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Everything You Wanted To Know About Car Radiator Steam But Were Afraid To Ask!

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Life is filled with little disasters guaranteed to raise anxiety levels in a person. As a first-time car owner, it is common to panic when you see steam coming from your bonnet because your car radiator is overheating. However, does an overheated radiator mean that your car is doomed? It's time to increase your knowledge about what radiator steam means so you can keep the anxiety levels at bay when it happens to you.

Why is the Radiator Steaming?

The first thing you need to understand is why the radiator is steaming in the first place. The good news is it's not because the radiator is on fire! The steam is simply an indicator that the engine has overheated. This has caused the liquid within the radiator to boil, and the steam is the result. There are multiple reasons why the radiator overheats, and these include:

A leak in the radiator which is allowing water to escape. Some leaks let you know of their presence when you see the water pooling under the car, but some leaks are internal ones, so there is no obvious sign until you see the radiator steam. Leaks can either come from the radiator or its hoses.

Radiator fan failure often makes itself known if your car only overheats while idling. The fan pulls the cool air through the radiator while you are sitting stationary. So if your car is fine out on the motorway, but gets hot while sitting at lights, your radiator fan could be to blame.

Trapped air in the radiator can cause problems too. This is because the coolant cannot move through the radiator as it is meant to. The coolant is in the radiator to keep the temperature cooler, so inefficient coolant means a hot radiator.

Now that you know why your radiator is overheating, you need to know what to do when it happens to you.

Dealing With an Overheating Car Radiator

The first thing to remember when you see radiator steam is that it is a dramatic symptom of a problem, but you're not in immediate danger. As soon as you can, pull your car off to the side of the road. Continuing to drive with an overheated engine can lead to engine damage such as a cracked engine block.

You will need to add some water to your radiator, but you cannot do this until your engine has cooled a little. Removing the radiator cap at the top of the radiator while the engine is still hot can cause hot liquid to explode. Turn the car off and let it cool down for 30 minutes. Then, release the radiator cap one-quarter turn at a time. Each time you turn the radiator cap, stop and allow the built up pressure to release before you make the next turn. Once you have fully undone the radiator cap, top up the radiator with room temperature water. Never use cold water in an overheated radiator because the sudden temperature change causes the metal to quickly constrict and crack.

Once the water has been refilled, drive your car to your local radiator shop so they can diagnose why the radiator is overheating. It is not an issue you can ignore by just adding water each time it overheats. The more the engine overheats, the more likely you risk incurring permanent engine damage. The radiator shop will check for leaks, test your thermostat, and bleed excess air out of the system if it is found. Radiator repairs often take no more than a couple of days, depending on how busy the shop is. Now you know why a radiator steams, you can quell the panic if it happens to you.