Liquid Aluminum (1186)

Liquid Aluminum


  29 Reviews

Bar’s Leaks Liquid Aluminum is part of our next-generation stop leak lineup that not only seals leaks, but also conditions the system. With this formula, you’re getting a solution to your immediate problem plus a preventive tool for avoiding future issues with heater core leaks and coolant leaks. This product also contains Xtreme Cool™, which stops overheating and significantly decreases water temperature. The combination of these two elements are guaranteed to safely and easily seal leaks in plastic, aluminum and metal radiators, heater cores, gaskets and freeze plugs.


  1. Allow engine to cool. Make sure engine is cool enough so radiator cap can be safely removed.
  2. Shake well. Pour Bar’s Leaks Liquid Aluminum directly into radiator. One bottle treats systems up to 4 gallons. Use 1/2 bottle in 3 and 4 cylinder engines. TIP: If direct access to radiator is not available, install in overflow tank.
  3. Fill radiator and overflow tank to proper level and reinstall radiator cap.
  4. Drive/idle engine for 15 to 20 minutes. If leak continues, second application may be required or mechanical attention is needed. For severe leaks, like a blown head gasket, it is recommended to use Bar’s Leaks Head Gasket Fix or Blown Head Gasket Repair.
  5. Leave Bar’s Leaks Liquid Aluminum in cooling system for continued protection.

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Some of the best recipes only require two key ingredients to make them the favorite dish at the dinner table. We might not have professional chefs at our company, but we do have a powerful team of product engineers who constantly experiment to give you the best stop leak products in the industry. And that’s exactly what happened with our Bar’s Leaks Liquid Aluminum Cooling System Radiator and Heater Core Stop Leak.

The two key ingredients in this product are Liquid Aluminum™ and Xtreme Cool™. Liquid Aluminum™ is part of the next-generation stop leak line that not only seals leaks, but also conditions the system. When you choose Bar’s Leaks to stop coolant leaks, you’re getting a solution to your immediate problem plus a tool for avoiding future issues with heater core leaks and coolant leaks. It also contains Xtreme Cool™, which stops overheating and reduces water temperature. The mixture of these two technologies are guaranteed to safely and easily seal leaks in plastic, aluminum and metal radiators, heater cores, gaskets and freeze plugs.

Go to a mechanic for these same services and you’ll discover just how much Bar’s Leaks delivers in the way of value. A professional mechanic will charge significantly more for heater core leak repair and mitigation of coolant leaks. You’ll also have the inconvenience of finding time to take your car to the shop, get an estimate and wait for the mechanic to repair your coolant leak. It’s an inconvenience you can do without when you discover the power of Bar’s Leaks and our coolant leak repair products.

Many who use our heater core leak products are amazed by the benefits. That means that the next time you notice your radiator is leaking, all you have to do is grab one of these bottles, open the hood of your car and follow our how-to video for the quick and easy installation process. It’s time to get your show back on the road. And Bar’s Leaks can get you there by quickly, effectively and inexpensively helping you stop coolant leaks.


You use a car for convenience and transportation. Professional repairs can be inconvenient and expensive, which is why Bar’s Leaks has spent nearly 70 years developing products that fit squarely into your lifestyle and budget. Our team of award winning chemical engineers has spent decades perfecting products that stop coolant leaks, stop heater core leaks, and address a range of other automotive problems. These chemical repair solutions are proven to work, and our team is always innovating and searching for new ways to better serve today’s car owners and the latest generation of automobiles. All our products are made right here in the U.S.A., just an hour outside of Detroit. Take advantage of Bar’s Leaks products when you need to stop coolant leaks, and discover just how fast, effective and inexpensive the solutions can be.

Find out where you can get Bar’s Leaks to stop your cooling system leak today.

Customer Reviews

  29 Reviews
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 29 reviews
 by Steven B.
You guys keep us on the road

I've been using Bar's Leaks products for years. I learned about them from my grandfather most recently. I use it in my 1997 Ford expedition. It had a minor leak in the radiator and I was quoted over $600 to repair. I use the Liquid Aluminum radiator stop leak and the problem was solved in less than 5 minutes. In the time it took me to drive from my house to my work. The leak was completely stopped. I can't say enough about these products. I recommend them to everyone and if anyone has a leak that they need taken care of, I use these products to fix their car. Keep up the good work guys. You're keeping us on the road. Your products are making it so we don't have to buy new cars or parts all the time. Thank you guys!

 by Alyssa W.
Stopped my Jeep's leaking

I used the Liquid Aluminum Radiator and Cooling System Fix #1186. I had a leak in my radiator on my Jeep Liberty and the product worked and it stopped leaking until I could get a new radiator.

 by Tim W.
Stopped leak completely

I used Bar’s Radiator Stop Leak Liquid Aluminum 1186 I think is the part number. I had a slow leak in my radiator, and it stopped it completely.

 by Tom S.
Problem solved very quickly

This is a review for Bar's Leaks Radiator and Heater Core Stop Leak, aka Liquid Aluminum.

Water was coming out of my tailpipe, so I added a bottle to my radiator fluid and the problem was solved very quickly.

 by Joe K.
Bar's Leaks products have always worked for me

Two years ago, I used the head gasket Bar’s Leaks on a nice old 1978 Allis Chalmers forklift I purchased for $1000 because it clearly was leaking into the cooling system, the water was milky and was lacking power, which is the telltale sign of a head gasket leak.  I tried it, followed the directions and it has been fine since!  It idles well, doesn’t overheat now, has power and the water in the radiator has been clear since. 

I have had success over the years with this same product as well on other cars.  35 yrs ago, one of the first cars I had was a 1978 Chevy Nova with a 350 engine that had a head gasket leak and put it in and that fixed my problem as well, the gasket didn’t leak anymore.    

Lastly, I had an old pickup, again, 35-40 yrs or so ago that had a small pin hole leak in the radiator, I really didn’t have money then to replace it, so I gave the Liquid Aluminum sealer a try and sure enough, it fixed it!  I remember seeing where the pinhole was and it kinda looked like silver solder had flowed out of the radiator and sealed it.  Again, good stuff that worked for me.

 by John F.
Still sealed 2 years later

The seal for the water pump in my V12 Jaguar engine was damaged near one of the bolts. Tightening it had no effect and replacing the seal would require a time-consuming removal of a number of components - so, as a shot in the dark I tried the Bar's Liquid Aluminum. I really did not expect the leak to stop, but it did, and is still sealed more than 2 years later. The 5.3L Jag engine is a real heat-producing unit, so for the leak to stay sealed is a great testament to the Bar's Leaks products.

 by Eric A.
Saved me big money

I used the Liquid Aluminum (1186) and it really worked! 

Our minivan, 2010 Chrysler Town and Country had a slow leak but the smell of the coolant goes inside the cabin. Before doing an expensive repair, I tried using the Liquid Aluminum Heater core and Radiator Stop leak. After using it, it has been 2 years and no leak or smell. This product saved me costly repairs!

 by Keith Coalter
Bars leak coolant sealer

My radiator was leaking around the tank. After adding Bar's Leaks to the radiator, no more leaks! Stuff works excellent.

 by Jason Ibbetson

Worked from the first application, has been over three months and no sign of a leak.

 by Erin Petrick
Liquid Aluminum Radiator Stop Leak

2008 CR-V 170k miles. Small leak somewhere. Trans cooler line I think. Put half a bottle Liquid Aluminum Radiator in 8 months ago. Leaked a few times over the next 2 days but then stopped.

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