2015 YAMAHA GRIZZLY 350 engine

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EBU21745Periodic maintenance chart for the emission control systemTIPFor ATVs not equipped with an odometer or an hour meter, follow the month maintenance intervals.
 For ATVs equipped with an odometer or an hour meter, follow the km (mi) or hours maintenance inter-
vals. However, keep in mind that if the ATV isn’t used for a long period of time, the month maintenance
intervals should still be followed.
 Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools,
data and technical skills. NO. ITEM CHECK OR MAINTENANCE
JOB INITIAL
EVERY
Whichev-
er comes first month136612
km (mi) 320
(200) 1300
(800) 2500
(1600) 2500
(1600) 5000
(3200)
hours 20 80 160 160 320
1 *Fuel line • Check fuel hoses for cracks or other damage, and
replace if necessary. √√√
2 Spark plug • Check condition and clean, regap, or replace if
necessary. √√√√√
3 *Va l ve s • Check valve clearance and adjust if necessary. √ √√√
4 *Carburetor • Check starter (choke) operation and correct if
necessary.
• Check engine idling speed and adjust if neces- sary. √√√√
5 *Crankcase breath-
er system • Check breather hose for cracks or other damage,
and replace if necessary. √√√
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14*Steering system • Check operation and repair or replace if dam-
aged.
• Check toe-in and adjust if necessary. √√√√√
15 *Engine mount • Check for cracks or other damage, and replace if
necessary. √√√
16 *Axle boots • Check for cracks or other damage, and replace if
necessary. √√√√√
17 Engine oil • Change.
• Check ATV for oil leakage, and correct if neces-
sary. √ √√√
18 Engine oil filter car-
tridge
• Replace.
√√√
19 Differential gear oil • Change.
• Check ATV for oil leakage, and correct if neces-
sary. √√
20 Final gear oil • Change.
• Check ATV for oil leakage, and correct if neces-
sary. √√
21 *Moving parts and
cables
• Lubricate.
√√√√
22 *Drive select lever
safety system cable • Check operation and adjust or replace if neces-
sary. √√√
NO. ITEM
CHECK OR MAINTENANCE
JOB INITIAL EVERY
Whichev-
er comes first month136612
km (mi) 320
(200) 1300
(800) 2500
(1600) 2500
(1600) 5000
(3200)
hours 20 80 160 160 320U1NS63E0.book Page 7 Monday, March 10, 2014 9:05 AM

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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.EBU2331AEngine 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 Nm (1.8 m·kgf, 13 ft·lbf)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. 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. Engine oil dipstick
2. Maximum level mark
3. Tip of the engine oil dipstick
1. Engine oil drain bolt
2. Gasket
12
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TIPSkip steps 5–7 if the oil filter cartridge is not being
replaced. 5. Remove the oil filter cartridge with an oil filterwrench.
TIPAn oil filter wrench is available at a nearby Yamaha
dealer. 6. Apply a thin coat of engine oil to the O-ring ofthe new oil filter cartridge.TIPMake sure that the O-ring is properly seated.
1. Oil filter cartridge
1
1. Oil filter wrench
1
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7. Install the new oil filter cartridge with an oil fil-
ter wrench, and then tighten it to the specified
torque with a torque wrench.
8. Install the engine oil drain bolt and its newgasket, and then tighten the bolt to the spec-
ified torque.
1. O-ring
1. Torque wrenchTightening torque:Oil filter cartridge:17 Nm (1.7 m·kgf, 12 ft·lbf)
Tightening torque: Engine oil drain bolt:23 Nm (2.3 m·kgf, 17 ft·lbf)
1
U1NS63E0.book Page 14 Monday, March 10, 2014 9:05 AM