check engine YAMAHA VITY 125 2008 User Guide

PERIODIC MAINTENANCE AND MINOR REPAIR
6-8
6
EAU45590
Checking the spark plug The spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic mainte-
nance and lubrication chart. In addition,
the condition of the spark plug can re-
veal the condition of the engine.
To remove the spark plug
1. Place the vehicle on the center-
stand.
2. Remove panel A. (See page 6-6.)
3. Remove the spark plug cap.
4. Remove the spark plug as shown,
using the spark plug wrench,
which is located in the rear storage
compartment. (See page 3-9.)
To check the spark plug
1. Check that the porcelain insulator
around the center electrode of the
spark plug is a medium-to-light tan
(the ideal color when the vehicle is
ridden normally).
NOTE:If the spark plug shows a distinctly dif-
ferent color, the engine could be oper-
ating improperly. Do not attempt to
diagnose such problems yourself. In-
stead, have a Yamaha dealer checkthe vehicle.
2. Check the spark plug for electrode
erosion and excessive carbon or
other deposits, and replace it if
necessary.
To install the spark plug
1. Measure the spark plug gap with a
wire thickness gauge and, if nec-
essary, adjust the gap to specifica-
tion.
1. Spark plug wrench
1. Spark plug wrench
1
1
Specified spark plug:
NGK/CR7E
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-9
62. Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the
spark plug threads.
3. Install the spark plug with the
spark plug wrench, and then tight-
en it to the specified torque.
NOTE:If a torque wrench is not available when
installing a spark plug, a good estimate
of the correct torque is 1/4–1/2 turn
past finger tight. However, the spark
plug should be tightened to the speci-fied torque as soon as possible.
4. Install the spark plug cap.
5. Install the panel.
EAU45480
Engine oil The engine oil level should be checked
before each ride. In addition, the oil
must be changed at the intervals spec-
ified in the periodic maintenance and
lubrication chart.
The engine oil must also be changed at
the initial 1000 km (600 mi) and when
the oil change indicator color changes
from green to red. The oil change indi-
cator must be reset after the initial 1000
km (600 mi). (See page 3-2 for reset
procedures.)
To check the engine oil level
1. Place the vehicle on the center-
stand.NOTE:Make sure that the vehicle is positioned
straight up when checking the oil level.
A slight tilt to the side can result in afalse reading.
2. Start the engine, warm it up for
several minutes, and then turn it
off.
1. Spark plug gapSpark plug gap:
0.7–0.8 mm (0.028–0.031 in)
Tightening torque:
Spark plug:
13 Nm (1.3 m·kgf, 9.4 ft·lbf)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-10
6 3. Wait a few minutes until the oil set-
tles, remove the oil filler cap, wipe
the dipstick clean, insert it back
into the oil filler hole (without
screwing it in), and then remove it
again to check the oil level.
NOTE:The engine oil should be between theminimum and maximum level marks.
4. If the engine oil is below the mini-
mum level mark, add sufficient oil
of the recommended type to raise
it to the correct level.5. Insert the dipstick into the oil filler
hole, and then tighten the oil filler
cap.
To change the engine oil
1. Place the vehicle on the center-
stand.
2. Start the engine, warm it up for
several minutes, and then turn it
off.
3. Place an oil pan under the engine
to collect the used oil.
4. Remove the engine oil filler cap
and drain bolt to drain the oil from
the crankcase.
NOTE:Check the washer for damage and re-place it if necessary.5. Install the engine oil drain bolt, and
then tighten it to the specified
torque.
6. Refill with the specified amount of
the recommended engine oil, and
then install and tighten the engine
oil filler cap.
1. Engine oil filler cap
2. Dipstick
3. Maximum level mark
4. Minimum level mark
32
1 4
1. Engine oil drain bolt
Tightening torque:
Engine oil drain bolt
20 Nm (2.0 m·kgf, 14 ft·lbf)
Recommended engine oil:
See page 8-1.
Oil quantity:
1.00 L (1.06 US qt) (0.88 Imp.qt)
1
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-11
6
CAUTION:
ECA11670


Do not use oils with a diesel
specification of “CD” or oils of a
higher quality than specified. In
addition, do not use oils labeled
“ENERGY CONSERVING II” or
higher.


Be sure no foreign material en-ters the crankcase.
7. Start the engine, and then let it idle
for several minutes while checking
it for oil leakage. If oil is leaking, im-
mediately turn the engine off and
check for the cause.8. Turn the engine off, and then
check the oil level and correct it if
necessary.
9. Reset the oil change indicator.
(See page 3-2 for reset proce-
dures.)
NOTE:If the engine oil is changed before the
oil change indicator color changes from
green to red (i.e. before the periodic oil
change interval has been reached), the
oil change indicator must be reset after
the oil change for the next periodic oil
change to be indicated at the correcttime.
EAU20063
Final transmission oil The final transmission case must be
checked for oil leakage before each
ride. If any leakage is found, have a
Yamaha dealer check and repair the
scooter. In addition, the final transmis-
sion oil must be changed as follows at
the intervals specified in the periodic
maintenance and lubrication chart.
1. Start the engine, warm up the final
transmission oil by riding the
scooter for several minutes, and
then stop the engine.
2. Place the scooter on the center-
stand.
3. Place an oil pan under the final
transmission case to collect the
used oil.
4. Remove the final transmission oil
filler cap and final transmission
drain bolt to drain the oil from the fi-
nal transmission case.
1.“CD” specification
2.“ENERGY CONSERVING II”
1
2
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-13
63. Pull the air filter element out.
4. Insert a new air filter element into
the air filter case.
CAUTION:
ECA10480


Make sure that the air filter ele-
ment is properly seated in the
air filter case.


The engine should never be op-
erated without the air filter ele-
ment installed, otherwise the
piston(s) and/or cylinder(s) maybecome excessively worn.
5. Install the air filter case cover by in-
stalling the screws.
Cleaning the air filter check hoses1. Check the hoses on the rear side
of the air filter case for accumulat-
ed dirt or water.
2. If dirt or water is visible in the air fil-
ter check hoses, remove the
clamps from them, and then re-
move the plugs to drain the hoses.
Cleaning the V-belt case air filter el-
ement
1. Place the scooter on the center-
stand.
2. Remove the screws, and then pull
the V-belt case air filter element
cover outward and away from V-
belt case.
1. Air filter case cover
2. Screw
1. Air filter element
2 1
2
1
1. Air filter check hose
2. Clamp
3. Air filter check hose plug
1
23
1. V-belt case air filter element cover
2. Screw
2 1
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-15
6
EAU21382
Checking the throttle cable
free play The throttle cable free play should mea-
sure 3.0–5.0 mm (0.12–0.20 in) at the
throttle grip. Periodically check the
throttle cable free play and, if neces-
sary, have a Yamaha dealer adjust it.
EAU21401
Valve clearance The valve clearance changes with use,
resulting in improper air-fuel mixture
and/or engine noise. To prevent this
from occurring, the valve clearance
must be adjusted by a Yamaha dealer
at the intervals specified in the periodic
maintenance and lubrication chart.
EAU33600
Tires To maximize the performance, durabil-
ity, and safe operation of your vehicle,
note the following points regarding the
specified tires.
Tire air pressure
The tire air pressure should be checked
and, if necessary, adjusted before each
ride.
WARNING
EWA10500


The tire air pressure must be
checked and adjusted on cold
tires (i.e., when the temperature
of the tires equals the ambient
temperature).


The tire air pressure must be ad-
justed in accordance with the
riding speed and with the total
weight of rider, passenger, car-
go, and accessories approvedfor this model.
1. Throttle cable free play1ZAUM0051
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-20
6


Brake fluid may deteriorate paint-
ed surfaces or plastic parts. Al-
ways clean up spilled fluid
immediately.


As the brake pads wear, it is nor-
mal for the brake fluid level to grad-
ually go down. However, if the
brake fluid level goes down sud-
denly, have a Yamaha dealer
check the cause.
EAU22720
Changing the brake fluid Have a Yamaha dealer change the
brake fluid at the intervals specified in
the NOTE after the periodic mainte-
nance and lubrication chart. In addition,
have the oil seals of the brake master
cylinder and caliper as well as the
brake hose replaced at the intervals
listed below or whenever they are dam-
aged or leaking.

Oil seals: Replace every two
years.


Brake hose: Replace every four
years.
EAU23100
Checking and lubricating the
cables The operation of all control cables and
the condition of the cables should be
checked before each ride, and the ca-
bles and cable ends should be lubricat-
ed if necessary. If a cable is damaged
or does not move smoothly, have a
Yamaha dealer check or replace it.
WARNING
EWA10720
Damage to the outer sheath may in-
terfere with proper cable operation
and will cause the inner cable to
rust. Replace a damaged cable as
soon as possible to prevent unsafeconditions.
Recommended lubricant:
Engine oil
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-29
6
EAUT1980
Troubleshooting chart
WARNING
EWA10840
Keep away open flames and do not smoke while checking or working on the fuel system.
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.
There is no fuel.
Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the electric starter.2. Compression
There is compression.
There is no compression.
Check the ignition.
Have a Yamaha dealer
check the vehicle.
Remove the spark plug
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug.
Have a Yamaha dealer check the vehicle.
The engine does not start.
Have a Yamaha dealer
check the vehicle.
The engine does not start.
Check the battery.
Operate the electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and charge the battery if necessary.
DryWet
Operate the electric starter.
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SCOOTER CARE AND STORAGE
7-4
73. Perform the following steps to pro-
tect the cylinder, piston rings, etc.
from corrosion.
a. Remove the spark plug cap
and spark plug.
b. Pour a teaspoonful of engine oil
into the spark plug bore.
c. Install the spark plug cap onto
the spark plug, and then place
the spark plug on the cylinder
head so that the electrodes are
grounded. (This will limit spark-
ing during the next step.)
d. Turn the engine over several
times with the starter. (This will
coat the cylinder wall with oil.)
e. Remove the spark plug cap
from the spark plug, and then
install the spark plug and the
spark plug cap.
WARNING
EWA10950
To prevent damage or injury from
sparking, make sure to ground the
spark plug electrodes while turningthe engine over.4. Lubricate all control cables and the
pivoting points of all levers and
pedals as well as of the side-
stand/centerstand.
5. Check and, if necessary, correct
the tire air pressure, and then lift
the scooter so that both of its
wheels are off the ground. Alterna-
tively, turn the wheels a little every
month in order to prevent the tires
from becoming degraded in one
spot.
6. Cover the muffler outlet with a
plastic bag to prevent moisture
from entering it.
7. Remove the battery and fully
charge it. Store it in a cool, dry
place and charge it once a month.
Do not store the battery in an ex-
cessively cold or warm place [less
than 0 °C (30 °F) or more than 30
°C (90 °F)]. For more information
on storing the battery, see page
6-23.
NOTE:Make any necessary repairs beforestoring the scooter.
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INDEXAAcceleration and deceleration................. 5-3
Air filter and V-belt case air filter
elements ............................................. 6-12
Anti-theft alarm (optional)........................ 3-4
Auxiliary light bulb, replacing ................ 6-27BBattery................................................... 6-23
Brake fluid, changing ............................ 6-20
Brake fluid level, checking .................... 6-19
Brake lever, front..................................... 3-5
Brake lever, rear ..................................... 3-6
Brake levers, lubricating........................ 6-21
Brake pads and shoes, checking .......... 6-18
Braking .................................................... 5-3CCables, checking and lubricating .......... 6-20
Care ........................................................ 7-1
Carrier ................................................... 3-10
Catalytic converters ................................ 3-8
Centerstand and sidestand,
checking and lubricating ..................... 6-22
Cowlings and panels,
removing and installing ......................... 6-6DDimmer switch ........................................ 3-5EEngine break-in ....................................... 5-4
Engine oil ................................................ 6-9
Engine trouble warning light.................... 3-3FFinal transmission oil ............................ 6-11
Front brake lever free play, checking .... 6-17
Front fork, checking .............................. 6-22Fuel......................................................... 3-7
Fuel consumption, tips for reducing........ 5-4
Fuel gauge.............................................. 3-4
Fuel tank cap .......................................... 3-6
Fuse, replacing ..................................... 6-25
HHandlebar switches ................................ 3-5
Headlight bulb, replacing ...................... 6-25
Helmet holders ....................................... 3-9
High beam indicator light ........................ 3-2
Horn switch ............................................. 3-5IIdentification numbers ............................ 9-1
Ignition circuit cut-off system ................ 3-12
Indicator, indicator lights and
warning light ......................................... 3-2KKeyhole cover ......................................... 3-2
Key identification number ....................... 9-1LLuggage hook ....................................... 3-11MMain switch/steering lock........................ 3-1
Matte color, caution ................................ 7-1
Model label ............................................. 9-2PParking ................................................... 5-5
Part locations .......................................... 2-1
Periodic maintenance and lubrication
chart ..................................................... 6-2
Pre-operation check list .......................... 4-2RRear brake lever free play, adjusting .... 6-18Rear turn signal light and tail/brake
light ..................................................... 6-27
SSafe-riding points .................................... 1-4
Safety information ................................... 1-1
Seat ......................................................... 3-8
Self-diagnosis device .............................. 3-4
Sidestand .............................................. 3-11
Spark plug, checking ............................... 6-8
Specifications .......................................... 8-1
Speedometer unit .................................... 3-3
Starting off ............................................... 5-2
Starting the engine .................................. 5-1
Start switch.............................................. 3-5
Steering, checking................................. 6-23
Storage.................................................... 7-3
Storage compartments ............................ 3-9TThrottle cable free play, checking ......... 6-15
Throttle grip and cable,
checking and lubricating ..................... 6-21
Tires ...................................................... 6-15
Troubleshooting .................................... 6-28
Troubleshooting chart ........................... 6-29
Turn signal indicator light ........................ 3-2
Turn signal light bulb (front),
replacing ............................................. 6-26
Turn signal switch ................................... 3-5VValve clearance..................................... 6-15
Vehicle identification number .................. 9-1WWheel bearings, checking ..................... 6-23
Wheels .................................................. 6-17
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