engine coolant MERCEDES-BENZ SLK ROADSTER 2008 User Guide

Service products and capacities
259Coolant
The coolant is a mixture of water and anti-
freeze/corrosion inhibitor. It performs the
following tasks:
R anti-corrosion protection
R antifreeze protection
R raising the boiling point
i When the vehicle is first delivered, it is
topped up with a coolant that will ensure
adequate antifreeze and corrosion protec -
tion.
! Only top up with coolant that has been
premixed with the desired quantity of anti -
freeze protection. You could otherwise
damage the engine.
There is more information about coolant
and topping it up on Mercedes-Benz Spec-
ifications for Service Products Sheet
310.1.
! Always use a suitable coolant mixture,
even in countries where high temperatures
prevail.
Otherwise, the cooling system will not be
sufficiently protected from corrosion, and
the boiling point will be too low .If antifreeze/corrosion inhibitor is present in
the correct concentration, the boiling point of
the coolant will be around 130 °C.
The antifreeze/corrosion inhibitor concentra-
tion in the cooling system should:
R
be at least 50%. This will protect the coolin g
system against freezing down to around –
37 °C.
R not exceed 55% concentration (antifreeze
protection down to –45 °C), otherwise hea t
will not be effectively dissipated .
If the vehicle has lost coolant, top it up with
equal amounts of water and antifreeze/cor-
rosion inhibitor. Mercedes-Benz recom-
mends using an antifreeze/corrosion inhibi -
tor which has been approved for Mercedes-
Benz.
! The cooling system contains a lifetime
supply which must be renewed after 15
years, or after 250, 000 km at the latest.
Have the renewal confirmed in the Service
Booklet.
The warranty is only valid if you top up with
an antifreeze/corrosion inhibitor which
has been approved by Mercedes-Benz. Technical data
171_AKB; 3; 4, en-G
B
vpfaff7, 2007-11-13T10:50:25+01:00 - Seite 259

Service products and capacities
260
Capacities The following values indicate the total cooling system capacities.
SLK 200 KOMPRESSOR SLK 280 SLK 350 SLK 55 AMG
Coolant 8.2
l 9.8
l 9.8
l 11.1
l Amount of antifreeze/corrosion inhibitor required for antifreeze protection
Down to –37 °C
(approximately 50%) 4.1
l 4.9
l 4.9
l 5.55
l Down to –45 °C
(approximately 55%) 4.5
l 5.4
l 5.4
l 6.1
l Brake fluid
Over a period of time, the brake fluid absorbs
moisture from the air; this lowers its boiling
point. G
Risk of accident
If the boiling point of the brake fluid is too
low, vapour pockets may form in the brake
system when the brakes are applied hard
(e.g. when driving downhill). This woul d
impair braking efficiency.
Have the brake fluid renewed every two
years with a brake fluid that has been approved by Mercedes-Benz and have this
confirmed in the Service Booklet.
i There is usually a notice in the engine
compartment to remind you when the next
brake fluid change is due. Windscreen washer system
The washer fluid reservoir holds approxi-
mately 7 litres.
The headlamp cleaning system* and the
windscreen washer system are both supplied
from the washer fluid reservoir.
X At temperatures above freezing point:
Top up the washer fluid reservoir with a
mixture of water and windscreen washer
concentrate (Y page 154).
X At temperatures below freezing point:
Top up the washer fluid reservoir with a
mixture of water, antifreeze and wind-
screen washer concentrate (Y page 154). Technical data
* optional
171_AKB; 3; 4, en-GB
vpfaff7,
2007-11-13T10:50:25+01:00 - Seite 260