Below are the basic descriptions of both types of common engine cooling systems
What is a cooling system and what does it do?
Fuel is constantly being burned inside your car's engine. Much heat from this combustion goes right out the back end of the cars exhaust system. Some of the heat is absorbed into the engine causing it to heat up. The engine runs at its best when the engine coolant is between 200 to 220 degrees Fahrenheit. At this temperature:- The Engine's combustion chamber is hot enough to completely vaporize the fuel, providing better combustion and reducing emissions.
- The oil used to lubricate the engine has a lower viscosity (it is thinner), so the engine parts move more freely and the engine wastes less power moving its own components around.
- Internal metal parts wear less.
Liquid Cooling
The cooling system on liquid-cooled car engines circulate a fluid through pipes and passageways in the engine. As this liquid passes through the hot engine it absorbs heat, cooling the engine. After the fluid leaves the engine, it passes through a heat exchanger, or radiator, which transfers the heat from the fluid to the air blowing through the exchanger.
Air Cooling
Some older cars, and very few modern cars, are air-cooled. Instead of circulating fluid through the engine, the engine block is covered in aluminum fins that conduct the heat away from the cylinder. A powerful fan forces air over these fins, which cools the engine by transferring the heat to the air.