MERCEDES-BENZ CLK350 COUPE 2007 C209 Owner's Manual

310 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
2CapUsing a rag, turn cap 2 slowly
approximately one half turn counter-
clockwise to release any excess pres-
sure.
Continue turning the cap 2 counter-
clockwise 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 cap 2.
More information on coolant can be found
in the “Technical data” section
(
page 453).
Warning!G
In order to avoid any potentially 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 indicator
indicates 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.

311 Operation
Engine compartment
Battery
Your vehicle’s battery is located in the
engine compartment on the right-hand
side (
page 421).
The battery should always be sufficiently
charged in order to achieve its rated
service life. Refer to 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
frequently.
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.Batteries contain materials that can harm
the environment if disposed of improperly.
Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.
Warning!G
Observe all safety instructions and precau-
tions when handling automotive batteries.
Risk of explosion.
Fire, open flames and smoking
are prohibited when handling
batteries. Avoid creating sparks.
Battery acid is caustic. Do not
allow it to come into contact
with skin, eyes or clothing.
Wear suitable protective cloth-
ing, especially gloves, apron and
faceguard.
Wear eye protection.
Rinse any acid spills immediate-
ly with clear water. Contact a
physician if necessary.
Keep children away.
Follow the instructions in this
Operator’s Manual.

312 Operation
Engine compartment
Windshield washer system and
headlamp cleaning system*
The windshield washer reservoir is located
in the engine compartment.
1Washer fluid reservoir cap
Fluid for the windshield washer system and
the headlamp cleaning system* is supplied
from the windshield washer reservoir. It
has a capacity of approx. 6.4 US qt (6 l).
During all seasons, add MB Windshield
Washer Concentrate “MB SummerFit” to
water. Premix the windshield washer fluid
in a suitable container.
Refill the reservoir with MB Windshield
Washer Concentrate “MB SummerFit”
and water (or commercially available
premixed windshield washer
solvent / antifreeze, depending on am-
bient temperatures).For more information, see “Windshield
washer system and headlamp cleaning
system*” (
page 455).
Warning!G
Washer solvent/antifreeze is highly flam-
mable. Do not spill washer
solvent/antifreeze on hot engine parts,
because it may ignite and burn. You could be
seriously burned.
!Always use washer solvent/antifreeze
where temperatures may fall below the freezing
point. Failure to do so could result in damage to
the washer system/reservoir.
!Only use washer fluid which is suitable for
plastic lenses. Improper washer fluid can dam-
age the plastic lenses of the headlamps.

313 Operation
Tires and wheels
Tires and wheels
See an authorized Mercedes-Benz Center
for information on tested and
recommended rims and tires for summer
and winter operation. They can also offer
advice concerning tire service and
purchase.Important guidelines

Only use sets of tires and rims of the
same type and make.

Tires must be of the correct size for the
rim.

Break in new tires for approximately
60 miles (100 km) at moderate
speeds.

Regularly check the tires and rims for
damage. Dented or bent rims can
cause tire inflation pressure loss and
damage to the tire beads.

If vehicle is heavily loaded, check tire
inflation pressure and correct as
required.

Do not allow your tires to wear down
too far. Adhesion properties on wet
roads are sharply reduced at tread
depths under
1/8in (3 mm).

When replacing individual tires, you
should mount new tires on the front
wheels first (on vehicles with
same-sized wheels all around).
Warning!G
Replace rims or tires with the same designa-
tion, manufacturer and type as shown on the
original part. See an authorized
Mercedes-Benz Center for further informa-
tion. If incorrectly sized rims and tires are
mounted:

The wheel brakes or suspension
components can be damaged.

The operating clearance of the wheels
and the tires may no longer be correct.
Warning!G
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
When replacing rims, only use Genuine
Mercedes-Benz wheel bolts specified for the
particular rim type. Failure to do so can
result in the bolts loosening and possibly an
accident.
Retreaded tires are not tested or recom-
mended by Mercedes-Benz, since previous
damage cannot always be recognized on re-
treads. The operating safety of the vehicle
cannot be assured when such tires are used.

314 Operation
Tires and wheels
Tire care and maintenance
Regularly check your tire inflation pressure
at least once a month. For more informa-
tion on checking tire inflation pressure see
“Recommended tire inflation pressure”
(
page 321).Tire inspection
Every time you check your tire inflation
pressure, you should also inspect your
tires for the following:

excessive treadwear (page 315)

cord or fabric showing through the
tire’s rubber

bumps, bulges, cuts, cracks or splits in
the tread or side of the tire
Replace the tire if you find any of the above
conditions.
Make sure you also inspect the spare tire
periodically for condition and inflation.
Spare tires will age and become worn over
time even if never used, and thus should be
inspected and replaced when necessary.Life of tire
The service life of a tire is dependent upon
varying factors including but not limited to:

Driving style

Tire inflation pressure

Distance driven
Warning!G
Regularly check the tires for damage. Dam-
aged tires can cause tire inflation pressure
loss. As a result, you could lose control of
your vehicle.
Worn, old tires can cause accidents. If the
tire tread is badly worn, or if the tires have
sustained damage, replace them.
Warning!G
Tires and spare tire should be replaced after
6 years, regardless of the remaining tread.

315 Operation
Tires and wheels
Tread depth
Do not allow your tires to wear down too
far. Adhesion properties on wet roads are
sharply reduced at tread depths under
1/8in (3 mm).
Treadwear indicators (TWI) are required by
law. These indicators are located in six
places on the tread circumference and
become visible at a tread depth of approx-
imately
1/16in (1.6 mm), at which point the
tire is considered worn and should be re-
placed.
Recommended minimum tire tread depth:

Summer tires 1/8in (3 mm)

Winter tires 1/6in (4 mm)
1TWI (T
readWear Indicator)
The treadwear indicator appears as a solid
band across the tread.Storing tires
Cleaning tiresWarning!G
Although the applicable federal motor safety
laws consider a tire to be worn when the
treadwear indicators (TWI) become visible at
approximately
1/16in (1.6 mm), we recom-
mend that you do not allow your tires
to wear down to that level. As tread depth
approaches 1/8in (3 mm), the adhesion
properties on a wet road are sharply re-
duced.
Depending upon the weather and/or road
surface (conditions), the tire traction varies
widely.!Keep unmounted tires in a cool, dry place
with as little exposure to light as possible. Pro-
tect tires from contact with oil, grease and gaso-
line.
!Never use a round nozzle to power wash
tires. The intense jet of water can result in dam-
age to the tire.
Always replace a damaged tire.

316 Operation
Tires and wheels
Direction of rotation
Unidirectional tires offer added advan-
tages, such as better hydroplaning perfor-
mance. To benefit, however, you must
make sure the tires rotate in the direction
specified.
An arrow on the sidewall indicates the
intended direction of rotation (spinning) of
the tire.Loading the vehicle
A label on your vehicle shows how much
weight it may properly carry.

The Tire and Loading Information
placard can be found on the driver’s
door B-pillar. This placard tells you im-
portant information about the number
of people that can be in the vehicle and
the total weight that can be carried in
the vehicle. It also contains information
on the proper size and recommended
tire inflation pressures for the original
equipment tires on your vehicle.

The certification label found on the
driver’s door B-pillar tells you about the
gross weight capacity of your vehicle,
called the Gross Vehicle Weight Rating
(GVWR). The GVWR includes the weight
of the vehicle, all occupants, fuel and
cargo. The certification label also tells
you about the front and rear axle
weight capacity, called the Gross Axle
Weight Rating (GAWR). The GAWR is
the total allowable weight that can be carried by a single axle (front or rear).
Never exceed the GVWR or GAWR for
either the front axle or rear axle.
1Driver’s door B-pillar
Following is a discussion on how to work
with the information contained on the plac-
ard with regards to loading your vehicle.
iSpare wheels may be mounted against the
direction of rotation (spinning) even with a unidi-
rectional tire for temporary use only until the reg-
ular drive wheel has been repaired or replaced.
Always observe and follow applicable temporary
use restrictions and speed limitations indicated
on the spare wheel.

317 Operation
Tires and wheels
Tire and Loading InformationTire and Loading Information placard
1Load limit information on the Tire and
Loading Information placard
The placard showing the load limit informa-
tion is located on the driver’s door B-pillar.
Locate the statement “The combined
weight of occupants and cargo should
never exceed XXX kilograms or XXX
lbs.” on this placard.
The combined weight of all occupants,
cargo / luggage and trailer tongue load
(if applicable) should never exceed the
weight referenced in that statement.Seating capacity
The seating capacity gives you important
information on the number of occupants
that can be in the vehicle. Observe front
and rear seating capacity. The placard
showing the seating capacity is located on
the driver’s door B-pillar (
page 316).
1Seating capacity information on the
Tire and Loading Information placard.
Warning!G
Do not overload the tires by exceeding the
specified load limit as indicated on the plac-
ard on the driver’s door B-pillar. Overloading
the tires can overheat them, possibly caus-
ing a blowout. Overloading the tires can also
result in handling or steering problems, or
brake failure.
iData shown on placard example are for
illustration purposes only. Load limit data are
specific to each vehicle and may vary from data
shown in the illustration below. Refer to placard
on vehicle for actual data specific to your
vehicle.
iData shown on placard example are for
illustration purposes only. Seating data are
specific to each vehicle and may vary from data
shown in the illustration below. Refer to placard
on vehicle for actual data specific to your
vehicle.

318 Operation
Tires and wheels
Steps for determining correct load limit
The following steps have been developed
as required of all manufacturers under Title
49, Code of U.S. Federal Regulations, Part
575 pursuant to the “National Traffic and
Motor Vehicle Safety Act of 1966”.
Step 1
Locate the statement “The combined
weight of occupants and cargo should
never exceed XXX kg or XXX lbs.” on
your vehicle’s placard.Step 2
Determine the combined weight of the
driver and passengers that will be
riding in your vehicle.
Step 3
Subtract the combined weight of the
driver and passengers from XXX kilo-
grams or XXX lbs.
Step 4
The resulting figure equals the avail-
able amount of cargo and luggage load
capacity. For example, if the “XXX”
amount equals 1400 lbs. and there will
be five 150 lbs. passengers in your
vehicle, the amount of available cargo
and luggage load capacity is 650 lbs.
(1400-750 (5 x150) = 650 lbs.)
Step 5
Determine the combined weight of
luggage and cargo being loaded on the
vehicle. That weight may not safely
exceed the available cargo and luggage
load capacity calculated in step 4.Step 6 (if applicable)
If your vehicle will be towing a trailer,
load from your trailer will be trans-
ferred to your vehicle. Consult this
manual to determine how this reduces
the available cargo and luggage load
capacity of your vehicle (
page 320).
The following table shows examples on
how to calculate total and cargo load
capacities with varying seating configura-
tions and number and size of occupants.
The following examples use a load limit
of 1500 lbs. This is for illustration
purposes only. Make sure you are using
the actual load limit for your vehicle stated
on the vehicle’s placard (
page 317).

319 Operation
Tires and wheels
The higher the weight of all occupants, the
less cargo and luggage load capacity is
available.
For more information, see “Trailer tongue
load” (
page 320).
ExampleCombined
weight limit
of occu-
pants and
cargo from
placardNumber of
occupants
(driver and
passengers)Seating
configura-
tionOccupants weight Combined
weight of all
occupantsAvailable cargo/luggage and trailer
tongue weight (total load limit
weight from placard minus com-
bined weight of all occupants)
11500 lbs4front: 2
rear: 2Occupant 1: 150 lbs
Occupant 2: 180 lbs
Occupant 3: 160 lbs
Occupant 4: 140 lbs630 lbs1500 lbs - 630 lbs = 870 lbs
21500 lbs3front: 1
rear: 2Occupant 1: 200 lbs
Occupant 2: 190 lbs
Occupant 3: 150 lbs540 lbs1500 lbs - 540 lbs = 960 lbs
31500 lbs1front:1Occupant 1: 150 lbs150 lbs1500 lbs - 150 lbs = 1350 lbs