2015 YAMAHA GRIZZLY 550 check engine

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EBU23214Checking the spark plugThe 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 ac-
cordance with the periodic maintenance and lubri-
cation chart. In addition, the condition of the spark
plug can reveal the condition of the engine.
To remove the spark plug1. Remove the spark plug cap. 2. 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).1. Spark plug cap1
1. Spark plug wrench
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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.
To install the spark plug1. 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.
Specified spark plug:
NGK/LMAR6A-9
1. Spark plug gapSpark plug gap:0.8–0.9 mm (0.031–0.035 in)
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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.EBU27468Engine 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. Check the engine oil level on a cold engine.
TIPIf the engine was started before checking the oil
level, be sure to warm up the engine sufficiently,
and then wait at least 10 minutes until the oil set-
tles for an accurate reading. 3. Remove the access cover by turning it coun- terclockwise.
4. Remove the engine oil dipstick, and then wipe it off with a clean rag.
Tightening torque:
Spark plug:13 Nm (1.3 m·kgf, 9.4 ft·lbf)1. Access cover
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5. Insert the dipstick completely into the oil filler
hole, and then remove it again to check the oil
level.
TIPThe engine oil should be between the minimum
and maximum level marks.
6. If the engine oil is at or below the minimumlevel mark, add sufficient oil of the recom-
mended type to raise it to the correct level.
NOTICE: Be sure the engine oil is at the
correct level, otherwise engine damage
may result.
[ECB00852]
7. Insert the dipstick completely into the oil filler hole.
8. Install the access cover by turning it clock- wise.
1. Engine oil dipstick
1. Maximum level mark
2. Minimum level mark
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811. Refill with the specified amount of the recom-
mended engine oil, and then insert the dip-
stick completely into the oil 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.
12. 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.
13. Turn the engine off, wait at least ten minutes, and then check the oil level and correct it if
necessary.
14. Install the access cover by turning it clock- wise.EBU27307Final 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 level1. Place the ATV on a level surface.
Recommended oil:
See page 10-1.
Oil quantity: Without oil filter cartridge replacement:2.00 L (2.11 US qt, 1.76 Imp.qt)
With oil filter cartridge replacement: 2.10 L (2.22 US qt, 1.85 Imp.qt)
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6. Check the oil filler bolt gasket for damage,
and replace it if necessary.
7. Install the oil filler bolt and its gasket, and then tighten the bolt to the specified torque.
8. 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.EBU27127To 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.
Recommended differential gear oil:See page 10-1.
Tightening torque: Differential gear oil filler bolt:23 Nm (2.3 m·kgf, 17 ft·lbf)
1. Maximum level mark
2. Minimum level mark
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83. If the coolant is at or below the minimum level
mark, remove panel D 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-
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 8-68 for fur-
ther instructions. 1. Coolant reservoir cap
2. Maximum level mark
3. Minimum level markCoolant reservoir capacity (up to the maxi-
mum level mark):
0.24 L (0.25 US qt, 0.21 Imp.qt)
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19. When coolant begins to flow out of the bolt
hole, tighten the cylinder head air bleed bolt
to the specified torque.
20. Start the engine and let it idle for ten minutes.
21. Rev the engine five times.
22. Pour additional coolant into the radiator until it is full. 23. Stop the engine and allow it to cool. If the
coolant level has dropped after the engine
has cooled, add sufficient coolant until it
reaches the top of the radiator, and then in-
stall the radiator cap.
24. Start the engine, and then check for coolant leakage.
TIPIf any leakage is found, have a Yamaha dealer
check the cooling system. 25. Install the V-belt cooling duct, and then tight-en the clamp screw.
26. Install the footboard by installing the bolts and nuts, and then tighten them to the speci-
fied torques.
1. Cylinder head air bleed boltTightening torque:Cylinder head air bleed bolt:10 Nm (1.0 m·kgf, 7.2 ft·lbf)
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