check engine YAMAHA YFZ450R 2018 Owner's Manual

8-16
8
TIPWhen adding oil, be careful not to overfill the en-
gine oil tank; the oil level rises faster starting from
the half-level mark on the dipstick. 6. Check the O-ring for damage, and replace itif necessary.
7. Insert the dipstick into the engine oil tank filler hole, and then tighten the engine oil tank filler
cap. NOTICE: Make sure that the engine oil
tank filler cap is securely tightened; other-
wise, oil may seep out when the engine is
running.
[ECB00363]
To change the engine oil (with or without oil fil-
ter element replacement) 1. Place the ATV on a level surface.
2. Remove the engine guard by removing the bolts. 3. Start the engine, warm it up for several minu-
tes, and then turn it off.
4. Place an oil pan under the engine to collect the used oil.
5. Remove the engine oil tank filler cap, and then remove the engine oil tank drain bolt and
its gasket.
1. Engine guard
2. Bolt
2 21
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8
11. Install the crankcase engine oil drain bolt, the
engine oil tank drain bolt and their new gas-
ket, and then tighten the bolts to their speci-
fied torques.
12. Refill with the specified amount of the recom- mended engine oil through the engine oil tank
filler hole.
TIPBe sure to wipe off spilled oil on any parts after the
engine and exhaust system have cooled down.
NOTICEECB00301In order to prevent clutch slippage (since the
engine oil also lubricates the clutch), do not
mix any chemical additives. 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 CONSERV-
ING II” or higher.
 Make sure that no foreign material enters the
crankcase. 13. Check the engine oil tank filler cap O-ring for
damage, and replace it if necessary.
14. Install and tighten the engine oil tank filler cap.
15. Start the engine, and then let it idle for several minutes while checking it for oil leakage. If oil
is leaking, immediately turn the engine off and
check for the cause.
16. Turn the engine off, and then check the oil level and correct it if necessary.
17. Install the engine guard by installing the bolts, and then tighten them to the specified torque.
NOTICE: Be sure to apply LOCTITE
® to the
engine guard bolts before installing them.
[ECB00372]
Tightening torques: Crankcase engine oil drain bolt:20 N·m (2.0 kgf·m, 15 lb·ft)
Engine oil tank drain bolt: 20 N·m (2.0 kgf·m, 15 lb·ft)
Recommended oil: See page 10-1.
Oil quantity: Without oil filter element replacement:1.40 L (1.48 US qt, 1.23 Imp.qt)
With oil filter element replacement: 1.45 L (1.53 US qt, 1.28 Imp.qt)
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EBU29861CoolantThe 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. Have a Yamaha dealer
change the coolant. WARNING! Never attempt
to remove the radiator cap when the engine is
hot.
[EWB02671]
EBU27945
To check the coolant level 1. Place the ATV on a level surface.TIPThe 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.
TIPThe coolant should be between the minimum and
maximum level marks. 3. If the coolant is at or below the minimum levelmark, remove the coolant reservoir cap, add
coolant or distilled water to the maximum lev-
el mark, and then install the reservoir cap.
NOTICE: If coolant is not available, use
distilled water or soft tap water instead.
Do not use hard water or salt water since
they are harmful to the engine. If water has
Tightening torque:
Engine guard bolt:7 N·m (0.7 kgf·m, 5.2 lb·ft)1. Coolant reservoir cap
2. Maximum level mark
3. Minimum level mark
1
2
3
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8
been used instead of coolant, replace it
with coolant as soon as possible, other-
wise 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,
otherwise the effectiveness of the coolant
will be reduced.
[ECB01012]
TIP The radiator fan is automatically switched on or
off according to the coolant temperature in the
radiator.
 If the engine overheats, see page 8-52 for fur-
ther instructions.
EBU26809Cleaning the air filter elementThe air filter element should be cleaned at the in-
tervals specified in the periodic maintenance and
lubrication chart. Clean or, if necessary, replace
the air filter element more frequently if you are rid-
ing in unusually wet or dusty areas.TIPThere 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.
Coolant reservoir capacity (up to the maxi-
mum level mark):
0.25 L (0.26 US qt, 0.22 Imp.qt)1. Air filter case check hose
1
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8
8. Wash the sponge material gently but thor-
oughly in solvent. WARNING! Always use
parts cleaning solvent. Never use low-
flash-point solvents or gasoline because
the engine could catch fire or explode.
[EWB01943]
9. Squeeze the excess solvent out of the sponge material and let it dry. NOTICE: Do
not twist the sponge material when
squeezing it.
[ECB00442]
10. Check the sponge material and replace it if damaged.
11. Apply Yamaha foam air filter oil or other qual- ity foam air filter oil to the sponge material.TIPThe sponge material should be wet but not drip-
ping. 12. Pull the sponge material over the air filter ele-ment frame.
13. Apply all-purpose grease to the air filter ele- ment seat.
1. Sponge material
2. Air filter element frame
1
2
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8-25
8
17. Install the seat.
TIPThe 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 areas. Each time the air filter element main-
tenance 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 rub-
ber joint manifold fittings for an air-tight seal.
Tighten all fittings securely to avoid the possibility
of unfiltered air entering the engine. EBU30862Cleaning the spark arresterSelect a well-ventilated area free of combustible
materials and make sure the exhaust and muffler
are cool.
1. Remove the tailpipe cover by removing the bolts. 2. Remove the retainer by removing the bolts,
and then remove the tailpipe and gasket from
the muffler.
1. Tailpipe cover
2. Bolt2
1 2
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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.
EBU29704Adjusting the throttle lever free playPeriodically check the throttle lever free play and
adjust if necessary.1. Slide the rubber cover back.
2. Loosen the locknut.
Tightening torque:
Tailpipe cover bolt:8 N·m (0.8 kgf·m, 5.9 lb·ft)1. Rubber cover
2. Throttle lever free play adjusting bolt
3. Locknut
4. Throttle lever free playThrottle lever free play: 2.0–4.0 mm (0.08–0.16 in)
32
4
(a)(b)
1
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8-28
83. To increase the throttle lever free play, turn
the throttle lever free play adjusting bolt in di-
rection (a). To decrease the throttle lever free
play, turn the adjusting bolt in direction (b).
4. Tighten the locknut.
5. Slide the rubber cover to its original position.
EBU24061Valve clearanceThe 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-
brication chart.EBU29602BrakesReplacement of brake components requires pro-
fessional knowledge. Brake service should be
performed by a Yamaha dealer.
WARNING
EWB02572Operating with improperly serviced or adjust-
ed brakes could lead to a loss in braking ability
and an accident.
EBU24131Checking the front and rear brake padsThe front and rear brake pads must be checked
for wear at the intervals specified in the periodic
maintenance and lubrication chart.EBU29561Front brake pads
Each brake pad is provided with wear indicator
grooves, which allow you to check the brake pad
wear without having to disassemble the brake. To
check the brake pad wear, check the wear indica-
tor grooves. If a brake pad has worn to the point
that the wear indicator grooves have almost dis-
appeared, have a Yamaha dealer replace the
brake pads as a set.
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8-38
82. Wipe the drive chain dry.
3. Thoroughly lubricate the drive chain with a
special O-ring chain lubricant. NOTICE: Do
not use engine oil or any other lubricants
for the drive chain, as they may contain
substances that could damage the O-
rings.
[ECB00582]
EBU24905
Checking and lubricating the cablesThe 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
EWB02582
Inspect cables frequently and replace if
damaged. Corrosion can result when the ca-
ble 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 cold
weather. If the control cables are frozen or
do not work smoothly, you could be unable
to control the ATV, which could lead to an
accident or collision.
1. O-rings
1
1
Recommended lubricant:
Yamaha cable lubricant or other suitable cable lubricant
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8
EBU27695Troubleshooting chartsStarting problems or poor engine performance
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.There is no fuel.
Check the battery.
Supply fuel.
The engine does not start.
Check the battery.
Operate the electric starter.4. Compression
There is compression.
There is no compression.
The engine does not start.
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.
Check the compression.
DryWet
Operate the electric starter.
Have a Yamaha dealer check the ATV.
The engine does not start.
Check the ignition.
Operate the electric starter.2. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and have a Yamaha dealer charge
the battery if necessary.
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