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Engine compartment
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Hood
Warning!
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 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.To o pen :
To unlock the hood, pull release lever (1) under the
driver’s side of the instrument panel. At the same time a
handle will extend out of the radiator grill (it may be
necessary to lift the hood up slightly).
Caution!
To avoid damage to the windshield wiper or hood, open
the hood only with wiper in the parked position.
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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 2.1 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 page222 if
an engine oil level display appears on the multifunction
display when the engine is running.
Note:
See page110for engine oil level indicator.
Mercedes-Benz
Mercedes-Benz
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Cleaning and care of the vehicle
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cluster displayPractical hintsCar careIndex Scratches, corrosive deposits, corrosion or damage due
to negligent or incorrect care cannot always be removed
or repaired with the car-care products recommended
here. In such cases it is best to seek aid at your
authorized Mercedes-Benz Center.
The following topics deal with the cleaning and care of
your vehicle and give important “how-to” information as
well as references to Mercedes-Benz approved car-care
products.
Additional information can be found in the booklet titled
“Vehicle Care Guide”.
Engine cleaning
Prior to cleaning the engine compartment make sure to
protect electrical components and connectors from the
intrusion of water and cleaning agents.
Corrosion protection, such as MB Anticorrosion Wax
should be applied to the engine compartment after
every engine cleaning. Before applying, all control
linkage bushings and joints should be lubricated. The
poly-V-belt and all pulleys should be protected from any
wax.Vehicle washing
Do not use hot water or wash your vehicle in direct
sunlight. Use only a mild car wash detergent, such as
Mercedes-Benz approved Car Shampoo.
Thoroughly spray the vehicle with a diffused jet of
water. Direct only a very weak spray towards the
ventilation intake. Use plenty of water and rinse the
sponge and chamois frequently.
Rinse with clear water and thoroughly wipe dry with a
chamois. Do not allow cleaning agents to dry on the
finish.
In the winter, thoroughly remove all traces of road salt
as soon as possible.
When washing the underbody, do not forget to clean the
inner sides of the wheels.
Plastic and rubber parts
Do not use oil or wax on these parts.
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Technical dataSpare parts service 300
Warranty coverage 300
Identification labels 301
Layout of poly-V-belt drive 302
Technical data 303
Fuels, coolants, lubricants etc. – capacities 307
Engine oils 309
Engine oil additives 309
Air conditioner refrigerant 309
Brake fluid 309
Premium unleaded gasoline 310
Fuel requirements 310
Gasoline additives 311
Coolants 311
Consumer information 313
Uniform tire quality grading 313
Index 315
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Fuels, coolants, lubricants etc. - capacities
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cluster displayPractical hints Car care Index 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)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 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 Anticorrosion/antifreeze)CLK 320
CLK 430approx. 9.5 US qt (9.0 l)
approx. 11.7 US qt (11.1 l)
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Fuels, coolants, lubricants etc.
Te ch n ica l
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cluster displayPractical hints Car care Index 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 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 (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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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
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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Fuels, coolants, lubricants etc.
Te ch n ica l
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cluster displayPractical hints Car care Index 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 in the
boil-over protection. You should have it replaced every
3years.
To provide the important corrosion protection, the
solution must be at least 45% anticorrosion/antifreeze
(equals a freeze protection to approx. - 22°F [-30°C]). If
you use a solution that is more than 55% anticorrosion/
antifreeze (freeze protection to approx. - 49°F [-45°C]),
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