A car engine burns fuel and uses friction to give your car motion. These processes cause a great amount of heat to build up in the engine. If this heat is not diverted away from the engine, it can cause the pistons in the engine to seize up in their cylinders and eventually snap; causing engine break down.
Some of the heat escapes through the exhaust system. Oil is used to lubricate the internal engine parts and cut down on the friction. But oil and the exhaust system by themselves are not enough to get rid of the excess heat. A car engine runs best at an average of 180 degrees F. Once the temperature reaches 200 degrees F, the cooling system has to kick in and help to cool the engine.
Near the front of the engine there is a thermostat. As the engine heats up and reaches a certain temperature, the thermostat opens to allow the flow of coolant and water. The water/coolant combination is held in the radiator. As it comes into the engine, it is sent around the cylinders to pick up the heat from the friction and burning fuel. The coolant is then sent back into the radiator where it goes into small chambers that are all throughout the radiator.
The surface area of the radiator alone is enough to cool down the coolant. However, a fan between the engine and radiator helps to cool it down even more. Further cooling is done through the grill of the moving car as the air from outside the car blows onto the radiator. Once the coolant has made the trip through the radiator it's ready to go back to the engine and pick up more heat.
There are many reasons for a radiator to stop working. One reason is the thermostat may get clogged and not open. If this happens the coolant cannot get through and the radiator can overheat. As a result, your engine can seize up.
However, the most common reason for a breakdown in a cooling system is a leak. There are many seals, gaskets and hoses that can deteriorate or get a hole in them and leak. As the coolant gets low it will not be able to cool properly and the engine will overheat. If this happens, turn the engine off and allow it to cool down before taking it to a repair shop.
