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!
Do not ignore the low engine coolant level warning. Extended driving with the message
and
symbol displayed may cause serious engine damage not covered by the Mercedes-Benz
Limited Warranty.
Do not drive without sufficient amount of coolant in the cooling system. The engine will
overheat causing major engine damage. Display messages
Possible causes/consequences and
X Solutions? Coolant
Stop,
turn
engine
off. The coolant is too hot.
X
Stop the vehicle immediately as soon as it is safe to do so.
X Turn off the engine immediately.
X Engage the parking brake.
X Only start the engine again after the message disappears.
You could otherwise damage the engine.
X Observe the coolant temperature in the multifunction
display.
X If the temperature rises again: Contact an authorized
Mercedes-Benz Center immediately.
During severe operation conditions and stop-and-go city
traffic, the coolant temperature may rise close to 248‡
(120†). G
Warning!
Driving when your engine is overheated can cause some fluids which may have leaked into the
engine compartment to catch fire. You could be seriously burned.
Steam
from an overheated engine can cause serious burns which can occur just by opening the
engine hood. Stay away from the engine if you see or hear steam coming from it.
Stop the vehicle in a safe location away from other traffic. Turn off the engine, get out of the
vehicle and do not stand near the vehicle until the engine has cooled down.
! The engine should not be operated with the coolant temperature above 248‡ (120†).
Doing so may cause serious damage which is not covered by the Mercedes-Benz Limited
Warranty. 248
Vehicle status messages in the multifunction display
Practical hints
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of these oxygenates to gasoline does not
exceed 10%; MTBE must not exceed 15%.
The ratio of methanol to gasoline must not
exceed 3% plus additional cosolvents.
Using
mixtures of ethanol and methanol is not
allowed. Gasohol, which contains 10%
ethanol and 90% unleaded gasoline, can be
used.
These blends must also meet all other fuel
requirements, such as resistance to spark
knock, boiling range, vapor pressure, etc. Gasoline additives
A major concern among engine
manufacturers is carbon build-up caused by
gasoline. Mercedes-Benz recommends only
the use of quality gasoline containing
additives that prevent the build-up of carbon
deposits.
After an extended period of using fuels
without such additives carbon deposits can
build up, especially on the intake valves and
in the combustion area, leading to engine
performance problems such as:
R Warm-up hesitation
R Unstable idle
R Knocking/pinging
R Misfire
R Power loss
In areas where carbon deposits may be
encountered due to lack of availability of
gasoline which contains these additives, the
use of Mercedes-Benz approved additives is
recommended.
Contact
an authorized Mercedes-Benz Center
or visit www.mbusa.com (USA only) for a
listing of approved products. Follow
directions on the product label.
Do not blend other fuel additives with fuel.
This only results in unnecessary cost and may
be harmful to the engine operation. !
Damage or malfunction resulting from
poor
fuel quality or from blending additional
fuel additives other than those tested and
approved by us for use on Mercedes-Benz
vehicles are not covered by the Mercedes-
Benz Limited Warranty or by any pre-owned
or Extended Limited Warranties. Coolants
The engine coolant is a mixture of water and
anticorrosion/antifreeze, which provides:
R Corrosion protection
R Freeze protection
R Boiling
protection (by increasing the boiling
point)
The cooling system was filled at the factory
with a coolant providing freeze protection to
approximately -35‡ (-37†) and corrosion
protection.
! Add premixed coolant solution only.
Adding water and MB 325.0 Anticorrosion/
Antifreeze separately from each other,
could cause engine damage not covered by
the Mercedes-Benz Limited Warranty.
If the antifreeze mixture is effective to -35‡
(-37†), the boiling point of the coolant in the
pressurized cooling system is reached at
approximately 266‡ (130†).
The coolant solution must be used year round
to provide the necessary corrosion protection
and increase boil-over protection. Refer to
the Maintenance Booklet for replacement
interval.
Coolant system design and coolant used
determine the replacement interval. The
replacement interval published in the
Maintenance Booklet is only applicable if
MB 325.0 Anticorrosion/Antifreeze solution
or other Mercedes-Benz approved products
of equal specification are used to renew the
coolant concentration or bring it back up to
the proper level. 304
Fuels, coolants, lubricants, etc.
Technical data
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For information on other Mercedes-Benz
approved products of equal specification,
contact
an authorized Mercedes-Benz Center
or visit www.mbusa.com (USA only).
To provide important corrosion protection,
the solution must be at least 50%
anticorrosion/antifreeze (equivalent to
freeze protection to approximately -35‡
[-37†]).
If you use a solution that is more than 55%
anticorrosion/antifreeze (freeze protection
to approximately -49‡ [-45†]), the engine
temperature will increase due to the lower
heat transfer capability of the solution.
Therefore, do not use more than this amount
of anticorrosion/antifreeze.
If the coolant level is low, water and MB 325.0
Anticorrosion/Antifreeze should be used to
bring it up to the proper level (have cooling
system checked for signs of leakage). Please
make sure the mixture is in accordance with
label instructions.
The water in the cooling system must meet
minimum requirements, which are usually
satisfied by normal drinking water. If you are not sure about the water quality,
contact an authorized Mercedes-Benz
Center.
Anticorrosion/antifreeze Your vehicle contains a number of aluminum
parts. The use of aluminum components in
motor vehicle engines necessitates that
anticorrosion/antifreeze coolant used in
such engines be specifically formulated to
protect the aluminum parts. Failure to use
such anticorrosion/antifreeze coolant will
result
in a significantly shortened service life.
Therefore, the following product is strongly
recommended for use in your vehicle:
MB 325.0 Anticorrosion/Antifreeze agent.
Before the start of the winter season (or once
a year in hot southern regions), you should
have the anticorrosion/antifreeze
concentration checked.
The coolant is also regularly checked each
time you bring your vehicle to an authorized
Mercedes-Benz Center for service. Model Approximate freeze protection
-35‡ (-37†) -49‡ (-45†)
Cooling system
SLK 300
SLK 350 5.2 US qt (4.9 l) 5.7 US qt (5.4 l)
SLK 55 AMG 5.9 US qt (5.55 l) 6.5 US qt (6.1 l)Fuels, coolants, lubricants, etc.
305
Technical data
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