Radiator Stop Leak Review
83Radiator Stop Leak -- Does it Work?
I recently wrote a hub about engine oil stop leak and the benefits of it, and I wanted to follow up with a hub on radiator stop leak, because, even though they have similar titles, the two products are not the same at all. Stop leak varies greatly depending on what system you're using it for. Inside the engine, stop leak is designed to treat the rubber seals that keep oil from entering into the fuel mixture for combustion. Stop leak for engine oil is designed to soften and expand the rubber and keep the rubber seals fresh and working. Radiator stop leak is different. Radiator stop leak is designed to seal a leak that's happening somewhere in the cooling system, and if not used properly, side effects might ensue.
Radiator stop leak is a goopy substance that can cause quite a lot of trouble down the road if you're not careful. So before you go out and buy radiator stop leak, open up the hood of your car and see if you can't specifically locate where your leak is coming from. Many times, the leak will occur on a part of the cooling system that's easy to repair without the use of goopy additives like radiator stop leak. Below, I'll diagram what the cooling system looks like and how to try and diagnose where your leak is coming from.
When to Use Radiator Stop Leak
In the below section, we'll go through how to diagnose and find where your leak is. But sometimes, especially in certain older vehicles, there isn't just one leak. Sometimes the whole system needs to be treated. There are certain old Fords and other manufacturers that had numerous problems with the cooling system as a whole. In this scenario, radiator stop leak might be an excellent way to go, because it will treat the whole cooling system all at once. Just make sure you get the very best radiator stop leak out there. If you get a poor stop leak, it can clog up your pipes with goopy stop leak and cause unwanted pressure variances and larger problems. I've left you a link at the bottom to a product that has a lot of positive testimonials. Hopefully that will cut down on any side effects that sometimes pop up from poor quality radiator stop leak.
If however, your vehicle isn't an old beater and you think that your coolant leak might be fairly well localized to one spot, go through the next section and see if you can't identify the specific area where your radiator leak is. You don't want to neglect a cooling system leak. The first time I had one, the majority of my coolant disappeared in a day and I burned through a few quarts of oil because my engine got so hot. I had to replace not only my radiator but get an immediate oil change as well.
The Cooling System -- Finding your Leak
There are three main components to the cooling system of your car. The first is the radiator itself. This component is basically just a large aluminum heat sink, like the ones you might see on top of the processor inside your computer. The water flows from the hot engine through the radiator, with air rushing over the surface from the fan and from the outside air, getting cooled. Then the water flows back into the engine to reabsorb heat. The two tubes that carry the water back and forth from the engine are called the upper radiator hose and the lower radiator hose. Those are the second components of your cooling system.
The upper radiator hose carries the hot water from the engine into the top of the radiator to be filtered through the radiator and cooled. The processed water then flows through the lower radiator hose back into the engine to reabsorb heat. These two tubes, because they're made of rubber and undergo constant changes in heat, can wear out easily, or else become loose and begin to leak. The first thing you ought to check is whether or not your upper and lower radiator hoses are attached firmly and whether or not they're leaking. If you warm up your engine and open up the hood, leaving your car running, you should be able to tell whether the leak is coming from one of these two hoses, or whether it's coming from the radiator itself. If the leak is coming from one of the two hoses, you're in luck because they're pretty easy to change.
The third component of your cooling system is the coolant overflow tank. This is generally a clear plastic tank that's off to one side of the radiator. Most cars have two plastic tanks that each hold about a half a gallon of liquid. One is the coolant overflow tank and the other is the windshield wiper fluid tank. You'll have to identify which one is which. The windshield wiper fluid tank generally has the icon pictured to the right stamped somewhere on it or on the cap. If you really do have a leak in your coolant system, then odds are that your coolant overflow tank is completely empty. When the car is cold, the coolant overflow tank is at it's fullest. As you drive and more coolant is flowing through the system to keep the engine at a safe temperature, the coolant overflow tank adds more liquid to the cooling system. There's a chance that your leak is coming from the coolant overflow tank, but this is pretty rare. If the tank gets cracked and begins to leak, you'll be able to see droplets of coolant falling from it. If that's the case, then you're in luck again, because the coolant overflow tank is pretty easy to change out.
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Hi. We're Bar's Products, makers of Bar's Leaks and Rislone. Saw this discussion and wanted to throw our hat in the ring.
Though what you're saying in terms of negative effects this may be true for some products, it certainly is not for the majority of our stuff. In fact, we have items which actually *promote* heat transfer. This is beyond our Liquid Aluminum product which has the Xtreme Cool water-wetting agent; this is also true for our regular stop leak products.
Our stuff works in two ways to accomplish this.
There are millions of tiny particles in the regular Bar’s Leaks Radiator Stop Leak which increase the surface area and allow the cooling system to carry and disperse more heat. Second, we have our cleaning agent in our regular product which includes a host of ingredients specifically designed to keep the cooling system walls clean so they can efficiently transfer heat. Dirty walls don't work.
If you'll pardon a little tiny bit of advertorial, we think that if it could be explained exactly how a good radiator stop leak works and some real world “OEM” examples, that would dispel some of the myths about this category of chemical fixes. But the larger issue is there are, unfortunately, still a bunch of junk products in the marketplace (as you guys allude to), and that gives all good products in the market a bad name.
Thanks for reading.
BTW, if you have any comments/questions/concerns/good stories, please let us know. You can call us at 800-345-6572 x204. Ask for Fred.
Now if one of you guys will tell me how to repair a small crack in upper radiator tank on my 91 Camry i will be quite happy,i have heard they cant be repaired [PLASTIC]










BenjaminB 18 months ago
Benji from experience of having used this product from many different brand names many times I can attest that it only works on very minor leaks.
Because of this most products will say on the label that if it shows no improvement after a couple applications then you are going to need to get it checked out by a mechanic.
Over use of radiator stop leak can plug up your radiator fluid system through the engine,the water pump and thermostat and may cause damage to the engine as a result by not allowing it to cool properly.
There are many expensive products that if not applied properly can also set in your engine coolant channels very quickly upon the first application like a brick and then you will really be up the creek.So it's very important to follow the directions to a "T".
Depending on the type of radiator and where the leak is it may be repairable,but in most circumstances and with most radiators being plastic these days you are usually better off to replace it. If however it is a metal radiator and you can find the leak easily after removing the radiator then you can sometimes cram the hole full of something like JB Weld or a similar product and it will block off the leaking channel.
This is not recommended for a long term fix though as it does cut down the cooling ability of your system.