2017 YAMAHA GRIZZLY 350 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 cap
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/DR8EA
1. Spark plug gapSpark plug gap:0.6–0.7 mm (0.024–0.028 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.EBU2331CEngine 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 ten minutes until the oil set-
tles for an accurate reading. 3. Remove the engine oil filler cap, and then wipe the engine oil 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.
Tightening torque:
Spark plug:18 N·m (1.8 kgf·m, 13 lb·ft)1. Engine oil filler cap
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TIPThe engine oil should be between the tip of the
dipstick and the maximum level mark. 5. 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]
6. Check the O-ring for damage, and replace it if necessary.
7. Insert the dipstick into the oil filler hole, and then tighten the engine oil filler cap.
To change the engine oil (with or without oil fil-
ter cartridge replacement) 1. Place the ATV on a level surface.
2. Start the engine, warm it up for several minu- tes, and then turn it off.
3. Place an oil pan under the engine to collect the used oil.
4. Remove the engine oil filler cap, and then re- move the engine oil drain bolt and its gasket
to drain the oil from the crankcase.
1. O-ring
2. Engine oil dipstick
3. Maximum level mark
4. Tip of the engine oil dipstick
1234
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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. 10. Check the engine oil filler cap O-ring for dam-
age, and replace it if necessary. 11. Insert the dipstick into the oil filler hole, and
then tighten the engine oil filler cap.
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.
EBU23387Final 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.
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.
Recommended oil:
See page 10-1.
Oil quantity: Without oil filter cartridge replacement:2.20 L (2.33 US qt, 1.94 Imp.qt)
With oil filter cartridge replacement: 2.30 L (2.43 US qt, 2.02 Imp.qt)
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6. Wash the sponge material gently but thor-
oughly in solvent. WARNING! Always use
parts cleaning solvent to clean the sponge
material. Never use low-flash-point sol-
vents or gasoline to clean the sponge ma-
terial because the engine could catch fire
or explode.
[EWB01942]
7. Squeeze the excess solvent out of the sponge material and let it dry. NOTICE: Do
not twist the sponge material when
squeezing it.
[ECB00442]
8. Check the sponge material and replace it if damaged.
9. 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. 10. Pull the sponge material over the air filter ele- ment frame, and then install the lock plate.
11. Insert the air filter element into the air filter case, and then install the air filter case cover
by hooking the holders onto the air filter case.
NOTICE: Make sure that the air filter ele-
ment is properly seated in the air filter
1. Air filter element frame
2. Sponge material
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8case. Never operate the engine with the air
filter element removed. This will allow un-
filtered air to enter the engine, causing
rapid engine wear and possible engine
damage. Additionally, operation without
the air filter element will affect carburetor
jetting with subsequent poor performance
and possible engine overheating.
[ECB00462]
12. 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 carburetor fittings and the
rubber joint manifold fittings for an air-tight seal.
Tighten all fittings securely to avoid the possibility
of unfiltered air entering the engine. EBU27083Cleaning the spark arresterBe sure the exhaust pipe and muffler are cool be-
fore cleaning the spark arrester.
1. Remove the tailpipe bolts. 2. Remove the tailpipe by pulling it out of the
muffler.
3. Tap the tailpipe lightly, and then use a wire brush to remove any carbon deposits from
the spark arrester portion of the tailpipe and
inside of the tailpipe housing.
1. Tailpipe bolt
2. Tailpipe
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4. Insert the tailpipe into the muffler and align
the bolt holes.
5. Install the tailpipe bolts and tighten them to the specified torque.
WARNING
EWB02341Do not start the engine when cleaning the
spark arrester, otherwise it could cause injury
to the eyes, burns, carbon monoxide poison-
ing, possibly leading to death, and start a fire.
Always let the exhaust system cool prior to
touching exhaust components. EBU23921V-belt cooling duct check hoseIf dust or water collects in the V-belt cooling duct
check hose, remove the hose and clean it.
1. Tailpipe
2. Spark arresterTightening torque:Tailpipe bolt:10 N·m (1.0 kgf·m, 7.2 lb·ft)
1. V-belt cooling duct check hose (left front side of ATV)
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