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Common Problems With the Radiator in Your Car Truck or SUV

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Created on: 2020-10-17

In this video, Len discusses the most common problems that will eventually happen to any radiator, so that you can know what to look out for

Okay, friends. In this video we're gonna talk about common radiator issues. We're not necessarily gonna talk about overheat conditions, but issues that you might find with your radiator. One of the first common things that you might happen to notice if you have a radiator leak is your engine's temperature starts rising up. Maybe you're driving in your vehicle and you're looking at the gauges and you see that gauge just start going up, up, and up. The reason for that is because the radiator serves a very important job in your vehicle, and that's job is to support and cool the engine's cooling system and even sometimes the transmission's cooling system. Now, as your engine's running, it's gonna have a whole bunch of tiny explosions inside of those combustion chambers. That's due to the mix of the air, the fuel, and, of course, the spark igniting it. This, of course, is gonna create a lot of high temperatures inside of your vehicle's engine. Each cylinder, of course, is gonna make its own heat. So if you have a four-cylinder or an eight-cylinder, you have to kind of imagine what type of heat's gonna be there. If you have an eight-cylinder, there's gonna be a lot more of those explosions, a lot more heat, so you're gonna need a lot more cooling in your system.

Now, something to think about is that the normal operating temperature on most vehicles is gonna be between 195 and 220 degrees Fahrenheit. With that said, if your temperature is going above that 220 degrees Fahrenheit and it's not able to cool down the engine the way that it should, you're gonna find that you have an overheat condition. Now, the radiator has a very important job. Like I said, not only is it gonna be cooling that engine, but in a lot of cases, if you have an automatic transmission, it's also gonna be cooling the transmission.

With that said, for some reason, they put the radiator right out in front of the vehicle. The reason for that is because air needs to be able to flow through it unrestricted. They did put it behind a nice pretty grill so it looks more aerodynamic and nice overall. Now, unfortunately, being in front of the vehicle, it's gonna be exposed to all of the elements and, of course, any debris that might be inside the road that you're driving on. And, of course, the air has to be able to flow freely and unobstructedly through those cooling fins. If there's something blocking them, you're gonna have an issue.

Now, the cooling fins love their job. And in all honesty, they're really good at it as long as they're kept clean and free of debris. Being in front of the vehicle, the radiator's exposed to a lot of external forces, such as nature or debris from the driving atmosphere you're driving on, maybe such as that dirt road that you love to drive down, or even a piece of rubbish that maybe flew up from the road that didn't make it to the rubbish trash can there. Okay. So maybe you're wondering what else could possibly go wrong with these cooling fins. Well, they're made out of very thin aluminum. With that said, aluminum is a very soft metal. If you were to look right down at the radiator right here, what you might happen to notice is that they're pinned over or pinned over. If you happen to see this, obviously that's gonna cause airflow restriction that's supposed to be getting forced through the radiator and be able to cool the coolant that's flowing through. Of course, your engine needs all the help it can to be able to cool down, especially if you have a bigger motor such as maybe a V8 or even a V10 or something like that. And, of course, something else that you might happen to see would be your cooling fins are actually falling apart or even your radiator starting to separate. There really isn't too much that I need to tell you about that because I'm sure you can imagine what would be happening.

Okay. So that's pretty much all I've got on cooling fins, but there is more to your radiator that you need to pay attention to. You're also gonna have plastic tanks. On some vehicles, they might be located on the top and the bottom. Other vehicles, you might happen to notice they're from side to side. These plastic tanks are gonna be filled with coolant so there needs to be a seal in between the area where connects onto your aluminum part of your radiator. If you haven't been keeping up with your maintenance or cleaning of your fins of your radiator, you could find that you have an overheating condition. In which case, as the coolant overheats, it's gonna expand and, of course, there's gonna be more pressure inside your cooling system. These tanks are made out of plastic generally. Plastic tends to crack, especially if it's under pressure, so you might happen to find that you have a crack in your actual tubing of your radiator. Another common place for your radiator to leak would be the seal that goes between the tank and the aluminum aspect of your radiator. A common reason why that might happen is, of course, well, seals break down over time.

Something that might help that break down a little quicker though, would be if you have a contaminant in the system. For instance, on this particular tank of a radiator, if you were to look on the inside, you can see the area where the transmission fluid is supposed to flow through to be able to cool down. If there was an issue with any of this and your transmission fluid made its way into the cooling system, of course, it's gonna be a contaminant and the transmission fluid is gonna break down that seal on you. Now, if you keep up on your cooling system maintenance such as maybe flushing the system or even taking a nice garden hose and spraying out inside of those fins, it's gonna help make sure that your radiator lasts for a very long time. It's easy and it's the least thing you can do for your cooling system.

So let's go ahead and talk about some things you should think about if you're replacing your radiator. You never wanna open your cooling system when it's hot. So if you go over to that radiator cap and you happen to notice that it's very hot, you definitely don't wanna open it. The reason for that is because the contents inside your cooling system are gonna be hot as well. So if it's hot and it's under pressure, once you open that, where's this gonna go? Up like this. And you definitely don't wanna get burnt, you definitely don't wanna get sick from ingesting it, and you definitely don't wanna get blind from getting it in your eye. The second thing that I'm gonna talk about for this is, of course, you wanna flush your cooling system before you go ahead and exchange anything inside your cooling system such as your radiator, your thermostat, or even your water pump. The reason for that is because by flushing it, of course, you're gonna get out the old, possibly contaminated fluid, or at least the used fluid and you're gonna be able to replace it with brand new fluid, something that's a little bit better for the engine overall.

Another thing that flushing your system before you start doing the job will help you with is it'll let you know if you have an obstruction in some place. Maybe you have a blockage and maybe your heater core or something else, and this is gonna help let you know that ahead of time. Another reason why you might wanna flush it is due to the fact that if there is any contaminants in there, you wanna make sure they come out and you also wanna make sure you see what's coming out so that way there you know what's going on. When it comes time to filling your cooling system, it's super important to make sure that you use the manufacturer-specified coolant. Something else that you wanna pay attention to when you buy that coolant is if it says concentrate or 50-50 mix. If it says concentrate, what you need to make sure is you mix it half concentrate and half distilled water. If you mix that up a little bit and you put in too much water or even too much concentrate, you're gonna have an issue where you don't have a 50-50 mix and your freeze point might be off. So going with pre-diluted colon is the easiest way overall.

Something else that's pretty much a must when replacing your radiator would be replacing the radiator cap at the same time. The reason for that is because as you'll notice on the lower aspect of your radiator, you have a little spring, and that's the activator valve. Once there's a certain amount of pressure inside your cooling system, this is supposed to open up and it'll allow fluid to overflow into your overflow tank. If this is weak, you're not gonna be able to have enough pressure inside your cooling system and as soon as the coolant temperature starts to rise a little bit and it expands, this is just gonna kind of let it go and it's not gonna stay in the cooling system the way that it's supposed to. They're inexpensive and you have it off anyway.

Now, the next thing I wanna talk about is replacing the thermostat. It's not necessarily something that people generally do when they replace the radiator, but it is something that's a great idea to do when you're servicing your cooling system. Overall, they're not super hard to do and if you're replacing the radiator, you have to drain the cooling anyway. The thermostat serves a very important job. It needs to be able to keep your vehicle at optimal operating temperature. If for some reason it's weak and it opens up too easily, that's gonna make it so your vehicle will actually heat up much slower. So if you're in the wintertime and you need your vehicle to heat up, well, it's gonna take a little longer. On the other hand, if it's stuck in the closed position, it's gonna restrict the flow of your coolant going through your system and you're probably gonna notice you have an overheating condition.

Something else that I'm gonna mention real quick is, in my opinion, you should never use a radiator stop leak kit. The reason for that is because they usually come in little tabs and once those tabs dissolve inside your cooling system, they're gonna dissipate and all the little particles are gonna flow around through your cooling system. As this is going on, what's supposed to happen is those little particles are supposed to find any little hole where a coolant could be seeping or leaking out of and they're supposed to fill that hole. The problem is they don't kind of only go there. They don't know that that's their only job. What they tend to do is actually just sit wherever they want. With that said, you have a lot of stuff going on in your cooling system. You'd have that thermostat that I showed you, you have the radiator cap that I showed you. You also have a heater core that's located inside and behind your dash. The coolant needs to be able to flow through all these freely. If it has built up because a lot of this stuff just kind of floated around and accumulated at one spot, it could block up that thermostat, which would be an issue, it could block up that heater core, which, of course, would be a major issue, and, of course, it leads a lot of sludge inside your cooling system which is just gonna be a mess. The best thing, of course, would be to be able to find the leak and fix the leak ASAP. The last thing you wanna be doing is driving around with a leak where coolant's getting on the ground. In my opinion, the best thing to do would not be to use the stop leak, it would be, of course, find a leak, find the issue with the part, and, of course, replace it.

Lastly, if you have an issue with your radiator leaking coolant, it's not only gonna be a safety issue for you, but it's also an issue for the environment. Coolant's a chemical and it's poisonous to you or anything else that might happen to ingest it and you have to also think if it's super hot, it might vaporize and it might get into the air, which, of course, could lead to health issues. Maybe you're breathing it in or it gets into your eyes or face. Generally, if you smell a sweet smell towards the front of your vehicle, that means you have a leak in your cooling system. It could be vaporizing out of there. If that's the case, you need to have it fixed ASAP.

Okay, friends. Any time you're gonna be working on your cooling system, you always wanna make sure you have hand and eye protection. With that said, hopefully, you liked the video. If you did, smash on that Like button for me. It would mean the world. While you're at it, why you go ahead and subscribe and ring the bell, that way there you can be kept up with all of our latest content. Thanks.

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