A car radiator is an important component of a car's cooling system. It transfers heat away from the engine and helps keep the engine running at its optimal temperature. The radiator also helps prevent the engine from overheating. It does this by allowing the heated coolant to flow through the radiator, where it is cooled by air passing through the radiator's cooling fins. Once the coolant is cooled, it is recirculated back to the engine to be reheated and the cycle continues. A car radiator also helps to protect the engine from damage caused by extreme temperatures.