Engine Coolant; Water; Coolant Capacities; Coolant Inhibitors - Clarke C18H Instruction Manual

WARNING
A water and anti-freeze solution is required for
pump installations. Premixing this solution prior to
installing is required. This prevents possible pure
anti-freeze chemical reactions to block heater
elements which can burnout the element. Please see
the I&O section (see Page 5) for proper cooling
system capacities of each model.

3.4.3 Water

Water can produce a corrosive environment in the
cooling system, and the mineral content may permit
scale deposits to form on internal cooling surfaces.
Therefore, inhibitors must be added to control
corrosion, cavitation, and scale deposits.
Chlorides, sulfates, magnesium and calcium are among
the materials which make up dissolved solids that may
cause scale deposits, sludge deposits, corrosion or a
combination of these. Chlorides and/or sulfates tend to
accelerate corrosion, while hardness (percentage of
magnesium and calcium salts broadly classified as
carbonates) causes deposits of scale. Water within the
limits specified in figure #17 is satisfactory as an
engine coolant when properly inhibited.
distilled water is preferred.
Materials
Chloride (Max.)
Sulfates (Max.)
Total Dissolves Solids
(Max.)
Total Hardness (Max.)

3.4.4 Coolant Capacities

Ethylene Glycol or Propylene Glycol are acceptable:
IMPORTANT:
Do not use cooling system sealing additives or
antifreeze that contains sealing additives.
Do not mix ethylene glycol and propylene glycol base
coolants.
Use an ethylene glycol coolant (low silicate
formulation) that meets the standard of ASTM E1177
or propylene glycol that meets ASTM D6210
requirements. Use of propylene glycol requires
Use of
Grains
Milligram per
per Liter Gallon
40 2.4
100 5.9
340 20
170 10
addition of CAT SCA (Supplemental Coolant
Additive) to prevent liner cavitation.
A 50% coolant water solution is recommended. A
concentration over 70% is not recommended because
of poor heat transfer capability, adverse freeze
protection and possible silicate dropout.
Concentrations below 30% offer little freeze, boil over
or corrosion protection.
IMPORTANT
Never use automotive-type coolants (such as those
meeting only ASTM D3306 or ASTM D4656).
These coolants do not contain the correct additives
to protect heavy-duty diesel engines. They often
contain a high concentration of silicates and may
damage the engine or cooling system.
ENGINE
MODEL
C18H-All Models

3.4.5 Coolant Inhibitors

The importance of a properly inhibited coolant cannot
be over-emphasized. A coolant which has insufficient
or no inhibitors at all, invites the formation of rust,
scale, sludge and mineral deposits. These deposits can
greatly reduce the cooling systems efficiency and
protection capabilities.
Recommended supplemental coolant inhibitors are a
combination of chemical compounds which provide
corrosion protection, cavitation suppression, pH
controls and prevents scale. These inhibitors are
available in various forms, such as liquid packages or
integral parts of an extended life coolant.
It is imperative that inhibitors are used in all Caterpillar
engine cooling systems. A pre-charge dosage must be
used at the initial fill with a conventional coolant, that
is not fully formulated, and the maintenance dosage
must be added at each service interval. Conventional
coolants must meet ASTM D4985 or ASTM D6210 to
be used in Cat engines. Conventional coolants rely on
inorganic inhibitors and are (re)charged with a
Supplemental Coolant Additive (SCA)
An extended life coolant that meets ASTM D4985 or
ASTM D6210 and contains less than 125 ppm of
silicon (present as silicate) can be used in Cat engines
to the recommended maximum service life. Extended
life coolants rely on organic inhibitors and are
recharged with an Extender. Extenders are typically
added at one half the service life of the coolant.
36
COOLANT
CAPACITY
QUARTS (LITERS)
40 (37.9)