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heat to convection and radiation from these parts to the
environment is insufficient.
Insufficient level of heat output causes deterioration of
friction, burn-out and overheating of the engine. The latter
leads to a sharp drop in the strength of the material and its
overheating (for example, exhaust valves, bottoms of pistons).
In case of severe overheating of the engine, normal gaps
between the parts are broken, which leads to increased wear,
clogging and breakage of these parts. Overheating of the engine
is harmful also because of the deterioration of the filling of
cylinders with fresh charge, and in carburetors, in addition, it is
possible detonation combustion or detonating ignition of the
working mixture.
To intensify heat removal from the hottest parts, forced
cooling is required. A set of special devices that perform such a
task form a cooling system.
Excessive cooling of the engine is also undesirable
because it causes condensation of fuel particles on the walls of
the cylinders, the deterioration of the mixture formation and
ignition of the working mixture, increased frictional losses,
accelerated wear of engine parts and, as a result, a drop in
power and a deterioration in engine efficiency.
Consequently, the cooling system should provide
support for the most favorable thermal state of engine parts in
all modes of its operation.
Depending on the kind of coolant that selects heat from
the hottest engine parts, distinguish liquid, air and evaporative
cooling systems. By the multiplicity of use of the coolant
cooling system is divided into flow and circulating. By way of
circulating the liquid cooling system, they are divided into
thermosyphon and coercive. The most common liquid cooling
systems with forced circulation. When studying the engine
cooling system, it is first of all to establish the type of system,

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