Function of Radiator for Cars
The engine of automobiles always heats up every time when the explosion occurs in high temperature. Therefore, it is necessary to cool it down to a suitable temperature like between 80 and 100 degrees Celsius when an explosion runs for a long time successively in the engine. The radiator works for cooling down the engine to these temperature zone. Most of engines are water-cooled in general except some air-cooled and electric cars such as classic Porsche and Nissan Leaf.
Basics of the water-cooled engine
Water-cooled engine has a coolant made of water in the water jacket around a cylinder and it circulates to prevent the engine from overheating.
A radiator is placed in the middle between the water pump outlet and inlet so that the performance of it is optimized. The whole route consists of radiator, radiator hose, water pump, thermostat and a cooling fan. A lot of narrow passages for a coolant flow through the main body of radiator called cores.
The purpose is to enhance cooling effect by increasing the area of water passing routes.
Let’s have a look at each components of radiator-related parts so that we can clearly understand each roles. The radiator itself merely doesn’t work. In combination with these parts, the purpose of radiator is fulfilled.
While running, the engine’s temperature is lowered with fresh air, but cooling only by air is insufficient for at the time of traffic jams during the time engine is still generating heat. Therefore necessity of a cooling fan arises. It increases quantity of air flow in front of the radiator and enhances cooling efficiency to the satisfactory level.
Water pump circulates coolant liquid in the water jackets around engines, radiator itself and its sub-tank so that the cooled coolant in the radiator runs back to the water jackets smoothly.
It plays a role to keep a fixed temperature of the coolant within a designated range. It stops the water flow to prevent a coolant from circulating in the radiator while engine stays cool enough under severe cold weather.
When an engine gets heat-up, water temperature accordingly increases, and it opens a water outlet fully when the temperature of coolant becomes approximately above 80 degrees Celsius and therefore coolant liquid start to circulate.
The temperature of the coolant sometimes rises to 120 degrees Celsius.
Then a pressure valve and a vacuum valve are located in the radiator cap respectively and when pressure goes up it due to the expansion of coolant liquid, a pressure valve opens and saves amount of coolant liquid flowing into the radiator and saves it in the reservation tank. When pressure falls down, a vacuum valve opens and returns a coolant liquid to the radiator. In addition, it suppresses the boiling of coolant liquid by keeping a constant pressure.
Maintenance of The Radiator
Check of the coolant
When the water level of the coolant decreases and gets dirty with rust and water scale, it mostly causes overheating of the engine. We recommend to change the coolant liquid every two years. When rust and water scale are in bad condition, let’s wash them out with a radiator cleaner.
Check of the fan belt
The tension of a fan belt which moves a cooling fan can be checked by hand. Please push the middle of fan belt with a thumb of your hand and if it is pushed down in between 13-20mm, it means that the tension of the belt is OK.
When it is damaged to the extent that the rubber part melts and slips, the turn cycle of the fan is jeopardized and it mostly causes the overheat.
Check of the radiator hose
A crack, slack and distortion of radiator hoses cause the water leak. Check regularly the conditions of radiator hose.
Have you ever suffered from overheating?
Please leave a car in the safe place and open the bonnet and wait till the water temperature falls. Never open the radiator cap because steam jets splash out when water temperature rises to an overheating level. When a coolant is short, let’s fill it to the designated level when the engine becomes cooler.
Damage of the water pump also becomes a cause of overheat because its role is to circulate coolant liquid as previously mentioned.