The Important Job Of Your Radiator Cap

When it comes to vehicles, most people know that they need to change their oil and pay attention to any check engine lights that come on. However, did you know that you also need to pay attention to the caps that are under your hood? Your radiator cap is more than just a simple lid, it plays an important part in your vehicle's cooling system. 

Where To Find The Radiator Cap

Your radiator cap is located under the hood of your car. If you're not sure where the radiator cap is, you can check out your vehicle's owner manual to discover its exact location under the hood of your specific vehicle. The cap is generally made of metal and has a warning on the top to never open when hot. 

What Makes Your Radiator Cap Special

Unlike all the other caps under your hood, the radiator is more than just a cap. It is actually a spring loaded plunger that performs two different jobs in order to help keep your radiator and engine cool.

Job #1: Diverts Coolant

The spring loaded plunger that is attached to the radiator cap is capable of measuring pressure. If the pressure inside of your cooling system surpasses the pressure capacity of the spring loaded plunger, the plunger diverts the extra coolant and the extra pressure into an overflow area. 

Job #2: Maintains Pressure

The second job of the cap and spring loaded plunger is to maintain the correct pressure inside of the cooling system. Your vehicle's cooling system needs to stay at a specific pressure rating. If the pressure gets too high, the coolant will start to boil, which will create excess heat and prevent your radiator from doing its job; cooling down the place. The radiator caps helps ensure that the pressure at the right levels.

Your radiator cap helps keep the pressure stable inside of your radiator, which allows the coolant to stay cool, flow effectively, and keep your vehicle running smoothly.

What Happens When Your Radiator Cap Doesn't Work

When your radiator cap doesn't work, your coolant system does not work effectively either. When the correct pressure levels are not maintained, the coolant in your radiator starts to boil. This prevents your radiator from being able to cool off your engine. 

Outward Signs Something Is Wrong With Your Radiator Cap

If your radiator cap is not working, your vehicle will give you a few signs that something is up. 

You should check under your hood every few months.  Fluid leaking from around your radiator cap is a sure sign that it needs to be replaced. If you have been driving your vehicle and immediately open the hood, you may be able to hear the radiator fluid boiling if your cap is bad.

Another way to detect that something is wrong with your radiator cap is by paying attention to the temperature gauge on your dashboard. If the needle on the temperature gauge goes past the middle line, your vehicle is running a little too hot. 

If your vehicle gets too hot, it may even overheat. You'll know your vehicle is overheating when the temperature gauge goes completely into the red. A warning light on your vehicle could come on. Your vehicle may also start releasing steam from under the hood. If this happens, you should pull over, let your engine cool off, add some coolant, and purchase a new cap for your radiator as soon as possible. 

Replacing Your Radiator Cap

Replacing your radiator cap may be one of the easiest repair jobs you ever do. All you have to do is purchase a new radiator cap that has the same pressure ratings as your current cap. The pressure ratings should be written on top of your radiator cap. If you can't find the ratings on the top of the cap, you should also be able to find that information inside of your owner's manual. 

In order to replace the cap, you need to let your engine cool down completely before you remove the cap. If you try to remove the radiator cap when your engine is still hot, you could release hot coolant and you could burn yourself.  Once your engine has cooled off, you can unscrew the old radiator cap. Place it to the side and screw the new cap into place. 

Although your radiator cap is not that intricate, it plays an important role in keeping your engine cool and your vehicle on the road. If you ever notice your vehicle is running too hot, check and see if the radiator cap needs replace. You can easily do this repair job on your own, but if you have any questions, be sure to consult with your mechanic.  

To learn more, contact a company like Action Muffler Radiator & Brakes for auto repair

About Me

Keeping Your Car Pristine

A little fender-bender might not seem like that big of a deal, but frame damage can go a long way. When I got into a little accident last summer, I wrote it off and figured that it wasn't a big deal. Unfortunately, I waited until I had already burned through a few sets of tires to have my car looked at by a professional. The goal of my blog is to help other car owners understand the importance of having their car repaired right away, instead of procrastinating. You never know what kind of underlying damage your car has, but a professional can spot damage and repair it correctly.


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