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What Is a Car Radiator?

car radiatorRegardless of outdoor temperatures, your engine is operating under very hot conditions. Keeping your engine cool enough to function properly yet hot enough to convert heat to energy can be a tricky operation. That’s where the radiator comes in, circulating coolant through the engine and back again.

The radiator is an essential component of the engine’s cooling system. This mechanism is designed to keep the engine temperature at an optimal level as set by the vehicle manufacturer. Made mostly of aluminum, radiators transfer heat from the hot coolant through tubes, then, as air blows across fins, it cools the fluid.

How the Radiator Works

The cooling system is a pressurized system comprised of several components working together to keep the engine cool. Coolant is used to cool the engine by circulating coolant through the radiator, engine, and the engine’s cylinder heads to absorb the heat. A thermostat placed between the engine and the radiator regulates the flow of coolant and maintains the engine’s temperature. If the coolant falls below the specified temperature, such as when the engine is cool, the thermostat restricts the flow of coolant. As the engine gets hotter, it opens incrementally as needed to allow fluid to flow through the radiator through the radiator hoses.

Radiator hoses are connected to both the radiator and the engine to direct the flow of coolant, so it can be cooled and then runs back to the engine to maintain the specified temperature, which helps to prevent overheating. To prevent the coolant from boiling, the system is designed to allow the boiling point to be raised considerably, similar to a pressure cooker. Unfortunately, too much pressure can damage hoses and other parts within the cooling system; at some point, the pressure must be relieved, which is the job of the radiator cap. The radiator cap is set to release pressure once it reaches the particular pressure that the system is designed to handle. The coolant returns to the radiator once cooled down.

Note: To avoid serious injury, NEVER touch the radiator cap or attempt to remove the cap on a vehicle that has been running. Wait until the vehicle has cooled completely. 

What Causes the Engine to Overheat

Most often vehicles will overheat in very hot weather, however, it can happen any time especially if the coolant level in the radiator is low or there’s a leak in the cooling system. Leaks can be particularly concerning as leaks in the radiator release coolant, leaving the radiator low which will most certainly cause overheating. If the radiator fails, the engine will overheat, causing serious damage, resulting in costly and extensive repairs. Other possible causes of overheating may relate to a malfunctioning thermostat, leaking hoses, or radiator cap. If the radiator cap is faulty, it is unable to hold pressure and allows coolant to overfill the overflow tank, which can cause the engine to overheat.

Preventative Maintenance Is Key

Though it’s virtually impossible to predict when a thermostat or radiator cap will fail, there are certain measures you can take to prevent the damaging effects of an overheating engine. Replacing your radiator hoses every 3 years or 36,000 miles not to exceed 50,000 miles is wise. Because the hoses are made up of rubber material, after time chemical reactions, dry air, and high temperatures cause them to break down. Coolant is the lifeblood of the radiator–be sure to check your coolant level often. A lower than normal level could indicate a leak within the system. A coolant flush every 30,000 miles helps to remove any contaminants that have built up in the system, and conditions and lubricates the system to help prevent rust and hard water deposits. Having a coolant flush performed on your vehicle helps keep your radiator working at its highest potential and preventing the inconvenience of an overheating engine.

Nothing is more frustrating or inconvenient than being on the side of the road with an overheating engine. Not only is it difficult for drivers, but repeatedly allowing the vehicle to overheat can have detrimental effects on the engine. Sun Devil Auto is the expert when it comes to all things automotive, especially preventative maintenance such as cooling flushes and hose replacements. Our ASE Certified Technicians can make sure you and your engine keep your cool any time of the year. Schedule an appointment at one of our many convenient locations for your next cooling system maintenance service.