Your cooling system is composed of several parts that work together to ensure nothing stays too hot for too long. Here’s a quick rundown.
Your car, truck or SUV’s cooling system is composed of the radiator, coolant, water pump, thermostat and hoses. A working cooling system has a water pump that pushes coolant, which is also known as antifreeze, from the radiator through hoses that run through the engine block and heads. The coolant begins as a room-temperature liquid and is heated as it flows through the hot engine. The hot coolant is pushed through thin tubes in the radiator and is cooled by the air buffeting the radiator from the grill at the front of the vehicle. Then the process repeats until you stop the car and turn off the engine.
The radiator has fans to maintain the air flow when your car is stopped or slowing down. The fans remain on when the air conditioner is running, but if the A/C is off, the fans only turn on when the thermometer sends them a signal to indicate they’re needed.
The thermostat is located between the engine and radiator to ensure the coolant remains within the acceptable temperature range. If the coolant is too cold, the thermostat blocks the flow and forces the coolant to return to the engine through a different tube. If the temperature is too high, the radiator cap will release pressure and any fluid loss is reserved in a tank to cool. After it cools down, the lost coolant is returned to the radiator supply.
Your car radiator is composed of a series of thin, flat tubes that transfer heat from your engine to the atmosphere. Coolant also travels through the radiator to be cooled and recirculated through the engine. The radiator has fans mounted to it on the side nearest the engine. These are the fans that turn on to cool the radiator when the vehicle is not in motion or if the radiator exceeds safe temperatures.
The water pump is mounted on the front of your vehicle’s engine and it’s responsible for pushing coolant throughout the engine. It is only active when the engine is running and its sole purpose is to create pressure to force coolant through the numerous hoses and pipes throughout the engine and radiator. Without the water pump, the coolant will not move and your engine will overheat.