The cooling system controls the temperature of the vehicle to keep the car overheating. Millions of sparks are created inside the vehicle as it drives down the road creating an obviously high amount of heat, and it is the job to the cooling system to maintain these high temperatures so that the engine will not blow. The cooling system basically consists of cooling liquid being circulated throughout the engine. The fluid then goes to the radiator so that the air coming in the front grill can cool the liquid. No matter the temperature outside, the cooling system must maintain the temperature of the engine at a constant temperature. If the temperature drops too much, fuel economy will drop and emissions rise. The engine will literally self-destruct if the temperature gets too high.
Liquid and air cooled are the two types of cooling systems found within vehicles. The passages inside the engine blocks or heads, a water pump, a radiator, a radiator cap, a thermostat, and plumbing that has interconnecting hoses to transfer coolant from the engine to the radiator make up the cooling system. The water pump circulates the coolant and the thermostat controls the temperature of that coolant. The radiator cools the coolant and the radiator cap is responsible for controlling the pressure within the system.
Liquid coolant is sent through passages inside the blocks and heads of the engine. As the liquid travels through the passages, heat from the engine is picked up. The now heated fluid makes its way, through a tube, to the front of the car where the radiator is located. There it is cooled before it returns to the engine to absorb more heat. The water pump keeps all of the fluid moving.
The cooling system consists of various parts, some harder than others to replace. Typically the hoses will leak if they are busted or need repair, but it is important to get them replaced as soon as possible. If the coolant leaks out of the car, there is nothing to cool the engine. The water pump and radiator can both cause the car to act funny or leak fluid when they bust. If the car is continuously running hot as it is being driven, even right after placing coolant, then one of these two pieces may be broken. They are a bit harder to fix than a hose, but nowhere near as bad as an engine. A professional can tell pretty quickly if there is a leak or bust in the radiator or water pump. The thermostat is simple to replace and easy to find. Typically, when the car is running hot and no problems can be seen, the thermostat is the first part to replace. This can cause the sensor on the car to mess up because the thermostat will read the temperature incorrectly if it is busted.