.80 mm)
SAE Viscosity Grades
AMBIENT TEMPERATURE
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Maintenance

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 use sheet plastic as a dust cover. 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
cock.
3. Immediately reassemble sediment cup and drain bolt after fuel
completely draining. And screw down.
1) Change the engine oil.
2) Remove the spark plugs.
3) 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.
Spring
Bolt
4) Pull the starter rope several times to distribute the oil in
the cylinder.
5) Reinstall the spark plugs.
6) 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.
7) Put the out case on the engine and place in the ventilated
and dry area.
Figure 13
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Storage
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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
PARTS CATALOG
These publications will give you additional information for
maintaining and repairing your engine. You may order them from
your engine dealer.
This manual provides complete, illustrated parts lists.
13
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Technical & Consumer Information

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 DIAGRAM
B
G
BI
Spark
Plug
Engine
Switch
Transistorized
ignition unit
BI BLACK
B BLUE
Figure 14
14
Gasoline Engine
»
Operator’s Manual
Technical & Consumer Information & Wiring Diagram
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