What Happens When a Radiator Hose Blows?

Anyone who knows anything about cars understands the importance of a radiator. A radiator is an integral component of a car’s cooling system.

It is responsible for maintaining the temperature of the car and preventing the engine from overheating.

A blown radiator hose can cause a plethora of issues in your car starting from an overheated engine to leaking coolant, a faulty gasket, and much more.

Read on to learn more about it.  

What You Need to Know About Radiator Hoses

A radiator hose acts as a bridge between the radiator and the engine itself.  

The upper hose carries the hot coolant from the engine to the radiator while the lower hose is responsible for taking the cooled coolant back into the engine. 

It is the primary component through which the coolant circulates back and forth from the engine and the radiator which builds up your car’s cooling system.

A radiator hose is relatively inexpensive and you can find a replacement relatively quick. Try to immediately fix the issue because if you neglect the problem, it can cause severe issues with your car. 

You’ll notice signs like a coolant leak and an overheating car engine

If you don’t identify and fix the problem soon, you can end up damaging your car and putting a dent in your wallet trying to fix it.

Checking The Radiator Hoses

If you’re often facing issues with the car’s temperature or if you noticed leaking coolant, it might be time to check whether your radiator hose has busted or not. 

You can easily do that by popping up the hood on our car and physically inspecting the radiator hose.

Remember to perform this check after making sure that the car has had enough time to cool down. Leaking coolant can be incredibly hot and there’s a huge possibility that you can get hurt if you approach this carelessly.

If you hear a crunching sound as you move a radiator hose around, there’s a high chance that the hose has been damaged and needs to be replaced. 

Focus on the curved areas because there’s a higher probability of a burst occurring in that area. Mostly, any blown hose can easily be identified and is as obvious to see as a flat tire.

What Makes a Radiator Hose Burst?

The radiator hose is typically designed to last for a long time. Most manufacturers recommend changing a radiator hose after 5 years. 

But many factors can accelerate decay and cut off the hose’s lifespan, causing it to burst. We’ve listed down some of the major culprits.

1) Faulty Cap

A faulty cap stands as a major reason why a radiator hose can collapse. It can happen either due to age or by contamination from using cheap coolant. 

A faulty radiator cap leads to a vacuum issue and pressure built up which can cause the radiator hose to collapse or burst.

2) Blocked Tank Hose

A blocked tank hose can stop air from following into the expansion tank. Similar to the problems created by a faulty cap, the blocked hose creates a vacuum and leads to hose collapse. 

You can check a blocked hose by uninstalling it. After that, insert a plastic straw and blow through it to see if it has any kind of blockage or built-up stuck in-between.

3) Built-Up In the Radiator

Since the radiator hose is so interconnected with the radiator itself, any issue or blockage in the latter will translate immediately to the hose. 

A clogged radiator can cause a radiator hose collapse, specifically the lower hose itself. You may notice prior signs before the collapse occurs such as rising temperatures.

4) Age

Everything you drive your car; the radiator hose must move extremely hot coolant to and from the engine at very high pressure. Over time, the hose will naturally start to decay from the heat and pressure, causing it to be more vulnerable to bursts and collapse.

How Do You Know That You Have a Bad Radiator Hose?

If you’re driving around with a faulty radiator hose, you’ll get warning signs of something being wrong. The following are some of the things you need to look out for.

Leaking Coolant

The first indication of a faulty or collapsed radiator hose is coolant leaks. You might notice a bright color liquid fluid under your car. 

While a coolant leak can happen due to many reasons – even something as small as a loose radiator cap – a blown hose can be the cause of leakage.

Low Levels of Coolant

Related to the previous point, if you find yourself constantly refilling coolant in your car, there’s a high possibility that it could be coming from a faulty radiator hose.

The leak might not be noticeable or too small, but you should always check your car’s coolant level before taking it on a drive.

Overheating Engine

A radiator is responsible for maintaining our car’s temperature. any problem with the radiator or hose will be indicated through a rising operational temperature of your car. 

If you notice your car overheating even on a relatively cool day, then there might be a problem with your car’s cooling system. if so, one of the reasons could be a blown radiator hose.

Can You Drive with A Blown Radiator Hose?

You definitely shouldn’t. As mentioned before, the radiator is the primary component of your car’s cooling system. if you drive a car while there’s a coolant leak due to a blown radiator hose, you’ll be able to get around driving for only a little while.

Once the coolant has been drained entirely, the water pump will start to suck air. This will rapidly overheat your engine and can lead to extensive damage to the car’s internal functions.

Replacing A Radiator Hose

Replacing a radiator hose isn’t difficult at all especially if you know your way around the internal components of your car. Simply pick out a replacement at your local auto repair shop. 

Do remember to get a radiator hose which is designed for your car. Also, try to replace the radiator clamp while you’re installing the new hose.

You should also remember to put a mall pan underneath your car while you work otherwise, it could get very messy very quickly.

Quick Fixes You Can Do

You might be one of those people who aren’t comfortable with repairing their car or you might be looking for some quick fixes that you can do before replacing the hose. Try using insulating tape instead for a temporary fix.

You can get the insulating tape from any local auto repair shop or gas station. Wrap the tape tightly around the leak and you’ll be good to go. 

You can also try using duct tape if that’s what you have at hand. 

It won’t work for that long and you’ll have to visit your mechanic or replace the hose in either case as soon as possible.


A blown radiator hose can cause a lot of problems. This includes leaking coolant and an overheating engine. 

While you can try to temporary fix the problem using insulating tape, you should get the damaged hose replaced immediately as it can lead to severe problems with your car’s engine.


Dean Alvarez, TireForge Head Author

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