2016 YAMAHA GRIZZLY 450 check engine

8-15
8
3. Remove the spark plug as shown, with the
spark plug wrench included in the owner’s
tool 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).
TIPIf 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.
3. Measure the spark plug gap with a wire thick- ness gauge and, if necessary, adjust the gap
to specification.
1. Spark plug wrench
Specified spark plug:NGK/DR8EA
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8-16
8To install the spark plug
1. Clean the surface of the spark plug gasket and its mating surface, and then wipe off any
grime from the spark plug threads.
2. Install the spark plug with the spark plug wrench, and then tighten it to the specified
torque.
TIPIf a torque wrench is not available when installing
the 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 speci-
fied torque as soon as possible. 3. Install the spark plug cap.
4. Install the panel.EBU30241Engine oil and oil filter cartridgeThe engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter cartridge replaced at the intervals
specified in the periodic maintenance and lubrica-
tion chart.
To check the engine oil level1. Place the ATV on a level surface.
2. Remove panel E. (See page 8-10.)
3. Check the engine oil level on a cold engine.
1. Spark plug gapSpark plug gap: 0.6–0.7 mm (0.024–0.028 in)
Tightening torque:Spark plug:18 Nm (1.8 m·kgf, 13 ft·lbf)
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8
TIPIf the engine was started before checking the oil
level, be sure to warm up the engine sufficiently,
and then wait at least ten minutes until the oil set-
tles for an accurate reading. 4. Remove the engine oil filler cap, and thenwipe the engine oil dipstick off with a clean
rag.
5. Insert the dipstick into the filler hole (without screwing it in), and then remove it again to
check the oil level.
TIPThe engine oil should be between the tip of the
dipstick and the maximum level mark. 6. If the engine oil is not between the tip of thedipstick and the maximum level mark, add
sufficient oil of the recommended type to
raise it to the correct level. NOTICE: Be sure
the engine oil is at the correct level, other-
wise engine damage may result.
[ECB00852]
7. Insert the dipstick into the oil filler hole, and then tighten the engine oil filler cap.
1. Engine oil filler cap
1. Engine oil dipstick
2. Maximum level mark
3. Tip of the engine oil dipstick
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8

Make sure that no foreign material enters the
crankcase.
13. 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.
14. Turn the engine off, wait at least ten minutes, and then check the oil level and correct it if
necessary.
15. Install panel E.EBU30271Final gear oilThe final gear case must be checked for oil leak-
age before each ride. If any leakage is found, have
a Yamaha dealer check and repair the ATV. In ad-
dition, the final gear oil level must be checked and
the oil changed as follows at the intervals speci-
fied in the periodic maintenance and lubrication
chart.
To check the final gear oil level 1. Place the ATV on a level surface. 2. Remove the final gear oil filler bolt and its gas-
ket, and then check the oil level in the final
gear case. The oil level should be at the brim
of the filler hole.
3. If the oil is below the brim of the filler hole, add sufficient oil of the recommended type to
raise it to the correct level.
4. Check the oil filler bolt gasket for damage, and replace it if necessary.
5. Install the oil filler bolt and its gasket, and then tighten the bolt to the specified torque.
1. Final gear oil filler bolt
2. Gasket
3. Final gear oil
4. Correct oil level1
2
3
4
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8
6. Refill with the recommended final gear oil to
the brim of the filler hole as shown. NOTICE:
Be sure no foreign material enters the final
gear case.
[ECB00422]
TIPIf the recommended oil is not available, SAE80W-
90 API GL-5 Hypoid gear oil may be used instead. However, when using this oil, noise from the final
gear case may occur when applying the rear
brake.
7. Check the oil filler bolt gasket for damage,
and replace it if necessary.
8. Install the oil filler bolt and its gasket, and then tighten the bolt to the specified torque.
9. Check the final gear case for oil leakage. If oil is leaking, check for the cause.
10. Install the engine guard and the final gear case guard by installing the bolts, and then
tightening them to the specified torques.
1. Final gear oil filler bolt
2. Gasket
3. Final gear oil
4. Correct oil levelRecommended final gear oil:See page 10-1.1
2
3
4
Tightening torque: Final gear oil filler bolt:22 Nm (2.2 m·kgf, 16 ft·lbf)
Tightening torques: Engine guard bolt:7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Final gear case guard bolt: 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
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8-26
88. Check the differential gear case for oil leak-
age. If oil is leaking, check for the cause.
EBU23471CoolantThe 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.EBU27129To check the coolant level1. 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 panel C to access the coolant
reservoir. (See page 8-10.)
4. Remove the coolant reservoir cap, add cool- ant or distilled water to the maximum level
mark, install the reservoir cap, and then install
the panel. NOTICE: If coolant is not avail-
able, use distilled water or soft tap water
instead. Do not use hard water or salt wa-
Tightening torque:
Differential gear oil filler bolt:23 Nm (2.3 m·kgf, 17 ft·lbf)1. Maximum level mark
2. Minimum level mark
1
2
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8
ter since they are harmful to the engine. If
water has been used instead of coolant,
replace it with coolant as soon as possible,
otherwise 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,
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 8-65 for fur-
ther instructions. EBU23608To change the coolant
WARNING
EWB01891Wait 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
when opening. Allow any remaining pressure
to escape before completely removing the cap. 1. Place the ATV on a level surface.
2. Remove the front carrier and panel B. (See
page 8-10.)
3. Remove the radiator cap.
1. Coolant reservoir capCoolant reservoir capacity (up to the maxi-
mum level mark): 0.25 L (0.26 US qt, 0.22 Imp.qt)
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815. 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.
16. Start the engine, and then check for coolant leakage.
TIPIf any leakage is found, have a Yamaha dealer
check the cooling system. 17. Install the panels and the front carrier.EBU23647Cleaning 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.
2. Remove the seat. (See page 4-19.)
3. Remove the air filter case cover by unhookingthe air filter case cover holders.1. Air filter case check hose
U2LC62E0.book Page 30 Monday, May 11, 2015 2:28 PM