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Beginner's Guide: What Is the Radiator and What Does It Do?

What is your car's radiator (and what does it do)

A radiator is just one part of a complex cooling system that’s designed to keep a car’s engine operating at just the right temperature.

A radiator is, in essence a heat-exchanger that comprises two water tanks that are linked together by a core made up of myriad narrow tubes.

Hot coolant from the engine is pumped through one tank and then through the core.

As the car travels forward, cold air is forced between these thousands of narrow tubes, and in the process draws the heat out of the coolant.

The cooled fluid is then pumped out of the other end of the radiator and back into the engine.

It travels though numerous channels cut into the engine block and cylinder head, and so cools the structure of the engine, as well as the oil.

What is your car's radiator (and what does it do)

The efficiency of radiators has been enhanced over the years by the addition of thermostatically controlled fans, that force air through the radiator when the car is stationary in hot air.

However, in order to get the maximum throughflow of air when on the move, a radiator is typically mounted at the very front of the car.

This, however, renders is vulnerable to road debris, such as stones, sticks, or even small animals and birds.

Even if impacts with the detritus on the road doesn’t actually puncture the radiator, it can bend the myriad tubes in the radiator’s core, restricting the flow of water through them and adversely affecting the cooling efficiency of the radiator as a whole.

One way to tell if your car’s radiator isn’t working as it should is to simply look at the car’s temperature gauge. If the engine starts to operate at a higher temperature, the radiator could be damaged.

Another way to tell if the radiator is below peak efficiency is if the fan is operating even when the ambient temperature isn’t that hot.