Why is my car overheating? Here they are the causes...

Engine overheating can be a nightmare for every car user. Some cases could damage the entire engine and make a lot of costs to repair and fix the damages, and some others can be safe with only a few fixing.

Most modern cars use liquid (coolant or antifreeze) to maintain the heat generated from the engine at a constant level. It is used many components and is gathered as a system called the engine cooling system.

Failure of engine cooling system will cause engine overheat, and the engine overheat can be known in several signs, such as:

• From the temperature gauge, when the pointer pointing at the HOT position
• Overheat warning lamp is turned on
• Steam from the engine hood
• If the car air conditioner system is blowing warmer air, even set the AC switch in ON position.
• etc

So, why is my car overheating? In this article, we will give you information about several car overheating causes. Here are six common car overheating causes.

1. The engine coolant is empty

The most common car overheating causes is because the engine coolant is empty. Engine coolant is the most important thing because it functions as a heat carrier, from the engine to the radiator.

When the engine coolant is empty, there is no carrier to remove the heat from the engine. As a result, your engine was unable to cool down and get overheating.

There are so many causes for an empty engine coolant. Most of because there were failures on engine cooling system components and made the engine coolant leak. Here are some examples that make the coolant leak:

• Bursts and collapse radiator hose
• Cylinder gasket blown
• Corroded plug block or cylinder head block
• Broken radiator
• Broken water pump
• etc

2. Radiator cap failure

Radiator cap failure is the next car overheating causes. The radiator cap is used to maintain the pressure to remain the same at a constant level. When it gets failure, the pressure inside the cooling system is unable to maintain and triggers the engine to overheat.

For more detail about radiator cap failure, you can read the post I have written before on 5 Symptoms of a bad radiator cap. And also, see the post about how to test a radiator cap if you want to inspect the radiator cap.

3. Radiator blocked

Another car overheating causes is a blocked radiator. A blocked radiator means that your radiator has blocked the way of engine coolant for circulating the entire cooling system channels.

In most cases, the engine coolant can only circulate inside the engine (mostly in the water jacket through the bypass hose). The coolant can not reach the radiator because it is blocked by mud or from corrosion debris. When the radiator blocked, the engine coolant could not cool down its temperature and made the engine overheat.

A blocked radiator can happen because the coolant replacement was too long and too late or using groundwater as an engine coolant.

Read also:

• Components of car engine cooling system
• How a radiator works?

4. Stuck thermostat

A thermostat is an important component of the engine cooling system. The thermostat controls the coolant circulation by opening or closing its valve were exposed by the heat. A stuck thermostat also is car overheating causes.

If the coolant temperatures exceed the thermostat temperature, then the valve is open and vice versa. In several conditions, the thermostat valve can be stuck by debris or mud or even break by itself because it is worn out.

The stuck thermostat mostly has the valve open. The open valve can not hold the flowing coolant, so the coolant will constantly flow, and there is no time to absorb the heat from the engine.

In the opposite places (in the radiator), the coolant temperature will never cool down. It's because it is always run to the engine before it's get cooled. It is why a stuck thermostat can make the engine overheat.

5. Radiator fan failure

Radiator fan failure is another common car overheating causes. A radiator fan is used to suck the air from the front of the radiator to flow through the radiator core pipes and fins. When the fresh air flows through the radiator core pipes and fins, the heat from the coolant is released.

Since the radiator fan has different models and types, the radiator fan failures are also different. For example, the radiator fan with viscous coupling will fail from the weak of the viscous coupling and the drive belt. In contrast, the radiator fan with an electric motor will fail from the electric components such as motor fan, fuse, socket, etc.

If the radiator fan gets failure, the radiator fan can not optimally cool down the coolant temperature. It is why the engine gets overheating, mainly if you drive in a traffic jam.

6. Waterpump failure

The last common car overheating causes is water pump failure. Waterpump is used to pump the coolant to circulate the coolant from the engine to the radiator. With this circulation, the coolant can cool down its temperature inside the radiator. The engine can use the cooler coolant from the radiator to absorb the heat that happens in the engine.

There are two common failures for the water pump. The first is leaking coolant from a gasket or corroded body, and the second is from a rusty pump blade.

Leaking coolant from the gasket makes the coolant drain out. The corroded pump blade will make the coolant not circulate to the entire cooling system. It is why water pump failures can trigger the engine to overheat.