250 Engine compartment
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Hood
Wa r n i n g !
To help prevent personal injury, stay clear of
moving parts when the hood is open and the engine
is running. Be sure the hood is properly closed
before driving. When closing hood, use extreme
caution not to catch hands or fingers.The radiator fan may continue to run for
approximately 30 seconds or even restart after the
engine has been turned off. Stay clear from fan
blades.
The engine is equipped with a transistorized
ignition system. Because of the high voltage it is
dangerous to touch any components (ignition coils,
spark plug sockets, diagnostic socket) of the
ignition system
• with the engine running,
• while starting the engine,
• if ignition is “on” and the engine is turned
manually.If you see flames, steam or smoke coming from the
engine compartment, or if the coolant temperature
gauge indicates that the engine is overheated, do
not open the hood. Move away from vehicle and do
not open the hood until the engine has cooled. If
necessary, call a fire department.
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252 Engine compartment
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Checking engine oil level (CLK 320 shown)
1Oil dipstick
2Oil filler cap
To check the engine oil level, park vehicle on level
ground, with engine at normal operational temperature.
Check engine oil level approximately 5 minutes after
stopping the engine, allowing for the oil to return to the
oil pan.Wipe oil dipstick clean prior to checking the engine oil
level. Fully insert dipstick in tube, and remove after
three seconds to obtain accurate reading.
Oil level must be between the
lower (min) and upper (max) mark of
the dipstick.
Fill quantity between upper and lower dipstick marking
level is approximately 2.0 US qt (2.0 l).
Do not overfill the engine.
Excessive oil must be drained
or siphoned. It could cause damage to engine and
catalytic converter not covered by the Mercedes-Benz
Limited Warranty.
See malfunction and warning messages on page 230 if
an engine oil level display appears on the multifunction
display when the engine is running.
Note:
See page 108 for engine oil level indicator.
Mercedes-Benz
Mercedes-Benz
2
1
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Technical dataSpare parts service ........................308
Warranty coverage .........................308
Identification labels .......................309
Layout of poly-V-belt drive ............ 310
Technical data ................................ 311
Fuels, coolants, lubricants etc. –
capacities ................................... 316
Engine oils ...................................... 318Engine oil additives ....................... 318
Air conditioner refrigerant ........... 318
Brake fluid ....................................... 318
Premium unleaded gasoline ......... 319
Fuel requirements ......................... 319
Gasoline additives ......................... 320
Coolants .......................................... 320
Consumer information ................. 322
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316 Fuels, coolants, lubricants etc. - capacities
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Fuels, coolants, lubricants etc. – capacities
Vehicle components and their respective lubricants must match. Therefore use only brands tested and recommended
by us. Please refer to the Factory Approved Service Products pamphlet, or inquire at your Mercedes-Benz Center.
Fuels, coolants, lubricants etc. Model Capacity
Engine with oil filter
(recommended engine oils)CLK 320, CLK 430 8.5 US qt (8.0 l)
Automatic transmission
(automatic transmission fluid)
1
CLK 320
CLK 4308.5 US qt (8.0 l)
9.6 US qt (9.1 l)
Rear axle
(Hypoid gear oil SAE 90, 85 W 90)1.4 US qt (1.3 l)
Power steering
(MB Power steering fluid)approx. 1.1 US qt (1.0 l)
Front wheel hubs
(high temperature roller bearing grease)approx. 2.1 oz (60 g) each
Brake system
(MB Brake fluid (DOT 4))approx. 0.5 US qt (0.5 l)
Cooling system
(MB 325.0 Anticorrosion/Antifreeze Agent)CLK 320
CLK 430approx. 9.5 US qt (9.0 l)
approx. 11.7 US qt (11.1 l)
1 MB part no. 001 989 21 03 10.
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318 Fuels, coolants, lubricants etc.
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Engine oils
Engine oils are specifically tested for their suitability in
our engines. Therefore, use only engine oils
recommended by Mercedes-Benz. Information on
recommended brands is available in the Factory
Approved Service Products pamphlet or at your
authorized Mercedes-Benz Center.
Please follow Service Booklet recommendations for
scheduled oil changes. Failure to do so could result in
engine damage not covered by the Mercedes-Benz
Limited Warranty.
Engine oil additives
Do not blend oil additives with engine oil. They may be
harmful to the engine operation.
Damage or malfunctions resulting from blending oil
additives are not covered by the Mercedes-Benz Limited
Warranty.Air conditioner refrigerant
R-134a (HFC) refrigerant and special PAG lubricating oil
is used in the air conditioner system.
Never use R-12 (CFC) or mineral-based lubricating oil,
otherwise damage to the system will occur.
Brake fluid
During vehicle operation, the boiling point of the brake
fluid is continuously reduced through the absorption of
moisture from the atmosphere. Under extremely hard
operating conditions, this moisture content can lead to
the formation of bubbles in the system thus reducing
the system’s efficiency.
The brake fluid must therefore be replaced every two
years, preferably in the spring.
It is recommended to use only brake fluid approved by
Mercedes-Benz. Your authorized Mercedes-Benz Center
will provide you with additional information.
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319 Fuels, coolants, lubricants etc.
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Caution!
To maintain the engine’s durability and performance,
premium unleaded gasoline must be used. If premium
unleaded is not available and low octane fuel is used,
follow these precautions:
•Have the fuel tank filled only partially with
unleaded regular and fill up with premium
unleaded as soon as possible.
•Avoid full throttle driving and abrupt acceleration.
•Do not exceed an engine speed of 3000 rpm, if the
vehicle is loaded with a light load such as two
persons and no luggage.
•Do not exceed 2/3 of maximum accelerator pedal
position, if the vehicle is fully loaded or operating in
mountainous terrain.Fuel requirements
Use only Premium unleaded meeting ASTM
standard D 439:
The octane number (posted at the pump) must be
91 min. It is an average of both the Research (R) octane
number and the Motor (M) octane number: [(R+M)/2].
This is also known as ANTI-KNOCK INDEX.
Unleaded gasoline containing oxygenates such as
Ethanol, IPA, IBA and TBA can be used provided the
ratio of any one of these oxygenates to gasoline does not
exceed 10%, MTBE not to 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..
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320 Fuels, coolants, lubricants etc.
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Gasoline additives
A major concern among engine manufacturers is carbon
build up caused by gasoline. Mercedes-Benz
recommends the use of only 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:
•Warm-up hesitation
•Unstable idle
•Knocking/pinging
•Misfire
•Power loss
Do not blend other specific fuel additives with fuel.
They only result in unnecessary cost, and may be
harmful to the engine operation.
Damage or malfunctions resulting from poor fuel
quality or from blending specific fuel additives are not
covered by the Mercedes-Benz Limited Warranty.Coolants
The engine coolant is a mixture of water and
anticorrosion/antifreeze, which provides:
•Corrosion protection
•Freeze protection
•Boiling protection (by increasing the boiling point)
The cooling system was filled at the factory with a
coolant providing freeze protection to approximately
-22
°F (-30
°C) and corrosion protection.
If the antifreeze mixture is effective to -22
°F (-30
°C), the
boiling point of the coolant in the pressurized cooling
system is reached at approximately 266
°F (130
°C).
The coolant solution must be used year-round to provide
the necessary corrosion protection and increase boil-
over protection. You should have it replaced every 15
years or 150 000 miles (250 000 km), whichever comes
first. Coolant system design and coolant used stipulate
the replacement interval. The above replacement
interval is only applicable if MB 325.0 anticorrosion/
antifreeze solution or other Mercedes-Benz approved
products of equal specification (see Factory Approved
Service Products pamphlet) are used to renew the
coolant concentration or bring it back up to the proper
level.
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CCapacities
Fuels, coolants, lubricants etc. ............................... 316
Cargo tie-down rings ..................................................... 152
Catalytic converter......................................................... 176
CD changer
See Audio system ...................................................... 136
Cellular telephone ......................................................... 153
Center console .................................................................. 18
Central locking switch .................................................... 33
Central locking system ................................................... 25
Automatic central locking ......................................... 34
Choosing global or selective mode........................... 28
Electronic key .............................................................. 23
Locking and unlocking............................................... 27
Mechanical keys ........................................................... 30
Remote control ............................................................ 25
Changing wheels ........................................................... 263
CHECK ENGINE malfunction indicator lamp............ 224
Check regularly and before a long trip ...................... 222
Checking engine oil level
Via engine oil level indicator .................................. 108
Via oil dipstick........................................................... 252Child restraint .............................................. 53, 58, 59, 69
Child seat
See Infant and child restraint systems .................... 69
Cleaning and care of the vehicle ................................ 300
Clock, setting .................................................................. 102
COMAND, radio and telephone.................................... 174
Combination switch ....................................................... 113
Consumer information ................................................. 322
Control and operation of radio transmitters .............. 174
COOLANT (coolant level) - malfunction and warning
messages ................................................................... 236
Coolant level
Adding coolant.......................................................... 254
Checking .................................................................... 253
COOLANT TEMP. (coolant temperature) - malfunction
and warning messages ............................................ 237
Coolant temperature gauge ............................................ 82
Coolants .......................................................................... 320
Anticorrosion/antifreeze quantity ........................ 320
Cruise control ................................................................. 210
Cup holder
Center console, front ................................................ 149
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