Car Radiator Leak

There are a lot of important aspects of your car that you might not know about besides the parts that you can see and the engine under the hood, many people aren’t familiar with the different parts of their car. All of the parts of the car come together and help make sure that the car runs smoothly. Because of that, it’s important to know how the different parts of your car works so that you understand what’s happening when you start having parts of your car wear out. Here’s more information about the radiator and what to do if you have a leak.

What Does Your Radiator Do

Your radiator is responsible for regulating the heat in your car. Your engine creates a lot of heat as it operates, and to prevent your engine from overheating, your car will pump coolant throughout your engine. The fluid receives heat and carries it away from the engine block. The coolant takes the heat generated by the engine and takes it to your radiator. This blows air across the liquid to cool it down and exchange heat with the air outside of your car.

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Essentially the radiator functions by bypassing coolant through a thin metal fin which allows the heat to flow to the air outside of your car. Sometimes there’s a fan that blows air across the radiator to carry the hot air out of your car. Radiators come in many different shapes and designs, but their primary function is the same no matter what shape or design. Essentially your radiator cools the coolant which cools your engine.

There are many parts of a radiator. The first part is the core, which is the largest part of the radiator and it provides the radiators primary function. It has a large metal block with a small metal fan that allows a coolant to vent to the air surrounding the radiator.

Then, there’s the pressure cap which is your car’s pressure system. The coolant system is continuously under pressure and this is because it allows a coolant to become much hotter without boiling it. The pressure cap creates pressure by using a spring.

Also, there’s the outlet and Inlet take which helps the radiator move coolant from the hot parts of your engine to the radiator.

Lastly there’s the transmission fluid. The transmission coolant is there because your car uses the same coolant fluid your engine uses to pull the transmission. The transmission fluid is removed through your engine in steel pipes, which are surrounded by coolant that conducts heat away from them. This coolant is also cooled within the radiator.

You now know all the parts of the radiator and their function. Because of all the fluid dealt with, you can probably see how a leak can occur. Here are the causes of a leak and what can be damaged if left untreated.

Causes of Radiator Leaks

There are not many things that can cause a radiator leak which makes it easy to figure out what the issue is. The leading and most common cause of radiator leaks is corrosion in the radiator.

Radiators, hoses, and hose connections collect sediment and rust, and overtime debris can put holes in the radiator. In some instances, weak coolant can also cause overheating. Poor service practices can also hurt the radiator, but if the radiator has been serviced by a professional, then this won’t be the cause. Also, overfilling the radiator can cause leaks from increased water pressure. A bad thermostat or heating core can create excessive heat and place pressure on the radiator.

You should always check the level of your radiator and strength of your coolant at the service station. Make sure to check the radiator when the engine is cold so that you don’t get very when it’s hot. Ask your car mechanic when you are at the garage to test the fluid. Mechanics can routinely check for a radiator leak and then change the oil or do other maintenance related work. You should see on the invoice all of the check marks in your mechanic will routinely check for in your car. If you have questions, you can talk to the mechanic and ask about your radiator.

You also want to make sure that when you buy coolant, you don’t buy cheap stuff. You also want to make sure that when you get your radiator fluid replaced, you always have the system flashed. Rust and sediment can collect in the passageways and hoses, which can build up and cause a plug. This could cause leaks in the future and make the engine overheat. Rust eats holes in the radiator so you definitely want to make sure that you’re getting your system flushed.

No Maintenance – if you fail to maintain your vehicle, you’re going to experience a lot of problems such as a leaking radiator. Maintenance involves checking parts of your vehicle and making sure their operating smoothly. If you check and maintain your vehicle often enough, then you’re going to prevent a lot of issues that could go wrong in your car and save you money from fixing it at the dealership.

If you want to avoid radiator problems or other issues and save $100s of dollars that you’ll spend at the auto repair shop, you’ll need to service your vehicle often – you can use our mechanic-rated Auto Maintenance and Repair Manual to do this. It’s basically what mechanics use to go through your vehicle to check if there are any problems that need fixing. As soon as they notice the most minor problem, they’ll ask you to fork out some money even though it’s a problem you can fix yourself in minutes – the manual will teach you how to maintain your vehicle every few thousand miles and it’ll teach you how to fix minor problems that mechanics will ask you to pay for; saving you money in the long run.

A lot of our readers have the Auto Maintenance and Repair Manual printed on their garage wall and 92% of them haven’t visited the auto repair shop in the last year because they know what to do to avoid problems. All it takes is giving your vehicle a little attention every few thousand miles and you’ll never spend money at the workshop again.

Signs of a Radiator Leak

There are a few signs that you should be on the lookout for if you suspect that you have a radiator leak. One of the signs is that the coolant is leaking. Coolant is something you can easily check in the see-through overflow tank. Look at the levels and see if it’s empty or low. Then check the coolant level in the radiator, but this should be done only when the engine is cool. If you have too little coolant in the car’s cooling system, the engine can overheat and make your heater blow cold air. If you know that you’re losing coolant after looking at these parts, then this could be a sign of a radiator leak.

Some radiator leaks are easy to spot because there’s a puddle underneath the radiator but others aren’t as easy. Check the radiator from every angle and pay attention to the seams at the bottom of it. Rust inside the radiator and holes from debris can also cause coolant leak so you want to look for these things to. Also your vehicle might have an aluminum radiator that won’t rust, but aluminum can corrode and have pinhole leaks, so look for signs of that.

If you believe that you have a leak, but you can’t find it, you want to get it checked by a mechanic. Coolant has a way of escaping only when under pressure and the car is running, so you definitely want to get an expert opinion.

Leaks can also occur in the radiator core. Most cores have long tubes welded into a header, and there are tanks at either end and fans between the tubes for air cooling. Modern radiator cores are usually made from aluminum and older vehicles may have copper. With thermal expansion, vibrations, and impact, your radiator can end up degraded and with leaks.

Also, radiator tanks are another source of coolant leaks. Depending on how your radiator is constructed, your tank can be directly welded to the core or be crimped plastic tanks that use a rubber gasket. Tanks can allow coolant to escape in either of these cases. It can be hard to inspect your tanks since radiators are difficult to access under the hood of your vehicle. In this case, a mechanic might be the best option because they will be able to move your radiator safely.

Your radiator hoses, tubes and filler neck can leak also. Rubber radiator hoses are known for getting dry and cracked, especially on older cars. Clamps and clips can wear out and they might have a weak hose attached to the radiator. Your radiator cap should also be inspected from time to time so that you can know if the spring is weakening and allowing coolant to leak

These are all places where a car radiator can begin leaking. It can be beneficial to inspect all these places yourself, but going to a mechanic might be the option that is easiest.

Fixing a Radiator Leak

There are a few things you should keep in mind about radiator leaks. Depending on the reason for the radiator leak, you could be looking at a full replacement. If the leak is small, you could be looking at something you can fix with a commercial product. Keep in mind that no coolant leak will stay small for long because they will expand. With all of the pressures and temperatures going on in your coolant circuit a weak ;eak will become bigger and bigger inevitably.

One of the ways to address a radiator leak is to pour a bottle of liquid sealant product (View on Amazon) into the radiator. These consumer products can address a radiator leak because it will circulate and plug any leaks. This is a convenient and safe way to fix radiator leak. All you have to do is wait until the engine is cold and follow the directions on the product container. All of the products are different and have different directions, but otherwise for the most part they are the same.

Most of the time all you have to do is shake the bottle, put the radiator stop leak in the coolant reservoir or radiator, and run the engine up to operating temperature. This formula will make its way around the engine and radiator and it will fix any pinhole leaks, holes or cracks in your radiator. Many of them say that they are a permanent fix, but realistically you should still visit your mechanic if you notice recurring leaks.

Sometimes you have no choice but to go to a mechanic. Coolant can escape when only under pressure when the car is running and it might possibly escape in the form of steam. This means that you are likely not going to be able to find where the leak is located. If this continues to evade your detection, you might consider using a radiator stop leak additive as mentioned above, but it’s always better to repair the issue. This is why going to a mechanic might be the best choice. Even though the sealant is a quick and easy fix, the mechanic is definitely something that will help you long term. All in all, the mechanic is a lot less expensive than replacing your car.

Car radiators are an important part of having a working vehicle. Because of that, leaks need to be seriously handled. You want to definitely consider getting to know your car radiator and getting used to inspecting it for leaks. If you do suspect that there is a leak because you’re noticing symptoms of a car radiator leak, then the first thing you can do is make an appointment with your local mechanic.