Cooling System - Volkswagen Marine SDI Series Operating Manual

Cooling system

The cooling system must be filled with a
mixture of water and a 33 % share of our
coolant additive G 12 A8C (glycol-based
antifreeze with corrosion inhibitors).
This mixture not only offers the necessary
frost protection down to -25 OC, it also
primarily protects the alloy parts in the cool-
ing system against corrosion. In addition, it
prevents lime deposits and considerably
increases the coolant boiling point.
For these reasons, you should never dilute
the coolant by topping it up with pure water,
even during the summer months or in warm
climates. The percentage of coolant
additive must be at least 33 %.
If for climatic reasons greater frost protec-
tion is required, the percentage of G 12 A8D
can be increased, however only up to 60%
(frost protection down to approximately
o
-40 C), as otherwise the front protection is
decreased again and the cooling effect
worsens.
Coolant loss
The primary cause of coolant loss is system
leakage. In this case the cooling system
should be checked immediately by a VW
Marine Service Partner. Simply continuing
to top up the system will not solve the un-
derlying problem.
A leak-free system may also discharge a
certain amount of coolant through the
discharge tube in response to high engine
temperatures.
INSPECTION
Coolant additive
Only G 12 A8D coolant additive
(antifreeze on glycol basis with
corrosion protection additives) or an
additive with
TL-VW 774 D (see container label)
may be used. The coolant additive is
available from VW Marine Service
Partners.
Other coolant additives can lead to
serious reductions in the coolant's
ability to inhibit corrosion.
The ultimate result could assume
the form of coolant loss and sub-
stantial engine damage.
Important
The antifreeze additive and the
coolant are
hazards!
Always store
antifreeze additive in original
containers only, being sure to
keep them well beyond the reach
of children.
necessary to discharge coolant
from the system for any reason,
drain it into a container and store
it in a safe place.
Drained coolant should normally
not be reused;
disposed of under observance of the
applicable environmental protec-
tion regulations.
INSPECTION
the specification
potential health
coolant and
Should it
it must
45
be
be
45