How a Vehicle Cooling System Works

The components of a car's cooling system.

It's been said there's a fine line between love and hate, and when it comes to your engine's relationship with heat, truer words were never spoken.

An internal combustion engine must have heat to run properly and prevent premature wear, but too much heat has the opposite effect, can destroy the engine, or at the very least cause extensive and expensive damage. Responsibility for keeping engine heat at optimal levels falls to the vehicle's cooling system and its components, which in turn depend on preventive maintenance periodically to keep the system and vehicle operating trouble-free.

In a nutshell, the cooling system works by transferring engine heat to the coolant or antifreeze, the coolant moving to the radiator where it loses the excess heat to the outside environment, and the coolant returning to the engine to start the process again. What sounds like a simple process actually depends on several cooling system parts working together flawlessly to keep the engine temperature at an optimal level, regardless of how hot or cold it is outside.

The main components of a car's cooling system include:

• Radiator
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• Coolant/Antifreeze
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• Water pump
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• Thermostat
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• Hoses
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• Radiator fan

How a Vehicle Cooling System Works

RADIATOR

The radiator is a heat exchanger. Sitting at the front of the vehicle, it transfers heat from the vehicle's coolant flowing through it to the outside environment. Most radiators today are constructed of aluminum, but can also be made from plastic, while radiators in older vehicles are predominantly steel because of its strength and durability.

The radiator's design features thin, flat fins connected in a parallel fashion to flat tubes, all of which form a large, honeycombed, square or rectangular-shaped assembly that sits behind the vehicle's front grill. The radiator's exterior should be inspected periodically for an accumulation of bugs or other road debris that could affect its cooling ability, as well as for holes and leaks caused by impacts with stones.