2008 YAMAHA YFM350R check engine

6-6
6 erly lubricated only when the engine is run-
ning. Inadequate lubrication may damage
the transmission.

Always use the clutch when changing gears.
The engine, transmission and drive train are
not designed to withstand the shock of
forced shifting and can be damaged by shift-ing without using the clutch.EBU20672Engine break-in NOTE:
For ATVs equipped with an odometer or an hour
meter, follow the figures given in km (mi) or the
figures given in hours.
For ATVs not equipped with an odometer orhour meter, follow the figures given in hours.
There is never a more important period in the life of
your engine than the first 320 km (200 mi) or 20
hours of riding. For this reason, you should read
the following material carefully.
Since the engine is brand new, do not put an ex-
cessive load on it for the first 320 km (200 mi) or 20
hours. The various parts in the engine wear and
polish themselves to the correct operating clear-ances. During this period, prolonged full-throttle
operation or any condition that might result in en-
gine overheating must be avoided.
0–160 km (0–100 mi) or 0–10 hours
Avoid prolonged operation above 1/2 throttle. Vary
the speed of the ATV regularly. Do not operate it at
one set throttle position.
160–320 km (100–200 mi) or 10–20 hours
Avoid prolonged operation above 3/4 throttle. Rev
the engine through the gears freely, but do not use
full throttle at any time.
320 km (200 mi) or 20 hours and beyond
The ATV can now be operated normally.
CAUTION:ECB00220If any engine trouble should occur during the
engine break-in period, immediately have aYamaha dealer check the ATV.EBU20721Parking When parking the ATV, stop the engine, shift into
first gear, apply the parking brake, and then turn
the fuel cock to “OFF”.
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8-3
8
EBU21742Periodic maintenance chart for the emission control system NOTE:
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 be followed.
Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools,data and technical skills.NO. ITEMCHECK OR MAINTENANCE
JOBINITIAL EVERY
Whichev-
er comes
firstmonth136612
km
(mi)320
(200)1300
(800)2500
(1600)2500
(1600)5000
(3200)
hours 20 80 160 160 320
1*Fuel lineCheck fuel hoses for cracks or other damage, and
replace if necessary.√√√
2 Spark plugCheck condition and clean, regap, or replace if
necessary.√√√√√
3*ValvesCheck valve clearance and adjust if necessary.√ √√√
4*CarburetorCheck starter (choke) operation and correct if nec-
essary.
Check engine idling speed and adjust if neces-
sary.√√√√
5*Crankcase breather
systemCheck breather hose for cracks or other damage,
and replace if necessary.√√√
U5YT64E0.book Page 3 Monday, April 9, 2007 1:03 PM

8-6
8
10*Swingarm pivotsCheck operation and for excessive play, and re-
place bearings if necessary.
Lubricate with lithium-soap-based grease.√√√
11*Upper and lower
arm pivotsLubricate with lithium-soap-based grease.√√√
12 Drive chainCheck chain slack and adjust if necessary.
Check rear wheel alignment and correct if necess-
sary.
Clean and lubricate.√√√√√
13*Drive chain rollersCheck for wear and replace if necessary.√√√
14*Chassis fastenersMake sure that all nuts, bolts, and screws are
properly tightened.√√√√√
15*Shock absorber as-
sembliesCheck operation and correct if necessary.
Check for oil leakage and replace if necessary.√√√
16*Rear suspension re-
lay arm and con-
necting arm
pivoting pointsCheck operation and correct if necessary.
Lubricate with lithium-soap-based grease.√√√√
17*Steering shaftLubricate with lithium-soap-based grease.√√√
18*Steering systemCheck operation and repair or replace if damaged.
Check toe-in and adjust if necessary.√√√√√
19 Engine oilChange.
Check ATV for oil leakage, and correct if neces-
sary.√ √√√ NO. ITEMCHECK OR MAINTENANCE
JOBINITIAL EVERY
Whichev-
er comes
firstmonth136612
km
(mi)320
(200)1300
(800)2500
(1600)2500
(1600)5000
(3200)
hours 20 80 160 160 320U5YT64E0.book Page 6 Monday, April 9, 2007 1:03 PM

8-7
8
EBU23070NOTE:
The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
Hydraulic brake service
Regularly check and, if necessary, correct the brake fluid level.
Every two years replace the internal components of the brake master cylinders and calipers, and
change the brake fluid.20Engine oil filter ele-
mentClean or replace if necessary.√√√
21 Engine oil strainerClean.√√√
22*Moving parts and
cablesLubricate.√√√√
23*Throttle lever hous-
ing and cableCheck operation and correct if necessary.
Check throttle cable free play and adjust if neces-
sary.
Lubricate throttle lever housing and cable.√√√√√
24*Front and rear brake
switchesCheck operation and correct if necessary.√√√√√
25*Lights and switchesCheck operation and correct if necessary.
Adjust headlight beams.√√√√√ NO. ITEMCHECK OR MAINTENANCE
JOBINITIAL EVERY
Whichev-
er comes
firstmonth136612
km
(mi)320
(200)1300
(800)2500
(1600)2500
(1600)5000
(3200)
hours 20 80 160 160 320U5YT64E0.book Page 7 Monday, April 9, 2007 1:03 PM

8-9
8
EBU23211Checking the spark plug The 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 accor-
dance with the periodic maintenance and lubrica-
tion chart. In addition, the condition of the spark
plug can reveal the condition of the engine.
To remove the spark plug
1. 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).
NOTE:If 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.
1. Spark plug cap
1. Spark plug wrench
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8
NOTE:If 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 assoon as possible.
4. Install the spark plug cap.EBU23277Engine 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.NOTE:If 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 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.
NOTE:The engine oil should be between the minimumand maximum level marks.1. Dipstick
2. Maximum level mark
3. Minimum level mark
4. Engine oil filler cap
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8-13
8 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 it if
necessary.
8. Install the oil filter element and O-ring.
NOTE:Make 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.
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.
CAUTION:ECB00320Before installing the engine oil drain bolt, be
sure to install the O-ring, compression springand oil strainer.
11. Add the specified amount of the recommend-
ed engine oil, and then install and tighten the
engine oil filler cap.
1. Oil filter element cover
2. Bolt
3. Oil filter element
4. O-ring
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)
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8-14
8
NOTE:Be sure to wipe off spilled oil on any parts after theengine and exhaust system have cooled down.CAUTION:ECB00300
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 thecrankcase.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.
EBU23741Cleaning the air filter element The air filter element should be cleaned at the in-
tervals specified in the periodic maintenance and
lubrication chart. Clean the air filter element more
frequently if you are riding in unusually wet or dusty
areas.NOTE:There 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. 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)
U5YT64E0.book Page 14 Monday, April 9, 2007 1:03 PM