2020 YAMAHA MT-03 remove

Periodic maintenance and adjustment
6-7
6
EAU19643
Checking the spark plugs
The spark plugs are important engine
components, which should be
checked periodically, preferably by a
Yamaha dealer. Since heat and depos-
its will cause any spark plug to slowly
erode, they should be removed and
checked in accordance with the peri-
odic maintenance and lubrication
chart. In addition, the condition of the
spark plugs can reveal the condition of
the engine.
The porcelain insulator around the
center electrode of each spark plug
should be a medium-to-light tan (the
ideal color when the vehicle is ridden
normally), and all spark plugs installed
in the engine should have the same
color. If any spark plug shows a dis-
tinctly different color, the engine could
be operating improperly. Do not at-
tempt to diagnose such problems
yourself. Instead, have a Yamaha deal-
er check the vehicle.
If a spark plug shows signs of elec-
trode erosion and excessive carbon or
other deposits, it should be replaced.
Before installing a spark plug, the
spark plug gap should be measured
with a wire thickness gauge and, if
necessary, adjusted to specification.Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the spark
plug threads.
TIP
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 as soon as possible.
Specified spark plug:
NGK/LMAR8A-9
1. Spark plug gap
Spark plug gap:
0.8–0.9 mm (0.031–0.035 in)
Tightening torque:
Spark plug:
13 N·m (1.3 kgf·m, 9.6 lb·ft)
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Periodic maintenance and adjustment
6-9
6 4. If the engine oil is below the mini-
mum level mark, add sufficient oil
of the recommended type to raise
it to the correct level.
To change the engine oil (with or
without oil filter cartridge replace-
ment)
1. Place the vehicle on a level sur-
face.
2. Start the engine, warm it up for
several minutes, and then turn it
off.
3. Place an oil pan under the engine
to collect the used oil.
4. Remove the cowling by removing
the bolts.
5. Remove the engine oil filler cap,
the engine oil drain bolt and its
gasket to drain the oil from the
crankcase.
TIP
Skip steps 6…8 if the oil filter cartridge
is not being replaced.
6. Remove the oil filter cartridge with
an oil filter wrench.
TIP
An oil filter wrench is available at a
Yamaha dealer.
7. Apply a thin coat of clean engine
oil to the O-ring of the new oil filter
cartridge.
1. Cowling
2. Bolt
22
11
1. Engine oil drain bolt
2. Gasket
1. Oil filter wrench
2. Oil filter cartridge
12
1
2
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Periodic maintenance and adjustment
6-12
6
EAU20071
Coolant
The coolant level should be checked
before each ride. In addition, the cool-
ant must be changed at the intervals
specified in the periodic maintenance
and lubrication chart.
EAU38176To check the coolant level
1. Place the vehicle on a level sur-
face and hold it in an upright posi-
tion.
TIP
The coolant level must be
checked on a cold engine since
the level varies with engine tem-
perature.
Make sure that the vehicle is posi-
tioned straight up when checking
the coolant level. A slight tilt to the
side can result in a false reading.
2. Check the coolant level in the
coolant reservoir.
TIP
The coolant should be between the
minimum and maximum level marks.
3. If the coolant is at or below the
minimum level mark, remove the
coolant reservoir cover by remov-
ing the bolts, remove the coolant
reservoir cap, and then add cool-
ant to the maximum level mark.
WARNING! Remove only the
coolant reservoir cap. Never at-
tempt to remove the radiator
cap when the engine is hot.
[EWA15162] NOTICE: If coolant is not
available, use distilled water or
soft tap water instead. Do not
use hard water or salt water
since it is harmful to the engine.
If water has been used instead
of coolant, replace it with cool-
ant as soon as possible, other-
wise 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 anti-
freeze content of the coolant as
soon as possible, otherwise the
effectiveness of the coolant will
be reduced.
[ECA10473]
1. Maximum level mark
2. Minimum level mark
3. Coolant reservoir
1
2
3
1. Bolt
2. Coolant reservoir cover
2
1
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Periodic maintenance and adjustment
6-13
6 4. Install the reservoir cap, and then
install the coolant reservoir cover
by installing the bolts.EAU33032Changing the coolant
The coolant must be changed at the in-
tervals specified in the periodic mainte-
nance and lubrication chart. Have a
Yamaha dealer change the coolant.
WARNING! Never attempt to remove
the radiator cap when the engine is
hot.
[EWA10382]EAUN1172
Replacing the air filter ele-
ment and cleaning the check
hose
The air filter element should be re-
placed at the intervals specified in the
periodic maintenance and lubrication
chart. Replace the air filter element
more frequently if you are riding in un-
usually wet or dusty areas. In addition,
the air filter check hose must be fre-
quently checked and cleaned if neces-
sary.
To replace the air filter element
1. Remove the rider seat. (See page
3-17.)
2. Remove the left side panel bolts.
3. Remove the left side panel by re-
moving the lower projection on the
panel from the slot, and then re-
moving the upper projection as
shown.
1. Coolant reservoir cap
Coolant reservoir capacity (up to
the maximum level mark):
0.25 L (0.26 US qt, 0.22 Imp.qt)
1
1. Left side panel
2. Bolt
2 1
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Periodic maintenance and adjustment
6-14
64. Lift up the rubber covers, and then
remove the air filter case cover by
removing the screws.
5. Pull the air filter element out.
6. Insert a new air filter element into
the air filter case. NOTICE: Make
sure that the air filter element is
properly seated in the air filtercase. The engine should never
be operated without the air filter
element installed, otherwise the
piston(s) and/or cylinder(s) may
become excessively worn.
[ECA10482]
7. Install the air filter case cover by
installing the screws, and then
place the rubber covers in their
original positions.
8. Place the left side panel in the
original position, and then install
the bolts.
9. Install the rider seat.
To clean the air filter check hose
1. Check the hose on the front of the
air filter case for accumulated dirt
or water.
2. If dirt or water is visible, remove
the hose, clean it, and then install
it.
1. Projection
1. Air filter case cover
2. Screw
3. Rubber cover
1. Air filter element
1
12
23
1
1. Air filter check hose
1
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Periodic maintenance and adjustment
6-23
6
EAU22762
Drive chain slack
The drive chain slack should be
checked before each ride and adjusted
if necessary.
EAU74253To check the drive chain slack
1. Place the motorcycle on the side-
stand.
TIP
When checking and adjusting the drive
chain slack, there should be no weight
on the motorcycle.
2. Shift the transmission into the
neutral position.
3. Measure the drive chain slack as
shown.
4. If the drive chain slack is incorrect,
adjust it as follows. NOTICE: Im-
proper drive chain slack will
overload the engine as well as
other vital parts of the motorcy-
cle and can lead to chain slip-
page or breakage. To prevent
this from occurring, keep the
drive chain slack within the
specified limits.
[ECA10572]EAU62983
To adjust the drive chain slack
Consult a Yamaha dealer before ad-
justing the drive chain slack.
1. Remove the drive chain puller cap,
and then loosen the axle nut and
the locknut on each side of the
swingarm.
2. To tighten the drive chain, turn the
drive chain slack adjusting nut on
each side of the swingarm in di-
rection (a). To loosen the drive
chain, turn the adjusting nut on
each side of the swingarm in di-
rection (b), and then push the rear
wheel forward.
1. Drive chain slack
Drive chain slack:
35.0–45.0 mm (1.38–1.77 in)
1
1. Axle nut
2. Locknut
3. Drive chain puller cap
1. Drive chain slack adjusting nut
2
3
1
1(a)
(b)
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Periodic maintenance and adjustment
6-30
6Batteries produce explosive hy-
drogen gas. Therefore, keep
sparks, flames, cigarettes, etc.,
away from the battery and pro-
vide sufficient ventilation when
charging it in an enclosed
space.
KEEP THIS AND ALL BATTER-
IES OUT OF THE REACH OF
CHILDREN.
NOTICE
ECA10621
Never attempt to remove the battery
cell seals, as this would permanently
damage the battery.
To charge the battery
Have your Yamaha dealer charge the
battery if it seems to have discharged.
Keep in mind that the battery tends to
discharge more quickly if the vehicle is
equipped with optional electrical ac-
cessories.
NOTICE
ECA16522
To charge a VRLA (Valve Regulated
Lead Acid) battery, a special (con-
stant-voltage) battery charger is re-
quired. Using a conventional battery
charger will damage the battery.
To store the battery
1. If the vehicle will not be used for
more than one month, remove the
battery, fully charge it, and then
place it in a cool, dry place.
NOTICE: When removing the
battery, be sure to turn the main
switch off, then disconnect the
negative lead before discon-
necting the positive lead.
[ECA16304]
2. If the battery will be stored for
more than two months, check it at
least once a month and fully
charge it if necessary.
3. Fully charge the battery before in-
stallation. NOTICE: When install-
ing the battery, be sure to turn
the main switch off, then con-
nect the positive lead before
connecting the negative lead.
[ECA16842]
4. After installation, make sure that
the battery leads are properly con-
nected to the battery terminals.
NOTICE
ECA16531
Always keep the battery charged.
Storing a discharged battery can
cause permanent battery damage.
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Periodic maintenance and adjustment
6-31
6
EAU62776
Replacing the fuses
The main fuse is located under the
passenger seat. The fuse box, which
contains the fuses for the individual cir-
cuits, is located behind the center pan-
el.
To access the main fuse, proceed as
follows.
1. Remove the passenger seat. (See
page 3-17.)
2. Remove the tray by removing the
quick fasteners.
3. Pull back the starter relay cover.
4. Disconnect the starter relay cou-
pler by pressing from both sides.5. Connect the starter relay coupler,
and then slide the cover to its orig-
inal position.
6. Place the tray in its original posi-
tion, and then install the quick fas-
teners.
7. Install the passenger seat.
TIP
To access the fuse box, remove the
center cover. (See page 3-17.)
1. Quick fastener
2. Tray
1. Starter relay cover
2. Starter relay coupler
3. Main fuse
4. Spare main fuse
2
1
1
2
3
4
1. Fuse box
1. Ignition fuse
2. Signaling system fuse
3. ABS control unit fuse
4. Headlight fuse
5. Backup fuse (for clock)
6. Radiator fan motor fuse
7. Spare fuse
1
71
2
3
5
6
4
UB6WE0E0.book Page 31 Friday, March 27, 2020 11:37 AM