Mercedes-Benz SLR McLaren. Operator's Manual.

Coolants
The engine coolant is a mixture of water
and anticorrosion/antifreeze, which provides:
corrosion protection
freeze protection
boiling protection (by increasing the
boiling point)
The cooling system was filled at the factory
with a coolant providing freeze protection
to approximately -22°F (-30°C) and corrosion
protection.
If the antifreeze mixture is effective to
-22°F (-30°C), the boiling point of the coolant
in the pressurized cooling system is
reached at approximately 266°F (130°C).
The coolant solution must be used year
round to provide the necessary corrosion
protection and increase in the boil-over
protection. Refer to Maintenance Booklet
for replacement interval.
Coolant system design and coolant used
determine the replacement interval. The
replacement interval published in the
Maintenance Booklet is only applicable if
MB 325.0 anticorrosion/antifreeze solution
or other Mercedes-Benz approved
products of equal specification (see
Factory Approved Service Products pamphlet)
are used to renew the coolant concentration
or bring it back up to the proper
level.
To provide important corrosion protection,
the solution must be at least 45% anticorrosion/antifreeze
(equivalent to freeze
protection to approximately
- 22°F [-30°C]). If you use a solution that is
more than 55% anticorrosion/antifreeze
(freeze protection to approximately
- 49°F [-45°C]), the engine temperature
will increase due to the lower heat transfer
capability of the solution. Therefore, do not
use more than this amount of anticorrosion/antifreeze.
Technical data
Fuels, coolants, lubricants, etc.
If the coolant level is low, water and
MB 325.0 anticorrosion/antifreeze should
be used to bring it up to the proper level
(have cooling system checked for signs of
leakage). Please make sure the mixture is
in accordance with label instructions.
The water in the cooling system must meet
minimum requirements, which are usually
satisfied by normal drinking water. If you
are not sure about the water quality, consult
an authorized Mercedes-Benz Center.
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