Mercedes-Benz 2009 C-Class Operator's Manual page 260

Operation
Engine compartment
X
Unscrew filler cap from filler neck.
1
X
Add engine oil as required. Be careful not
to overfill with oil.
Be careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water.
! Excess oil must be siphoned or drained
off. It could cause damage to the engine
and emission control system not covered
by the Mercedes-Benz Limited Warranty.
X
Screw filler cap back on filler neck.
1
For more information on engine oil, see the
"Technical data" section ( Y page 391) and
( Y page 394).
Transmission fluid level
Vehicles with automatic transmission:
The transmission fluid level does not need to
be checked. If you notice transmission fluid
loss or gearshifting malfunctions, have an
authorized Mercedes-Benz Center check the
transmission.
258
Coolant level
The engine coolant is a mixture of water and
anticorrosion/antifreeze.
When checking the coolant level, the vehicle
must be parked on level ground, and the
coolant temperature must be below 158‡
(70†).
G Warning!
In order to avoid any potentially serious
burns:
Use extreme caution when opening the
R
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
R
reservoir if coolant temperature is above
158‡ (70†). 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
R
1
approximately / turn to relieve excess
2
pressure. If opened immediately,
scalding hot fluid and steam will be blown
out under pressure.
Do not spill antifreeze on hot engine
R
parts. Antifreeze contains ethylene
glycol which may burn if it comes into
contact with hot engine parts.
Cap
1
Coolant expansion tank
2
Marking bar in the expansion tank
3
X
Using a rag, turn cap slowly
1
1
approximately / turn counterclockwise
2
to release any excess pressure.
X
Continue turning cap counterclockwise
1
and remove it.