Coolant leaks

How to Check for a Coolant Leak

Nidhi Nangia
By Nidhi Nangia. February 13, 2017
How to Check for a Coolant Leak

The cooling system of your car is crucial for the proper functioning of your overall engine, along with its performance and efficiency. The system circulates a mixture of water and coolant through your car’s engine and radiator under pressure, and its major function is to cool down the engine. The coolant’s temperature rises and it expands as the vehicle runs, and any excess may move into the reservoir tank thus causing a leakage. This oneHOWTO article is going to discuss about how to check for a coolant leak.

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Steps to follow:


Open the bonnet. If you suspect a coolant leak in your vehicle, the first thing you should do is to open your car’s bonnet and look into the engine’s interior. Most of the times, you will be able to detect a leakage with your naked eyes immediately. You will see big cracks probably on the pipes that lead to your car’s engine and the radiator. You will be able to see the main cooling hoses of the system, while the more intricate ones will be positioned beneath the vehicle. Sometimes, white smoke coming out from your car exhaust may also indicate a coolant leak.


With the car still on, listen to any humming sound that might be coming from the front part of your car. If your radiator system has a coolant leak, then you will be able to hear some sound coming from this part. The reason is the increasing pressure on your radiator causing vibrations in the area.


If you cannot detect any visible leak, then chances are that there is a minute crack in the operating system of the coolant. Set your air conditioning system to the lowest setting. If you feel hot air still pumping inside the vehicle, then chances are that your coolant system is about to fail. If there is an internal leak, then you will have to take your car to a repair service to get it examined and fixed.

How to Check for a Coolant Leak - Step 3

Step inside your car and turn the ignition on. Now open your bonnet and come out. Pour some water in the coolant container, and see if it drains quickly. If it does, then it is obviously leaking. You can see the water flowing out or squirting out of the auto part that needs replacement. You can repeat the process 2-3 times to ensure where the problem is coming from and where the leakage is.


Turn off the car’s engine and lift it into the air using a car jack. Now, you will be able to slide below the car and have a good look at its cooling system. You can refer to the car’s manual to get details about different components of its cooling system. Highlight the points using a torch so that each component will be visible clearly. If you are not able to identify any breaks, cracks or any damage, then your cooling system perhaps has an internal problem or leakage.

How to Check for a Coolant Leak - Step 5

If you have followed all these steps and you are still not able to identify the coolant leak, then it is advised to take your car to a professional garage. There, a fine liquid will be run through you car’s cooling system, which will seep out even through the smallest of cracks. This liquid has a strange color due to which it will become immediately visible. Once they spot the leakage, they will be able to handle it in a professional and expert manner.

If you want to read similar articles to How to Check for a Coolant Leak, we recommend you visit our Car Maintenance and Repair category.

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How to Check for a Coolant Leak