Sym RV 250i User manual

GTS 250i/ RV 250i
GTS 300i/ JOYMAX 300i
SERVICE MANUAL
FOREWORD
HOW TO USE THIS MANUAL
CONTENTS
SERIAL NUMBER

Foreword
This service manual contains the technical data of each component inspection and
repair for the SANYANG LM25W5 / LM30W series scooter. The manual is shown
with illustrations and focused on “Service Procedures”, “Operation Key Points”,
and “Inspection Adjustment”, providing technicians with service guidelines.
If the style or the mechanical structures of the scooter, LM25W5 / LM30W series
scooter are different from those of the photos or pictures shown in this manual, the
actual vehicle shall prevail. Specifications are subject to changes without notice.
Service Department
SANYANG INDUSTRY CO., LTD.
Homepage Contents

How To Use This Manual
This service manual describes the basic information of different system parts and
system inspection & service for SANYANG LM25W5 / LM30W series scooter. In
addition, please refer to the manual contents in detail for the model you serviced in
inspection and adjustment.
The first chapter covers the general information and the trouble diagnosis.
The second chapter covers the periodic maintenance information and the special
tool models.
The third to the 11th chapters cover the engine and the driving systems.
The 12th chapter is the cooling system.
The 13th to the 16th chapter contain the relative parts of the body frame assembly.
The 17th chapter is the electrical system.
The 18th chapter is the emission control system.
The 19th chapter is the wiring diagram.
Please see index of content for quick having the special parts and system
information.
There are 4 buttons, “Foreword”, “Contents”, “How to use this manual” and
“Mechanism Illustrations” on the PDF 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.
Homepage Contents

Contents
Page Content Index
1-1 ~ 1-18 General Information
1
2-1 ~ 2-18 Maintenance Information
2
3-1 ~ 3-8 Lubrication System 3
4-1 ~ 4-60 Fuel Injection System 4
5-1 ~ 5-12 Engine Removal 5
6-1 ~ 6-16 Cylinder Head / Valve 6
7-1 ~ 7-8 Cylinder / Piston 7
8-1 ~ 8-14 V-Belt Drive System 8
9-1 ~ 9-8 Final Drive Mechanism 9
10-1 ~ 10-10 AC Generator / Start Clutch 10
11-1 ~ 11-8 Crankshaft / Crankcase 11
12-1 ~ 12-14 Cooling System 12
13-1 ~ 13-14 Body Cover 13
14-1 ~ 14-12 Brake System 14
15-1 ~ 15-10 Steering / Front Wheel / Front Cushion 15
16-1 ~ 16-6 Rear Wheel / Rear Fork / Rear Cushion 16
17-1 ~ 17-22 Electrical Equipment 17
18-1 ~ 18-10 Emission Control System 18
19-1 ~ 19-2 Electrical Diagram
19
Homepage

Serial Number
Home page Contents

1. General Information
1-1
Symbols and Marks····························1-1
General Safety····································1-2
Before Servicing·································1-3
Specifications·····································1-9
Torque Values···································· 1-12
Trouble Diagnosis······························ 1-14
Lubrication Points ····························· 1-18
Symbols and Marks
Symbols and marks are used in this manual to indicate what and where the special service is needed. If
supplemental information is needed for these symbols and marks, explanations will be added in the text
instead of using the symbols or marks.
Warning Means that serious injury or loss of life may happen if procedures are not
correctly 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).
Homepage Contents
1

1. General Information
1-2
General Safety
Carbon Monoxide
Before you start the engine, make sure the place
is well ventilated. Never start the engine in an
unventilated place. If you have to start the engine
in an unventilated place, an exhaust fume
extractor is needed.
Caution
Exhaust fume contains toxic gas which may
cause one to lose consciousness and even result
in loss of life.
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 the
children.
Used Engine Oil
Caution
Prolonged contact with the used engine oil (or
transmission oil) may cause skin cancer although
it might not be verified yet. We recommend that
you wash your hands with soap right after
contacting. Keep the used oil beyond reach of the
children.
Hot Components
Caution
Components of the engine and exhaust system
can be extremely hot after engine running. They
remain very hot even after the engine has been
stopped for a period of time. Before performing
service work on these parts, wear the heat
insulation gloves or wait until the temperature
drops.
Battery
Caution
‧ Battery emits explosive gases; flame is strictly
prohibited. Keep the place well ventilated
when the battery is being charged.
‧ Battery contains sulfuric acid (electrolyte)
which can cause serious burns, be careful not
to spill it on your skin or eyes. If you get
battery fluid on your skin, flush it off with water
immediately. If you get battery fluid in your
eyes, flush it off immediately with water and
go to hospital to see an ophthalmologist
doctor.
‧ If you swallow the battery fluid by mistake,
drink a lot of water or milk, and take some
laxative such as Epsom salts or vegetable oil
and then go to see a doctor.
‧ Keep the battery and battery fluid beyond
reach of the children.
Brake Shoes
Do not use compressed air or brush to clean the
components of the brake system. Use a vacuum
cleaner or the equivalent to avoid dust drifting in
the air.
Caution
Inhaling brake shoes dust may cause disease or
even cancer of the respiratory system.
Brake Fluid
Caution
Brake fluid spilled on painted, plastic, or rubber
parts may cause damage to the parts. Place a
clean towel on the top of the parts for protection
when servicing the brake system. Keep the brake
fluid beyond reach of the children.
To this chapter contents

1. General Information
1-3
Before Servicing
yAlways use SANYANG genuine parts and
recommended oil. Using improper parts may
cause damage to or destruction of the vehicle.
ySpecial tools are designed for removal and
installation of component parts without
damaging them. Using wrong tools may result in
parts damage.
yWhen servicing this vehicle, use only metric
tools. Metric bolts, nuts, and screws are not
interchangeable with the Britain system, using
wrong tools and fasteners may damage this
vehicle.
yClean the outside of the parts or the cover
before removing it from the vehicle. 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 flash point
solvent, and then blow dry with compressed air.
Pay special attention to O-rings or oil seals
because most of the cleaning agents have bad
effect on them.
yNever bend or twist control cables to avoid
unsmooth control and premature worn out.
yRubber parts may become deteriorated when
old, and be damaged by solvent and oil easily.
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.
To this chapter contents

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
To this chapter contents

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
To this chapter contents

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.
To this chapter contents

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
To this chapter contents

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
To this chapter contents

1. General Information
1-9
Specifications
MAKER SANYANG MODEL LM25W5-6/7
Overall Length 2165 mm Front TELESCOPIC FORK
Overall Width 870 mm
Suspension
System Rear UNlT SWING
Overall Height 1395 mm Front 110 / 90-13 56P
Dimension
Wheel Base 1495 mm
Tire
Specifications Rear 130 / 70-13 57P
Front 79 kg
Rear 111 kg Front DISK (ø 240 mm)
Curb
Weight
Total 190 kg
Brake System
Rear DISK (ø 220 mm)
Passengers/Weight Two / 150 kg Max. Speed 128 km/hr
Front 134 kg Performance Climb Ability <27°
Rear 206 kg Primary
Reduction Belt
Weight
Total
Weight
Total 340 kg Secondary
Reduction Gear
Type 4-STROKE ENGINE Clutch Centrifugal, dry type
Installation and
arrangement Vertical, below center,
incline 80°
Reduction
Transmission CVT
Fuel Above 92 unleaded Speedometer 0 ~ 160 km/hr
Cycle/ Cooling 4-stroke/
Liquid-cooled Horn <110 dB/A
Bore 71 mm Muffler Expansion & Pulse
Type
Stroke 63.3 mm Exhaust Pipe Position and
Direction Right side, and
Backward
Cylinder
Number/Arrange
ment SINGLE CYLINDER Lubrication System Forced circulation &
splashing
Displacement 250.6 cc CO <2.0 g/km
Compression Ratio 10.5 : 1 HC <0.3 g/km
Max. HP 23.4 ps / 8000 rpm
Exhaust
Concentratio
n
NOx <0.15 g/km
Max. Torque 2.3 kg-m / 5500 rpm E.E.C. -
Ignition Full transistor ignition P.C.V. √
Engine
Starting System Electrical starter Catalytic reaction control
system √
To this chapter contents

1. General Information
1-10
Specifications
MAKER SANYANG MODEL LM25W5-P
LM25W7-7
Overall Length 2165 mm Front TELESCOPIC FORK
Overall Width 870 mm
Suspension
System Rear UNlT SWING
Overall Height 1395 mm Front 110 / 90-13 56P
Dimension
Wheel Base 1495 mm
Tire
Specifications Rear 130 / 70-13 57P
Front 79 kg
Rear 111 kg Front DISK (ø 240 mm)
Curb
Weight
Total 190 kg
Brake System
Rear DISK (ø 220 mm)
Passengers/Weight Two / 150 kg Max. Speed 128 km/hr
Front 134 kg Performance Climb Ability <27°
Rear 206 kg Primary
Reduction Belt
Weight
Total
Weight
Total 340 kg Secondary
Reduction Gear
Type 4-STROKE ENGINE Clutch Centrifugal, dry type
Installation and
arrangement Vertical, below center,
incline 80°
Reduction
Transmission CVT
Fuel Above 92 unleaded Speedometer 0 ~ 160 km/hr
Cycle/ Cooling 4-stroke/
Liquid-cooled Horn 93~112 dB/A
Bore 71 mm Muffler Expansion & Pulse
Type
Stroke 63 mm Exhaust Pipe Position and
Direction Right side, and
Backward
Cylinder
Number/Arrange
ment SINGLE CYLINDER Lubrication System Forced circulation &
splashing
Displacement 249.4 cc CO <2.0 g/km
Compression Ratio 10.5 : 1 HC <0.3 g/km
Max. HP 23.4 ps / 8000 rpm
Exhaust
Concentratio
n
NOx <0.15 g/km
Max. Torque 2.3 kg-m / 5500 rpm E.E.C. -
Ignition Full transistor ignition P.C.V. √
Engine
Starting System Electrical starter Catalytic reaction control
system √
To this chapter contents

1. General Information
1-11
Specifications
MAKER SANYANG MODEL LM30W-6/T
Overall Length 2165 mm Front TELESCOPIC FORK
Overall Width 870 mm
Suspension
System Rear UNlT SWING
Overall Height 1395 mm Front 110 / 90-13 56P
Dimension
Wheel Base 1495 mm
Tire
Specifications Rear 130 / 70-13 57P
Front 79 kg
Rear 111 kg Front DISK (ø 240 mm)
Curb
Weight
Total 190 kg
Brake System
Rear DISK (ø 220 mm)
Passengers/Weight Two / 150 kg Max. Speed 128 km/hr
Front 134 kg Performance Climb Ability <27°
Rear 206 kg Primary
Reduction Belt
Weight
Total
Weight
Total 340 kg Secondary
Reduction Gear
Type 4-STROKE ENGINE Clutch Centrifugal, dry type
Installation and
arrangement Vertical, below center,
incline 80°
Reduction
Transmission CVT
Fuel Above 92 unleaded Speedometer 0 ~ 160 km/hr
Cycle/ Cooling 4-stroke/
Liquid-cooled Horn 93~112 dB/A
Bore 73 mm Muffler Expansion & Pulse
Type
Stroke 63 mm Exhaust Pipe Position and
Direction Right side, and
Backward
Cylinder
Number/Arrange
ment SINGLE CYLINDER Lubrication System Forced circulation &
splashing
Displacement 263.7 cc CO <2.0 g/km
Compression Ratio 10.1 : 1 HC <0.3 g/km
Max. HP 23.3 ps / 7500 rpm
Exhaust
Concentratio
n
NOx <0.15 g/km
Max. Torque 2.5 kg-m / 5500 rpm E.E.C. -
Ignition Full transistor ignition P.C.V. √
Engine
Starting System Electrical starter Catalytic reaction control
system √
To this chapter contents

1. General Information
1-12
Torque Values
The torque values listed in below are for more important tightening torque values. Please see standard
values for those 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
Camshaft Chain Tensioner 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 0.8~1.2
Mission filling bolt 1 10 1.0~1.4
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 bolt 7 6 0.8~1.2
Mission case bolt 7 8 2.6~3.0
Muffler mounting bolt 3 10 3.2 ~3.8
Muffler mounting nut 2 8 1.0 ~1.2
To this chapter contents

1. General Information
1-13
Frame Torque Values
Item Q’ty Thread Dia. (mm) Torque Value (Kg-m) Remarks
Mounting bolt for steering handle
post 1 10 4.0~5.0
Lock nut for steering stem 1 BC1 1.0~2.0
Steering top cone race 1 BC1 2.0~3.0
Front wheel axle nut 1 12 5.0~7.0
Rear wheel axle nut 1 16 11.0~13.0
Front cushion mounting bolt 4 10 3.5~4.5
Rear cushion upper connection bolt 1 10 3.5~4.5
Rear cushion under connection bolt 1 8 2.4~3.0
Rear fork mounting bolt 2 10 4.0~5.0
Brake hose bolt 2 10 3.0~4.0
Brake air-bleeding valve 1 6 0.8~1.0
Front brake disc mounting bolt 5 8 4.0~4.5
Rear brake disc mounting bolt 5 8 4.0~4.5
Brake clipper mounting bolt 2 8 2.9~3.5
Engine hanger link bolt 2 12 7.5~9.5 On frame side
Engine hanger link nut 1 12 7.5~9.5 On engine side
Main standard nut 1 10 4.0~5.0
Air cleaner bolts 2 6 1.0~1.4
To this chapter contents

1. General Information
1-14
Trouble Diagnosis
A. Engine hard to start or can not be started
To this chapter contents
Check and adjustment Failure condition Possible causes
Loosen carburetor drain bolt
to check if there is gasoline
inside the carbureto
r
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 ground.
Perform cylinder
compression pressure test.
Check if sparks Weak sparks, no spark
at all
Cylinder compression
pressure normal
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
1. No fuel in fuel tank
2. Check if the pipes, fuel tank to carburetor
and intake vacuum, are clogged.
3. Float valve clogged
4. Lines in fuel tank evaporation system
clogged
5. Malfunction of fuel pump
6. Loosen or damaged fuel pump vacuum
hose
7. Fuel filter clogged
1. Malfunction of spark plug
2. Spark plug foul
3. Malfunction of CDI set
4. Malfunction of AC generator
5. Ignition coil is in open or short circuit
6. Ignition coil leads open or short circuit
7. Malfunction of main switch
1. Piston ring seized
2. Malfunction of cylinder valves
3. Worn cylinder and piston ring
4. Cylinder gasket leak
5. Sand hole in compression parts
1. Malfunction of throttle valve operation
2. Air sucked into intake manifold
3. Incorrect ignition timing
1. Fuel level in carburetor too high
2. Malfunction of throttle valve operation
3. Throttle valve opening too wide
1. Malfunction of automatic by- starter

1. General Information
1-15
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 gauge)
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
1. Air cleaner clogged
2. Poor fuel supply
3. Lines in fuel tank evaporation system
clogged
4. Exhaust pipe clogged
5. Fuel level too low in carburetor
6. Fuel nozzle clogged in carburetor.
1. Malfunction of CDI
2. Malfunction of AC alternator
1. Cylinder & piston ring worn out
2. Cylinder gasket leaked
3. Sand hole in compression parts
4. Valve deterioration
5. Seized piston ring
1. Remove foreign
1. Remove dirt
2. Incorrect spark plug heat range
1. Piston and cylinder worn out
2. Lean mixture
3. Poor fuel quality
4. Too much carbon deposited in
combustion chamber
5. Ignition timing too advanced
6. Poor circuit on the cooling system
Normal Engine overheat
Continually drive in
acceleration or high speed
1. Too much carbon deposited in
combustion chamber
2. Lean mixture
3. Poor fuel quality
4. Ignition timing too advanced
To this chapter contents