check engine YAMAHA GRIZZLY 125 2010 Owner's Manual

8-15
1
2
3
4
5
6
78
9
10
11

oil leakage. If oil is leaking, immediately turn
off the engine and check for the cause.
8. Turn the engine off, and then check the oil lev-
el and correct it if necessary.
EBU23843
Cleaning the engine and V-belt case air
filter elements
Both air filter elements should be cleaned at the
specified intervals in the periodic maintenance
chart.
Engine air filter element
TIP

There is a check hose at the bottom of the air filter
case. If dust or water collects in this hose, empty
the hose and clean the air filter element and air fil-
ter case.1. Place the ATV on a level surface.
2. Remove the seat. (See page 4-10.)
3. Remove the breather hose, and then loosen
the clamp screw.
1. Check hose
1

8-17
1
2
3
4
5
6
78
9
10
11

7. Wash the sponge material gently but thor-
oughly in solvent.
WARNING! Always use
parts cleaning solvent to clean the sponge
material. Never use low-flash-point sol-
vents or gasoline to clean the sponge ma-
terial because the engine could catch fire
or explode.
[EWB01941]

8. Squeeze the excess solvent out of the sponge
material and let it dry.
NOTICE:
Do not twist
the sponge material when squeezingit.
[ECB00441]

9. Check the sponge material and replace it if
damaged.
10. Apply Yamaha foam air filter oil or other qual-
ity foam air filter oil to the sponge material.
TIP

The sponge material should be wet but not drip-
ping.
11. Pull the sponge material over the air filter ele-
ment frame.
12. Install the washer and bolt.
NOTICE:
Be sure
to install the washer with the bent edge
facing outward as shown.
[ECB00452]

1. Bolt
2. Washer
3. Sponge material
4. Air filter element frame
3 4
21

8-18
1
2
3
4
5
6
78
9
10
11

13. Install the air filter element into the air filter
case.
NOTICE:
Make sure that the air filter
element is properly seated in the air filter
case. Never operate the engine with the air
filter element removed. This will allow un-
filtered air to enter the engine, causing rap-
id engine wear and possible engine
damage. Additionally, operation without
the air filter element will affect carburetor
jetting with subsequent poor performance
and possible engine overheating.
[ECB00461]

14. Install the air filter case cover by installing the
screws.15. Install the breather hose and then tighten the
clamp screw.
16. Install the seat.TIP

The air filter element should be cleaned every 20–
40 hours. It should be cleaned and lubricated more
often if the ATV is operated in extremely dusty ar-
eas. Each time the air filter element maintenance
is performed, check the air inlet of the air filter case
for obstructions. Check the air filter case rubber
joint to the carburetor fittings and the rubber joint
manifold fittings for an air-tight seal. Tighten all fit-
tings securely to avoid the possibility of unfiltered
air entering the engine.
V-belt case air filter element
1. Place the ATV on a level surface.
2. Remove the front carrier by removing the
bolts.
1. Washer
1

8-23
1
2
3
4
5
6
78
9
10
11

touching exhaust components.
EBU23930
V-belt case drain plug
After riding in water deep enough to allow it to en-
ter the V-belt case, remove this plug to drain the
water from the case.
TIP

If water drains from the V-belt case after removing
the plug, have a Yamaha dealer check the ATV as
the water may affect other engine parts.
EBU23940
Adjusting the carburetor
The carburetor should be checked and, if neces-
sary, adjusted at the intervals specified in the peri-
odic maintenance and lubrication chart. The
carburetor is an important part of the engine and
requires very sophisticated adjustment. Therefore,
most carburetor adjustments should be left to a
Yamaha dealer, who has the necessary profes-
sional knowledge and experience. The adjustment
described in the following section, however, may
be performed by the owner as part of routine main-
tenance.
NOTICE

ECB00480
The carburetor has been set and extensively
tested at the Yamaha factory. Changing these
settings without sufficient technical knowl-
edge may result in poor performance of or
damage to the engine.
EBU24000
Adjusting the engine idling speed
The engine idling speed must be checked and, if
necessary, adjusted as follows at the intervals
specified in the periodic maintenance and lubrica-
1. V-belt case drain plug
1

8-24
1
2
3
4
5
6
78
9
10
11

tion chart.
TIP

A diagnostic tachometer is needed to make this
adjustment.
1. Start the engine and warm it up.
TIP

The engine is warm when it quickly responds to the
throttle.
2. Attach the tachometer to the spark plug lead.
3. Check the engine idling speed and, if neces-
sary, adjust it to specification by turning the
throttle stop screw at the carburetor. To in-
crease the engine idling speed, turn the throt-
tle stop screw in direction (a), and to decrease
it, turn the screw in direction (b).
TIP

If the specified idling speed cannot be obtained as
described above, have a Yamaha dealer make the
adjustment.
EBU24045
Adjusting the throttle cable free play
The throttle cable free play should be checked
and, if necessary, adjusted at the intervals speci-
1. Throttle stop screw
Engine idling speed:
1650–1750 r/min
(a)(b) 1

8-25
1
2
3
4
5
6
78
9
10
11

fied in the periodic maintenance and lubrication
chart.
The throttle cable free play should measure 1.0–
3.0 mm (0.04–0.12 in) at the throttle lever. Period-
ically check the throttle cable free play and, if nec-
essary, adjust it as follows.
TIP

The engine idling speed must be checked, and ad-
justed if necessary, before adjusting the throttle ca-
ble free play.
1. Slide the rubber cover back.
2. Loosen the locknut.
3. To increase the throttle cable free play, turn
the throttle cable free play adjusting bolt in di-
rection (a). To decrease the throttle cable free
play, turn the adjusting bolt in direction (b).
4. Tighten the locknut.
5. Slide the rubber cover to its original position.
EBU24060
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 inter-
vals specified in the periodic maintenance and lu-
1. Rubber cover
2. Throttle cable free play adjusting bolt
3. Locknut
4. Throttle cable free play
4 3
2
1
(a) (b)

8-36
1
2
3
4
5
6
78
9
10
11

not use engine oil or any other lubricants
for the drive chain, as they may contain
substances that could damage the O-
rings.
[ECB00581]

EBU24901
Checking and lubricating the cables
The operation and the condition of all control ca-
bles should be checked before each ride, and the
cables and cable ends should be lubricated if nec-
essary. If a cable is damaged or does not move
smoothly, have a Yamaha dealer check or replace
it.
WARNING

EWB02581

Inspect cables frequently and replace if dam-
aged. Corrosion can result when the cable
sheaths become damaged, and cables can
also become frayed or kinked, which could
restrict the operation of controls and lead to
an accident or injury.

Always make sure all control cables work
smoothly before you begin riding in coldweather. If the control cables are frozen or do
not work smoothly, you could be unable to
control the ATV, which could lead to an acci-
dent or collision.
EBU28702
Checking and lubricating the front and
rear brake levers
The operation of the front and rear brake levers
should be checked before each ride, and the lever
pivots should be lubricated if necessary.
Front brake lever
Recommended lubricant:
Engine oil
Recommended lubricant:
Lithium-soap-based grease

8-49
1
2
3
4
5
6
78
9
10
11

EBU25791
Troubleshooting chart
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 ATV.
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 ATV.
The engine does not start.
Have a Yamaha dealer
check the ATV.
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 electrolyte level, recharge the
battery and check the lead connections.
DryWet
Open the throttle halfway and operate
the electric starter.

9-2
1
2
3
4
5
6
7
89
10
11

EBU25933
Storage
Short-term
Always store your ATV in a cool, dry place and, if
necessary, protect it against dust with a porous
cover.
NOTICE:
Storing the ATV in a poorly ven-
tilated room or covering it with a tarp while it is
still wet, will allow water and humidity to seep
in and cause rust. To prevent corrosion, avoid
damp cellars, stables (because of the presence
of ammonia) and areas where strong chemi-
cals are stored.

[ECB00721]

Long-term
Before storing your ATV for several months:
1. Follow all the instructions in the “Cleaning”
section of this chapter.
2. Turn the fuel cock lever to “OFF”.
3. Drain the carburetor float chamber by loosen-
ing the drain bolt; this will prevent fuel deposits
from building up. Pour the drained fuel into the
fuel tank.
4. Fill up the fuel tank and add fuel stabilizer (if
available) to prevent the fuel from deteriorat-
ing.5. Perform the following steps to protect the cyl-
inder, 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 sparking 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.
6. Lubricate all control cables and the pivoting
points of all levers and pedals.
7. Check and, if necessary, correct the tire air
pressure, and then block up the ATV so that Specified amount:
7.5 ml of stabilizer to each liter of fuel (or 1 oz
of stabilizer to each gallon of fuel)

INDEX
A
Accessories and loading ................................................ 6-6
Air filter elements, engine and V-belt filter
cleaning...................................................................... 8-15
B
Battery .................................................................. 5-6
,
8-39
Brake lever free play, adjusting the front...................... 8-27
Brake lever free play (rear), adjusting .......................... 8-31
Brake lever, front ............................................................ 4-4
Brake lever, rear............................................................. 4-4
Brake levers, checking and lubricating......................... 8-36
Brakes .......................................................................... 8-26
Brakes, front and rear .................................................... 5-3
Brake shoes, checking the front and rear .................... 8-26
C
Cables, checking and lubricating ................................. 8-36
Carburetor, adjusting.................................................... 8-23
Carrier, front ................................................................. 4-11
Carrier, rear .................................................................. 4-11
Chassis fasteners........................................................... 5-5
Cleaning ......................................................................... 9-1
D
Drive chain ..................................................................... 5-3
Drive chain, lubricating ................................................. 8-35
Drive chain slack .......................................................... 8-32
Drive select lever............................................................ 4-6
Drive select lever and driving in reverse ........................ 6-3
E
Engine break-in .............................................................. 6-4
Engine, cold start ........................................................... 6-1
Engine idling speed ...................................................... 8-23
Engine oil ............................................................... 5-3
,
8-9
Engine, starting a warm ................................................. 6-2
Engine stop switch ......................................................... 4-2
F
Front knuckle pivots, lubricating ................................... 8-38
Fuel ........................................................................ 4-6
,
5-3
Fuel cock ........................................................................ 4-8
Fuel tank cap.................................................................. 4-6
Fuse, replacing............................................................. 8-42
H
Handlebar switches ........................................................ 4-2
Headlight beam, adjusting............................................ 8-45
Headlight bulb, replacing.............................................. 8-43
Horn switch .................................................................... 4-2
I
Identification numbers .................................................. 11-1
Indicator lights ................................................................ 4-1
Instruments, lights and switches .................................... 5-6
K
Key identification number ............................................. 11-1
L
Label locations ............................................................... 1-1
Light switch .................................................................... 4-2