2010 YAMAHA YFM350R Owners Manual

8-10
8
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 erosion
and 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 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. 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
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.3. Install the spark plug cap.EBU2327CEngine 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 cleaned at the intervals speci-
fied in the periodic maintenance and lubrication
chart.
To check the engine oil level
1. 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.TIPThe engine oil should be between the minimum
and maximum level marks.
Tightening torque:
Spark plug:
17.5 Nm (1.75 m·kgf, 12.7 ft·lbf)
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5. If the engine oil is at or below the minimum
level 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.
[ECB00851]
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 element cleaning)
1. Place the ATV on a level surface.
2. Start the engine, warm it up for several min-
utes, 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 to drain the oil
from the crankcase. NOTICE: When remov-
ing the engine oil drain bolt, the compres-
sion spring, oil strainer and O-ring will fall
out. Take care not to lose these parts.
[ECB00311]
1. Engine oil dipstick
2. Maximum level mark
3. Minimum level mark
4. Engine oil filler capU1BS60E0.book Page 12 Thursday, April 16, 2009 4:11 PM

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TIPSkip steps 5–9 if the oil filter element is not being
cleaned.5. Remove the oil filter element cover by remov-
ing the bolts, and then remove the oil filter el-
ement.6. Clean the oil strainer and oil filter element with
solvent.
7. Check the O-rings for damage and replace
them if necessary.
8. Install the oil filter element and O-ring.
TIPMake sure that the O-ring is properly seated.9. Install the oil filter element cover by installing
the bolts, and then tighten them to the speci-
fied torque.
1. Engine oil drain bolt
2. O-ring
3. Compression spring
4. Oil strainer
1. Oil filter element cover
2. Bolt
3. Oil filter element
4. O-ring
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8 10. Install the oil strainer, compression spring, O-
ring and engine oil drain bolt. Tighten the en-
gine oil drain bolt to the specified torque.
NOTICE: Before installing the engine oil
drain bolt, be sure to install the O-ring,
compression spring and oil strainer.
[ECB00321]
11. Refill with the specified amount of the recom-
mended engine oil, and then install and tight-
en the engine oil filler cap.
TIPBe sure to wipe off spilled oil on any parts after the
engine and exhaust system have cooled down.NOTICEECB00300
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.
Tightening torque:
Oil filter element cover bolt:
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Tightening torque:
Engine oil drain bolt:
32 Nm (3.2 m·kgf, 23 ft·lbf)
Recommended oil:
See page 10-1.
Oil quantity:
Without oil filter element replacement:
2.50 L (2.64 US qt, 2.20 Imp.qt)
With oil filter element replacement:
2.60 L (2.75 US qt, 2.29 Imp.qt)
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812. 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.
EBU23743Cleaning the air filter element The 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
riding 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 4-12.)
3. Remove the air filter case cover by unhooking
the holders.1. Air filter case check hose
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8 4. Pull the air filter element out of the air filter
case.5. Remove the sponge material from the air filter
element frame.
1. Air filter case cover
2. Air filter case cover holder
1. Air filter element assembly
1. Unlock.
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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.
[EWB01941]
7. Squeeze the excess solvent out of the sponge
material and let it dry. NOTICE: Do not twist
the sponge material when squeezing it.
[ECB00441]
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.
11. Apply all-purpose grease to the air filter ele-
ment seat.
12. 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.
1. Air filter element retaining plate
2. Air filter element frame
3. Sponge material
4. Air filter element seatU1BS60E0.book Page 17 Thursday, April 16, 2009 4:11 PM