How Automotive Cooling Systems Work

An automotive cooling system serves three important functions.

  1. The cooling system removes the excess heat from the engine. 
  2. The cooling system maintains the engine operating temperature for optimum performance.
  3. The cooling system brings the engine up to the correct operating temperature as quickly as possible.

The cooling system has six main components—the engine, radiator, water pump, cooling fan, hoses, and the thermostat.

During the combustion process, depending on the engine and driving conditions, as much as 70% of the energy created is converted into heat.

cooling system graphic

The excess engine heat is transferred to the coolant being circulated through the engine by the water pump. Hoses carry the heated coolant to the radiator, where the cooling fan assists in transferring the heat to the air that is being blown through the radiator. The cooled fluid is then carried back to the water pump and recirculated throughout the engine.

A cold engine does not operate properly. To maximize efficiency, engines are designed to warm up quickly.

The thermostat assists with this process. A thermostat is a valve that opens and closes as a function of the temperature of the fluid flowing through it. It isolates the engine from the radiator until it has reached a minimum temperature.

Without a thermostat, the engine would lose heat to the radiator and take much longer to warm up. Once the engine has reached the desired operating temperature, the thermostat adjusts flow to the radiator to maintain a stable temperature.

At times, the coolant isn’t hot enough to open the thermostat all the way. When this happens, the engine is dependent on the radiator to keep the coolant temperature stable. As long as there is enough airflow through the radiator, the engine will not overheat. If for some reason the airflow rate is not adequate, the engine may overheat.

Other common causes of overheating are:

  • loss of coolant due to a leak in the system
  • a blockage in the hoses or passages in the radiator and/or engine
  • a malfunctioning water pump
  • a broken thermostat

Many of these problems result from a lack of preventive maintenance. Cooling systems are susceptible to corrosion, rust, and scaling. A BG Cooling System Service can prevent costly repairs resulting from cooling system problems or overheating.

Find a BG shop today and ask about the professional-strength BG Cooling System Service.

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