2005 MERCEDES-BENZ C320 engine coolant

283 Operation
Engine compartment
Coolant level
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
2Cap

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

Continue turning the cap to the left and
remove it.
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.
For more information on coolant, see
“Coolants” (
page 394).
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 coolant temperature is
above 158°F (70°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
approximately
1/2 turn to relieve excess
pressure. If opened immediately, scald-
ing 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.

316 Practical hintsWhat to do if …Display symbol
Display message
Possible cause
Possible solution
B
Coolant
Check level
The coolant level is too low.

Add coolant (
page 283).

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
engine damage.

317 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
•
Coolant
Stop, engine off!
The coolant is too hot.

Stop the vehicle and turn off the
engine.

Only start the engine again after the
message disappears. You could
otherwise damage the engine.
Warning!
G
Driving when your engine is badly over-
heated 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.

318 Practical hintsWhat to do if …Display symbol
Display message
Possible cause
Possible solution
•
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 inoperative
water pump which may result 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.

Observe the coolant temperature gauge in
the instrument cluster (
page 24).

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

Observe the coolant temperature gauge in
the instrument cluster (
page 24).

Have the fan replaced as soon as possible.

373 Technical data
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

387 Technical data
Fuels, coolants, lubricants, etc.
Fuels, coolants, lubricants, etc.
Capacities
Vehicle components and their respectivelubricants must match. Therefore only use
brands tested and approved by
Mercedes-Benz. Please refer to the Factory Approved
Service Products pamphlet, or inquire at
your Mercedes-Benz Center.
Model
Capacity
Fuels, coolants, lubricants, etc.
Engine with oil filter
C 230 Kompressor (all models)
C240
C2404MATIC
C320
C3204MATIC
C320Sport
C55AMG
5.8 US qt (5.5 l)
7.9 US qt (7.5 l)
7.4 US qt (7.0 l)
7.9 US qt (7.5 l)
7.4 US qt (7.0 l)
7.9 US qt (7.5 l)
9.0 US qt (8.5 l)
Approved engine oils
Automatic transmission
C 230 Kompressor (all models)
C240 (all models)
C320 (all models)
C55AMG
8.5 US qt (8.0 l)
8.5 US qt (8.0 l)
8.5 US qt (8.0 l)
9.3 US qt (8.7 l)
MB Automatic Transmission Fluid
Manual transmission
1.3 US qt (1.2 l)
MB Manual Transmission Oil
Rear axle
C 230 Kompressor (all models)
C240 (all models)
C320 (all models)
C55AMG
1.2 US qt (1.1 l)
1.2 US qt (1.1 l)
1.2 US qt (1.1 l)
1.5 US qt (1.4 l)
Hypoid gear oil SAE 85 W 90

390 Technical dataFuels, 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
required 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
Approved Service Products pamphlet, or
contact an authorized Mercedes-Benz
Center.
Using engine oils and oil filters of
specification other than those expressly
required for the Maintenance System
(U.S. vehicles) or FSS (Canada vehicles), 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 Vehicles) will result in engine
damage not covered by the
Mercedes-Benz Limited Warranty.Please follow Maintenance System
(U.S. vehicles) or FSS (Canada vehicles)
recommendations for scheduled oil
changes. Failure to do so will 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 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 is 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. Under extremely strenu-
ous operating conditions, this moisture
content can lead to the formation of
bubbles in the system, thus reducing the
system’s efficiency.
Therefore, the brake fluid must be
replaced every two years, preferably in the
spring.
Only brake fluid approved by
Mercedes-Benz is recommended. Your
authorized Mercedes-Benz Center will
provide you with additional information.

391 Technical data
Fuels, coolants, lubricants, etc.
Premium unleaded gasoline
Fuel requirements
Only use premium unleaded fuel:

The octane number (posted at the
p um p) m us t be 91 mi n. It i s an a vera ge
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 must not 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.
!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
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.
iFlexible Fuel Vehicles (identified by a
label reading Premium gasoline or
E85 only! are designed to operate on
premium unleaded gasoline or Ethanol
fuel (E85) or any mixture of these two.
For more information, see “Flexible
Fuel Vehicles” (
page 392).