Top 5 Bad Radiator Symptoms (Replacement Cost)

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The radiator is an important part of a car’s coolant system; it helps to keep the engine cool, and running at operational temperature. If the radiator is bad, other components that make up the cooling system would be affected, and in turn, the engine would be badly affected too. But what are the various bad radiator symptoms you should know?

In most cases, a bad radiator can cause engine overheating, stalling, rough idling, and coolant leaks. These are practically the major signs that depict a bad radiator, or even a bad radiator cap. Notwithstanding, there are other uncommon signs such as check engine light illumination.

This article explains the major symptoms of a bad radiator. When you start noticing any of these symptoms, it is advisable that you act immediately to fix whatever is causing the problem before it skyrockets.

What Does the Radiator Do?

The radiator is a component in every car’s cooling system, which houses coolant liquid, and prevents air from getting into the cooling system – and the engine, subsequently.

Although radiators are used in a wide range of applications, in automobiles, their major function is to remove and eliminate heat from the engine in a bid to keep the engine cool.

Automobile radiators work with a thermostat valve/sensor. The sensor detects excess heat inside the engine and opens up so that hot steams can escape, while coolant and water are then sent into the engine from the radiator to keep everything cool.

With the explanation above, a bad radiator would result in an overheated engine, which put every component in the engine bay at great risk of failure. In worst scenarios, overheating can wreck the engine totally.

See Also: Symptoms of Bad Radiator Cap

What Are Bad Radiator Symptoms?

1. Engine Overheating

As already hinted in the introduction, engine overheating is one of the commonest signs of a bad radiator.

Here’s how it occurs; when the engine heats up and the thermostat opens to allow coolant from the radiator to get into the engine; because the radiator is bad (damaged), it may not send coolant into the engine; thus, increasing the heat level inside the engine, which would inevitably lead to overheating.

When you notice that the thermostat indicator is always in the red zone, and your engine overheats often, that’s a clear sign that something is wrong with your car’s cooling system – and you may guess, it could be the radiator.

2. Coolant Leaks From The Engine Bay

Another sign that your car’s radiator is faulty is when you see coolant leaking out from the engine bay. This usually occurs if the radiator cap is loose, broken, cracked, or the radiator itself has a crack on the body.

So, if you can see coolant leak out from under the engine bay, have the radiator inspected for possible damages.

3. Damaged Radiator Fins

When the radiator is bad, you’d notice that the fins are scattered – not properly arranged. The damaged fins could get clogged, which would block air passage – causing the radiator not to carry out its functions effectively.

Damage to the fins can also occur during installation; maybe you replaced the old radiator, if the mechanic doesn’t install the new one correctly, or manhandles the radiator during installation, it can lead to damage to the fins.

4. Low Coolant, Always

There’s a particular level the coolant liquid should not exceed, and there’s also a level it shouldn’t go below.

If you notice that the coolant level of your car is always below the indicated marking on the reservoir tank, then you need to check the radiator for leaks, and the reservoir tank too.

5. Passenger Heater Not Working

A bad radiator can cause the heater in the passenger area to stop working. The heat produced by the heater is actually heat from the engine. When the hot coolant passes through the heater core, a fan then blows the heat into the cabin/passenger area of the car.

So, a bad radiator can affect this process, which means the heater would seem not to work. As the driver you may not notice this issue; it is the other passenger in the car that’d notice it and draw your attention.

Can You Repair a Bad Radiator?

Yes, you can repair a bad radiator; however, if the damage is pretty too much, it is best to replace the radiator with a new one. Radiator repairs are advisable when the damage is minor leaks; you can even use stop leak products.

If the damage is a deep, long crack/broken part, then you really should get a new one – trying to repair such faults may lead to costlier damages in the future. Well, getting a brand new radiator is pretty expensive, which is why a lot of people opt-in for repairs instead of replacement.

Bad Radiator Repairing/Replacement Cost

It’s way cheaper to repair a bad radiator than to get a new one. If you opt-in for stop leaks products, they are sold for less than $10 in many stores, and if you’re going to have a mechanic do it, then you should expect to pay around $50 – $150 depending on the level of the leak(s).

On the contrary, getting a new radiator costs from $680, up to $1,500 or even higher depending on the type of radiator your car uses. Of course, radiators are built differently with unique features for some specific models – all of these are what could increase the cost of replacement.

What More?

So, what are bad radiator symptoms? The commonest symptom is overheating. However, asides from overheating, a bad radiator can make coolant leak out, and this would cause the coolant level to always go below the indicated level.

Rarely would a bad radiator trigger the check engine light; but, if the radiator has been damaged for a long time, then it’s possible that the situation has affected another component, which then triggers the check engine light.

Caution! When you discover that your car’s radiator is bad, do not attempt to touch the radiator immediately after stopping the car. Allow the engine to get cooled naturally before touching the radiator, else, you may get severely burned on your palms.

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