2020 YAMAHA MT-03 check engine

Periodic maintenance and adjustment
6-11
6 addition, do not use oils labeled
“ENERGY CONSERVING II” or
higher.
Make sure that no foreign mate-
rial enters the crankcase.
11. Install the cowling by installing the
bolts.
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.
TIP
After the engine is started, the engine
oil pressure warning light should go off.
NOTICE
ECA20860
If the oil pressure warning light flick-
ers or remains on even if the oil level
is correct, immediately turn the en-
gine off and have a Yamaha dealer
check the vehicle.
13. Turn the engine off, wait a few
minutes until the oil settles, and
then check the oil level and cor-
rect it if necessary.
EAU85450
Why Yamalube
YAMALUBE oil is a Genuine YAMAHA
Part born of the engineers’ passion
and belief that engine oil is an impor-
tant liquid engine component. We form
teams of specialists in the fields of me-
chanical engineering, chemistry, elec-
tronics and track testing, and have
them develop the engine together with
the oil it will use. Yamalube oils take full
advantage of the base oil’s qualities
and blend in the ideal balance of addi-
tives to make sure the final oil clears
our performance standards. Thus,
Yamalube mineral, semisynthetic and
synthetic oils have their own distinct
characters and value. Yamaha’s expe-
rience gained over many years of re-
search and development into oil since
the 1960’s helps make Yamalube the
best choice for your Yamaha engine.
UB6WE0E0.book Page 11 Friday, March 27, 2020 11:37 AM

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
UB6WE0E0.book Page 12 Friday, March 27, 2020 11:37 AM

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
UB6WE0E0.book Page 13 Friday, March 27, 2020 11:37 AM

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
UB6WE0E0.book Page 14 Friday, March 27, 2020 11:37 AM

Periodic maintenance and adjustment
6-15
6
EAU21386
Checking the throttle grip free
play
Measure the throttle grip free play as
shown.
Periodically check the throttle grip free
play and, if necessary, have a Yamaha
dealer adjust it.
EAU21403
Valve clearance
The valves are an important engine
component, and since valve clearance
changes with use, they must be
checked and adjusted at the intervals
specified in the periodic maintenance
chart. Unadjusted valves can result in
improper air-fuel mixture, engine
noise, and eventually engine damage.
To prevent this from occurring, have
your Yamaha dealer check and adjust
the valve clearance at regular intervals.
TIP
This service must be performed when
the engine is cold.1. Throttle grip free play
Throttle grip free play:
3.0–5.0 mm (0.12–0.20 in)
1
UB6WE0E0.book Page 15 Friday, March 27, 2020 11:37 AM

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)
UB6WE0E0.book Page 23 Friday, March 27, 2020 11:37 AM

Periodic maintenance and adjustment
6-34
65. Insert a new bulb into the socket.
6. Install the socket (together with
the bulb) by pushing it in.
7. Install the rear fender lower panel
by installing the bolts and screws.
8. Install the mudguard by installing
the quick fasteners.
EAU24351
Supporting the motorcycle
Since this model is not equipped with a
centerstand, follow these precautions
when removing the front and rear
wheel or performing other mainte-
nance requiring the motorcycle to
stand upright. Check that the motorcy-
cle is in a stable and level position be-
fore starting any maintenance. A
strong wooden box can be placed un-
der the engine for added stability.
To service the front wheel
1. Stabilize the rear of the motorcy-
cle by using a motorcycle stand
or, if an additional motorcycle
stand is not available, by placing a
jack under the frame in front of the
rear wheel.
2. Raise the front wheel off the
ground by using a motorcycle
stand.
To service the rear wheel
Raise the rear wheel off the ground by
using a motorcycle stand or, if a motor-
cycle stand is not available, by placing
a jack either under each side of the
frame in front of the rear wheel or under
each side of the swingarm.
1. License plate light bulb
2. License plate light bulb socket
2
1
UB6WE0E0.book Page 34 Friday, March 27, 2020 11:37 AM

Periodic maintenance and adjustment
6-36
6
EAU86390
Troubleshooting chart
1. FuelThere is enough fuel.
There is no fuel.
Check the battery.
Supply fuel.
The engine turns over
quickly.
The engine turns over
slowly.
Try starting the
engine.
The engine does not
start.
Check the battery.
Wipe off with a dry
cloth and correct the
spark plug gap, or
replace the spark
plug(s).
Check the battery
lead connections,
and charge the
battery if necessary.
2. BatteryThe battery is good.
The engine does not
start.
Check the ignition.
3. IgnitionWet
Dry
There is compression.
There is no
compression.
The engine does not start.
Have a Yamaha dealer check the vehicle.
Have a Yamaha dealer check the vehicle.
The engine does not
start.
Check the
compression.Have a Yamaha
dealer check the
vehicle.
Remove the spark
plug and check
the electrodes.
Operate the electric
starter.
Try starting the
engine.
Check the fuel level
in the fuel tank.
4. Compression
UB6WE0E0.book Page 36 Friday, March 27, 2020 11:37 AM