Sym Quad Lander 250 User manual

Quad Lander 250
SERVICE MANUAL
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This service manual contains the technical data of each component inspection and
repair for the SANYANG Quad Lander 250 ATV. The manual is shown with
illustrations and focused on “Service Procedures”, “Operation Key Points”, and
“Inspection Adjustment” so that provides technician with service guidelines.
If the style and construction of the ATV, Quad Lander 250, are different from that
of the photos, pictures shown in this manual, the actual vehicle shall prevail.
Specifications are subject to change without notice.
Service Department
SANYANG INDUSTRY CO., LTD.
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HOW TO USE THIS MANUAL
This service manual describes basic information of different system parts and
system inspection & service for SANYANG Quad Lander 250 ATV. In addition,
please refer to the manual contents in detailed for the model you serviced in
inspection and adjustment.
The first chapter covers general information and trouble diagnosis.
The second chapter covers service maintenance information and special tools
manual.
The third to the 11th chapters cover engine and driving systems.
The 12th chapter is cooling system.
The 13th to the 16th chapter is contained the parts set of assembly frame body.
The 17th chapter is electrical equipment.
The 18th chapter is wiring diagram.
Please see index of content for quick having the special parts and system
information.
There are 4 buttons, “Forward”, “Contents”, “How to use this manual” and
“Mechanism Illustrations” on the CD-R version, and can be access to these items
by click the mouse.
If user wants to look for the content of each chapter, selecting the words of each
chapter on the contents can reach to each chapter. There are two buttons,
“Homepage and contents, onto the top line of first page of the each chapter. Thus,
if the user needs to check other chapters, he can click the top buttons to back the
homepage or contents. The content of each chapter can be selected too.
Therefore, when needs to checking the content inside of the chapter, click the
content words of the chapter so that can back to the initial section of the content.
In addition, there is a “To this chapter contents” button at the second page of each
contents so that clicking the button can back to the contents of this chapter.
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CONTENTS
Page Content Index
1-1 ~ 1-18 GENERAL INFORMATION
1
2-1 ~ 2-14 SERVICE MAINTENANCE INFORMATION
2
3-1 ~ 3-8 LUBRICATION SYSTEM 3
4-1 ~ 4-12 FUEL SYSTEM 4
5-1 ~ 5-6 ENGINE REMOVAL 5
6-1 ~ 6-16 CYLINDER HEAD/VALVE 6
7-1 ~ 7-8 CYLINDER/PISTON 7
8-1 ~ 8-14 “V” TYPE BELT DRIVING SYSTEM/KICK-STARTER 8
9-1 ~ 9-12 FINAL DRIVING MECHANISM 9
10-1 ~ 10-10 ALTERNATOR 10
11-1 ~ 11-8 CRANKSHAFT/ CRANKCASE 11
12-1 ~ 12-12 COOLING SYSTEM 12
13-1 ~ 13-14 BODY COVER 13
14-1 ~ 14-14 FRONT BRAKE AND FRONT WHEEL 14
15-1 ~ 15-10 STEERING/FRONT SUSPENSION 15
16-1 ~ 16-18 REAR BRAKE/REAR WHEEL/REAR CUSHION 16
17-1 ~ 17-22 ELECTRICAL EQUIPMENT 17
18-1 ~ 18-2 ELECTRICAL DIAGRAM
18
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SERIAL NUMBER
Frame number
Engine number
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1. GENERAL INFORMATION
1-1
Symbols and Marks............................. 1-1
General Safety..................................... 1-2
Service Precautions............................ 1-3
Specifications...................................... 1-9
Specifications..................................... 1-10
Torque Values.................................... 1-11
Troubles Diagnosis............................ 1-13
Lubrication Points ............................. 1-18
Symbols and Marks
Symbols and marks are used in this manual to indicate what and where the special service are needed, in
case supplemental information is procedures needed for these symbols and marks, explanations will be
added to the text instead of using the symbols or marks.
Warning Means that serious injury or even death may result if procedures are not
followed.
Caution Means that equipment damages may result if procedures are not followed.
Engine oil
Limits to use SAE 10W-30 API SG class oil. Warranty will not cover the
damage that caused by not apply with the limited engine oil.
(Recommended oil: KING MATE G-3 oil)
Grease King Mate G-3 is recommended.
Gear oil King Mate gear oil serials are recommended. (Bramax HYPOID GEAR OIL
# 140)
Locking sealant Apply sealant; medium strength sealant should be used unless otherwise
specified.
Oil seal Apply with lubricant.。
Renew Replace with a new part before installation.
Brake fluid Use recommended brake fluid DOT3 or WELLRUN brake fluid.
Special tools Special tools
Correct Meaning correct installation.
Wrong Meaning wrong installation.
Indication Indication of components.
Directions Indicates position and operation directions
Components assembly directions each other.
Indicates where the bolt installation direction, --- means that bolt cross
through the component (invisibility).
1
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1. GENERAL INFORMATION
1-2
General Safety
Carbon monoxide
If you must run your engine, ensure the place is
well ventilated. Never run your engine in a closed
area. Run your engine in an open area, if you
have to run your engine in a closed area, be sure
to use an extractor.
Caution
Exhaust contains toxic gas which may cause one
to lose consciousness and even result in death.
Gasoline
Gasoline is a low ignition point and explosive
material. Work in a well-ventilated place, no flame
or spark should be allowed in the work place or
where gasoline is being stored.
Caution
Gasoline is highly flammable, and may explode
under some conditions, keep it away from
children.
Used engine oil
Caution
Prolonged contact with used engine oil (or
transmission oil) may cause skin cancer although
it might not be verified.
We recommend that you wash your hands with
soap and water right after contacting. Keep the
used oil beyond reach of children.
Hot components
Caution
Components of the engine and exhaust system
can become extremely hot after engine running.
They remain very hot even after the engine has
been stopped for some time. When performing
service work on these parts, wear insulated
gloves and wait until cooling off.
Battery
Caution
• Battery emits explosive gases; flame is strictly
prohibited. Keeps the place well ventilated
when charging the battery.
• Battery contains sulfuric acid (electrolyte)
which can cause serious burns so be careful
do not be spray on your eyes or skin. If you
get battery acid on your skin, flush it off
immediately with water. If you get battery acid
in your eyes, flush it off immediately with
water and then go to hospital to see an
ophthalmologist.
• If you swallow it by mistake, drink a lot of
water or milk, and take some laxative such as
castor oil or vegetable oil and then go to see a
doctor.
• Keep electrolyte beyond reach of children.
Brake shoe
Do not use an air hose or a dry brush to clean
components of the brake system; use a vacuum
cleaner or the equivalent to avoid dust flying.
Caution
Inhaling brake shoe or pad ash may cause
disorders and cancer of the breathing system
Brake fluid
Caution
Spilling brake fluid on painted, plastic, or rubber
parts may cause damage to the parts. Place a
clean towel on the above-mentioned parts for
protection when servicing the brake system.
Keep the brake fluid beyond reach of children.
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1. GENERAL INFORMATION
1-3
Service Precautions
yAlways use with SANYANG genuine parts and
recommended oils. Using non-designed parts
for SANYANG ATV may damage the ATV.
ySpecial tools are designed for remove and
install of components without damaging the
parts being worked on. Using wrong tools may
result in parts damaged.
yWhen servicing this ATV, use only metric tools.
Metric bolts, nuts, and screws are not
interchangeable with the English system, using
wrong tools and fasteners may damage this
vehicle.
yClean the outside of the parts or the cover
before removing it from the ATV. Otherwise, dirt
and deposit accumulated on the part's surface
may fall into the engine, chassis, or brake
system to cause damage.
yWash and clean parts with high ignition point
solvent, and blow dry with compressed air. Pay
special attention to O-rings or oil seals because
most cleaning agents have an adverse effect on
them.
yNever bend or twist a control cable to prevent
unsmooth control and premature worn out.
yRubber parts may become deteriorated when
old, and prone to be damaged by solvent and oil.
Check these parts before installation to make
sure that they are in good condition, replace if
necessary.
yWhen loosening a component which has
different sized fasteners, operate with a
diagonal pattern and work from inside out.
Loosen the small fasteners first. If the bigger
ones are loosen first, small fasteners may
receive too much stress.
yStore complex components such as
transmission parts in the proper assemble order
and tie them together with a wire for ease of
installation later.
yNote the reassemble position of the important
components before disassembling them to
ensure they will be reassembled in correct
dimensions (depth, distance or position).
yComponents not to be reused should be
replaced when disassembled including gaskets
metal seal rings, O-rings, oil seals, snap rings,
and split pins.
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1. GENERAL INFORMATION
1-4
yThe length of bolts and screws for assemblies,
cover plates or boxes is different from one
another, be sure they are correctly installed. In
case of confusion, Insert the bolt into the hole to
compare its length with other bolts, if its length
out side the hole is the same with other bolts, it
is a correct bolt. Bolts for the same assembly
should have the same length.
yTighten assemblies with different dimension
fasteners as follows: Tighten all the fasteners
with fingers, then tighten the big ones with
special tool first diagonally from inside toward
outside, important components should be
tightened 2 to 3 times with appropriate
increments to avoid warp unless otherwise
indicated. Bolts and fasteners should be kept
clean and dry. Do not apply oil to the threads.
yWhen oil seal is installed, fill the groove with
grease, install the oil seal with the name of the
manufacturer facing outside, and check the
shaft on which the oil seal is to be installed for
smoothness and for burrs that may damage the
oil seal.
yRemove residues of the old gasket or sealant
before reinstallation, grind with a grindstone if
the contact surface has any damage.
yThe ends of rubber hoses (for fuel, vacuum, or
coolant) should be pushed as far as they can go
to their connections so that there is enough
room below the enlarged ends for tightening the
clamps.
yRubber and plastic boots should be properly
reinstalled to the original correct positions as
designed.
yThe tool should be pressed against two (inner
and outer) bearing races when removing a ball
bearing. Damage may result if the tool is
pressed against only one race (either inner race
or outer race). In this case, the bearing should
be replaced. To avoid damaging the bearing,
use equal force on both races.
Both of these examples can result in
bearing damage.
Manufacturer's name
Groove
Clamp
Connector
Boots
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1. GENERAL INFORMATION
1-5
yLubricate the rotation face with specified
lubricant on the lubrication points before
assembling.
yCheck if positions and operation for installed
parts is in correct and properly.
yMake sure service safety each other when
conducting by two persons.
yNote that do not let parts fall down.
yBefore battery removal operation, it has to
remove the battery negative (-) cable firstly.
Notre tools like open-end wrench do not contact
with body to prevent from circuit short and
create spark.
yAfter service completed, make sure all
connection points is secured.
Battery positive (+) cable should be connected
firstly.
yAnd the two posts of battery have to be greased
after connected the cables.
yMake sure that the battery post caps are
located in properly after the battery posts had
been serviced.
yIf fuse burned, it has to find out the cause and
solved it. And then replace with specified
capacity fuse.
Capacity
verification
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1. GENERAL INFORMATION
1-6
yWhen separating a connector, it locker has to
be unlocked firstly. Then, conduct the service
operation.
yDo not pull the wires as removing a connector
or wires. Hold the connector body.
yMake sure if the connector pins are bent,
extruded or loosen.
yInsert the connector completely.
If there are two lockers on two connector sides,
make sure the lockers are locked in properly.
Check if any wire loose.
yCheck if the connector is covered by the twin
connector boot completely and secured
properly.
yBefore terminal connection, check if the boot is
crack or the terminal is loose.
yInsert the terminal completely.
Check if the terminal is covered by the boot.
Do not let boot open facing up.
ySecure wires and wire harnesses to the frame
with respective wire bands at the designated
locations. Tighten the bands so that only the
insulated surfaces contact the wires or wire
harnesses.
yWire band and wire harness have to be
clamped secured properly.
yDo not squeeze wires against the weld or its
clamp.
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1. GENERAL INFORMATION
1-7
yDo not let the wire harness contact with rotating,
moving or vibrating components as routing the
harness.
yKeep wire harnesses far away from the hot
parts.
yRoute wire harnesses to avoid sharp edges or
corners and also avoid the projected ends of
bolts and screws.
yRoute harnesses so that they neither pull too
tight nor have excessive slack.
yProtect wires or wire harnesses with electrical
tape or tube if they contact a sharp edge or
corner. Thoroughly clean the surface where
tape is to be applied.
ySecure the rubber boot firmly as applying it on
wire harness.
yNever use wires or harnesses which insulation
has been broken. Wrap electrical tape around
the damaged parts or replace them.
yNever clamp or squeeze the wire harness as
installing other components.
Never Touch
Never too tight
Never clamp or
squeeze the wire
harness
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1. GENERAL INFORMATION
1-8
yDo not let the wire harness been twisted as
installation.
yWire harnesses routed along the handlebar
should not be pulled too tight or have excessive
slack, be rubbed against or interfere with
adjacent or surrounding parts in all steering
positions.
yBefore operating a test instrument, operator
should read the operation manual of the
instrument. And then, conduct test in
accordance with the instruction.
yWith sand paper to clean rust on connector
pins/terminals if found. And then conduct
connection operation later.
Do you know how to set the
instrument to its
measurement position and
the insert locations of its
two probes?
Clean rust
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1. GENERAL INFORMATION
1-9
Specifications
MAKER SANYANG MODEL UA25A
Overall Length 1890 mm Front Double arm
Overall Width 1055 mm Suspension
System Rear Unit Swing
Overall Height 1115 mm Front AT22x7-10 (off road)
Wheel Base 1200 mm Tire Specifications Rear AT22x10-9 (off road)
Front 810 mm Rim Aluminum
Dimension
Wheel tread Rear 805 mm Front Disk (ψ175mm)
Front 109 kg Brake System Rear Disk (ψ220mm)
Rear 114 kg Max. Speed Above 80 km/hr
Curb Weight Total 223 kg Performance Climb Ability Below 25°
Passengers/Weight Two /150 kg
Front 142 kg Primary
Reduction Belt
Rear 231 kg
Weight
Total Weight Total 373 kg Secondary
Reduction Gear / Sprocket
Type 4-Stroke Engine Clutch Centrifugal, dry type
Installation and
arrangement Vertical, below center, incline
Reduction
Transmission C.V.T., auto speed
change
Fuel Used Above 92 unleaded Speedometer 0 ~ 100 km/hr
Cycle/Cooling 4-stroke/water cooled Horn 93~112 dB/A
Bore Ø71 mm Muffler
Expansion & Pulse
Type
Stroke 63 mm Exhaust Pipe Position and
Direction Left side, and Backward
Cylinder
Number/Arrange
ment Single Cylinder Lubrication System Forced circulation & splashing
Displacement 249.4 cc Solid Particulate
Compression Ratio 10.5 : 1 CO Below 7.0 g/ km
Max. HP 13.2kw / 7000rpm HC Below 1.5g/ km
Max. Torque 20.6Nm / 5500rpm
Exhaust
Concentration
Nox Below 0.4g/ km
Ignition C.D.I. E.E.C. ─
Starting System Electrical starter P.C.V. ─
Engine
Air filtration Sponge Catalytic reaction control
system ─
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1. GENERAL INFORMATION
1-10
Specifications
MAKER SANYANG MODEL UA25A1
Overall Length 1890 mm Front Double arm
Overall Width 1055 mm Suspension
System Rear Unit Swing
Overall Height 1115 mm Front AT22x7-10 (on road)
Wheel Base 1200 mm Tire Specifications Rear AT22x10-9 (on road)
Front 810 mm Rim Aluminum
Dimension
Wheel tread Rear 805 mm Front Disk (ψ175mm)
Front 109 kg Brake System Rear Disk (ψ220mm)
Rear 114 kg Max. Speed Above 80 km/hr
Curb Weight Total 223 kg Performance Climb Ability Below 25°
Passengers/Weight Two /150 kg
Front 142 kg Primary
Reduction Belt
Rear 231 kg
Weight
Total Weight Total 373 kg Secondary
Reduction Gear / Sprocket
Type 4-Stroke Engine Clutch Centrifugal, dry type
Installation and
arrangement Vertical, below center, incline
Reduction
Transmission C.V.T., auto speed
change
Fuel Used Above 92 unleaded Speedometer 0 ~ 100 km/hr
Cycle/Cooling 4-stroke/water cooled Horn 93~112 dB/A
Bore Ø71 mm Muffler
Expansion & Pulse
Type
Stroke 63 mm Exhaust Pipe Position and
Direction Left side, and Backward
Cylinder
Number/Arrange
ment Single Cylinder Lubrication System Forced circulation & splashing
Displacement 249.4 cc Solid Particulate
Compression Ratio 10.5 : 1 CO Below 7.0 g/ km
Max. HP 13.2kw / 7000rpm HC Below 1.5g/ km
Max. Torque 20.6Nm / 5500rpm
Exhaust
Concentration
Nox Below 0.4g/ km
Ignition C.D.I. E.E.C. ─
Starting System Electrical starter P.C.V. ─
Engine
Air filtration Sponge Catalytic reaction control
system ─
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1. GENERAL INFORMATION
1-11
Torque Values
The torque values listed in above table are for more important tighten torque values. Please see standard
values for not listed in the table.
Standard Torque Values for Reference
Type Tighten Torque Type Tighten Torque
5 mm bolt、nut 0.45~0.6kgf-m 5 mm screw 0.35~0.5kgf-m
6 mm bolt、nut 0.8~1.2kgf-m 6 mm screw、SH nut 0.7~ 1.1kgf-m
8 mm bolt、nut 1.8~2.5kgf-m 6 mm bolt、nut 1.0 ~1.4kgf-m
10 mm bolt、nut 3.0~4.0kgf-m 8 mm bolt、nut 2.4 ~3.0kgf-m
12 mm bolt、nut 5.0~6.0kgf-m 10 mm bolt、nut 3.5~4.5kgf-m
Engine Torque Values
Item Q’ty Thread Dia. (mm) Torque Value(kgf-m) Remarks
Cylinder stud bolt 4 10 1.0~1.4
Cylinder head nut 4 8 3.6~4.0
Cylinder head right bolt 2 8 2.0~2.4
Cylinder head side cover bolt 2 6 1.0~1.4
Cylinder head cover bolt 4 6 1.0~1.4
Cylinder head stud bolt (inlet pipe) 2 6 1.0~1.4
Cylinder head stud bolt (EX. pipe) 2 8 2.4~3.0
Air inject pipe bolt 4 6 1.0~1.4
Air inject reed valve bolt 2 3 0.07~0.09
Tappet adjustment screw nut 4 5 0.7~1.1 Apply oil to thread
Spark plug 1 10 1.0~1.2
Tensioner lifter bolt 2 6 1.0~1.4
Carburetor insulator bolt 2 6 0.7~1.1
Oil pump screw 2 3 0.1~0.3
Water pump impeller 1 7 1.0~1.4
Engine left cover bolt 9 6 1.1~1.5
Engine oil draining bolt 1 12 3.5~4.5
Engine oil strainer cap 1 30 1.3~1.7
Mission draining bolt 1 8 1.1~1.5
Mission filling bolt 1 12 3.5~4.5
Shift drum fixing bolt 1 14 3.5~4.5
Clutch driving plate nut 1 28 5.0~6.0
Clutch outer nut 1 14 5.0~6.0
Drive face nut 1 14 8.5~10.5
ACG. Flywheel nut 1 14 5.0~6.0
Crankcase bolts 7 6 0.8~1.2
Mission case bolt 7 8 2.6~3.0
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1. GENERAL INFORMATION
1-12
Frame Torque Values
Item Q’ty Thread Dia. (mm) Torque Value(kgf-m) Remarks
Handlebar upper holder bolt 4 6 2.40
Steering shaft nut 1 10 5.00
Steering tie-rod nut 4 10 5.00
Knuckle nut 2 10 5.00
Steering shaft holder bolt 2 8 3.40
Tie rod lock nut 4 10 3.60
Handlebar under holder nut 2 8 4.00
Front wheel nut 8 10 2.40
Front axle castle nut 2 14 5.00
Rear axle castle nut 2 14 5.00
Rear wheel nut 8 10 2.40
Engine hanger nut 4 12 8.50
Rear axle holder bolt 4 12 9.20
Drive gear bolt 2 10 4.6
Driven gear nut 4 10 4.6
Swing arm pivot bolt 1 14 9.20
Front suspension arm nut 4 10 5.00
Front / Rear cushion mounting bolt 6 10 4.60
Brake lever nut 2 6 1.00
Brake hose bolt 13 10 3.50
Brake caliper bolt 6 6 3.25
Brake disk mounting bolt 11 8 4.25
Air-bleed valve 3 5 0.50
Exhaust muffler mounting bolt 2 8 3.00
Exhaust muffler connection nut 2 7 1.20
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1. GENERAL INFORMATION
1-13
Troubles Diagnosis
A. Engine hard to start or can not be started
Cylinder compression
pressure normal
Check and adjustment Fault condition Probable causes
Loosen carburetor drain bolt to
check if there is gasoline inside
the carburetor
Fuel supplied tom
carburetor sufficient No fuel is supplied to carburetor
Remove spark plug, install it
into spark plug cap, and perform
a spark test against engine
g
round.
Perform cylinder compression
pressure test.
Check if sparks Weak sparks, no spark at
all
Low compression
pressure or no pressure
Re-start by following the starting
procedures
No ignition There are some signs of
ignition; nut engine can
not
be started
Remove the spark plug again
and check it.
Remove carburetor after 30
minutes and connect a hose
onto fuel rich circuit. Then blow
the hose with air
Dry spark plug Wet spark plug
Blowing in normal Blowing clogged
yNo fuel in fuel tank
yCheck if the pipes, fuel tank to carburetor
and intake vacuum, are clogged.
yFloat valve clogged
yLines in fuel tank evaporation system
clogged
yMalfunction of fuel pump
yLoosen or damaged fuel pump vacuum
hose
yFuel filter clogged
yMalfunction of spark plug
ySpark plug foul
yMalfunction of CDI set
yMalfunction of AC generator
yIgnition coil is in open or short circuit
yIgnition coil leads open or short circuit
yMalfunction of main switch
yPiston ring seized
yMalfunction of cylinder valves
yWorn cylinder and piston ring
yCylinder gasket leak
ySand hole in compression parts
yMalfunction of throttle valve operation
yAir sucked into intake manifold
yIncorrect ignition timing
yFuel level in carburetor too high
yMalfunction of throttle valve operation
yThrottle valve opening too wide
yMalfunction of automatic by- starter
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1. GENERAL INFORMATION
1-14
B. Engine run sluggish (Speed does not pick up, lack of power)
Check and adjustment Fault condition Probable causes
Try gradual acceleration and
check engine speed
Engine speed can be
increased. Engine speed can not be increased.
Check ignition timing (Using
ignition lamp)
Check cylinder compression
pressure (using compression
pressure gau
ge)
Ignition timing correct Incorrect ignition timing
Compression pressure
correct No compression pressure
Check if carburetor jet is
clogged
No clogged Clogged
Remove spark plug
Check if engine over heat
No foul or discoloration Fouled and discoloration
No knock Knock
yAir cleaner clogged
yPoor fuel supply
yLines in fuel tank evaporation system
clogged
yExhaust pipe clogged
yFuel nozzle clogged in carburetor.
yFuel nozzle clogged in carburetor.
yMalfunction of CDI
yMalfunction of AC alternator
yCylinder & piston ring worn out
yCylinder gasket leaked
ySand hole in compression parts
yValve deterioration
ySeized piston ring
yRemove foreign
yRemove dirt
yIncorrect spark plug heat range
yPiston and cylinder worn out
yLean mixture
yPoor fuel quality
yToo much carbon deposited in
combustion chamber
yIgnition timing too advanced
yPoor circuit on the cooling system
Normal Engine overheat
Continually drive in acceleration
or high speed
yToo much carbon deposited in
combustion chamber
yLean mixture
yPoor fuel quality
yIgnition timing too advanced
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1. GENERAL INFORMATION
1-15
C. Engine runs sluggish (especially in low speed and idling)
D. Engine runs sluggish (High speed)
Check and adjustment Fault condition Probable causes
Check ignition timing (using
ignition lamp)
Check for fuel supplying system
in automatic fuel cup
Check if carburetor clogged
yIncorrect ignition timing (malfunction of
CDI or AC alternator)
yRich mixture (loosen the screw)
yLean mixture (tighten the screw)
yPoor heat insulation gasket
yCarburetor lock loose
yPoor intake gasket
yPoor carburetor O-ring
yVacuum hose crack
ySpark plug fouled
yMalfunction of CDI
yMalfunction of AC generator
yMalfunction of ignition coil
yOpen or short circuit in spark plug leads
yMalfunction of main switch
yInsufficient fuel in fuel tank
yFuel filter clogged
yRestricted fuel tank vent
Good Abnormal
Good spark Poor
No air sucked Air sucked
Good Poor
Normal Abnormal
Air sucked through carburetor
gasket
Adjust the air screw of
carburetor
Remove spark plug, install
spark plug into spark plug cap
and perform spark test against
engine ground
Check and adjustment Fault condition Probable causes
Check ignition timing
yMalfunction of CDI
yMalfunction of AC alternator
Normal Abnormal
No clogged Clogged yCleaning
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