The purpose of the cooling system is to maintain the most
efficient operating temperature of an engine without causing
damage to the components. Approximately 1/3 of the energy
produced when fuel burns is converted into power by the
engine. The other 2/3 of the energy must be disposed of by
the exhaust system and the cooling system or engine damage
Basically, the circulation of coolant through the cooling system
relies upon the water pump. The water pump draws coolant
from the radiator and forces it through the water jackets and
cylinder heads, where it accumulates heat. The coolant then
flows to the upper radiator tank and down through the radiator
where it is cooled by air drawn through the radiator fins.
The damages or effects caused by cooling system neglect are
usually gradual and are therefore often overlooked. This
manual provides the reader with basic component knowledge,
maintenance procedures, service intervals, trouble-shooting
and coolant and inhibitor recommendations.
The selection and maintenance of the engine coolant is as
important to long engine life as the selection and changing of
the engine lubricating oil and oil filters. The following section
provides IHs recommendations for selecting the engine
coolant and maintenance of the coolant inhibitors.
IH engines will operate successfully with a water/antifreeze
mixture or inhibited water as the coolant. Never use water
alone as it allows rust, scale deposits and corrosion to occur
within the engine.
Water used in the cooling system must meet the following
Total Hardness not to exceed 170 parts per million
deposits. Water containing dissolved magnesium
and calcium (the usual reason for water hardness)
above the specified amount will cause scale deposits
to develop in the engine.
Chlorides not to exceed 40 parts per million (2.5
grains/gallon maximum) to prevent corrosion.
Sulfates not to exceed 100 parts per million (5.8
grains/gallon maximum) to prevent corrosion.
Dissolved Solids not to exceed 340 parts per million
(20 grains/gallon maximum) to minimize sludge
deposits, scale deposits, corrosion or a combination
If any of the above requirements cannot be met, use distilled,
de-ionized or de-mineralized water. Water samples can be
tested by water treatment laboratories to determine if local
water supplies meet these standards. "Softened" water that is
prepared using common salt (sodium chloride) contains
excessive amounts of chlorides which will interfere with the
water softening capabilities of coolant filters using ion-
IH Anti-Freeze and Coolant contains all necessary inhibitors
and has been tested for use in IH products. It is an ethylene
glycol type anti-freeze and compatible with chromate and non-
chromate type coolant filters.
Several factors should be considered for successful operation
when using ethylene glycol type anti-freezes.
The boiling point of ethylene glycol anti-freeze
solutions is higher than plain water but their ability to
transfer heat is less. Therefore in hot weather,
coolant temperatures will run higher than systems
containing plain water. This also holds true for
temperatures where oil to water coolers are used.
An anti-freeze concentration greater than 68% will
adversely affect freeze protection and heat transfer
rates. Anti-freeze concentrations between 68 and
100% actually have a higher freezing point than a
68% anti-freeze concentration. Due to the higher
freezing point and reduced heat transfer rates,
concentrations greater than 68% should not be used.
It is also important to remember that anti-freeze may
retain its freeze protection for more than one season
but coolant conditioners must be added to maintain
corrosion protection. Figure 1 illustrates the freezing
point of anti-freeze according to its percentage of
Anti-freeze containing sealer or anti-leak additives
should not be used in IH engines. These additives
may cause plugging problems in the cooling system
and restrict coolant flow.
Anti-freeze formulated with methoxy propanol or
propolene glycol is not recommended for use in IH
engines, due to a reaction with engine internal seals,
coolant hoses and potential fire hazard due to lower
flash points than ethylene glycol type antifreeze.
The use of methanol alcohol or methoxy propanol
(Dowtherm 209) based anti-freeze may result in
separation of the anti-freeze and water.
Coolant Conditioners All cooling system inhibitors, including
those in antifreeze solutions, become depleted through normal
operation. If the inhibitors in anti-freeze are allowed to
become depleted, the anti-freeze becomes corrosive