2005 MERCEDES-BENZ SLK CLASS engine

287 Operation
Engine compartment
Engine compartment
Hood
Opening
The hood release is located on the driver
side under the instrument panel.
1Hood lock release lever

Pull hood lock release lever1 in direc-
tion of arrow.
The hood is unlocked.
2Lever for opening the hood

Push lever2 on the hood upward to
release hood.

With the hood released, lift the hood by
lifting it at the front edge.
The hood will be automatically held
open at shoulder height by gas-filled
struts.
Warning!
G
Do not pull the release lever while the vehi-
cle is in motion. Otherwise the hood could
be forced open by passing air flow.
!To avoid damage to the windshield
wipers or hood, never open the hood if
the wiper arms are folded forward away
from the windshield.
Warning!
G
To help prevent personal injury, stay clear of
moving parts when the hood is open and the
engine is running. Make sure the hood is
properly closed before driving. When closing
the hood, use extreme caution not to catch
hands or fingers.
The radiator fan may continue to run for ap-
proximately 30 seconds or even restart af-
ter the engine has been turned off. Stay
clear of fan blades.


288 OperationEngine compartment
Closing
Let the hood drop from a height of
approximately 1 ft (30 cm).
The hood will lock audibly.

Check to make sure the hood is fully
closed.
If you can raise the hood at a point
above the headlamps, then it is not
properly closed. Open it again and let it
drop with somewhat greater force.
Engine oil
The amount of oil your engine needs will
depend on a number of factors, including
driving style. Higher oil consumption can
occur when

the vehicle is new


the vehicle is driven frequently at
higher engine speeds
Engine oil consumption checks should only
be made after the vehicle break-in period.
Warning!
G
If you see flames or smoke coming from the
engine compartment, or if the coolant tem-
perature display in the multifunction display
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 down. If necessary, call the fire
department.Warning!
G
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, diagnos-
tic socket) of the ignition system

with the engine running


while starting the engine


if ignition is “on” and the engine is
turned manually
Warning!
G
Be careful that you do not close the hood on
anyone.
iDo not use any special lubricant addi-
tives, as these may damage the drive
assemblies. Using special additives not
approved by Mercedes-Benz may
cause damage not covered by the
Mercedes-Benz Limited Warranty.
More information on this subject is
available at any authorized
Mercedes-Benz Center.


289 Operation
Engine compartment
Checking engine oil level with the
control system, SLK 55 AMG
When checking the oil level

the vehicle must be parked on level
ground.


with the engine at operating tempera-
ture, the vehicle must have been sta-
tionary for at least five minutes with
the engine turned off.


with the engine not at operating tem-
perature, the vehicle must have been
stationary for at least 30 minutes with
the engine turned off.
To check the engine oil level via the
multifunction display, do the following:

Switch on the ignition (
page 35).
The standard display appears in the
multifunction display (
page 122).

Press buttonk orj on the mul-
tifunction steering wheel repeatedly
until the following message appears in
the multifunction display (
page 118):
One of the following messages will
subsequently appear in the multifunc-
tion display:


Engine oil level
ok


Add 1.0 qt.
(Canada:
1.0 liter
)
to reach max. oil level


Add 1.5 qts.
(Canada:
1.5 liters
)
to reach max. oil level


Add 2.0 qts.
(Canada:
2.0 liters
)
to reach max. oil level

If necessary, add engine oil.
For adding engine oil, see “Adding en-
gine oil” (
page 292).
For more information on engine oil, see
“Fuels, coolants, lubricants, etc.”
(
page 422).iIf you want to interrupt the checking
procedure, press buttonk orj
on the multifunction steering wheel
(page 118).

290 OperationEngine compartmentOther display messages
If the ignition is not switched on, the fol-
lowing message will appear:Turn on ignition
to see engine oil level
Switch on the ignition (
page 35).
If you see the message:
Observe waiting time
If engine is at operating temperature,
wait five minutes before repeating
check procedure.

If engine is not at operating tempera-
ture yet, you must wait 30 minutes
before checking oil.If you see the message:
Engine oil level
Not when engine on
Turn off the engine.

If the engine is at operating tempera-
ture, wait five minutes before checking
oil.

If the engine is not at operating
temperature yet, you must wait
30 minutes before checking oil.If there is excess engine oil with the engine
at normal operating temperature, the
following message will appear:
Engine oil level
Reduce oil level
Have excess oil siphoned or drained
off. Contact an authorized
Mercedes-Benz Center.
For more information on messages in the
display concerning engine oil, see the
“Practical hints” section (
page 348).
iIf you want to interrupt the checking
procedure, press buttonk orj
on the multifunction steering wheel
(page 118).
!Excess oil must be siphoned or drained
off. It could cause damage to the
engine and catalytic converter not
covered by the Mercedes-Benz Limited
Warranty.

291 Operation
Engine compartment
Checking engine oil level with the oil
dipstick, SLK 350
When checking the oil level

the vehicle must be parked on level
ground.


with the engine at operating tempera-
ture, the vehicle must have been sta-
tionary for at least five minutes with
the engine turned off.


with the engine not at operating tem-
perature, the vehicle must have been
stationary for at least 30 minutes with
the engine turned off.1Oil dipstick
2Upper (max) mark
3Lower (min) mark
To check the engine oil level with the oil
dipstick, do the following:

Open the hood (
page 287).

Pull out oil dipstick1.

Wipe oil dipstick1 clean.

Fully insert oil dipstick1 into the
dipstick guide tube.

Pull out oil dipstick1 again after
approximately three seconds to obtain
accurate reading.
The oil level is correct when it is be-
tween the lower (min) mark3 and
upper (max) mark2 of oil dipstick1.

If necessary, add engine oil.
For adding engine oil, see “Adding en-
gine oil” (
page 292).
For more information on engine oil, see
“Fuels, coolants, lubricants, etc.”
(
page 422).
For more information on messages in the
multifunction display concerning engine
oil, see the “Practical hints” section
(page 348).iThe filling quantity between the upper
and lower marks on the oil dipstick is
approximately 2.1 US qt. (2.0 l).

292 OperationEngine compartmentAdding engine oil
Only use approved engine oils and oil fil-
ters required for vehicles with Mainte-
nance System (U.S. vehicles) or FSS
(Canada vehicles). For a listing of approved
engine oils and oil filters, refer to the Fac-
tory Approved Service Products pamphlet
in your vehicle literature portfolio, or con-
tact an authorized Mercedes-Benz Center.
Using engine oils and oil filters of specifica-
tion other than those expressly required
for the Maintenance System (U.S. vehi-
cles) or FSS (Canada vehicles), or changing
of oil and oil filter at change intervals long-
er than those called for by the Mainte-
nance System (U.S. vehicles) or FSS
(Canada vehicles) will result in engine dam-
age not covered by the Mercedes-Benz
Limited Warranty.
SLK 3501Filler capSLK 55 AMG1Filler cap

Unscrew filler cap1 from filler neck.

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.

Screw filler cap1 back on filler neck.
For more information on engine oil, see the
“Technical data” section (
page 422) and
(
page 424).!Excess oil must be siphoned or drained
off. It could cause damage to the
engine and catalytic converter not
covered by the Mercedes-Benz Limited
Warranty.

293 Operation
Engine compartment
Transmission fluid level*
Vehicles with automatic transmission*:
The transmission fluid level does not need
to be checked. If you notice transmission
fluid loss or gear shifting malfunctions,
have an authorized Mercedes-Benz Center
check the transmission.
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.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 approx-
imately ½ 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
glycol which may burn if it comes into
contact with hot engine parts.

294 OperationEngine compartmentThe coolant expansion tank is located on
the passenger side of the engine compart-
ment.SLK 350 (example)1Coolant expansion tank
2Cap
3Marking bar in the expansion tank

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

Continue turning cap2 counterclock-
wise and remove it.
The coolant level is correct if the level

for cold coolant: reaches marking
bar3 in expansion tank1


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

Add coolant as required.

Replace and tighten cap2.
For more information on coolant, see
“Coolants” (
page 426).
Battery
Your vehicle’s battery is located in the en-
gine compartment.
The battery should always be sufficiently
charged in order to achieve its rated ser-
vice life. Refer to the Maintenance Booklet
for battery maintenance intervals.
If you use your vehicle mostly for
short-distance trips, you will need to have
the battery charge checked more frequent-
ly.
When replacing the battery, always use
batteries approved by Mercedes-Benz.
If you do not intend to operate your vehicle
for an extended period of time, consult an
authorized Mercedes-Benz Center about
steps you need to observe.