3 Common Causes of Coolant Leaks

The cooling system works by circulating a coolant and water mixture under pressure through pipes to your engine and radiator, thus cooling the engine. While you are driving, the coolant temperature rises, and the coolant expands, so any excess refrigerant in the system moves into a reservoir tank by way of rubber hoses. And if this process is not working correctly, you might have a big problem with the repair. So try to fix it as soon as possible to avoid expensive maintenance.

Identifying the Coolant Leak

There are three most common cases of a coolant leak, and they all vary. Sometimes the coolant can be collected on the ground under your car or your reservoir tank is not as high as it should be. This can lead to a slow leak in the system. Another cause of a coolant leak can be an overheated engine. Sometimes you can smell it if there is any leak. To determine the type a leak can be easy, but sometimes it can take a lot of your time to locate it. That’s why it is always recommended to check the level of the coolant reservoir tank with every few gas fill-ups. Let’s look at the most common cases of coolant leaks:

1. Leaky Radiator Cap

The coolant leak can happen because of a leaky or a weak radiator cap because it can overflow whenever the coolant heats up. The radiator is a pressurized system so if there is a loss of pressure from the cap not fitting correctly or if the cap is the incorrect cap for the radiator, the pressure will be lost and a leak could occur. Use a pressure test of the radiator cap to diagnose it. Check your vehicle’s manual for more information.

2. Internal Leak

If there is an internal leak, the coolant level will be always down, so you will notice it if you are always low on coolant. The reason for an internal leak can be a leak in the head or block or a leaky head gasket which lets the coolant escape its system.

3. External Leak

An external leak is very easy to determine. If there is an external leak, you can notice a spot where the leak is coming from, for example, a split or broken hose or a hole in the radiator. Another reason for a coolant leak can be caused by a leak in the water pump , or a heater core, and engine freeze plugs can also allow coolant to escape.You can also have a coolant leak if you have a cracked reservoir . The coolant keeps the engine from the overheating, that’s why if you have noticed a coolant loss, try to immediately determine what is the cause and fix it on time.


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