Hey, Why Is My Radiator Leaking?

Hey, Why Is My Radiator Leaking?
The radiator is a component of the engine's cooling system. It is located in the front of the vehicle and uses airflow across the radiator core to transfer the heat developed during engine combustion to the outside air. The system is under pressure to allow the system to operate at higher temperatures to help with complete combustion and minimize vehicle emissions.

Have You Noticed a Leak In Your Vehicle's Radiator?

A radiator leak is commonly caused by a loose/broken radiator cap, damage in the radiator hose, internal chemical electrolysis, or a crack in the tank due to impact or wear. Also, note that a coolant reservoir leak can be commonly mistaken for a radiator leak.

This can result in overheating, engine damage, and unreliable performance. So, it's crucial not to overlook the bad signs and take prompt action. For example, if you notice coolant puddles or a decrease in your vehicle's coolant level, it indicates a leaky radiator. Ignoring these warnings can lead to costly repairs and inconvenience down the road.

Remember, promptly addressing radiator leaks is an investment in your vehicle's longevity and peace of mind.

Let's Get To The Bottom Of It!

  • Q: Do you see a red, yellow, or green crust around the radiator hose ends?

    The radiator hoses are like flexible tubes made of rubber. They connect to the radiator and the engine block through firm hose adapters. They carry the coolant from the engine to the radiator and back again. Over time, the rubber hoses can become stiff and fragile because they're made of rubber. Additionally, when the coolant becomes acidic, it gradually weakens the hoses from the inside. If you notice a coolant leak, it may be because the hoses start leaking at the connections between the fittings and the hose itself. You might see a dried, crusty material of a specific color, meaning that the coolant has been leaking.

  • Q: Is the engine oil texture resembling a milkshake?

    The head gasket is like a seal that connects the engine's head to its block. Its main job is to keep the coolant passages separate from the oil passages and the combustion chamber. However, the coolant can become acidic if the engine gets too hot or the cooling system wears out. This acidity and electrolysis can damage the head gasket and create leaks. As a result, the coolant can enter the cylinder and pass through the piston rings, eventually ending up in the crankcase where the engine oil is stored; this results in a mix of coolant and oil. When this happens, the engine oil looks milky, resembling a dark milkshake.

  • Q: Are there pinhole leaks in the radiator?

    The coolant must have a certain alkalinity level to stay healthy. However, as time goes by and the coolant gets used, it becomes more acidic. This acidity allows the coolant to conduct electricity. This creates a process called electrolysis, which can damage plastic and aluminum parts in the engine. As a result, these components start to wear out, and small holes, called pinhole leaks, can form.

  • Q: Do you notice coolant puddles under your vehicle?

    The radiator comprises two tanks on each end of the core. Its purpose is to allow coolant to flow from one tank through the core, into the other tank, and back to the engine. The radiator's core is typically made of aluminum or copper, while the tanks are made of plastic. A rubber seal between the core and the tanks is in place to keep them connected. However, as time passes and the radiator is used, this seal can become weak and brittle, eventually cracking. When this happens, it can lead to a leak underneath the vehicle.

All related issues checked?

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Hey, Why Is My Radiator Leaking?

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 coolant reservoir

The proof image shows the coolant reservoir leaking at the seam, which explains the low coolant level. Therefore, the coolant reservoir must be replaced with a new one to fix the issue.

When the customer brought in their vehicle, they were concerned about the low coolant light popping on the dashboard every morning. The light would turn off after driving for a while, but now it's consistent. The customer also mentioned they hadn't noticed any coolant puddle on the ground.

During a test drive, the technician confirmed that the low coolant light was on. As part of a vehicle health inspection, the technician discovered that the coolant level was low, and there was evidence of coolant underneath the coolant reservoir.

To further investigate, the technician used a coolant pressure system tester. After filling the coolant correctly, they pressurized the system to 12 psi. Unfortunately, the coolant reservoir was leaking at the seams during this test. This leakage was the cause of the low coolant level, and the reservoir will need to be replaced.

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.

"Coolant Reservoir Replacement" fixes "Leaking coolant reservoir"

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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:

Coolant leaking. Internal combustion engine. Losing coolant.

Is Radiator Leaking
Your Issue?