engine coolant MERCEDES-BENZ CLK350 2006 C209 User Guide

327 Operation
Engine compartment
Coolant
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
compartment.
1Coolant expansion tank
2Cap

Using a rag, turn cap2 slowly
approximately one half turn to the left
to release any excess pressure.

Continue turning the cap2 to the left
and remove it.
The coolant level is correct if the level


for cold coolant: reaches the marking
(plastic bridge) inside the reservoir


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

Add coolant as required.

Replace and tighten cap2.
More information on coolant can be found
in the “Technical data” section
(
page 484).
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 the coolant temperature is
above 158°F (70°C). Allow the coolant
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.

377 Practical hints
What to do if …?
Problem
Possible cause/consequence
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 327).
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.

397 Practical hints
What to do if …?
Display symbol
Display message
Possible cause/consequence
Possible solution
ú
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 327).

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.

398 Practical hintsWhat 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/consequence
Possible solution
•
Coolant
Stop, engine off
The coolant is too hot.

Stop the vehicle in a safe location or
as soon as it is safe to do so and turn
off the engine.

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.

399 Practical hints
What to do if …?
Display symbol
Display message
Possible cause/consequence
Possible solution
•
Coolant
Stop, engine off
The poly-V-belt could be broken.

Stop the vehicle in a safe location or as soon
as it is safe to do so and immediately turn off
the engine.

Check the poly-V-belt.
If it is broken:

Do not continue to drive. Otherwise the en-
gine will overheat due to an inoperative water
pump which may result in damage to the en-
gine. 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.

Drive immediately to the nearest authorized
Mercedes-Benz Center.
Coolant
Visit workshop
The cooling fan for the coolant is mal-
functioning.

Observe the coolant temperature display.

Have the fan replaced as soon as possible.

465 Technical data
Parts service
Warranty coverage
Identification labels
Layout of poly-V-belt drive
Engine
Rims and tires
Electrical system
Main dimensions and weights
Fuels, coolants, lubricants, etc.

479 Technical data
Fuels, coolants, lubricants, etc.
Fuels, coolants, lubricants, etc.
CapacitiesVehicle components and their respective
lubricants must match. Therefore only use
products 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 350
CLK 500
CLK 55 AMG
8.5 US qt (8.0 l)
7.9 US qt (7.5 l)
9.0 US qt (8.5 l)
Approved engine oils
Automatic transmission
CLK 350
CLK 500
CLK 55 AMG
9.0 US qt (8.5 l)
9.0 US qt (8.5 l)
9.3 US qt (8.7 l)
MB Automatic Transmission Fluid
Rear axle
CLK 350
CLK 500
CLK 55 AMG
1.16 US qt (1.1 l)
1.69 US qt (1.6 l)
1.50 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+)

481 Technical data
Fuels, coolants, lubricants, etc.
Engine oils
Engine oils are specifically tested for their
suitability in our engines and durability for
our service intervals. Therefore, only use
approved engine oils and oil filters re-
quired for vehicles with Maintenance
System (U.S. vehicles) or FSS (Canada
vehicles). For a listing of approved engine
oils and oil filters, refer to the Factory Ap-
proved Service Products pamphlet, or
contact an authorized Mercedes-Benz
Center.
Engine oil additives
Do not blend oil additives with engine oil.
They may damage the engine.
Damage or malfunctions resulting from
blending oil additives are not covered by
the Mercedes-Benz Limited Warranty.Air conditioning refrigerant
R-134a (HFC) refrigerant and special PAG
lubricating oil are used in the air
conditioning 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.
Only brake fluid approved by
Mercedes-Benz is recommended. An
authorized Mercedes-Benz Center will
provide you with additional information.
!Using engine oils and oil filters of spec-
ification other than those expressly re-
quired for the Maintenance System
(U.S. vehicles) or FSS (Canada vehi-
cles), or changing of oil and oil filter at
change intervals longer than those
called for by the Maintenance System
(U.S. vehicles) or FSS (Canada vehi-
cles) will result in engine damage not
covered by the Mercedes-Benz Limited
Warranty.
Please follow Maintenance System
(U.S. vehicles) or FSS (Canada vehi-
cles) recommendations for scheduled
oil changes. Failure to do so will result
in engine damage not covered by the
Mercedes-Benz Limited Warranty.
Warning!
G
Under extremely strenuous operating condi-
tions, this moisture content can lead to the
formation of bubbles in the system, thus re-
ducing the system’s efficiency.
Therefore, the brake fluid must be replaced
regularly. Refer to your vehicle's Mainte-
nance Booklet for replacement interval.

482 Technical dataFuels, coolants, lubricants, etc.Premium unleaded gasoline
Fuel requirements
Only use premium unleaded fuel:

The octane number (posted at the
pump) must be 91 min. It is an average
of both the Research (R) octane num-
ber and the Motor (M) octane number:
(R+M) / 2). This is also known as the
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.
Warning!
G
Gasoline is highly flammable and poisonous.
It burns violently and can cause serious
injury. Whenever you are around gasoline,
avoid inhaling fumes and skin contact, extin-
guish all smoking materials. Never allow
sparks, flame or smoking materials near
gasoline!
!To maintain the engine’s durability and
performance, premium unleaded gaso-
line must be used. If premium unleaded
is not available and low octane fuel is
used, follow these precautions:

Have the fuel tank only partially
filled 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 3 000 rpm if the vehicle is loaded
with a light load such as two per-
sons and no luggage.


Do not exceed
2/3 of maximum ac-
celerator pedal position if the vehi-
cle is fully loaded or operating in
mountainous terrain.

483 Technical data
Fuels, coolants, lubricants, etc.
Gasoline additives
A major concern among engine manufac-
turers is carbon build-up caused by gaso-
line. Mercedes-Benz recommends only the
use of quality gasoline containing additives
that prevent the build-up of carbon depos-
its.
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 en-
gine performance problems such as:

Warm-up hesitation


Unstable idle


Knocking/pinging


Misfire


Power lossIn areas where carbon deposits may be en-
countered due to lack of availability of gas-
olines which contain these additives,
Mercedes-Benz recommends the use of
additives approved by us for use on
Mercedes-Benz vehicles. Refer to Factory
Approved Service Products pamphlet for a
listing of approved product(s). Follow di-
rections on 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 addition-
al fuel additives other than those tested
and approved by us for use on
Mercedes-Benz vehicles listed in the
Factory Approved Service Products pam-
phlet are not covered by the
Mercedes-Benz Limited Warranty.