Hey, Why is My Car Leaking Coolant?

Hey, Why is My Car Leaking Coolant?
The cooling system in a vehicle is a closed system and should maintain the same level without fail. Sometimes conditions happen that will cause the coolant to overheat to the point of overexpansion, and it will cause a leak. Other times the coolant in the cooling system is neglected, and the coolant becomes caustic to its vessel and creates a leak. And still, just over time and age, components of the cooling system degrade, and a leak will start. If you add coolant, something is wrong, and if left unattended will turn catastrophic.

Is Your Car Leaking Coolant?

The coolant leak is commonly caused by a crack in the radiator, the heater core, or the coolant reservoir. The radiator commonly cracks if it’s old or if it hits an object. The leak can also be caused by a loose coolant hose, a faulty water pump, or even a blown head gasket.

Coolant is your vehicle's first protection against engine overheating; you're left vulnerable if it leaks. Checking your coolant levels regularly is a good practice since many leaks can strike unexpectedly. So, if you notice the levels dropping abnormally, something might be wrong.

Your cooling system requires routine maintenance. Coolant can turn acidic and eat away at gaskets and seals, causing dangerous leaks if neglected. In addition, factors such as temperature changes or simple wear can cause leaks.

While coolant does incredible things for your car, it is a toxic substance. It can poison animals and waterways if it leaks from a vehicle. In addition, because coolant gets hot when it's working, it can also scald someone standing near a leak.

Let's Get To The Bottom Of It!

  • Q: Do you have white smoke coming from the exhaust?

    You may also notice that the engine cranks long before starting. After the engine runs, you might see a small puddle of coolant under the car.

    Coolant passages between the head gaskets connect an engine's combustion chamber to the valve chamber. These passages dissipate heat from the engine block and the heads. Engine overheating or acidic coolant can damage the head gasket. When these gaskets are compromised, gasses from combustion get into the coolant passages, causing the coolant to become superheated. Superheated coolant leads to the engine overheating and further wear on the gaskets. Coolant leaks into the engine's combustion chamber when the gaskets are badly damaged, which you'll notice as white smoke in the exhaust. That's the coolant burning with the vehicle's fuel.

  • Q: Do you smell a sweet smell coming from the air vents?

    You may also notice that the windows stay fogged even when the defroster is on or that the carpet on the front passenger side floor is wet.

    Inside the air box in your vehicle's dash is the heater core. This circulates coolant so that your heater warms up the vehicle's interior. If the cooling system isn't maintained, the coolant turns acidic and can degrade the heater core. This can cause coolant to leak inside the vehicle. In addition, if coolant gets in the air box, it gets vaporized by air blowing over it and through your vents. You will notice this vaporized coolant as a sweet smell blowing through your heating and air conditioning vents.

  • Q: Does your coolant level keep getting low over time?

    You may also notice steam coming from under the hood or your engine is overheating.

    The coolant reservoir is the highest point of the cooling system and is filled with half air and half liquid coolant. When a leak in the reservoir occurs, the coolant won't be low in the tank until several heat and cool cycles force enough out. It is at this point that the low coolant is visible.

  • Q: Do you find a puddle of coolant under the vehicle after it has been parked overnight?

    You may also notice the "check engine" light is on or the "coolant temperature" gauge is running in the red.

    The coolant hoses attach the engine cooling system to the radiator. Since they are made of rubber, they will become brittle over time and can crack, causing a leak. Flex from worn motor mounts can stretch the hoses as well. A band clamp attaches the hoses to the radiator or engine block. Wear over time and from temperature changes causes leaks. These leaks are most common after the vehicle cools when various components contract due to the temperature change. When your car is parked, it's cooling, and you will see the leak as evidence of this wear.

All related issues checked?

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Hey, Why is My Car Leaking Coolant?

Vehicle Health Inspection Proof

Explore the following typical inspection results that show a potential cause for the symptom and select the one you believe is similar to your vehicle's issue.

Leaking radiator

The proof image shows the crusty buildup of coolant as proof that the radiator is leaking.

A customer dropped off their vehicle upon noticing some corrosion on the radiator. They thought the car's battery exploded, causing the problem.

The technician did not notice anything about the customer's concerns on the test drive.

During the vehicle health inspection, the mechanic noticed a lot of dried coolant on the upper tank of the radiator. The technician tested the battery and found nothing about the customer's concerns.

The technician used a cooling system pressure tester to pressurize the cooling system. They pumped up the pressure to the suggested rating on the radiator cap. Upon inspection, the technician found a small crack in the upper tank of the radiator that was causing it to leak coolant under pressure. The radiator requires replacement.

Does the issue look like this? if not accessible your shop will document it

Typical Fixes to Address the Cause(s)

The following chapters bases themselves on experiences from our auto repair shop; we'll describe related problems' causes and fixes.

"Radiator Replacement" fixes "Radiator Leak"

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Sometimes a problem is more challenging to describe than it initially looked like. If you are not sure your problem is described by this article, please find below similar vehicle symptoms, which might describe better the issue you are experiencing.

Other things your auto repair shop might talk about:

Engine oil. Coolant leak fix. Car's engine. Coolant tank. Hose connection.

Is Car Leaking Coolant
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