2012 MERCEDES-BENZ B-CLASS engine

Fuel
Important safety notes G
WARNING
Fuel is highly flammable. If you handle fuel
incorrectly, there is a risk of fire and
explosion.
You must avoid fire, open flames, creating
sparks and smoking. Switch off the engine
and, if applicable,
the auxiliary heating before
refueling. G
WARNING
Fuel is poisonous and hazardous to health.
There is a risk of injury.
You must make

sure that fuel does not come
into contact with your skin, eyes or clothing
and that it is not swallowed. Do not inhale fuel
vapors. Keep fuel away from children.
If you or others come into contact with fuel,
observe the following:
R Wash away fuel from skin immediately
using soap and water.
R If fuel comes into contact with your eyes,
immediately rinse them thoroughly with
clean water. Seek medical assistance
without delay.
R If fuel is swallowed, seek medical
assistance without delay. Do not induce
vomiting.
R Immediately change out of clothing which
has come into contact with fuel.
Tank capacity Model Total
capacity B 250 BlueEFFICIENCY
13.2 US gal
(50.0 l) Model Of which
reserve B 250 BlueEFFICIENCY
Approx.
1.6 US gal (6.0 l) Gasoline
Fuel grade
!
Do not use

diesel to refuel vehicles with a
gasoline engine. Do not switch on the
ignition if you accidentally refuel with the
wrong fuel. Otherwise, the fuel will enter
the fuel system. Even small amounts of the
wrong fuel could result in damage to the
fuel system and the engine. The repair
costs are high. Notify a qualified specialist
workshop and have the fuel tank and fuel
lines drained completely.
! You should only refuel with unleaded
premium-grade gasoline as this avoids
damaging the catalytic converter.
If engine running problems are apparent,
have the cause checked immediately and
repaired. Excess unburned fuel can
otherwise enter the catalytic converter,
leading to overheating and possibly
causing a fire.
! To ensure the longevity and full
performance of the engine, only premium-
grade unleaded gasoline may be used.
If there is no premium-grade unleaded
gasoline available and regular unleaded
gasoline must be used, please observe the
following precautions:
R only fill the fuel tank to half full with
regular unleaded gasoline and fill the rest
with premium-grade unleaded gasoline
as soon as possible.
R do not drive at the maximum speed.
R avoid sudden acceleration.330
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R
if the vehicle
is carrying a light load, e.g.
two passengers without luggage, do not
allow the engine to rev above 3000 rpm.
R if the vehicle is fully loaded or is being
operated in mountainous terrain, do not
depress the accelerator pedal further
than Ô of the pedal travel.
Only refuel using premium-grade unleaded
gasoline with a minimum octane rating of 91.
Reformulated Gasoline (RFG) and/or
unleaded gasoline with additives can be used.
The concentration of additives in the fuel,
however, must not exceed 10%, e.g.:
R Ethanol
R TAME
R ETBE
R IPA
R TBA
For MTBE, the concentration should not
exceed 15%.
The concentration of methanol in gasoline,
including other additives, must not exceed
3%.
Using mixtures of methanol and ethanol is not
permitted. Gasohol, a mixture of 10% ethanol
and 90% unleaded gasoline, may be used.
All of these blends must fulfill the fuel
requirements, e.g.:
R knock resistance
R boiling point
R vapor pressure
You will usually find information about the fuel
grade on the pump. If you cannot find the
label on the pump, ask the staff for
assistance.
i For more information, contact a qualified
specialist workshop.
Information on refueling (Y page 147).
Additives
! Operating the engine with fuel additives
can increase wear and tear to the fuel
system high-pressure pump and lead to contamination of the entire fuel system.
The repair costs are high. This does not
include additives for the removal and
prevention of residue buildup. gasoline
must only be mixed with additives
recommended by Mercedes-Benz. More
information about
recommended
additives
can be obtained from any authorized
Mercedes-Benz Center.
One of the main problems of poor fuel quality
is the forming of deposits that are created
during the gasoline combustion process.
Mercedes-Benz recommends that you use
branded fuels that have additives.
If you use fuels without these additives over
a longer period of time, carbon deposits may
build up. These deposits form at the inlet
valves and in the combustion chamber in
particular.
This could lead to engine problems, e.g.:
R longer engine warm-up phase
R uneven idle
R engine noise
R misfiring
R loss of power
Carbon deposits may form if the availability
of gasoline with relevant additives is
insufficient (in certain regions). In this case,
Mercedes-Benz recommends additives
approved for use in Mercedes-Benz vehicles;
see http://bevo.mercedes-benz.com.
For a list of approved products, consult an
authorized Mercedes-Benz Center. Comply
with the instructions for use on the product
label.
Do not mix other fuel additives with fuel. This
causes unnecessary costs and could damage
the engine. Service products and filling capacities
331
Technical data Z
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Engine oil
General notes !
Never use engine oil or an oil filter of a
specification other than is necessary to
fulfill the prescribed service intervals. Do
not change the engine oil or oil filter in
order to achieve longer replacement
intervals than those prescribed. You could
otherwise cause engine
damage or damage
to the exhaust gas aftertreatment.
Follow the instructions in the service
interval display regarding the oil change.
Otherwise, you may damage the engine and
the exhaust gas aftertreatment.
When handling engine oil, observe the
important safety notes on service products
(Y page 329).
The engine oils are matched to the
performance of Mercedes-Benz engines and
service intervals. You should therefore only
use engine oils and oil filters that are
approved for vehicles with maintenance
systems.
For a list of approved engine oils and oil filters,
consult an authorized Mercedes-Benz
Center. Or visit the website
http://bevo.mercedes-benz.com.
The table shows which engine oils have been
approved for your vehicle. Model Engine
model MB
Approval B 250
BlueEFFICIENCY
270 229.5
i
MB approval is indicated on the oil
containers.
Filling capacities The following values refer to an oil change
including the oil filter.
Model Capacity
B 250 BlueEFFICIENCY
5.9 US qt (
5.6 l) Additives
!
Do not use

any additives in the engine oil.
This could damage the engine.
Engine oil viscosity Viscosity describes the flow characteristics
of a
fluid.

If an engine oil has a high viscosity,
this means that it is thick; a low viscosity
means that it is thin.
Select an engine oil with an SAE classification
(viscosity) suitable for the prevailing outside
temperatures. The table shows you which
SAE classifications are to be used. The low-
temperature characteristics of engine oils
can deteriorate significantly, e.g. as a result
of aging, soot and fuel deposits. It is therefore
strongly recommended that you carry out
regular oil changes using an approved engine
oil with the appropriate SAE classification. Brake fluid
G
WARNING
The brake fluid constantly absorbs moisture
from the air. This lowers the boiling point of
the brake fluid.

If the boiling point of the brake
fluid is too low, vapor pockets may form in the
brake system when the brakes are applied
hard. This would impair braking efficiency.
There is a risk of an accident.
You should have the brake fluid renewed at
the specified intervals. 332
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When handling brake fluid, observe the
important safety notes on service products
(Y page 329).
The brake
fluid
change intervals can be found
in the Maintenance Booklet.
Only use brake fluid approved by Mercedes-
Benz according to MB Approval 331.0.
Information about approved brake fluid can
be obtained at any qualified specialist
workshop or on the Internet at
http://bevo.mercedes-benz.com.
i Have the brake fluid renewed regularly at
a qualified specialist workshop. Coolant
Important safety notes G
WARNING
If antifreeze comes into contact with hot
components in the engine compartment, it
may ignite. There is a risk of fire and injury.
Let the engine cool down before you add
antifreeze. Make sure that antifreeze is not
spilled next to the filler neck. Thoroughly
clean the antifreeze

from components before
starting the engine.
! Only add coolant that has been premixed
with the desired antifreeze protection. You
could otherwise damage the engine.
Further information on coolants can be
found in the Mercedes-Benz Specifications
for Service Products, MB Specifications for
Service Products 310.1, e.g. on the
Internet at
http://bevo.mercedes-benz.com. Or
contact a qualified specialist workshop.
! Always use a suitable coolant mixture,
even in countries where high temperatures
prevail.
Otherwise, the engine cooling system is not
sufficiently protected from corrosion and
overheating. When handling coolant, observe the
important safety notes on service products
(Y page 329).
The coolant is a mixture of water and
antifreeze/corrosion inhibitor. It performs
the following tasks:
R
corrosion protection
R antifreeze protection
R raising the boiling point
If the coolant

has antifreeze protection down
to -35 ‡ (-37 †), the boiling point of the
coolant during operation is approximately
266 ‡ (130 †).
The antifreeze/corrosion inhibitor
concentration in the engine cooling system
should:
R be at least 50%. This will protect the engine
cooling system against freezing down to
approximately -35 ‡ (-37 †).
R not exceed 55% (antifreeze protection
down to -49 ‡ [-45 †]). Otherwise, heat
will not be dissipated as effectively.
If the vehicle has lost coolant, add equal
amounts of water and antifreeze/corrosion
inhibitor.
Mercedes-Benz recommends an antifreeze/
corrosion inhibitor concentrate in
accordance with MB Specifications for
Service Products 310.1.
The coolant is checked with every
maintenance interval at a qualified specialist
workshop.
i When the vehicle is first delivered, it is
filled with a coolant mixture that ensures
adequate antifreeze and corrosion
protection.
Filling capacities Model Capacity
B 250
BlueEFFICIENCY
Approx. 8.2 US qt
(7.8 l) Service products and filling capacities
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i
Use antifreeze/corrosion inhibitor
according to MB approval 325.0 or 326.0. Windshield washer system and
headlamp cleaning system
Important safety notes G
WARNING
Windshield washer concentrate is highly
flammable. If it comes into contact with hot
engine components or the exhaust system it
could ignite. There is a risk of fire and injury.
Make sure that no windshield washer
concentrate is spilled next to the filler neck.
! Only use washer fluid that is suitable for
plastic lamp lenses, e.g. MB SummerFit or
MB WinterFit. Unsuitable washer fluid
could damage the plastic lenses of the
headlamps.
! Do not add
distilled or de-ionized water to
the washer fluid container. Otherwise, the
level sensor may be damaged.
! Only MB SummerFit and MB WinterFit
washer fluid should be mixed together. The
spray nozzles may otherwise become
blocked.
When handling washer fluid, observe the
important safety notes on service products
(Y page 329).
At temperatures above freezing:
X Fill the washer fluid reservoir with a mixture
of water and windshield washer fluid, e.g.
MB SummerFit.
Add 1 part MB SummerFit to 100 parts water. At temperatures below freezing:
X
Fill the washer fluid reservoir with a mixture
of water and washer fluid, e.g. MB
WinterFit.
Adapt the mixing ratio to the outside
temperature.
R Down to 14 ‡ (Ò

10 †): mix 1 part MB
WinterFit with 2 parts water.
R Down to Ò4 ‡ (Ò20 †): mix 1 part MB
WinterFit with 1 part water.
R Down to Ò20.2 ‡ (Ò29 †): mix 2 parts MB
WinterFit with 1 part water.
i Add windshield washer fluid, e.g. MB
SummerFit or MB WinterFit, to the washer
fluid all year round. Climate control system refrigerant
Important safety notes Type of refrigerant
The instruction label about types of
refrigerants can be found on the radiator
cross member.
Refrigerant R-134a
!
Only use refrigerant R-134a and PAG oil
(part number A0019890803) which has
been approved by Mercedes-Benz. The
approved R-134a PAG

oil may not be mixed
with other conventional PAG oils.
Otherwise, the climate control system may
be damaged.
Service work, such as topping-up refrigerant
or replacing components, may only be carried
out by a qualified specialist workshop. All
applicable regulations must be adhered to,
SAE standard J639 included.
Always have work on the climate control
system carried out at a qualified specialist
workshop. 334
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