Why a Coolant Leak Is A Serious Problem You Can't Ignore

A car relies on several different fluids, and all of them could potentially leak from their reservoirs. While some fluid leaks are generally harmless, others could be catastrophic. An example of that would be a coolant leak that happens from the bottom of the vehicle.

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You must never ignore a coolant leak from the bottom of your car. Firstly, antifreeze in that coolant is flammable, and a spark could quickly start a car fire. Besides that, the engine can overheat, and that could cause the car to shut off or the head gasket to blow. In winter, a coolant leak will leave the engine unprotected, and it could freeze from the inside.

This guide will teach you more about your car’s relationship with its coolant. Then, you’ll discover the problems resulting from a coolant leak underneath the vehicle.

Why Is A Coolant Leak A Serious Problem?

Here are the 5 reasons why leaking coolant from underneath your car is such a serious problem:

1. Antifreeze Is Flammable

Antifreeze consists of ethylene glycol or propylene glycol, among many other ingredients.

As the name suggests, antifreeze is designed to stop the engine from freezing in extremely cold climates. However, it also works on the other end of the temperature spectrum to prevent the engine from overheating.

Despite how people use the terms ‘antifreeze’ and ‘coolant’ interchangeably, they’re actually two separate things. Antifreeze on its own isn’t coolant until it gets mixed with water, typically at a 50:50 ratio.

Whether you call it coolant or antifreeze, it’s a crucial substance to help the engine function despite extreme temperatures.

The problem:

The first reason a coolant leak is a serious problem you must never ignore is that it is flammable. That’s largely thanks to the chemicals in antifreeze that serve an important purpose but can also ignite into flames given the right circumstances.

In other words, the coolant dripping underneath your car can burn and set your vehicle alight. The danger becomes even greater if so much has leaked that a puddle forms underneath your vehicle or if it flows down your driveway.

Read: What Happens If The Car Engine Coolant Is Low?

2. Engine Will Overheat When Driven

Combustion engine vehicles run incredibly hot, which should be no surprise. After all, an engine generates power by continuously igniting an air/fuel mixture in its chambers to turn a crankshaft.

Those continuous explosions generate so much heat that an engine can overheat within minutes. Thankfully, those engines have cooling systems circulating coolant to manage the temperature and prevent that from happening.

Read: The Fastest Way To Cool Down An Overheated Car Engine

The problem:

The second reason a coolant leak is so severe is that it will lead to engine overheating, without a doubt. That’s because the leak gradually empties the coolant reservoir, leaving the engine with nothing to prevent it from reaching dangerously high temperatures.

Worse yet, the leak happens out of your regular line of sight, directly underneath the vehicle. As a result, there’s a strong likelihood you’ll get in your car and start the engine without realizing the leak at all.

Within minutes, your engine could be overheating and steam coming out from under the hood.

3. Car Could Shut Off Immediately

Late-model vehicles these days are more computerized than ever before. They come equipped with countless sensors throughout the car, ensuring everything functions correctly.

Those sensors collect data and feed it to the onboard computer, optimizing the car’s functions to keep you and your passengers safe on the road.

One such function also lets the computer know if or when the cooling system fails, and the engine is overheating. Those sensors monitor things like coolant levels and engine temperatures and supply that data to the computer, which then reacts according to its design.

The problem:

In the previous section, you read that a coolant leak from the bottom of your car can cause the engine to overheat. Some cars are equipped to quickly sense that problem as it happens and warn you about it with indicators on the instrument panel.

Some cars are designed to shut off completely when coolant levels drop and overheating occurs. That is a protective measure to ensure the engine doesn’t damage itself at dangerously high temperatures.

Unfortunately, the car might shut off with little or no warning. That could happen while you’re still driving on a busy road, causing you to suddenly lose power in your car and leave you stranded.

4. Head Gasket Could Blow

The head gasket is a critical part of your engine that seals the combustion chambers. Doing so ensures that each chamber maintains the necessary pressure to ignite air and fuel and generate the power your car needs to move.

Besides that, the seal formed by the head gasket also prevents coolant and engine oil from leaking to wherever they don’t belong, either in the engine or throughout the engine bay.

The problem:

At this point, this guide has established that a coolant leak will cause the engine to overheat. Aside from a possible shutdown of the entire vehicle, overheating also causes the head gasket to fail completely or ‘blow’.

That will cause a chain reaction leading to several major problems like the following:

Compression loss: A blown head gasket means the combustion chambers can’t maintain the necessary pressure to generate power. As a result, the engine has to work extra hard to produce an output, driving its temperatures even higher and making the overheating condition much worse.
Oil and coolant leakage: A blown head gasket means the engine loses its seal. Oil and coolant will leak out around the engine. Remember: coolant is flammable, and the conditions under the hood will likely cause a fire within moments.

5. Engine Will Freeze In Winter

As mentioned earlier, antifreeze doesn’t just prevent a car’s engine from overheating. On top of that, it also ensures that your engine doesn’t freeze and turn into one giant block of ice during the winter.

Related: Why Your Car Won’t Heat Up

Due to that, you’ll be able to start your car and run its engine without a problem despite the low temperatures outside.

The problem:

You must never ignore a coolant leak because it leaves your engine vulnerable to the effects of extremely cold temperatures. Naturally, this is only a concern for you if you live in a cold climate or if the leak happens during the winter.

Your engine always has moisture inside of it. That’s because fluids like engine oil and coolant have water in them.

Without your antifreeze leaking out from underneath your car and its reservoir drained, you’ll have none left to stop your engine’s insides from freezing.

Bottom line: you’ll be unable to start your car’s engine and get to wherever you need to be, all because your engine has frozen from the inside.

Final Thoughts

Overall, the list above clearly shows you why you must never ignore a coolant leak coming from the bottom of your car. Whether it’s a tiny leak consisting of a slow drip or a huge puddle has formed underneath, you must fix the root cause.

After that, you can refill the reservoir with sufficient coolant to keep your car functioning correctly. Do it quickly and you won’t have to worry about your car overheating or your engine freezing in the winter.