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Bad Radiator Symptoms and Replacement Cost

A radiator is more important than people might think. It’s an essential part of the car and its cooling system.

A failing radiator can be quite dangerous. The risks range from an overheating engine to feeling like it’s the Sahara Desert inside your car. To prevent this from happening, you need to act fast.

To do that, you have to learn what the signs of a bad radiator are. In this article, we’ll help you do just that. We’ll discuss some of the most common signs as well as replacement cost.

Signs of a Failing Radiator

In order to understand the symptoms, first, we need to learn what a radiator actually does.

When the car’s engine is running, it can get very hot. The radiator is a part of the vehicle’s cooling system that prevents the engine from overheating. In the simplest terms, it works by fanning cold air and cycling water and coolant. It then pumps it back to the engine and repeats the process.

During this process, plenty of things can go wrong, and they can lead to a faulty radiator. Now, here are some of the most common signs of a bad radiator:

1. The Vehicle is Overheating

If you notice that it’s unusually hot in the vehicle, this may be because the engine is overheating. This means that the radiator has not done its job properly.

In this case, you should act quickly since the side-effects could be very dangerous. The insides of the car could melt together because of the heat, eventually leading to a complete breakdown.

Not only is it dangerous, but it can also be very expensive to fix. So to avoid spending a fortune on car repairs, we suggest you visit a mechanic right away.

2. The Coolant is Leaking on the Ground

Another symptom of a bad radiator is a noticeable leak. If there’s a puddle of syrupy-smelling green liquid under your car, you’re probably looking at a faulty radiator.

The leak can happen on almost every part of the radiator, so it’s not easy to detect. That’s why we suggest you let a professional handle it. However, no matter where the radiator is leaking, the best and the safest solution is to replace it completely.

3. The “Low Coolant” Light is On

In case you didn’t see the green puddles, another sign of a leaky radiator is the ‘low coolant’ light. It will go off if there’s not enough liquid coolant, go figure.

So if you refilled it not so long ago but the light is still flashing, there might be a hidden leak in the radiator. Make sure you don’t add any coolant at this point. Not only is it wasting the liquid, but it could also be even more damaging to the car.

Instead, take your vehicle to a mechanic, as they will know what to do.

4. There is “Goo” in the Radiator

This is one of the less noticeable symptoms, but it’s an important one. A faulty radiator can contaminate the typical green or yellow coolant and turn it into brown goo.

Because of its consistency, the goo can’t flow back to the engine, which is why it will stay and pile up in the radiator. Much like all the other symptoms, this one also has the potential to be dangerous.

If it’s not taken care of, it could damage the transmission or even the engine.

5. The Radiator Hose Has Collapsed

Sometimes, when the radiator breaks, its hose will break too because of all the heat. In that case, the radiator needs to be replaced, alongside the hose.

On the other hand, if the main problem is the hose itself, it’s not as big of a deal, and there’s no need to replace the entire radiator. Still, we advise you go to a mechanic to get an accurate diagnosis of the problem.

How Much Does a Radiator Repair Cost

One thing is certain — whatever the issue may be, it’s best to let a mechanic diagnose and fix the problem. But how much does this cost?

A simple leak or hose repair will set you back around $30 to $50. However, every other radiator issue is typically solved by replacing the radiator altogether.

An average full radiator replacement will cost around $500, but it depends on the model of the car. For newer models, the replacement can cost up to $1200.

Richard Reed
I've been a General Manager of a moving company and I've also been a Professional Mover for over 30 years. I've driven flat beds, reefers, dropdecks, moving vans, heavy machinery, etc. In my time as a Mover I've driven over 1,000,000 safe miles. My days of moving and driving truck are past me but The Vehicle Lab allows me to share the knowledge I've gained over the past 40 years.

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