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4-4
4
YFM70KPXK / YFM70KPAK / YFM70KPHK /
YFM70KPSK / YFM70KPLK
The warning light comes on in red when the en-
gine is overheating. If the red light comes on, stop
the vehicle as soon as it is safe to do so and allow
the engine to idle for about 10 minutes. If the
warning light does not go off, stop the engine and
allow it to cool. (See page 8-67.)
TIPWhen the key is turned to “ ” (on), the warning
light will come on in purple. EBU29933Fuel level warning light “ ” (YFM70KDXK /
YFM70KDHK)
This warning light comes on when the fuel level
drops below approximately 4.0 L (1.06 US gal,
0.88 Imp.gal). When this occurs, refuel as soon as
possible.
The electrical circuit of the warning light can be
checked by setting the engine stop switch to “ ”
and turning the key to “ ” (on). The warning light
should come on for a few seconds, and then go
off. If the warning light does not come on initially when
the key is turned to “ ” (on), or if the warning
light remains on, have a Yamaha dealer check the
electrical circuit.
EBU27288Engine trouble warning light “ ”
The electrical circuit of the warning light can be
checked by turning the key to “ ” (on). The
warning light should come on for a few seconds,
and then go off.
If the warning light does not come on initially when
the key is turned to “ ” (on), or if the warning
light remains on, have a Yamaha dealer check the
vehicle.
YFM70KDXK / YFM70KDHK
This warning light comes on or flashes when an
electrical circuit monitoring the engine is not work-
ing correctly. When this occurs, have a Yamaha
dealer check the self-diagnosis system.
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4-5
4YFM70KPXK / YFM70KPAK / YFM70KPHK /
YFM70KPSK / YFM70KPLK
This warning light comes on or flashes if a problem
is detected in the electrical circuit monitoring the
engine. When this occurs, the display will indicate
an error code (see page 4-11). Have a Yamaha
dealer check the self-diagnosis system.
EBU30571Electric Power Steering warning light “EPS”
(for EPS model)
This warning light comes on when the key is
turned to “ ” (on), and then goes off once the
engine is started. If the warning light remains on or
comes on after the engine is started, the EPS sys-
tem may not be working correctly. When this oc-
curs, have a Yamaha dealer check the EPS
system.
The electrical circuit of the warning light can be
checked by turning the key to “ ” (on). If the
warning light does not come on, have a Yamaha
dealer check the electrical circuit.
TIP
If the engine is stopped using the engine stop
switch and the key is in the “ ” (on) position,
the EPS warning light comes on to indicate that
the power assistance for the steering is not
functioning.
If the steering load is too heavy (i.e., excessive
steering use when the ATV is traveling at a slow
speed), the power assist is reduced to protect
the EPS motor from overheating. EBU38280Four-wheel drive indicators
Four-wheel drive indicator light “ ”
(YFM70KDXK / YFM70KDHK)
This indicator light comes on when the drivetrain
is set to “4WD” (four-wheel drive).TIPDue to the synchronizing mechanism in the differ-
ential gear case, the light may not come on until
the ATV starts moving.
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6-4
6
TIPWhen in reverse, the reverse indicator light
should come on. If the indicator light does not
come on, have a Yamaha dealer check the elec-
trical circuit.
Due to the synchronizing mechanism in the en-
gine, the indicator light may not come on until
the ATV starts moving. 4. Check behind for people or obstacles, and
then release the brake pedal.
5. Open the throttle lever gradually and continue to watch to the rear while backing.EBU36861Engine break-inThere is never a more important period in the life
of your engine than the first 240 km (150 mi) or 20
hours of operation. For this reason, you should fol-
low the engine break-in instructions carefully.
Since the engine is brand new, do not put an ex-
cessive load on it for the first 240 km (150 mi) or
20 hours. During this period the various parts in
the engine wear and polish themselves to the cor-
rect operating clearances. Avoid prolonged full-
throttle operation or any condition that might re-
sult in engine overheating. 0–120 km (0–75 mi) or 0–10 hours
Avoid prolonged operation above 1/2 throttle.
Vary the speed of the ATV regularly. Do not oper-
ate it at one set throttle position.
120–240 km (75–150 mi) or 10–20 hours
Avoid prolonged operation above 3/4 throttle. Rev
the engine freely, but do not use full throttle at any
time.
240 km (150 mi) or 20 hours and beyond
The ATV can now be operated normally.
NOTICEECB00221If any engine trouble should occur during the
engine break-in period, immediately have a
Yamaha dealer check the ATV. EBU27322ParkingWhen parking the ATV, stop the engine, and shift
the drive select lever into the park position.
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8-39
8
case. Never operate the engine with the air
filter element removed. Doing so would al-
low unfiltered air to enter the engine, caus-
ing rapid engine wear and possible engine
damage. Additionally, the fuel injection
system would be affected resulting in poor
engine performance and possible over-
heating.
[ECB00763]
12. Install the seat.TIPEach 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 throttle body and the rubber joint man-
ifold fittings for an air-tight seal. Tighten all fittings
securely to avoid the possibility of unfiltered air
entering the engine. EBU28905Cleaning the spark arresterBe sure the exhaust pipe and muffler are cool be-
fore cleaning the spark arrester.
WARNING
EWB02342Always let the exhaust system cool prior to
touching exhaust components.
Do not start the engine with the spark arrester
removed. Sparks or exhaust particulate can
cause eye injury, burns, or start a fire. 1. Remove the tailpipe bolts.
2. Remove the tailpipe by pulling it out of the
muffler, and then remove the gasket.1. Gasket
2. Spark arrester
3. Tailpipe
4. Tailpipe bolt
3
2
4
1
4
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Page 165 of 180
8-67
8
Engine overheating
WARNING
EWB02291Wait 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 put a thick rag over the cap when opening.
Allow any remaining pressure to escape before completely removing the cap. TIP
Tap water can be used in an emergency. Change to the recommended coolant as soon as possible.
The engine will tend to overheat if the radiator is caked with mud, or if the ATV is overloaded. 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 check
and repair the cooling system.Add coolant. (See TIP.)
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.
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