2018 YAMAHA AEROX50 engine

Periodic maintenance and adjustment
6-10
6
4. Clean the oil strainer with solvent,
and then check it for damage and
replace it if necessary.
5. Check the O-ring for damage and
replace it if necessary.
6. Install the oil strainer, compres-
sion spring, O-ring and engine oil
drain bolt B.
TIPMake sure that the O-ring is properly
seated.7. Install engine oil drain bolt A, and
then tighten both drain bolts to
their specified torques.8. Refill with the specified amount of
the recommended engine oil, and
then install and tighten the oil filler
cap.
NOTICE
ECA11671
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 CONSERVING II” or
higher.
Be sure no foreign material en-
ters the crankcase.
9. 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.
10. Turn the engine off, and then
check the oil level and correct it if
necessary.
To reset the oil change indicatorTIPThe oil change indicator can only be re-
set when “OIL CHANGE” appears in
the multi-function display.1. While the key is turned to “ ”,
hold the button pushed more than
eight seconds.
1. Engine oil drain bolt B
2. Strainer
3. Compression spring
4. O-ring
Tightening torque:
Engine oil drain bolt A:
23 N·m (2.3 kgf·m, 17 lb·ft)
Engine oil drain bolt B:
32 N·m (3.2 kgf·m, 24 lb·ft)
Recommended engine oil:
See page 8-1.
Oil change quantity:
0.78 L (0.82 US qt, 0.69 Imp.qt)
1. Oil filler hole
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Periodic maintenance and adjustment
6-11
62. Release the button, and the oil
change indicator will go off.
EAUT1563
Final transmission oilThe final transmission case must be
checked for oil leakage before each
ride. If any leakage is found, have a
Yamaha dealer check and repair the
scooter. In addition, the final transmis-
sion oil must be changed as follows at
the intervals specified in the periodic
maintenance and lubrication chart.
1. Start the engine, warm it up by rid-
ing the scooter for several min-
utes, and then stop the engine.
2. Place the scooter on the center-
stand.
3. Place an oil pan under the final
transmission case to collect the
used oil.
4. Remove the oil filler bolt and drain
bolt to drain the oil from the final
transmission case.5. Install the final transmission oil
drain bolt, and then tighten it to
the specified torque.
6. Refill with the specified amount of
the recommended final transmis-
sion oil, and then install the oil filler
bolt and tighten it to the specified
torque. WARNING! Make sure
that no foreign material enters
the final transmission case.
Make sure that no oil gets on
the tire or wheel.
[EWA11312]
1. Final transmission oil filler bolt
2. Final transmission oil drain boltTightening torque:
Final transmission oil drain bolt:
13 N·m (1.3 kgf·m, 9.6 lb·ft)ZAUM1073
2
1
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Periodic maintenance and adjustment
6-12
6 7. Check the final transmission case
for oil leakage. If oil is leaking,
check for the cause.
EAU20071
CoolantThe 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.
EAUM3182
To 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 through
the check window.TIPThe coolant should be between the
minimum and maximum level marks.
3. If the coolant is at or below the
minimum level mark, remove the
panel A. (See page 6-6.)
4. Open the reservoir cap, and then
add coolant to the maximum level
mark. WARNING! Remove only
the coolant reservoir cap. Never
attempt 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-
Tightening torque:
Final transmission oil filler bolt:
23 N·m (2.3 kgf·m, 17 lb·ft)
Recommended final transmission
oil:
See page 8-1.
Oil quantity:
0.10 L (0.11 US qt, 0.09 Imp.qt)
1. Maximum level mark
2. Minimum level markZAUM1074
1
2
FULLFULLLOWLOW
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Periodic maintenance and adjustment
6-13
6wise 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]
5. Close the reservoir cap, and then
install the panel.
EAU33032
Changing the coolant
The coolant must be changed at the in-
tervals specified in the periodic main-
tenance and lubrication chart. Have a
Yamaha dealer change the coolant.
WARNING! Never attempt to remove
the radiator cap when the engine is
hot.
[EWA10382]EAUT1492
Replacing the air filter ele-
ment and cleaning the check
hoseThe 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.
1. Coolant reservoir capCoolant reservoir capacity:
0.26 L (0.27 US qt, 0.23 Imp.qt)ZAUM1075
1
1. Air filter case cover
2. Air filter element
3. Air filter check hoseZAUM1555
1
2
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Periodic maintenance and adjustment
6-14
6 To replace the air filter element
1. Remove the air filter case cover by
removing the screws.
2. Pull the air filter element out.
3. Insert a new air filter element into
the air filter case as shown.
NOTICE: Make sure that the air
filter element is properly seated
in the air filter case. The engine
should never be operated with-
out the air filter element in-
stalled, otherwise the piston(s)
and/or cylinder(s) may become
excessively worn.
[ECA10482]
4. Install the air filter case cover by
installing the screws.
To clean the air filter check hose
1. Check the hose on the side 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.
EAU21386
Checking the throttle grip free
playMeasure 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 clearanceThe 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.TIPThis 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)1ZAUM0051
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Periodic maintenance and adjustment
6-29
6
EAUM3290
Troubleshooting chartsStarting problems or poor engine performance
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.
There is no fuel.
Check the battery.
Supply fuel.
The engine does not start.
Check the battery.
4. Compression
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.
Remove the spark plug
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug.
Have a Yamaha dealer check the vehicle.
The engine does not start.
Check the compression.
Operate the electric starter.2. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.
DryWet
The engine does not start.
Check the ignition.
Operate the electric
starter or the kickstarter.
Check the electrolyte and battery
lead connections, and charge the
battery if necessary.
Operate the electric starter or the
kickstarter.
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Periodic maintenance and adjustment
6-30
6 Engine overheating
WARNING
EWAT1041
Do not remove the radiator cap when the engine and radiator are hot. Scalding hot fluid and steam may be
blown out under pressure, which could cause serious injury. Be sure to wait until the engine has cooled.
Place a thick rag, like a towel, over the radiator cap, and then slowly rotate the cap counterclockwise to the
detent to allow any residual pressure to escape. When the hissing sound has stopped, press down on the cap
while turning it counterclockwise, and then remove the cap.TIPIf coolant is not available, tap water can be temporarily used instead, provided that it is changed to the recommended cool-
ant as soon as possible.
Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer checkand repair the cooling system.Add coolant. (See TIP.)
Start the engine. If the engine overheats again,
have a
Yamaha dealer check
and repair the cooling system.
There is
leakage.
There is
no leakage.
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Scooter care and storage
7-1
7
EAU37834
Matte color cautionNOTICE
ECA15193
Some models are equipped with
matte colored finished parts. Be
sure to consult a Yamaha dealer for
advice on what products to use be-
fore cleaning the vehicle. Using a
brush, harsh chemical products or
cleaning compounds when cleaning
these parts will scratch or damage
their surface. Wax also should not
be applied to any matte colored fin-
ished parts.
EAU26096
CareWhile the open design of a scooter re-
veals the attractiveness of the technol-
ogy, it also makes it more vulnerable.
Rust and corrosion can develop even if
high-quality components are used. A
rusty exhaust pipe may go unnoticed
on a car, however, it detracts from the
overall appearance of a scooter. Fre-
quent and proper care does not only
comply with the terms of the warranty,
but it will also keep your scooter look-
ing good, extend its life and optimize
its performance.
Before cleaning
1. Cover the muffler outlet with a
plastic bag after the engine has
cooled down.
2. Make sure that all caps and cov-
ers as well as all electrical cou-
plers and connectors, including
the spark plug cap, are tightly in-
stalled.
3. Remove extremely stubborn dirt,
like oil burnt onto the crankcase,
with a degreasing agent and a
brush, but never apply such prod-ucts onto seals, gaskets and
wheel axles. Always rinse the dirt
and degreaser off with water.
Cleaning
NOTICE
ECA10784
Avoid using strong acidic wheel
cleaners, especially on spoked
wheels. If such products are
used on hard-to-remove dirt, do
not leave the cleaner on the af-
fected area any longer than in-
structed. Also, thoroughly rinse
the area off with water, immedi-
ately dry it, and then apply a cor-
rosion protection spray.
Improper cleaning can damage
plastic parts (such as cowlings,
panels, windshields, headlight
lenses, meter lenses, etc.) and
the mufflers. Use only a soft,
clean cloth or sponge with wa-
ter to clean plastic. However, if
the plastic parts cannot be thor-
oughly cleaned with water, di-
luted mild detergent with water
may be used. Be sure to rinse
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