check engine YAMAHA YFZ450 2007 User Guide
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25 Engine oil
Change.
Check ATV for oil leakage, and correct if neces-
sary.
√ √√√
26Engine oil filter ele-
ment
Replace.
√√√
27 Cooling system
Check coolant level and ATV for coolant leakage,
and correct if necessary.
√√√√√
Replace coolant. Every 2 years
28
*
Moving parts and
cables
Lubricate.
√√√√
29
*
Throttle lever hous-
ing and cable
Check operation and correct if necessary.
Check throttle cable free play and adjust if neces-
sary.
Lubricate throttle lever housing and cable.
√√√√√
30
*
Exhaust system
Check for leakage and replace gasket(s) if neces-
sary.
Check for looseness and tighten all screw clamps
and joints if necessary.
√√√
31 Spark arrester
Clean.
√√√
32
*
Front and rear brake
switches
Check operation and correct if necessary.
√√√√√
33
*
Lights and switches
Check operation and correct if necessary.
Adjust headlight beams.
√√√√√
NO. ITEMCHECK OR MAINTENANCE
JOBINITIAL EVERY
Whichev-
er comes
firstmonth 1 3 6 6 12
km
(mi)320
(200)1200
(750)2400
(1500)2400
(1500)4800
(3000)
hours 20 75 150 150 300
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To install the panel1. Place the panel in the original position, and
then install the quick fastener screw and the
bolts.
2. Install the seat.
EBU23241
Checking the spark plug
The spark plug is an important engine component,
which is easy to check. Since heat and deposits
will cause any spark plug to slowly erode, the spark
plug should be removed and checked in accor-
1. Bolt
1
1. Projection
2. Slot
1
1 22
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kit.
To check the spark plug
1. Check that the porcelain insulator around the
center electrode of the spark plug is a medi-
um-to-light tan (the ideal color when the ATV
is ridden normally).
NOTE:
If the spark plug shows a distinctly different color,
the engine could be operating improperly. Do not
attempt to diagnose such problems yourself. In-
stead, have a Yamaha dealer check the ATV.
2. Check the spark plug for electrode erosionand excessive carbon or other deposits, and
replace it if necessary.
To install the spark plug
1. Measure the spark plug gap with a wire thick-
ness gauge and, if necessary, adjust the gap
to specification.
1. Spark plug wrench
1
Specified spark plug:
NGK/CR8E
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
1. Spark plug gap
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2. Clean the surface of the spark plug gasket
and its mating surface, and then wipe off any
grime from the spark plug threads.
3. Install the spark plug with the spark plug
wrench, and then tighten it to the specified
torque.
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. However, the spark
plug should be tightened to the specified torque as
soon as possible.
4. Install the spark plug cap.
5. Place the fuel tank in the original position, and
then install the bolt.
6. Remove the fuel tank cap by turning it coun-
terclockwise.
7. Place the panel in the original position.8. Install the fuel tank cap by turning it clockwise.
9. Install the bolts and the quick fastener screws.
10. Install the seat.
EBU23303
Engine oil and oil filter element
The engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter element replaced at the intervals spec-
ified in the periodic maintenance and lubrication
chart. Tightening torque:
Spark plug:
12.5 Nm (1.25 m·kgf, 9.0 ft·lbf)
1. Projection
2. Slot
21
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To check the engine oil level
1. Place the ATV on a level surface.
2. Start the engine, warm it up until the engine oil
has reached a normal temperature of 40 °C
(104 °F), let it continue to idle for ten seconds
or more, and then turn the engine off.
NOTE:
To achieve the proper engine oil temperature for
an accurate oil level reading, the engine must have
first completely cooled down, and then warmed up
again for several minutes to normal operating tem-
perature.
3. Remove the engine oil tank filler cap, wipe the
dipstick off with a clean rag.
4. Insert the dipstick into the filler hole (without
screwing it in), and then remove it again to
check the oil level.
NOTE:
The engine oil should be between the minimum
and maximum level marks.
5. If the engine oil is at or below the minimum
level mark, add sufficient oil of the recom-
mended type through the engine oil tank filler
hole to raise it to the correct level.
1. Engine oil tank filler cap
2. Dipstick
3. Engine oil tank
4. Engine oil filler cap
5. Maximum level mark
6. Minimum level mark
4 3 1 1
2
5
6
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6. Remove the engine oil tank filler cap and the
engine oil tank drain bolt.7. Check the washers for damage, and replace if
necessary.NOTE:
Skip steps 8–11 if the oil filter element is not being
replaced.
8. Remove the oil filter element cover by remov-
ing the bolts, and then remove the oil filter el-
ement.
1. Crankcase engine oil drain bolt
1
1. Engine oil tank drain bolt
1
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9. Check the O-rings for damage, and replace
them if necessary.10. Install a new oil filter element and the O-rings.NOTE:
Make sure that the O-rings are properly seated.
11. Install the oil filter element cover by installing
the bolts, and then tighten them to the speci-
fied torque.
12. Install the crankcase engine oil drain bolt and
1. Oil filter element cover
2. Bolt
1 2
1. Oil filter element
2. O-ring
Tightening torque:
Oil filter element cover bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
1
2 2
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crankcase.
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 lev-
el and correct it if necessary.
17. Install the engine guard by installing the bolts,
and then tighten them to the specified torque.
CAUTION:
ECB00370
Be sure to apply LOCTITE® to the engine
guard bolts before installing them.
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.
EBU23490
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. Tightening torque:
Engine guard bolt:
7 Nm (0.7 m·kgf, 5.1 ft·lbf)
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3. If the coolant is at or below the minimum level
mark, remove panel A. (See page 8-8.)
4. Remove the reservoir cap, add coolant or dis-
tilled water to the maximum level mark, install
the reservoir cap, and then install the panel.CAUTION:
ECB00400
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 engine may not be sufficiently
cooled and 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 con-
tent of the coolant as soon as possible, oth-
erwise the effectiveness of the coolant will
be reduced.
NOTE:
If the engine overheats, see page 8-52 for further
instructions.
EBU23560
To change the coolant
WARNING
EWB01890
Wait for the engine and radiator to cool before
1. Maximum level mark
2. Minimum level mark
3. Coolant reservoir
4. Coolant reservoir cap
Coolant reservoir capacity (up to the maximum
level mark):
0.29 L (0.31 US qt) (0.26 Imp.qt)
1
24
3
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otherwise the engine may not be sufficiently
cooled and 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 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 panel.
EBU23701
Cleaning the air filter element
The air filter element should be cleaned at the in-
tervals specified in the periodic maintenance andlubrication chart. Clean the air filter element more
frequently if you are riding in unusually wet or dusty
areas.
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
1