What Can Cause Car Engines to Overheat?

car check

Think of the engine as the heart of your car. It’s an intricate machine whose primary job is to pump air and fuel to get the car moving. Without it, there’s no way you’d get those wheels rolling.

That’s why the minute your engine temperature gauge spikes to “H,” find the nearest repair shop ASAP. Engine overheating is the ultimate car killer and should be taken seriously. That said, here are common reasons why your engine may overheat:

Faulty thermostat

The thermostat is responsible for maintaining engine temperatures at a sufficient level. It prohibits the coolant from gushing through the engine block until the engine has reached a safe operating temperature.

Initially staying closed, the thermostat will open at 95 to 110 degrees centigrade. Once it has done so, it signals a valve that allows the cooling system to function correctly. When a thermostat gets stuck and stays closed, the coolant is prevented from passing through the engine, resulting in overheating.

Leaks in the cooling system

Never underestimate leaks. They may look like minor issues but can easily turn into expensive repairs.

Watch out for small leaks in your radiator, hoses, water pump, heater core, freeze plugs, and thermostat housing. These can all cause major problems with the car’s cooling system.

Head gasket failure

The head gasket can be found between the cylinder head and the engine block. It’s responsible for keeping the oil and coolant apart as they travel from across chambers.

There are several reasons why your head gasket may fail. Most of the time, it occurs when people fail to warm up their engines sufficiently. When this happens, coolant can gradually drip into the oil system. That results in a sludge often called a ‘mayonnaise’ located on the oil cap’s lower side. Sludge consists of water and oil and may seem harmless at first glance. However, if left untreated, it could eventually result in overheating.

Some cars like Subaru use a single layer graphite head gasket. This type of gasket is designed to allow greater cylinder head warpage. However, it’s nearly impossible for the car to travel more than 120k miles without the oil dripping. While a Subaru head gasket fix may be a no-brainer, it’s a task that’s better left to trained mechanics. Head gaskets consist of intricate parts, and a single misstep can lead to bigger problems.

Defective radiator

overheating car

Radiators are heat exchangers whose primary job is to transfer heat out of the coolant into the air outside. That cools down the fluid and the engine. In a malfunctioning radiator, the coolant liquid will stay warm, which means hot fluids will pass through the engine and cause overheating.

Radiator malfunction is commonly caused by severe physical damage. In some cases, it can take the form of a broken fan, which could block hot air from exiting. Other times, leaks and clogs can damage the radiator and result in an overheated engine. Radiators can also be weakened by insufficient coolant levels, which can easily be solved using a coolant flush.

As with other things in life, prevention is better than cure. The best way to take care of your engine is to have regular radiator checkups and coolant flushes. Routine inspections can detect minor issues before they become bigger and costlier problems.

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