2008 YAMAHA JOG50R check engine

EAUM1250
Panel A
T
o remove the panel
1. Open the storage compartment.
(See page 3-11.)
2. Remove the screw, and then take
the panel off.
1. Screw
2. Panel
To install the panel
1. Place the panel in the original
position, and then install the
screw.
2. Close the storage compartment.
EAU19621
Checking the spark plug
1. Spark plug gap
The spark plug is an important engine
component, which should be chec-
ked periodically, preferably by a
Yamaha dealer. Since heat and depo-
sits will cause any spark plug to
slowly erode, it should be removed
and checked in accordance with the
periodic maintenance and lubrication
chart. In addition, the condition of the
spark plug can reveal the condition of
the engine.
The porcelain insulator around the
center electrode of the spark plug
should be a medium-to-light tan (the
ideal color when the vehicle is riddennormally). If the spark plug shows a
distinctly different color, the engine
could be operating improperly. Do not
attempt to diagnose such problems
yourself. Instead, have a Yamaha
dealer check the vehicle.
If the spark plug shows signs of elec-
trode erosion and excessive carbon
or other deposits, it should be repla-
ced.
Before installing a spark plug, the
spark plug gap should be measured
with a wire thickness gauge and, if
necessary, adjusted to specification.
Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the
spark plug threads.
Spark plug gap:
0.6-0.7 mm (0.024-0.028 in)
Specified spark plug:
BR8HS/NGK (for CS50 CS50Z)
BPR4HS/NGK (for CS50M)
1
ZAUM0037
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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. Howe-
ver, the spark plug should be tighte-
ned to the specified torque as soon
as possible.
EAU20061
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 trans-
mission 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 centers-
tand.
3. Place an oil pan under the final
transmission case to collect the
used oil.
4. Remove the oil filler cap and
drain bolt to drain the oil from the
final transmission case.
1. Final transmission oil filler cap
2. Final transmission oil drain bolt
5. Install the final transmission oil
drain bolt, and then tighten it to
the specified torque.
6. Add the specified amount of the
recommended final transmission
oil, and then install and tighten
the oil filler cap.
Tightening torque:
Final transmission oil drain bolt:
18 Nm (1.8 m•kgf, 13.0 ft•lbf)
Tightening torque:
Spark plug:
20 Nm (2.0 m•kgf, 14.5 ft•lbf)
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EWA11310
s s
WARNING
●Make sure that no foreign
material enters the final trans-
mission case.
●Make sure that no oil gets on
the tire or wheel.
7. Check the final transmission case
for oil leakage. If oil is leaking,
check for the cause.
EAUS1200
Coolant (only for liquid-
cooled models)
The coolant level should be checked
before each ride. In addition, the coo-
lant must be changed at the intervals
specified in the periodic maintenance
and lubrication chart.
EAUM2101
To check the coolant level
1. Place the vehicle on a level surfa-
ce and hold it in an upright posi-
tion.
NOTE:
●The coolant level must be chec-
ked on a cold engine since the
level varies with engine tempera-
ture.
●Make sure that the vehicle is
positioned straight up when
checking the coolant level. A
slight tilt to the side can result in
a false reading.
2. Check the coolant level through
the check window.
NOTE:
The coolant should be between the
minimum and maximum level marks.
1. Coolant level window
2. Maximum level mark
3. Minimum level mark
3. If the coolant is at or below the
minimum level mark, remove the
cowling A. (See page 6-5.)
4. Open the reservoir cap, and then
add coolant to the maximum
level mark.
Coolant reservoir capacity:
0.25 L (0.26 US qt) (0.22 Imp.qt)
Recommended final transmission
oil:
See page 8-1.
Oil quantity:
0.11 L (0.12 US qt) (0.10 Imp.qt)
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1. Coolant reservoir cap
2. Maximum level mark
3. Minimum level mark
ECA10471
CAUTION:
●If coolant is not available, use
distilled water or soft tap water
instead. Do not use hard water
or salt water since it is harmful
to the engine.
●If water has been used instead
of coolant, replace it with coo-
lant as soon as possible, other-
wise the cooling system will
not be protected against frost
and corrosion.
●If water has been added to the
coolant, have a Yamaha dealer
check the antifreeze content ofthe coolant as soon as possi-
ble, otherwise the effective-
ness of the coolant will be
reduced.
EWA10380
s s
WARNING
Never attempt to remove the radia-
tor cap when the engine is hot.
5. Close the reservoir cap, and then
install the cowling.
EAU33030
Changing the coolantEWA10380
s s
WARNING
Never attempt to remove the radia-
tor cap when the engine is hot.
The coolant must be changed at the
intervals specified in the periodic
maintenance and lubrication chart.
Have a Yamaha dealer change the
coolant.
EAU40370
Air filter element
The air filter element must be cleaned
and replaced at the intervals specified
in the periodic maintenance and lubri-
cation chart. Have a Yamaha dealer
clean and replace the air filter ele-
ment.
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EAU21300
Adjusting the carburetor
The carburetor is an important part of
the engine and requires very sophisti-
cated adjustment. Therefore, all car-
buretor adjustments should be left to
a Yamaha dealer, who has the neces-
sary professional knowledge and
experience.
EAU21370
Adjusting the throttle cable
free play
1. Throttle cable free play
The throttle cable free play should
measure 2-5 mm (0.08-0.2 in) at the
throttle grip. Periodically check the
throttle cable free play and, if neces-
sary, adjust it as follows.
NOTE:
The engine idling speed must be
correctly adjusted before checking
and adjusting the throttle cable free
play.
1. Loosen the locknut.
1. Locknut
2. Adjusting nut
2. To increase the throttle cable free
play, turn the adjusting nut in
direction (a). To decrease the
throttle cable free play, turn the
adjusting nut in direction (b).
3. Tighten the locknut.
1
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ECA10590
CAUTION:
If any damage is found or the front
fork does not operate smoothly,
have a Yamaha dealer check or
repair it.
EAU23280
Checking the steering
Worn or loose steering bearings may
cause danger. Therefore, the opera-
tion of the steering must be checked
as follows at the intervals specified in
the periodic maintenance and lubrica-
tion chart. 1. Place a stand under the engine to raise the front wheel off the
ground.
EWA10750
s s WARNING
Securely support the vehicle so
that there is no danger of it falling
over.
2. Hold the lower ends of the front fork legs and try to move them
forward and backward. If any free
play can be felt, have a Yamaha
dealer check or repair the stee-
ring.

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EAU25921
Troubleshooting charts
Starting problems or poor engine performanceEWA10840
s s
WARNING
Keep away open flames and do not smoke while checking or working on the fuel system.
PERIODIC MAINTENANCE AND MINOR REPAIR
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6
Check the fuel level in
the fuel tank.
1. FuelThere 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. CompressionThere 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. IgnitionWipe 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. BatteryThe engine turns over
quickly.
The engine turns over
slowly.The battery is good.
Check the battery lead connections,
and charge the battery if necessary.
Dry
We tOpen the throttle halfway and operate
the electric starter.
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Engine overheating (for CS50Z)EWA10400
s s
WARNING
●Do not remove the radiator cap when the engine and radiator are hot. Scalding hot fluid and steam may be
blown out under pressure, which could cause serious injury. Be sure to wait until the engine has cooled.
●After removing the radiator cap retaining bolt, place a thick rag, like a towel, over the radiator cap, and then
slowly rotate the cap counterclockwise to the detent to allow any residual pressure to escape. When the his-
sing sound has stopped, press down on the cap while turning it counterclockwise, and then remove the cap.
PERIODIC MAINTENANCE AND MINOR REPAIR
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6
Wait until the
engine has cooled.Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.
The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer checkand repair the cooling system.
Add coolant. (See NOTE.)
Start the engine. If the engine overheats again, have a
Yamaha dealer check and repair the cooling system.
There is
leakage.
There is
no leakage.
NOTE:
If coolant is not available, tap water can be temporarily used instead, provided that it is changed to the recommended
coolant as soon as possible.
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