Liquid Copper (1109)

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Liquid Copper (1109)

What does it do? Our formula permanently repairs larger leaks in radiators, intake manifolds and gaskets, heater cores, blocks, heads and freeze plugs. It contains an antifreeze-compatible sodium silicate liquid glass formula, so no draining of the cooling system is required. Not to mention, it will not harm the cooling system when used properly. The intake gasket seal you’ve been looking for is far more effective, easy to use, and less expensive than you’ve ever imagined. This is why Bar’s Leaks exists: to offer usable, low-cost intake gasket seal and other products to auto owners who have no special experience or expertise. We've been doing this for over 70 years, so we know a thing or two about chemical repairs. Contact Us About This Product Find This Product Near You

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  • Can Bar’s Leaks® Liquid Copper™ Intake & Radiator Stop Leak be installed in existing antifreeze?

    Yes, unlike other copper stop leak products, Liquid Copper™ One Step sealer contains an antifreeze compatible sodium silicate formula, so draining of the cooling system is not required as long as manufactures recommendations are followed. It also can be used in water alone however, a second bottle of Liquid Copper™ is recommended to be added to the system once antifreeze is installed.

  • Will it work in the new extended life antifreeze?

    Yes, Liquid Copper™ is compatible with both conventional green or blue (silicate-based) and extended life red/orange or yellow (OAT/HOAT) 50-50 mix antifreeze.

  • Do I need to drain my cooling system after using Liquid Copper™?

    No, this product is designed to be left in the cooling system to protect from future leaks.

  • How does this type of product work?

    It stops leaks by forming a physical plug with organic and synthetic fibers, copper and an ionic modified mineral. The plug forms as the coolant and sealer flow out of the leak. A wetting agent cleans the sides of the hole and prepares the surface for bonding. The first fibers catch on the side of the leak or hole eventually bridging the entire hole. The fibers now act as a sieve trapping more fibers, copper particles and minerals, creating a composite plug. This plug is stabilized or cemented with a liquid glass. The liquid glass hardens with increased temperature and completes the seal.

  • How long does it take to see results?

    Results should be noticeable within 20 to 30 minutes. If the leak is not sealed in 30 minutes of running, mechanical repair may be needed.

  • What are the dosage recommendations?

    Use 1 (one) bottle for regular size cooling systems, this covers most 4, 6, 8 and 10 cylinder engines. For small cooling systems, such as 4 cylinders with no air conditioning, use 1⁄2 (half) of bottle. For other small systems use approximately 3 ounces per gallon of cooling capacity. In larger systems, use 1 (one) bottle for every 6 gallons of cooling system capacity.

  • Will Liquid Copper™ plug my heater core?

    No, Liquid Copper™will not plug a clean heater core. Note: If using Bar’s Leaks® to stop heater core leaks, make sure you turn your heater control to HOT. Some vehicles have a valve that controls coolant flow through the core and is only opened in the HOT position.

  • Can I install Liquid Copper™ in my overflow reservoir?

    For best results Liquid Copper™ should not be installed in a regular overflow tank unless it has a screw on pressurized cap. If you do not have access to your radiator, remove top hose where it connects to the top of the radiator and install product in hose. Reattach hose and tighten clamp.

  • Will this work in both domestic and import cars and trucks?

    Yes, Liquid Copper™ will work in all types of water cooled vehicles.

  • I accidently added the Liquid Copper™ into my gas tank, what should I do?

    Liquid Copper™ is only designed to be added to the cooling system. If the product is accidentally installed in the gas tank, the tank should be removed and cleaned out by a professional mechanic.

  • I accidently added the Liquid Copper™ into my engine oil, what should I do?

    If the product is accidently installed in the engine oil and the engine has not been started, in many cases you can remove the valve cover where installed and drain the oil leaving the drain plug off. Then use an engine flush washing out the head giving special attention to the oil return holes that run down to the oil pan. Clean these out and pour the engine flush down these holes flushing everything into the oil pan and out the drain hole. If the engine has been run, the vehicle needs to be towed to a professional mechanic for evaluation. This might include taking the engine apart to clean all of the internal parts.

You’ll find plenty of options when searching for products to fix an intake gasket leak. While our competition may claim to stop the leak quickly, their products don’t always perform as advertised and they sometimes make things worse. Their stop leak products can’t get your car back on the road like Bar’s Leaks — that’s why we’ve been the most trusted stop leak brand since 1947. Throughout our long history of serving car owners like you, we’ve used a team of dedicated chemical engineers to constantly develop and refine products that are safe, fast and effective in stopping intake gasket leaks and other automotive problems — including liquid copper and much more. Make sure to watch Bobby and Caitlin in our handy how-to video so you can become a “three-minute mechanic” and finally take control of that leak.

Stop Leaks, Save Money

When you’re experiencing mild to moderate leaks, including intake gasket leaks and leaks related to power steering, engine oil, cooling systems, transmission and other key systems, in your car’s operation, Bar’s Leaks has the power to stop those leaks quickly, effectively and affordably. As the best-known stop leak brand in America, we have a long history of creating products that even the novice auto owners can use to extend the lifespans of their vehicles and, best of all, save money by avoiding costly repairs. Our products are made in America, just an hour outside of Detroit. And we can look back at nearly 70 years of service and point to millions of customers who have used our products to their satisfaction. At Bar’s Leaks, you’ll find intake gasket seal in the form of liquid copper, plus other effective products, that fit perfectly into your lifestyle and budget.

Find where to get your Liquid Copper today.

Leave a Review

  • “I want to leave feedback... I used the Bar’s Leaks Copper Block Seal on my 2000 Caddy STS. Before I used this stuff my car could only run for about a mile before it started to overheat. I tried a couple of other fixes, the ceramic, the fiber which both made you flush your cooling system before you even added the crap. Then I used your Copper Block Seal and it worked. I paid over $150 for a treatment of the ceramic stuff and it didn't do anything, the fiber ceramic didn't do anything either. They were both a waste of money. Your Bar’s Leaks Liquid Copper Block Seal is the best s**t I have EVER used.”

    Michael M. - Columbus, OH
  • “I've used Bar's Leak several times over the years, but you have so many products available now that I really didn't know what to use. Thank you for recommending Liquid Copper Block Seal for the intake manifold leak on our 1999 GMC. It seemed to work immediately and hasn't leaked a drop. Good products, good website and great advice. Thanks again for your help.”

    E. C. - Southern Windows & Doors
  • “I had a head gasket leak that was requiring me to replace about a gallon of coolant every 2 days. After using only 1/2 of a container of your Liquid Copper Block Seal [because disconnecting the return line to the radiator, I could only pour in that amount], the problem vanished. At some point I do need to repair the head gasket, but your product has bought me some valuable time.”

    P. B. - Sunnyvale, CA
  • “Hello, I used your product with great success the last nine months. After a blown head gasket, I applied your product and it immediately sealed the leaks. Just today after checking my radiator reservoir, I noticed some very small copper-looking particles floating on top. There seems to be no water in the oil and no white smoke form the tail pipe. The car is running good and not overheating.”

    G. K. - Columbia MO
  • “I had a significant cooling system leak from the radiator on a 2001 Cherokee. I put in the Liquid Copper Block Seal Stop Leak, followed directions on the bottle, and.... NO LEAKS! I can't say enough about a product that delivers as stated. A plus is it’s made in the USA. I'm a customer for life.”

    J. L. - Bolingbrook, IN
  • “I was working on a friend’s car as a favor. After a full tune-up, the car still had a rough idle. I decided to take the car home where I could spend more time on it, I didn't get too far before the car overheated leaving me stranded on a bridge of a major highway. The car had a blown head gasket and would blow the coolant out faster than I could add it. There was no way I could use any of the other sealants that require flushing, adding the sealant, then flushing again. I bought one bottle of Bar’s Liquid Copper Block Seal Intake & Radiator Stop Leak. I didn't expect it to work at all, but it was the only thing that I could think of without having to fork out $150 to have it towed. I poured one bottle into the radiator, added some coolant and by the time I drove it back to my friend's house, it was running great. I couldn't believe it. The car is still running great. I can't even tell you how much trouble, time, money, and stress your product saved me. Thanks!”

    L. M. - Fairfield, WI
  • “Bar’s Leaks, I’'ve got to tell you that your Bar’'s Leaks Liquid Copper Block Seal must be some kind of miracle in a can. Instead of the $800 bill the mechanic said it would cost me just to find out why engine coolant was getting into the engine oil, not counting the parts yet, I spent $10 on your product. It immediately fixed the coolant leak, which was bad. Then I get a $5.00 rebate on top of that, which I felt guilty about even taking. I never had any faith in quick fix cures for machinery, but I do now in your product. Thanks so much!”

    C. D. – Skandia - Grand Haven, MI
  • “My 1999 Ford Ranger started losing coolant about a week ago, so I replaced the thermostat. That didn’'t work so I took it to a shop that told me I had a cracked block or blown head gasket and it would be $800 to $2000 to fix it. Since I have 140,000 miles, I knew that didn't make sense. I called my brother who is much more of a mechanic than me and he suggested Bar's Liquid Copper Block & Radiator Sealer. I put it in a couple of days ago and it has amazed me how well it has worked. The truck quit losing coolant, runs 100% better and I think I may get another 10,000 miles out of it at least. I have never written a product testimonial before, but then again I have never had a ten dollar product work that well to save me hundreds or thousands of dollars. Thanks!”

    C. Gill - Austin, TX
  • “1109 - Liquid Copper Sealer: I waited as the initial result was so great I did not want to jinx it. My 2000 GMC Jimmy started to leak coolant. At first from the location I thought it was the water pump, but then realized it was likely the intake gasket. I was losing about a pint in the overflow tank with a steady steam. Repair would be about $800, so I thought I would give Bar's a shot. Found the right product, added it as directed, and the drip stopped. Five weeks and 1000 miles later, system has remained at the same level, no leakage. What a great result. Thanks Bar's!”

    J. S. - East Williston
  • “I recently used your product 1109 block seal on my daughter’s 1994 Volvo 940 wagon. The car had a head gasket leaking at front of head left side when looking under hood. I had noticed anti-freeze level dropping very slowly and a film of oil in overflow tank but didn’t give it much attention until my daughter said her car wasn't running right. I found her radiator tranny cooler let go and contaminated and ruined her tranny. After we purchased a used tranny and had it installed, I noticed the head gasket problem. "WOW" Now I am beside myself. 150,000 miles on the car and 1000.00 tranny repair. I purchased your 1109 block sealer and it worked!!!!! She currently attends college 3.5 hours from home and reports are still positive. Thank you for making a product that works.”

    D. J. – Schuylerville - New York, NY