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Car Care Advice

9 Reasons Behind A Radiator Leak (+Solutions & How To Avoid)

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Your vehicle runs due to controlled miniature explosions in your engine cylinders. These miniature explosions give off a lot of heat — so regulating that heat is essential. 

The radiator is a significant element in your car’s cooling system that keeps the engine from overheating

Cool right? 

What won’t be cool is if you experience a radiator leak. 

In this article, we’ll discuss the top 9 causes of radiator leaks, how to identify a radiator leak, what to do about it, and how you can avoid radiator leaks. 

This Article Contains:

Let’s get started. 

Top 9 Causes Of Radiator Leaks

Dealing with a leaky radiator can be very vexing as a car radiator leak affects your vehicle’s operating temperature. If your engine doesn’t stay within operating parameters, it could cascade into even more problems down the road. So, be sure to watch your cars cooling system at all times. 

Here are 9 reasons why your radiator might be leaking:

1. There Is Corrosion In Your Radiator

Your radiator, just like any part of your engine, is susceptible to wear and tear. 

The constant pressure and heat handling can lead to rust, corrosion, and cracks. These cracks can develop into holes, and if the holes become large enough, your engine coolant can start seeping out. 

Losing engine coolant will lead to faulty temperature regulation. Faulty temperature regulation could spell disaster for your car. 

2. Wear In Your Radiator Gasket

Your radiator gasket sits between the coolant tank and the radiator and ensures that the coolant doesn’t leak. 

A worn-down gasket can cause coolant to start leaking, and the remaining coolant will then have to work overtime. 
(No one likes to work overtime, so don’t make your coolant do it.)

In this case, your mechanic can choose to either repair the gasket, if repair is possible, or they might replace it. 

3. Wear In Your Radiator Hoses

Your hoses can become weak and brittle as they carry the coolant throughout your engine. 

Your radiator hose connection points are most vulnerable to leaks. Your hose clamps experience a lot of pressure, and the pressure might cause them to come loose or even pop out entirely

A detached radiator hose will result in a large coolant leak that could wreak havoc on your engine temperature. Your mechanic might need to replace the entire hose and hose clamps or repair it, depending on the damage. 

4. Your Radiator Cap Is Leaking 

Your radiator cap is crucial as it keeps a lid on things. This component is also under constant pressure and a lot of heat. 

While a radiator cap leak is not likely to occur, it’s essential to have it checked to rule out the possibility. 

5. Your Water Pump Has Failed 

Your water pump is what pushes the coolant from your radiator to the engine. It also brings the coolant back to the radiator. 

Leakage from the bottom of the radiator often comes from your water pump, as this is where your water pump is. Corrosion or road debris can also damage your water pump. 

There are also hoses attached to your water pump; if a hose starts to loosen or detach completely, it’ll leak. 

6. Your Coolant Reservoir Tank Is Cracked

Your coolant reservoir stores the radiator fluid that your radiator needs to regulate your vehicle temperature.

All elements of your coolant tank (the plastic tank itself, the cap, and the hoses) are susceptible to damage. If any of these elements are damaged, this could be the start of your radiator fluid leakage problems.

7. Your Head Gasket Is Blown 

Your head gasket separates your engine block from the cylinder head. It ensures that the cylinders, your coolant, engine oil, and compression stay sealed. 

An issue with your head gasket could allow coolant to leak into your engine — causing the engine to overheat and eventually fail.

Replacing your cylinder head gasket is a costly repair. Thankfully, this is one of the least likely occurrences. 

8. Damage From Road Debris Or Impact

Your radiator is in front of your vehicle and susceptible to debris or collision damage. Some road debris can get through the grill of your car or even enter from underneath. If it hits your radiator or any part of your engine block, it might become a problem. 

Your mechanic will often suggest replacing the radiator if it has sustained any physical damage.

9. Cold Weather

Cold weather causes fluid to expand. If the coolant in your radiator expands, it can cause the coolant tank and hoses to crack or even burst.

Adding antifreeze to your coolant lowers the freezing temperature of the fluid. A lower freezing temperature means liquid expansion is less likely to occur. 

It’s essential to check your coolant level to avoid a build-up of problems that can come from a radiator leak. If the coolant and antifreeze run low, your mechanic will top them up. It’s best to get this done before winter to prevent issues when the temperature drops. 

Now that we know what might lead to a radiator repair job, let’s look at some ways you can spot a coolant leak. 

4 Ways To Identify A Radiator Leak

A leaking radiator can be highly problematic as it enables liquid or debris to enter the engine system and can lead to complete engine failure. 

Be on the lookout for these signs, as they could mean you have a leaky radiator.

1. Look For A Rise In Your Temperature Gauge

If your radiator is leaking, your vehicle’s coolant system is malfunctioning. A malfunction in your coolant system will cause the temperature gauge to indicate a rise in temperature and risk your vehicle overheating.

Overheating your vehicle can expose it to hazardous problems like your cylinder head cracking or engine exploding.

Scary right? 

The sooner you notice a coolant leak, the better. Early detection will allow you to prevent a pinhole leak or small leak from becoming a bigger problem. 

2. Take Note Of Any Puddles Under Your Vehicle

Coolant has a greenish hue and looks different from engine oil and water. Take a closer look at the puddles underneath your vehicle, if any: 

3. Check Your Coolant Reservoir Regularly

Your radiator is a closed system, so your coolant level should remain relatively constant. 

If you suspect a radiator leak, check your coolant reservoir. Mark the current level and continue driving your vehicle as per usual. Only recheck the coolant level once you’ve driven for a few hours. If the level of coolant has decreased, there is a definite leak. 

4. Visually Inspect Your Engine Bay

A small leak can cause coolant and water to get into places and rust the components. You can visually inspect your engine bay to see any rust build-up. The more compact the rust is, the bigger the leak. 

We’ve identified the signs to look out for that indicate a leaking radiator. 
Now let’s discuss what you can do about it.

What To Do About A Radiator Leak

The best solution is to contact your mechanic when you require a radiator repair. A professional dealing with the situation will ensure that repairs get done correctly. Professional help will save you money in the long run as they’ll prevent even a pinhole leak from happening again and your vehicle can continue functioning at its best. 

In case of emergencies, there are a few temporary solutions that can keep your vehicle running till you’ve contacted your mechanic. 

SAFETY FIRST: Always wear protective gear, like safety glasses and gloves, when working under your vehicle’s hood.  

Ensure your car has been cooled and is not running when you attempt these quick fixes: 

Now that you know what to do about a leak, let’s learn how to prevent a leaking radiator altogether.  

How To Avoid A Radiator Leak

Proper maintenance should ensure you’re not constantly running to stock up on radiator stop leak products or radiator sealant. It’s important for the hot water to stay where it is and to make sure your radiator valves are fully functional. 

To avoid a radiator leak: 

And if you’re in search of a professional, look no further than Repairsmith!
We will ensure everything is done to the highest standard, ensuring you avoid complete disaster.

RepairSmith’s team of qualified mechanics can perform repairs and maintenance to your vehicle right in your driveway. Our team is available 7 days a week, and you can book our services via the online booking system

Final Thoughts

We now know that the radiator is essential in keeping your vehicle running. Your vehicle needs to let off some steam to remain at operating temperature. Always have professionals like RepairSmith take a look if you have a car radiator leak. 

That said, your cooling system is not the only part of your vehicle you must constantly maintain — your engine, wheels, and brakes need to be looked after too.

Don’t have time to bring your car in for maintenance or repairs?
Book an appointment online, and RepairSmith’s mobile mechanics will complete your request in your driveway!