2018 SUBARU WRX engine

(513,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
CAUTION
.For models except STI, be careful
not to touch the engine oil filter
when removing the oil filler cap.
Doing so may result in a burn, a
pinched finger, or may cause
some other injury.
.Use only engine oil with the
recommended grade and vis-
cosity.
.Be careful not to spill engine oil
when adding it. If oil touches the
exhaust pipe, it may cause a bad
smell, smoke, and/or a fire. If
engine oil gets on the exhaust
pipe, be sure to wipe it off.
To add engine oil, remove the engine oil
filler cap and slowly pour engine oil
through the filler neck. After pouring oil
into the engine, you must use the level
gauge to confirm that the oil level is
correct.
For models STI, just after driving or while
the engine is warm, the engine oil level
reading may be in a range between the
upper level and the notch mark. This is
caused by thermal expansion of the
engine oil.
NOTETo prevent overfilling the engine oil, do
not add any additional oil above the
upper level when the engine is cold.&Changing the oil and oil filterChange the oil and oil filter according to
the maintenance schedule in the“War-
ranty and Maintenance Booklet”.
The engine oil and oil filter must be
changed more frequently than listed in
the maintenance schedule when driving
on dusty roads, when short trips are
frequently made, or when driving in ex-
tremely cold weather.NOTE.Changing the engine oil and oil filter
should be performed by a well-trained
expert. Contact your SUBARU dealer
for changing the engine oil and oil filter.
Fully trained mechanics are on standby
at a SUBARU dealer to utilize the
special tools, spare parts and recom-
mended oil for this work, and also, used
oils are properly disposed of.
.If performing oil replacement your-
self, observe the local regulations and
dispose of waste oil properly.
&Recommended grade and
viscosity
CAUTION
Use only engine oil with the recom-
mended grade and viscosity.
Refer to“Engine oil”F12-4.NOTEEngine oil viscosity (thickness) affects
fuel economy. Oils of lower viscosity
provide better fuel economy. However,
in hot weather, oil of higher viscosity is
required to properly lubricate the en-
gine.
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Maintenance and service/Engine oil
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(514,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
&Synthetic oilYou must follow the oil and filter changing
intervals shown in the Warranty and
Maintenance booklet.NOTESynthetic oil of the grade and viscosity
noted in chapter 12 is the recom-
mended engine oil for optimum engine
performance. Conventional oil may be
used if synthetic oil is unavailable.
Cooling system
WARNING
.Never attempt to remove the
radiator cap until the engine has
been shut off and has cooled
down completely. Since the cool-
ant is under pressure, you may
suffer serious burns from a spray
of boiling hot coolant when the
cap is removed.
.Be careful of the rotating cooling
fan when the engine hood is
open. When the engine tempera-
ture is high, the cooling fan in the
engine compartment may oper-
ate when the ignition switch is in
the“ON”position, even if the
engine is stopped. Touching the
cooling fan while it is rotating
may result in injury.
CAUTION
.Vehicles are filled at the factory
with SUBARU Super Coolant that
does not require the first change
for 11 years/137,500 miles (11
years/220,000 km). Do not mix
this coolant with any other brandor type of coolant during this
period. Mixing with a different
coolant will reduce the life of the
coolant. Should it be necessary
to top up the coolant for any
reason, use only SUBARU Super
Coolant.
If the SUBARU Super Coolant is
diluted with another brand or
type, the maintenance interval is
shortened to that of the mixing
coolant.
.Do not splash the engine coolant
over painted parts. The alcohol
contained in the engine coolant
may damage the paint surface.
Maintenance and service/Cooling system
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(515,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
&Cooling fan, hose and con-
nectionsYour vehicle employs an electric cooling
fan which is thermostatically controlled to
operate when the engine coolant reaches
a specific temperature.Temperature gauge
1) Normal operating rangeIf the radiator cooling fan does not operate
even when the engine coolant tempera-
ture gauge exceeds the normal operating
range, the cooling fan circuit may be
defective. Refer to“Temperature gauge”
F3-11.
Check the fuse and replace it if necessary.
Refer to“Fuses”F11-42 and“Fuses and
circuits”F12-10.
If the fuse is not blown, have the coolingsystem checked by your SUBARU dealer.
If frequent addition of coolant is necessary,
there may be a leak in the engine cooling
system. It is recommended that the cooling
system and connections be checked for
leaks, damage, or looseness.
&Engine coolant!Checking the coolant level1)“FULL”level mark
2)“LOW”level markCheck the coolant level at each fuel stop.
1. Check the coolant level on the outside
of the reservoir while the engine is cool.
2. If the level is close to or lower than the
“LOW”level mark, add coolant up to the
“FULL”level mark. If the reserve tank isempty, remove the radiator cap and refill
coolant up to just below the filler neck as
shown in the following illustration.
STI
1) Fill up to this level
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Maintenance and service/Cooling system
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(516,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
Except STI
1) Fill up to this level3. After refilling the reserve tank and the
radiator, reinstall the cap and check that
the rubber gaskets inside the radiator cap
are in the proper position.
CAUTION
.Be careful not to spill engine
coolant when adding it. If coolant
touches the exhaust pipe, it may
cause a bad smell, smoke, and/or
a fire. If engine coolant gets on
the exhaust pipe, be sure to wipe
it off.
.Do not splash the engine coolant
over painted parts. The alcohol
contained in the engine coolant
may damage the paint surface.
!Changing the coolant
It may be difficult to change the coolant.
Have the coolant changed by your
SUBARU dealer if necessary.
Have the coolant changed according to the
maintenance schedule in the“Warranty
and Maintenance Booklet”.
Air cleaner element
WARNING
Do not operate the engine with the
air cleaner element removed. The air
cleaner element not only filters in-
take air but also stops flames if the
engine backfires. If the air cleaner
element is not installed when the
engine backfires, you could be
burned.
CAUTION
When replacing the air cleaner ele-
ment, use a genuine SUBARU air
cleaner element. If it is not used,
there is the possibility of causing a
negative effect to the engine.
The air cleaner element functions as a filter
screen. When the element is perforated or
removed, engine wear will be excessive
and engine life shortened.
It is not necessary to clean or wash the air
cleaner element.
Maintenance and service/Air cleaner element
11-18

(519,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
Spark plugsIt may be difficult to replace the spark
plugs. It is recommended that you have the
spark plugs replaced by your SUBARU
dealer.
Have the spark plugs replaced according
to the maintenance schedule in the“War-
ranty and Maintenance Booklet”.&Recommended spark plugsFor the recommended spark plugs, refer to
“Electrical system”F12-8.
Drive beltsNOTEFor models except STI, it is unneces-
sary to check the deflection of the drive
belt periodically because this engine is
equipped with an automatic belt ten-
sion adjuster. However, have the belt
replaced according to the maintenance
schedule in the“Warranty and Main-
tenance Booklet”. Consult your
SUBARU dealer for replacement.
If the drive belt is loose, cracked or
worn, contact your SUBARU dealer.
STI
1) Power steering oil pump pulley
2) Front side belt
3) Alternator pulley
4) Air conditioner compressor pulley
5) Rear side belt
6) Crank pulley
A) 22 lbf (98 N, 10 kgf)
CAUTION
The front side belt, which runs in
conjunction with the following com-
ponents, must be used within the
specified deflection.
.Power steering oil pump pulley
.Alternator pulley
.Crank pulley
Check the deflection of the front side
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Maintenance and service/Spark plugs
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(520,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
belt and if there is any looseness,
cracks, wear or unusual noise on the
front side belt, contact your
SUBARU dealer.
Continuing to use the vehicle with
the belt outside of the specification
may cause the engine to malfunc-
tion and the above components to
malfunction.
To check the deflection of the front side
belt, place a straightedge (ruler) across
two adjacent pulleys (alternator pulley and
crank pulley) and apply a force of 22 lbf (98
N, 10 kgf) midway between the pulleys by
using a spring scale. The belt deflection
should be the amount specified. If the front
side belt is loose, cracked or worn, contact
your SUBARU dealer.
in (mm)
Deflection
New belt
Used belt
A0.28–0.35
(7.0–9.0)0.35–0.43
(9.0–11.0)
The rear side belt is a stretch-type belt,
therefore the deflection does not need to
be checked. If there are cracks or wear
confirmed on the belts and a squeaking
noise is heard from them, contact your
SUBARU dealer.
Manual transmission oilIt is not necessary to check the transmis-
sion oil level. Check that there are no
cracks, damage or leakage. However,
have the oil inspected by your SUBARU
dealer according to the maintenance
schedule in the“Warranty and Mainte-
nance Booklet”. Consult your SUBARU
dealer for details.&Recommended grade and
viscosityEach oil manufacturer has its own base
oils and additives. Never use different
brands together. For details, refer to
“Manual transmission, front differential
and rear differential gear oil”F12-6.
Continuously variable trans-
mission fluidIt is not necessary to check the transmis-
sion fluid level. Check that there are no
cracks, damage or leakage. However,
have the fluid inspected by your SUBARU
dealer according to the maintenance
schedule in the“Warranty and Mainte-
nance Booklet”. Consult your SUBARU
dealer for details.
Maintenance and service/Manual transmission oil
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(521,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
Front differential gear oil
(CVT models) and rear differ-
ential gear oilIt is not necessary to check the gear oil
level. Check that there are no cracks,
damage or leakage. However, have the oil
inspected by your SUBARU dealer ac-
cording to the maintenance schedule in
the“Warranty and Maintenance Booklet”.
Consult your SUBARU dealer for details.&Recommended grade and
viscosityEach oil manufacturer has its own base
oils and additives. Never use different
brands together. For details, refer to
“Manual transmission, front differential
and rear differential gear oil”F12-6.
CAUTION
Using a differential gear oil other
than the specified oil may cause a
decline in vehicle performance.
Power steering fluid (STI)&Checking the fluid levelThe power steering fluid expands greatly
as its temperature rises; the fluid level
differs according to fluid temperature.
Therefore, the reservoir tank has two
different checking ranges for hot and cold
fluids.
Check the power steering fluid level
monthly.
1. Park the vehicle on a level surface, and
stop the engine.
2. Check the fluid level of the reservoir
tank.
When the fluid is hot after the vehicle has
been run: Check that the oil level is
between“HOT MIN”and“HOT MAX”onthe surface of the reservoir tank.
When the fluid is cool before the vehicle is
run: Check that the oil level is between
“COLD MIN”and“COLD MAX”on the
surface of the reservoir tank.
3. If the fluid level is lower than the
applicable“MIN”line, add the recom-
mended fluid as necessary to bring the
level between the“MIN”and“MAX”line.
If the fluid level is extremely low, it may
indicate possible leakage. Consult your
SUBARU dealer for an inspection.
WARNING
Be careful not to burn yourself
because the fluid may be hot.
CAUTION
.When you add power steering
fluid, use only clean fluid, and
be careful not to allow any dirt
into the tank. And never use
different brands together.
.Be careful not to spill power
steering fluid when adding it. If
power steering fluid touches the
exhaust pipe, it may cause a bad
smell, smoke, and/or a fire. If
power steering fluid gets on the
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Maintenance and service/Front differential gear oil (CVT models) and rear differential gear oil
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(524,1)
北米Model "A1700BE-B" EDITED: 2017/ 10/ 11
Check the fluid level on the outside of the
reservoir. Because this reservoir is used
for both the brake and clutch systems and
has chambers for each system, be sure to
check the fluid level for the clutch system
at theinboard side of the reservoir
(shaded area in the illustration). If the fluid
level is below“MIN”, add the recom-
mended clutch fluid to“MAX”.
Use only clutch fluid from a sealed contain-
er.&Recommended clutch fluidRefer to“Fluids”F12-7.
CAUTION
Never use different brands of clutch
fluid together. Also, avoid mixing
DOT 3 and DOT 4 brake fluids even if
they are the same brand.
Brake boosterIf the brake booster does not operate as
described in the following, have it checked
by your SUBARU dealer.
1. With the engine off, depress the brake
pedal several times, applying the same
pedal force each time. The distance the
pedal travels should not vary.
2. With the brake pedal depressed, start
the engine. The pedal should move slightly
down to the floor.
3. With the brake pedal depressed, stop
the engine and keep the pedal depressed
for 30 seconds. The pedal height should
not change.
4. Start the engine again and run for
approximately one minute then turn it off.
Depress the brake pedal several times to
check the brake booster. The brake
booster operates properly if the pedal
stroke decreases with each depression.NOTEWhen you depress the brake pedal
strongly or suddenly, you might feel
that lighter depression of the brake
pedal generates a greater braking
force. However, even though these
occur, they do not indicate any mal-
functions, and the brake assist systemis operating properly.
Brake assist is not a system that brings
more braking ability to the vehicle
beyond its breaking capability.
Maintenance and service/Brake booster
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