Car engines generate power through high temperature and pressure gases, generating excess heat due to combustion and mechanical friction. Excess heat must be removed and maintained at operating temperature.
Cooling system parts
Parts involved in cooling the engine are :
1 Water pump
2 Radiator
3 Thermostat
4 Coolant temperature sensor (CTS)
5 Coolant ( Antifreeze+ water)
Water pump
Water pump is the heat of the cooling system which pumps the coolant it consists of an impeller a pulley flange and an O – ring the impeller is driven by the engine drive belt through a pulley
Radiator
The radiator is a heat exchanger used to transfer the excess heat developed by engine to the atmosphere the radiator having an inlet port outlet port ,a drain plug and a radiator pressure cap the radiator pressure cap plays a vital role in the cooling system
Thermostat
The thermostat is a valve which regulates the flow of a coolant and helps to maintain the proper operating temperature for the engine the thermostat consist of a frame, charge cylinder main valve ,main spring bypass valve and secondary spring
Coolant temperature sensor (CTS)
It is used to monitor the engine temperature the ECU will use this data to manage fuel injection and ignition time some engines have more than one coolant temperature sensor the data is also used to control the radiator fan and to update the temperature gauge on the driver console it consists of a sensing probe and an electrical connector most coolant temperature sensors are the negative temperature coefficient type which means the temp increases the resistance will decreases the CTS is a can be two pin type or a three pin type depending on the make of vehicles
Working
How these part working together ?
Pistons in the engine block function to prevent compression leaks and oil or coolant leaks. The head gasket provides sealing between the engine block and engine head, preventing leaks. The engine head has a safe passage through which coolant can flow without entering the cylinder or mixing with oil. The water pumps coolant throughout the system using a radial impeller, driven by the engine using a serpentine belt. The thermostat regulates the flow of coolant, covering it in coolant to sense temperature. When the engine is cold, the bypass valve stays open, allowing coolant to recirculate through the engine. As the coolant reaches a higher temperature, the bypass valve closes and the main valve opens, allowing cold coolant to flow to the engine side and hot coolant to the radiator.
How to maintains the pressure ?
The role of radiator pressure cap it consists of a spring loaded valve mechanism which will respond to higher pressure reaching a pressure about 15psi will push the pressure cap valve and the coolant flows the expansion tank until the pressure goes down to operation level and when systems cools down the vacuum inside the system sucks back the coolant from expansion tank in case if there is to much pressure build up in the system due to trapped air or other failures the coolant in the expansion tank will be pushed out through the overflow hose
Heater system
The car heater system is a part of the engine cooling system the heater system consists of the heater core ,inlet and outlet hose a heater control valve which is optional and cannot be found in all vehicles the heater core act as a radiator dissipating heat from the hot coolant to the vehicle interior using a blower
