The Anatomy of Healthy Cars: A Service and Repair Blog

Possible Causes Of Your Car Overheating

by Brittany Marshall

The combustion engine in cars generates a lot of heat. The cooling system is designed to keep your car cool and running at optimum temperature.

The water pump pushes coolant from the radiator throughout the engine and transmission systems and back to the radiator. The hot coolant is cooled while travelling through the radiator, before being rerouted back through the engine. So the heat created by the engine is dissipated via the radiator.

If your cooling system has a problem, it can lead to overheating and major mechanical problems. Following are five possible causes of overheating.

Low Levels Of Coolant

The first thing to check if your car is overheating is the coolant level in the radiator. Never open a radiator cap when the engine is hot as you could get burned; wait for the engine to cool first. The coolant level can also be checked via the reservoir.

Dirty Coolant

If the coolant is dirty or rusty, this means that the radiator needs to be flushed out and the coolant replaced. This will not only lower the engine running temperature, but it will remove any debris that could damage the cooling system.

Check your owner's manual or with your mechanic for the recommended frequency of how often your radiator should be flushed out and also for the recommended type of coolant.

Worn Out Hoses And Leaking Radiator Cap

If the hoses are brittle and cracked, spongy or bulging around the clamps, they need replacing. Damaged hoses can provide an exit for leaking coolant. If coolant is being lost through the overflow pipe, this can indicate a leaky radiator cap.

Damaged Fan Belt Or Water Pump

The fan belt drives the water pump and alternator. The water pump moves the coolant throughout the system. If the fan belt is frayed or cracked, or if it squeals or squeaks when driving, it is probably slipping and needs to be replaced.

A malfunctioning water pump itself is another possible cause of overheating.

Inaccurate Thermostat

Car engines are designed to run at their optimum when they are 'warmed up'. The thermostat works to prevent the coolant moving throughout the system until the engine is warm and at optimum temperature.

Sometimes the thermostat can become damaged and get stuck in the open or closed position. If it is stuck in the open position, the engine takes a long time to warm up, as the coolant is not being held back until the engine is warm (as it should be).

Alternatively, if the thermostat is stuck in the closed position, this will prevent the coolant from circulating, and in a relatively short time, the car will overheat.

Radiators and cooling systems are necessary to keep car engines running at optimum temperatures. It is wise to have regular check-ups to prevent problems developing down the track. Preventative checks of the coolant level, the hoses and the radiator cap are a good start. Your local radiator shop should be able to assist with any radiator repairs and with more extensive checks.

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