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258 Engine compartment
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Adding coolant
If coola nt h as to be ad ded, a 50 / 50 m ixtu re of wa ter and
MB anticorrosion / antifreeze should be added.
The drain plugs for the cooling system are located on
the right side of the engine block and at the bottom of
the radiator.
Anticorrosion / antifreeze mixture, see page 322.
Wa r n i n g !
In order to avoid possible serious burns or injury:
• Use extreme caution when opening the hood if
there are any signs of steam or coolant leaking
from the cooling system, or if the coolant
temperature gauge indicates that the coolant is
overheated.• Do not remove pressure cap on coolant
reservoir if engine temperature is above 194°F
(90°C). Allow engine to cool down before
removing cap. The coolant reservoir contains
hot fluid and is under pressure.
• Using a rag, slowly open cap approximately
1/2 turn to relieve excess pressure. If opened
immediately, scalding hot fluid and steam will
be blown out under pressure.• Do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which may
burn if it comes into contact with hot engine
parts.
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302 Cleaning and care of the vehicle
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Cleaning and care of the vehicle
In operation, your vehicle is subjected to varying
external inf luences which, if gone unchecked, can
attack the paintwork as well as the underbody and
cause lasting damage.
Such damage is caused not only by extreme and varying
climatic conditions, but also by air polution, road salt,
tar, gravel and stone chipping. Grease and oil, fuel,
coolant, brake fluid, bird droppings, insects, tree resins
etc. should be removed immediately to avoid paint
damage. Frequent washing reduces and/or eliminates
the aggressiveness and potency of the above adverse
influences.More frequent washings are necessary to deal with
unfavorable conditions; for example, near the ocean, in
industrial areas (smoke, exhaust emissions), or during
winter operation.
You should check your vehicle from time to time for
stone chipping or other damage. Any damage should be
repaired as soon as possible to prevent the start of
corrosion.
In doing so, do not neglect the underside of the vehicle.
A prerequisite for a thorough check is a washing of the
underbody followed by a thorough inspection. Damaged
areas need to be reundercoated.
Your vehicle has been treated at the factory with a wax-
base ru stproof ing in th e body cavities w hich will la st for
the lifetime of the vehicle. Post-production treatment is
neither necessary nor recommended by Mercedes-Benz
because of the possibility of incompatibility between
materials used in the production process and others
applied later.
We have selected car-care products and compiled
recommendations which are specially matched to our
vehicles and which always reflect the latest technology.
You can obtain Mercedes-Benz approved car-care
products at your authorized Mercedes-Benz Center.
Wa r n i n g !
Many cleaning products can be hazardous. Some
are poisonous, others are flammable. Always follow
the instructions on the particular container.
Always open your vehicle’s doors or windows when
cleaning the inside.Never use fluids or solvents that are not designed
for cleaning your vehicle.
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309 Contents – Technical data
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Technical dataSpare parts service ........................ 310
Warranty coverage ......................... 310
Identification labels ....................... 311
Layout of poly-V-belt drive ............ 312
Technical data ................................ 313
Fuels, coolants, lubricants etc. –
capacities ................................... 317
Engine oils ...................................... 319Engine oil additives .......................319
Air conditioner
refrigerant .................................. 319
Brake fluid ....................................... 319
Premium unleaded
gasoline ...................................... 320
Fuel requirements ........................ 320
Gasoline additives ......................... 321
Coolants .......................................... 321
Consumer information ................. 323
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312 Technical data
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CLK 320 shown
3VIN, visible (lower edge of windshield)
4Engine number
5Body number and paintwork number
6Emission control label
7Information label, California version
Vacuum line routing for emission control systemLayout of poly-V-belt drive
1Automatic belt tensioner
2Crankshaft
3Air conditioner compressor
4Coolant pump
5Generator (alternator)
6Idler pulley
7Power steering pump
6
5
7
3
4
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317 Fuels, coolants, lubricants etc. - capacities
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Veh icle c omponents and t heir respec tive lub rica nts mu st ma tch . T herefore u se only brands tested and rec omm end ed
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)8.5 US qt (8.0 l)
Automatic transmission
(automatic transmission fluid)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 U S q t (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 Anticorrosion/antifreeze)CLK 320
CLK 430approx. 9.5 US qt (9.0 l)
a p p r o x . 11 . 7 U S q t ( 11 . 1 l )
Page 321 of 341
318 Fuels, coolants, lubricants etc. - capacities
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Windshield washer system
(MB Windshield washer concentrate “S”
1)approx. 7.4 US qt (7.0 l)
Fuel tank
including a reserve of
(Premium unleaded gasoline:
Posted Octane 91 (Avg. of 96 RON/86 MON))approx. 16.4 US gal (62.0 l)
approx. 2.1 US gal (8.0 l)
Air conditioner system
(R-134a refrigerant and special
PA C l u b r i c a n t (Never R-12))
1 Use MB Windshield Washer Concentrate “S” and water for temperatures above freezing or MB Windshield Washer Concentrate “S” and
commercially available premixed windshield washer solvent/antifreeze for temperatures below freezing. Follow suggested mixing ratios, see
page 259.Fuels, coolants, lubricants etc. Model Capacity
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319 Fuels, coolants, lubricants etc.
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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 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
War ra nt y.Air conditioner refrigerant
R-134a (H FC) ref rigerant a nd special PAG l ubricating 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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320 Fuels, coolants, lubricants etc.
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Premium unleaded gasoline
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
standa rd 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..