Coolants - Mercedes-Benz 240 D 1979 Owner's Manual

Fuels

Coolants

Lubricants etc.
Coolants
The coolant is a m ixture o f w ater
and antifreeze. In production, the
cooling system is filled w ith an anti-
freeze-water m ixture offering pro­
tection to approx. —22° F
( — 30° C). The red mark on the
tem perature gauge in the instru­
m ent cluster is m atched to this
antifreeze-water m ixture (approx.
boiling point 257° F/125° C). The
protection against corrosion is also
ensured by this m ixture making it
unnecessary to add a corrosion
inhibitor.
The coolant remains in the cooling
system all year round and m ust be
renewed after 2 years at the latest.
This applies also to trailer opera­
tion, hard driving and to vehicles
driven in tropical countries.
If coolant has leaked from the co ol­
ing system, replace the missing
quantity w ith w ater and a recom ­
mended brand o f antifreeze.
For normal replenishment (due to
evaporation o f water) plain w ater
w ill do.
86
The w ater should be clean, so ft to
m edium soft and contain the m ini­
m um am ount o f scale form ing
minerals (potable w ater quality).
The coolant m ixture should always
contain enough antifreeze to ensure
protection to a m inim um o f —4° F
( - 2 0 ° C).
If antifreeze is not available, add a
corrosion inhibitor to the cooling
w ater to ensure proper protection
against corrosion. To treat the cool­
ing w ater, do not use more than
1 % (10 cc cm /l) o f a recommended
corrosion inhibitor.
W ith o u t antifreeze in the cooling
system, the w ater already starts
boiling at approx. 224° F (118° C),
w hich means th a t the pointer o f the
tem perature gauge in the instru­
m ent cluster may still be below the
red mark.
A n tifre eze
Prior to the onset o f the cold
season, check the coolant fo r its
resistance to cold. Repeat this
check during the cold spell.
Regular testing o f the antifreeze
concentration is carried o ut only at
each MERCEDES-BENZ m ain­
tenance service.
To prevent damage to the cooling
system, fill only w ith recom ­
mended brands o f antifreeze.
A ny MERCEDES-BENZ service
station w ill readily advise you on
recommended antifreeze brands.
300 D
240 D 300 CD
Protection Antifreeze
up to U S /Im p. qts. (liter)
- 4 ° F 3.7/3.1 3.7/3.3
- 2 0 ° C) (3.5 I) (3.75 I)
- 2 2 ° F 5.3/4.4
4.7/3.9
- 3 0 ° C) (5.0 I)
(4.5 I)
- 4 0 ° F
5.5/4.6 6/5.1
- 4 0 ° C)
(5.25 I) (5.75 I)