Cooling System Repair (1150)

Cooling System Repair


  23 Reviews

Bar’s Leaks Cooling System Repair has twice the cooling system repair performance of other products by not only stopping cooling system leaks, but also adding future protection. It’s scientifically formulated to stop coolant leaks, thereby reducing antifreeze loss, while correcting other cooling system problems and helping to prevent costly repairs and breakdowns. In addition, Cooling System Repair contains Xtreme Cool™, which stops overheating and reduces water temperature.


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

Install only in a cold engine. Shake well. Pour entire contents of the dual-chamber bottle directly into the radiator. If direct access to radiator is not available, install in reservoir/overflow tank. Fill radiator overflow tank to proper level and reinstall cap. Drive/idle engine for 15 minutes. If leak continues, second application may be required or mechanical attention is needed. Leave Cooling System Repair in cooling system for continued protection. Depending on the cooling system problem, results will either be immediate or noticeable within two (2) days or 100 miles of driving.

Available at:

Napa Logo


We know it can be frustrating when you’re in a rush and notice a puddle of fluid under your car. We’ve been there. There’s no question that fixing coolant leaks and other car leaks can be incredibly frustrating and inconvenient for everyday drivers. Lucky for you, we have the perfect product to help you get back on the road and back to your life.

This formula’s performance is the result of decades of research and careful testing by our team of top-flight chemical engineers. At Bar’s Leaks, you’ll find products that are designed and manufactured to fit into the lifestyle and budget of everyday drivers just like you. There’s no shortage of coolant leak products on the market, but many of these products fail to get the job done, and others can make your cooling system problem even worse.

At Bar’s Leaks, you find only proven products that get the job done. There’s no special automotive expertise needed. In fact, if you know how to pop the hood of your car, you can use our antifreeze stop leak products.

Our product will help you quickly and safely get your car back on the road. It’s worked for hundreds of thousands of customers — it’s time to let it work for you.


Don’t break your budget paying for expensive leak issues related to cooling systems, head gaskets, engine oil, power steering or transmissions. Trust Bar’s Leaks for chemical repair solutions that alleviate these issues and more. We’re the best-known leak repair brand in the industry, because we have nearly 70 years of experience in delivering highly usable, effective, and affordable products to drivers. The moment when you notice a puddle underneath your vehicle no longer needs to be a moment of panic. With antifreeze stop leak and other products from Bar’s Leaks, you have fast and easy solutions that won’t strain your wallet.

Bar’s Leaks is also made in the U.S.A., just an hour outside of Detroit. To ensure that we’re always staying ahead of the latest automotive technology innovations, our team of chemical engineers is always developing new products that can repair leaks even in cars with modern technologies such as direct injection, turbocharging and other modern automotive systems. When you have a leak that desperately needs repair, trust the experts at Bar’s Leaks.

Get your cooling system repair solution today.

Customer Reviews

  23 Reviews
Submit your review

Create your own review

Average rating:  
 23 reviews
 by Mikhail A.
I must say I am thoroughly impressed

I recently used Bar's Leaks Cooling System Repair to fix a leak in my car's radiator, and I must say I am thoroughly impressed with the results.

Not only was the product easy to use - simply pour it into the radiator and let the car run for a bit - but it worked quickly to seal the leak and prevent any further issues.

I noticed a significant decrease in the temperature of my engine after using this product, which indicates that it is effectively repairing and improving the cooling system.

Overall, I highly recommend Bar's Leaks Cooling System Repair for anyone experiencing leaks in their car's cooling system. It is a reliable and affordable solution that will save you time and money in the long run.

Hey Mikhail, thanks for the detailed review!

 by Kerem D.
Worked in one use

I really like it, worked in one use. Highly recommend this item for small leaks.

Glad to hear it, Kerem!

 by Josh F.
I highly recommend this product

The Bar's Leaks High Mileage Cooling System Repair Additive is a great solution for older vehicles with high mileage. The 16.9 oz bottle is easy to use and can be added to the radiator with no need for special tools or equipment. After using this product, I have noticed a significant decrease in coolant leaks and my engine runs cooler, it's a great way to extend the life of your older car. Overall, I highly recommend this product to anyone who owns a high mileage vehicle and wants to prevent costly repairs.

 by Benny A.
What an amazing product

What an amazing product! We use these in busses and it stops all the heater core leaks and radiator leaks! There are about 4 heater cores on busses and I believe if all 4 were leaking they would all seal up! Thank you for an amazing product!

Thanks Benny! Glad to see we are helping you with your fleet maintenance!

 by Lori K.
I cannot thank you enough

Hello, first I have to say that you are life savers. Words cannot express how thankful I am to you for your product. I am Lori and have not a clue about cars. I have a 2014 Chevy Cruze, and every time I would drive it, I had to put water or antifreeze in it and the temp gauge was teetering the danger zone every minute. Had to constantly keep an eye on it, drive with heat on and window down.

I stopped at my mechanic's one day. I lifted the hood and he looked from about a foot away (because he was working on another car) and said "it is a cracked cylinder head". I was devastated, I cried for 2 days. I only have 4 payments left after 7 years and I am attached to my car. He said it is not worth fixing it. So, I have to make it last until it's paid off in Feb. Or pay someone to take all the parts off and part it out. Sickening.

Well, I Googled my problem and Bar's Leaks came up. I went to AutoZone to buy your product. The guy that worked there said if it was a cracked head, it would be smoking out the exhaust, a milky residue would be around the motor and or you would have only been able to drive it for 2 or 3 days. There isn't any smoke, no milky residue, and I have been driving it for 2 weeks. He thinks it is the water housing. So I bought the Cooling System Repair part number 1150.

It was so easy , just poured it into the coolant overflow and let it idle for 15 mins. WOW! It did not have to put in a drop of water after the 15 min idle, it was not ready to overheat. So happy. I have driven it twice since then and still have not needed and water .. and it is driving so much better. When stopped at a light I cannot even hear it running, just like it was when it was new. Simply amazing! I tell everyone about all your products. Not many have heard of them like myself so they are very interested. Thank you from the bottom of my heart.

 by Andrew M.
Does exactly what it says

Works great. Highly recommend.

 by Phil M.
2 years later, still no leak

I used your 2-part Cooling System Repair #1150.  I bought a 15-year-old Ford Ranger with 135,000 miles. The water pump gasket had broken down, I used this product and 2 years later there is still no leak.

 by Dennis L.
Got me to my campground, fixed overheating

I had a radiator leak in my 1983 Nissan Sentra while heading out on a camping trip. Halfway to the campground, my car started to overheat. I got to (then) Kragen's Auto. I picked up a bottle of Bar's Leaks cooling system repair, topped off the radiator with coolant. Made to the campground and back home with no issues of overheating.

 by John S.
Live saver



Keep Up the Good Work!  Thanks Again!

 by William M.
The only product I will use

I have used Bar’s Leaks Cooling System Repair (#1150) as well as other Bar's Leaks products on various vehicles for about 50 years. It is the best and only product I will use.

Page 1 of 3:

FAQ (click or touch to expand)

Product Videos

SDS/Technical Info

SDS Left SideOpen
SDS Right SideOpen
Product Data SheetOpen