2004 MERCEDES-BENZ CLK-CLASS engine coolant

292 OperationEngine compartmentCoolant
The engine coolant is a mixture of water
and anticorrosion/antifreeze. To check
the coolant level, the vehicle must be
parked on level ground and the engine
must be cool.
The coolant expansion tank is located on
the passenger side of the engine compart-
ment.
1Coolant expansion tank

Using a rag, turn the cap slowly approx-
imately one half turn to the left to re-
lease any excess pressure.

Continue turning the cap to the left and
remove it.
Warning!
G
In order to avoid any possibly serious burns:

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 indi-
cates 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 the cap approx-
imately
1⁄2 turn to relieve excess pres-
sure. If opened immediately, scalding
hot fluid and steam will be blown out un-
der pressure.


Do not spill antifreeze on hot engine
parts. Antifreeze contains ethylene gly-
col which may burn if it comes into con-
tact with hot engine parts.
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293 Operation
Engine compartment
The coolant level is correct if the level

for cold coolant: reaches the black top
part of the reservoir


for warm coolant: is approx. 0.6 in
(1.5 cm) higher

Add coolant as required.

Replace and tighten cap.
More information on coolant can be found
in the “Technical data” section
(
page 414).
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315 Practical hints
What to do if …?
Problem
Possible cause
Suggested solution
•
The red coolant warning lamp
comes on when the engine is
running.
There is insufficient coolant in the reservoir.

Add coolant to prevent engine from
overheating (
page 292).
If this warning lamp comes on frequently,
there is a leak in the cooling system.

Have the cooling system checked.
If the coolant level is correct, the electric ra-
diator fan may be broken.

If the coolant temperature is below
257 °F (125 °C), you can continue
driving to the nearest authorized
Mercedes-Benz Center.

Avoid high engine loads (e.g. driving
uphill) and stop-and-go driving.
•
The red coolant warning lamp
comes on while driving and you
hear a warning sound.
The coolant temperature has exceeded
257 °F (125 °C).

Stop as soon as possible and allow
the engine and coolant to cool down.
Warning!
G
Driving when your engine is badly overheat-
ed 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 and can occur just by opening
the hood. Stay away from the engine if you
see or hear steam coming from it.
Turn off the engine, get out of the vehicle
and do not stand near the vehicle until the
engine has cooled down.
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328 Practical hintsWhat to do if …?Display symbol
Display message
Possible cause
Possible solution
?
Visit workshop!
There may be a malfunction in the

fuel injection system


ignition system


exhaust system


fuel system

Have the measuring system checked
by an authorized Mercedes-Benz Cen-
ter.
B
Coolant
Check level
The coolant level is too low.

Add coolant (
page 292).

If you have to add coolant frequently,
have the cooling system checked by
an authorized Mercedes-Benz Center.
Warning!
G
Do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts. You can be seriously burned.
!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 en-
gine damage.
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329 Practical hints
What to do if …?
During severe operating conditions and
stop-and-go city traffic, the coolant tem-
perature may rise close to 248°F (120°C).
Display symbol
Display message
Possible cause
Possible solution
Ï
Coolant
Stop, engine off!
The coolant is too hot.

Stop the vehicle and turn off the en-
gine.

Only start the engine again after the
message disappears. You could other-
wise damage the engine.
Warning!
G
Driving when your engine is badly overheat-
ed 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 and can occur just by opening
the hood. Stay away from the engine if you
see or hear steam coming from it.
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°F
(120°C). Doing so may cause serious
engine damage which is not covered by
the Mercedes-Benz Limited Warranty.
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330 Practical hintsWhat to do if …?Display symbol
Display message
Possible cause
Possible solution
Ï
Coolant
Stop, engine off!
The poly-V-belt could be broken.

Stop immediately and check the
poly-V-belt.
If it is broken:

Do not continue to drive. Otherwise
the engine will overheat due to an in-
operative water pump which may re-
sult in damage to the engine. Notify an
authorized Mercedes-Benz Center.
If it is intact:

Do not continue to drive the vehicle
with this message displayed. Doing so
could result in serious engine damage
that is not covered by the
Mercedes-Benz Limited Warranty.
Coolant
Visit workshop
The cooling fan for the coolant is malfunc-
tioning.

Observe the coolant temperature dis-
play.

Have the fan replaced as soon as pos-
sible.
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397 Technical data
Spare parts service
Warranty coverage
Identification labels
Layout of poly-V-belt drive
Engine
Rims and tires
Electrical system
Main dimensions
Weights
Fuels, coolants, lubricants, etc.
Consumer information
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410 Technical dataFuels, coolants, lubricants, etc.
Fuels, coolants, lubricants, etc.CapacitiesVehicle components and their respective
lubricants must match. Therefore only use
brands tested and approved by
Mercedes-Benz.Please refer to the Factory Approved Ser-
vice Products pamphlet, or inquire at your
Mercedes-Benz Center.
Model
Capacity
Fuels, coolants, lubricants, etc.
Engine with oil filter
CLK 320
CLK 500
CLK 55 AMG
8.5 US qt (8.0 l)
8.0 US qt (7.5 l)
9.0 US qt (8.5 l)
Approved engine oils
Automatic transmission
CLK 320
CLK 500
CLK 55 AMG
8.0 US qt (7.5 l)
9.3 US qt (8.7 l)
9.3 US qt (8.7 l)
MB Automatic Transmission Oil
Rear axle
CLK 320
CLK 500
CLK 55 AMG
1.28 US qt (1.2 l)
1.5 US qt (1.4 l)
1.5 US qt (1.4 l)
Hypoid gear oil SAE 85 W 90
Power steering
approx. 1.1 US qt (1.0 l)
MB Power Steering Fluid (Pentosin
CHF 11S)
Front wheel hubs
approx. 3.0 oz (85 g) each
High temperature roller bearing grease
Brake system
0.64 US qt (0.6 l)
MB Brake Fluid (DOT 4+)
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