The Cooling System
The vehicle engine produces a lot of heat when in operation. It, therefore, requires continuous cooling to avoid damage. The cooling process involves circulating a coolant in the engine. The coolant is usually water mixed with antifreeze. In some engine, air is blown over cylinder casting fins.
If you need 5-Star radiator repair shop in Phoenix, call us now for a FREE check-up:
Water cooling system
This system consists of cylinder head and engine block connected with coolant channels. All the system channels converge in one outlet at the top of the cylinder.
The pump pushes coolant from the engine to the radiator. This pump is driven by pulley and belt. Excess heat is transferred from the radiator to a stream of air. It is cooled and then channeled to an inlet at the block bottom before flowing back to the system channels. Rubber hoses are used to link the radiator and the engine. The radiator has a top and a bottom tank which are connected by several tubes.
The tubes pass through thin metallic fins creating a big surface area in the core to allow rapid heat loss to the cool air passing through it. Modern cars have cross flow radiators where the tubes run sideways.
The coolant temperatures stay a little bit under the normal boiling point when the engine is in ordinary temperatures. Increase in pressure raises the boiling point. The extra pressure forces the valve to open allowing the coolant to flow out via an overflow pipe. To avoid the risk of coolant boiling, pressure valves in the radiator cap limit excess pressure.
The cooling water system requires continuous top up as the coolant is gradually lost every time engine runs very hot. Modern vehicles come equipped with a sealed system where the overflow enters an expansion tank. The engine sucks the liquid back when the remaining coolant is cooled.
Function of the Fan
When the car engine is stationary, the fan supplies a constant stream of cool air. The fan is not always required when the car is moving. Some cars have a temperature sensitive valve that triggers the fan when the temperature of the coolant reaches a certain point. Other cars have an electric fan which uses a temperature sensor to switch the fan on and off.
The thermostat closes radiator to allow the engine to warm up faster. When the engine warms up, the valve opens. The coolant flows through the radiator to the engine. The valves close again when the engine cools.
When water freezes, it expands. This means that it can burst the radiator or the engine block. The antifreeze is added to lower the water freezing point to suitable levels.
While water-cooled cooling system is probably the most popular, there is also oil cooling and air-cooled cooling systems.
Read more about your car’s radiator and cooling system: