Radiator Stop Leak Concentrate (1196)

Radiator Stop Leak Concentrate


  37 Reviews

Stops and seals antifreeze/coolant leaks. Bar’s Leaks Radiator Stop Leak Concentrate is specially designed to stop minor to moderate cooling system leaks and drips caused by normal cooling system wear and age. It works with ALL types and colors of antifreeze coolant and/or water. Which is one of our commitments to customers: no matter what product you choose, our radiator stop leak or something else entirely, you can also count on effectiveness and ease-of-use.


NOTE: Cooling systems that are dirty or partially clogged should be flushed before usage.

Shake well. Pour Stop Leak into a cool radiator. If direct access to radiator is not available, install in overflow / reservoir tank. One bottle treats 4 gallons. Use 1/2 bottle for four cylinder engines. Fill radiator and overflow tank to proper level and reinstall cap. Drive/idle engine for 15 to 30 minutes. If leak continues, a second application may be required, or mechanical attention is needed. After successful installation, Leave Bar’s Leaks in the cooling system for continued protection.

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At Bar’s Leaks, each of our products is easy to use. There’s no special automotive expertise required. If you can pop the hood on your car, you can use our radiator sealant and other products. Each of our solutions is affordable, costing just a fraction of what you’ll spend working with a mechanic. And each of our products comes with the promise of effectiveness.

Our radiator stop leak concentrate is one of many chemical repair solutions available at Bar’s Leaks. This product is specially designed to stop minor cooling system leaks and drips caused by normal cooling system wear and age. It works with ALL types and colors of antifreeze coolant and/or water.

All you have to do is watch Bobby and Caitlin in our how-to videos and follow our easy installation process. These videos are created to make a simple-to-use product even simpler to understand and apply to your vehicle.


At Bar’s Leaks, our chemical solutions go beyond just radiator leak sealant. We also offer chemical repair solutions for problems related to cooling systems, head gaskets, engine oil, power steering, transmissions and more. As with our radiator sealer, there’s no special automotive expertise required. Each product is affordable and effective, and each works quickly — especially when compared to the cost of visiting a mechanic.

You’ll no doubt find other radiator leak sealant products, but not all of these products work as advertised. In fact, many can actually make your situation worse. At Bar’s Leaks, each of our products is the result of careful research and testing by our top-flight chemical engineers. These professionals are always improving our current products in pursuit of perfection, and they’re also constantly developing new products in response to auto manufacturer innovations and new technologies.

Made in the U.S.A., just an hour outside of Detroit, each Bar’s Leaks product is heir to a legacy nearly 70 years old. We’ve been serving everyday drivers for decades, offering special solutions that are far more convenient and far more affordable than seeking professional help at the repair shop. When you need a radiator leak sealant you can trust, choose Bar’s Leaks.

Get your radiator sealer today.

Customer Reviews

  37 Reviews
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 37 reviews
 by Privaterace
This stuff is miracle

I’m currently stuck in a lemon lease due to desperate needs. I think that my 2008 Hyundai Sonata radiator has been leaking for a long time, and I didn’t notice until it became worse. I followed the directions. It took almost 2 days to fully seal but it definitely worked.

 by Norton S.
Very happy with results

I used concentrated radiator stop leak part #1196 and it worked as described, very happy with the results.

 by Norton S.
Worked great, 5 stars

I used Bar’s Leaks Radiator Stop Leak Concentrate (1196) for a small leak in my radiator and it worked great. I would give it 5 stars.

 by Bob L.
Solved the leaks

I’ve used both the radiator stop leak as well as the head gasket sealant and was completely satisfied with both products as they solved the leaks and made my ride enjoyable again. 

Car - Audi A6

 by Nick S.
Amazing product

Product: Radiator Stop Leak Concentrate Sealer 

Soon after I bought my used 2005 Ford Mustang, a puddle of antifreeze coolant always appeared under the car every morning.  Upon inspection, I noticed that coolant was leaking on the short side of the radiator.  I tried all kinds of sealers from auto stores.  None worked.  During my weekly trip to the supermarket, I bought Bar's Leaks Radiator Stop Leak Concentrate Sealer. After two doses, the leaks were sealed!  It lasted about a year before another dose was needed.  It's been months since I've seen a leak.  Thankfully!  Amazing product!  I even bought an emergency bottle.

 by Eddie P.
Nothing but 5 stars

Hi my name is Eddie, I used the stop leak for radiators on my mom's 2005 Acura MDX years back and it held great for 3 years until she traded it in. Probably still going strong, people say it clogs stuff and everything, but they are stupid because if that was the case, we would have had plenty of issues with the cooling system as it was in it for 3 years. I will use it for any other issues like that my family has even though I hope I don’t have to LOL. Nothing but 5 stars for this product.

 by Donnel S.
Never lets me down for cooling system leaks

I call it magic mechanic in a can. I’m 78 years old and I can’t remember the first time I tried Bar's Leaks to stop an annoying radiator weep. The results made me a believer for not only emergency situations but for maintenance. I like and tinker with old British iron, specifically Jag, Triumph and MG. All these makes are long-established leakers. I always had a sticker proclaiming Bars Leak on my entire past race, solo, and rally cars. Bar’s Leaks is a great product line that has never let me down.

 by Mark S.
Always does the job

I've used the Maximum Strength Radiator Stop Leak (1196). For as long as I can remember and it has never failed to stop whatever leaks I had.

 by Mercutio
Best brand out there

I used Bar's Leaks Radiator Stop Leak (part 1196). It just works!

 by Rolf D.
Did its job

The Bar's Leaks product I’ve used in the past was the Radiator Stop Leak, and it worked fine back then. Over time, the radiator ended up going because the tanks started to leak and corrode, so I had to purchase a new one by then. But for the leaks before that, Bar's Leaks worked great.

Glad we could help, Rolf! Thanks for choosing Bar's Leaks.

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