engine YAMAHA BANSHEE 350 2008 Owner's Guide

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EBU23470
Coolant
The coolant level should be checked before each
ride. In addition, the coolant must be changed at
the intervals specified in the periodic maintenance
and lubrication chart.
EBU23501
To check the coolant level
1. Place the ATV on a level surface.
NOTE:

The coolant level must be checked on a cold en-
gine since the level varies with engine tempera-
ture.
2. Check the coolant level in the coolant reser-
voir.
NOTE:

The coolant should be between the minimum and
maximum level marks.3. If the coolant is at or below the minimum level
mark, remove the seat. (See page 4-11.)
4. Open the coolant reservoir cover.
1. Maximum level mark
2. Minimum level mark
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5. Remove the reservoir cap, add coolant or dis-
tilled water to the maximum level mark, and
then install the reservoir cap.
CAUTION:

ECB00401

If coolant is not available, use distilled water
or soft tap water instead. Do not use hard wa-ter or salt water since it is harmful to the en-
gine.

If water has been used instead of coolant, re-
place it with coolant as soon as possible,
otherwise the cooling system will not be pro-
tected against frost and corrosion.

If water has been added to the coolant, have
a Yamaha dealer check the antifreeze con-
tent of the coolant as soon as possible, oth-
erwise the effectiveness of the coolant will
be reduced.
6. Close the coolant reservoir cover.
7. Install the seat.
NOTE:

If the engine overheats, see page 8-52 for further
instructions.
EBU23521
To change the coolant
WARNING

EWB01890
Wait for the engine and radiator to cool before
removing the radiator cap. You could be
burned by hot fluid and steam blown out under
pressure. Always place a thick rag over the cap
1. Coolant reservoir cover
2. Coolant reservoir cap
Coolant reservoir capacity (up to the maximum
level mark):
0.28 L (0.30 US qt) (0.25 Imp.qt)
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when opening. Allow any remaining pressure
to escape before completely removing the cap.
1. Place the ATV on a level surface.
2. Remove the radiator cover by removing the
bolts.
3. Place a container under the engine and re-
move the coolant drain bolts.4. Remove the radiator cap.
1. Radiator cover
2. Radiator cover bolt
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1. Coolant drain bolt
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tected against frost and corrosion.

If water has been added to the coolant, have
a Yamaha dealer check the antifreeze con-
tent of the coolant as soon as possible, oth-
erwise the effectiveness of the coolant will
be reduced.
12. Install the radiator cap, start the engine, let it
idle for several minutes, and then turn it off.
13. Remove the radiator cap to check the coolant
level in the radiator. If it is low, add sufficient
coolant until it reaches the top of the radiator,
and then install the radiator cap.
14. Start the engine, and then check for coolant
leakage.
NOTE:

If any leakage is found, have a Yamaha dealer
check the cooling system.
15. Install the radiator cover by installing the bolts.
EBU23621
Cleaning the air filter element
The air filter element should be cleaned at the in-
tervals specified in the periodic maintenance and
lubrication chart. Clean the air filter element more
frequently if you are riding in unusually wet or dustyareas.
NOTE:

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. Remove the seat. (See page 4-11.)
2. Remove the air filter case cover by unhooking
the holders.
1. Air filter case check hose
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5. Wash the sponge material gently but thor-
oughly in solvent.
WARNING

EWB01940
Always use parts cleaning solvent to clean the
sponge material. Never use low-flash-point
solvents or gasoline to clean the sponge mate-
rial because the engine could catch fire or ex-
plode.
6. Squeeze the excess solvent out of the sponge
material and let it dry.CAUTION:

ECB00440
Do not twist the sponge material when squeez-
ing it.
7. Check the sponge material and replace it if
damaged.
8. Apply a quality foam air filter oil to the sponge
material.
NOTE:

The sponge material should be wet but not drip-
ping.
9. Pull the sponge material over the air filter ele-
ment frame, and then install the lock plate by
1. Sponge material
2. Air filter element frame
3. Air filter element lock plate
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turning it.
10. Insert the air filter element into the air filter
case, and then install the air filter case cover
by hooking the holders onto the air filter case.
11. Install the seat.
NOTE:

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 rubberjoint 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.CAUTION:
ECB00460

Make sure that the air filter element is prop-
erly seated in the air filter case.

Never operate the engine with the air filter el-
ement removed. This will allow unfiltered air
to enter the engine, causing rapid engine
wear and possible engine damage. Addition-
ally, operation without the air filter element
will affect carburetor jetting with subsequent
poor performance and possible engine over-
heating.
EBU28310
Cleaning the spark arrester
Be sure the exhaust pipe and muffler are cool be-
fore cleaning the spark arrester.
1. Remove the screws.
1. Air filter element
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2. Remove the tailpipe by pulling it out of the
muffler.
3. Tap the tailpipe lightly, and then use a wire
brush to remove any carbon deposits from the
spark arrester portion of the tailpipe and inside
of the tailpipe housing.4. Make sure the gasket is properly positioned,
then insert the tailpipe into the muffler and
align the screw holes.
5. Install the screws and tighten them.
WARNING

EWB02340
Do not start the engine when cleaning the
spark arrester, otherwise it could cause injury
to the eyes, burns, carbon monoxide poison-
ing, possibly leading to death, and start a fire.
Always let the exhaust system cool prior to
1. Screw
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1. Tailpipe
2. Spark arrester
3. Gasket
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touching exhaust components.
EBU23992
Changing the carburetor settings
In extremely cold weather, it is necessary to
change the carburetor settings to maintain opti-
mum engine performance and to prevent engine
damage.
WARNING

EWB01990

Improperly servicing or adjusting the carbu-
retors could cause them to malfunction with
the possibility of an accident, or the carbure-
tors could leak fuel, which would be a fire
hazard.

Carburetor adjustments should only be per-
formed by a Yamaha dealer. Do not attempt
to perform these procedures unless you
have mechanical knowledge and the neces-
sary tools.

Do not perform this procedure while the en-
gine is hot. Place a rag under each carbure-
tor to catch any fuel. Wipe up any spilled fuel
completely.

After servicing the carburetors, always
check the throttle lever operation before op-erating the ATV to make sure it is working
correctly.
Standard settings

Main jet #200
Jet needle clip position 3rd groove
Pilot air screw 2.0 turns out
1. Main jet number
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2. Push the throttle lever forward until it stops
and hold it in this position.
3. Check through each carburetor window to see
if the punch mark on the throttle valve is at the
specified position.
4. If not, loosen the locknut and turn the adjust-
ing nut until the specified position is obtained.5. Move the throttle lever a few times and re-
check the position.
6. Install the fuel tank, side cover, radiator cover
and air filter case cover.
7. Connect the fuel hoses.
8. Install the seat.
EBU24020
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. Punch mark
2. Specified position: 0–1mm
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1. Adjusting nut
2. Locknut
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tion chart.
NOTE:


A diagnostic tachometer is needed to make this
adjustment.

The carburetor synchronization and the throttle
cable free play must be checked, and adjusted if
necessary, before adjusting the engine idling
speed.
1. Start the engine and warm it up.
NOTE:

The engine is warm when it quickly responds to the
throttle.
2. Attach the tachometer to the spark plug lead.
3. Turn in both pilot air screws until they lightly
seat.
4. Turn out both pilot air screws to specification.
(See the “Changing the carburetor settings”
section on the page 8-22.)5. Remove the seat. (See page 4-11.)
6. Check the engine idling speed and, if neces-
sary, adjust it to specification by turning the
throttle stop screws at the carburetors. To in-
crease the engine idling speed, turn the throt-
tle stop screws in direction (a), and to
decrease it, turn the screws in direction (b).
1. Pilot air screw
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