It works

Been using it since forever, never let me down.

Fantastic product

Fantastic product, delayed the need for head gasket replacement over 2 years with a single use.

No more leaks and back on the road!

I want to give you folks a compliment, I own a 1957 Packard Clipper that is a survivor, never being restored. The radiator (never been serviced or replaced) developed a top tank leak. I stopped by my local auto parts store and told them what was going on and they recommended Bar’s Leak Liquid Copper.

Let me tell you that this stuff is AWESOME!!!! No leaks and back on the road!

Kept my diesel generator running after hurricane damage

We were hit by Hurricane Ida on August 29th, 2021. We spent 14 hours in hurricane force winds. The wind blew debris, which made many pinholes in the radiator of my diesel generator. I spent 3 days babying my generator, checking it every 2 hours, day and night, and adding water to keep it from overheating. O’Reilly’s auto parts finally opened up around the 1st of September. I bought your Liquid Copper permanent cooling system block seal. Without reading the directions, I added way too much of your product. It almost plugged up my radiator. I took it out and flushed the radiator. I then added the correct amount of the Liquid Copper and filled the system up with coolant. It worked great. My radiators leaks went to almost nothing. I could sleep through the night without having to check the generator every 2 hours. We spent 20 days running on generator. We finally got line power back on September 17th. Without your product a bad situation would have been much worse and I would have gotten a lot less sleep. Thank you for a great product.

A product that does what it says it will do

Just wanted to let you know that I recently purchased and used your block seal liquid copper product on my 2005 Ranger and the head was leaking pretty good. I followed the two part instructions and it completely sealed the head leak. I appreciate a product that actually does what manufacturer said it would do, thanks.

Definitely worked for me

I have a 2007 Crown Victoria P71. Intake manifold starting leaking in two locations. Cost to repair would have been around $600.00. Bought a bottle of Liquid Copper back in November. It has been about 4 months. So far so good. I did not expect these results. May not solve everyone’s problem, but definitely worked for me.

Just follow the directions and let the product work

I have used Liquid Copper Seal (1109) successfully in several autos that had blown head gaskets. My experience has been that if the gasket leak is not too severe this will usually solve the problem. It is surely an affordable alternative worth trying. Just follow the directions and let the product work.

Quite effective

I have used Bar’s Leaks Radiator Stop Leaks on three occasions, and I have recommended Bar’s Leaks Radiator Stop Leak with the liquid copper crystals to numerous customers shopping at Advance Auto Parts, Store #7041, 2543 west 12th Street, Store #5323, 6000 Peach Street, Erie and the Harborcreek store, the Edinboro Store in Washington Township, and the Girard Store, in Girard, PA over the last eight years. I advised the customers there is a warranty, to keep the receipt, and I have never had any complaints about the use or sale of Bar’s Leaks Radiator Liquid Copper. I have also recommended the engine block and head gasket treatment from Bar’s Leaks to several customers and have used this product myself on a 2006 Nissan Frontier V6 engine with good results.    

I never had to do any remaining repairs after the use of these products. Simply follow the directions and they were quite effective.

Worked like it claimed it would

Bar’s Leaks helped with a problem I expected to have to pull the engine to repair. I had a freeze plug that did not seal correctly on a fresh rebuild on the back of the engine where the trans bolts up. It was weeping, not really leaking. Constant coolant smell when hot. I tried Bar’s Leak’s Liquid Copper Block Seal but really didn’t expect much. I was amazed that it took care of the problem without any drama. Worked like it claimed it would. It hasn’t leaked a drop in a few years now. I am usually very skeptical but based on this product’s experience I would definitely try another Bar’s Leaks product if needed.

Fixed friend's Impala

Hello, I used the Block Seal product. It was on a friend’s Impala that had a leak that was annoying him. I suggested your product that I have used in the past. Poured it in and he hasn’t had an issue since. Great products!

Car repair

I’ve used this on emergencies while driving work in the oilfield. Saves me money and time before costly repairs when a mechanic shop is nowhere near.

Best stop leak I've used and you will ever find

Without a doubt this is the best I have ever used. In various vehicles I have tried my variety of stop leaks and decided to try this product from Bar’s Leaks long ago. So far it has permanently solved leaks in several heater cores (ours as well as friends I have referred) also 1 radiator and 2 intake gaskets on a GM engine which always leak.

Unless you have a gaping crack in a head because you already overheated your car, or you have a crack in the plastic ends of your radiator, this stuff will save you. Obviously it will also NOT fix a leaking hose.

Also, if you have already put 1 container in your car and still have a leak, you already have bigger problems than this can solve. Adding another bottle will only make matters worse.

Liquid Copper

Works exactly as advertised! Im blown away by the almost instant fix this product worked on my severely cracked radiator. My front end was damaged by another motorist in a collision, I was filling the radiator every 5 miles! I just hoped this product could buy me some time ’til payday, but since using Bar’s Leaks I haven’t had any more problems!

Block Seal, It's a miracle

My 2000 Ford Ranger had a bad head gasket to water jacket to oil channel and compression leak as well a a perforated radiator, figured “what the hell, I’ll give it a shot before I tow this rust bucket to the junk yard”. I picked this product up at Oh Oh Oh O’Reilly’s and just in case stopped by Saint Alfonzo’s and got Father O’Callahan, funny name for a Nigerian priest, to bless the bottle and sprinkle a little holy water in it, hedging my bets I lit some incense at the Buddhist Temple on the way home. Following the directions I let the engine cool completely down, popped the radiator cap and poured in the whole bottle of Bar’s Stop Leak Block Seal Copper then topped off the radiator, which wasn’t easy ’cause the water was running out of the holes in the radiator pretty fast. Started the engine and within a couple of minutes the radiator stopped leaking and within ten minutes the formally rough running engine was purring like a kitten. Let it go for the full 15 minute warm up recommended on the bottle then took the old gal over to the Dyno’, I had picked up and extra 24-1/2 HP and the MPG was up a good 30%! Either this product is a MIRACLE or it is just my lucky day! Woo-hoo, I’m off to buy a lottery ticket and some Viagra and heading downtown!

1109 product

I just bought Bar’s Leaks 1109 radiator repair for gaskets and sealer. I poured 1 bottle on a v6 engine Nissan Frontier the problem is losing a lot of coolant and going to tailpipe. I’d run the engine idle for 15 min as instructed in the bottle , after that let cool down and add anti freeze and drove for 20 miles. The steam coming out of the tailpipe is gone. Now I need to drain the oil due to moisture. My engine runs smooth now just like new tune up. Will recommend this product.

Intake Manifold Leak- Liquid Copper

“Thank You” for making an awesome and effective product!

Recently, my 1997 Ford Aerostar van with the problematic 4.0 liter engine began moderately leaking antifreeze from the intake manifold. After coming to the conclusion that a repair would cost more than the value of the van, I decided to try the Bar’s Leaks Liquid Copper. I called you guys and your representative informed me that Liquid Copper was one of your best products so I decided to give it a shot. I flushed out my radiator and refilled with fresh antifreeze and a bottle of Bar’s Leaks Liquid Copper. The leak was initially active when I started the vehicle but it sealed a few minutes later as soon as the thermostat opened and the engine approached operating temperature. I then drove the vehicle on a 3 hour road trip and successfully made it to my destination and back home again with no issues. I use this vehicle for a traveling Top 40 Variety band which means we are always on the road traveling in the late hours of the night into early morning. Many miles have passed since adding your product and my 1997 Aerostar is still going strong and has not leaked a drop of antifreeze since adding Liquid Copper into my radiator.

Thank you again for making a reliable and affordable product. I can now say from experience, your products do work as advertised and there is a reason the Bar’s Leaks company is still in business and prospering after all these years.

Keep up the great work !

Love your product

I have been using your product for years and last night my truck lost all it’s coolant. I told my friend to bring me some water and a can of Bar’s Leaks and once again your product worked and I was able to drive the 342 miles to my house and still drive it. Love your product. THANKS BAR’S LEAKS.

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.

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.

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.

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.

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.

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!

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!

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!

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!

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.

I have a 1998 Chevy Monte Carlo with those leaky intake gaskets, rather than spend a lot, I used 1 bottle of your Liquid Copper product and the water leak into the intake stopped so fast I couldn’t believe it. I’ve been putting up with that slight leak and over-heating for about a year but no more. Thanks.

Recently my Ford Windstar was diagnosed with either a blown head gasket or a crack in the cylinder head. Faced with the prospect of an expensive repair, I was relieved when my radiator man, a very honest person whom I have been doing business with for over twenty years, informed me of a new Bar’s Leaks product that might be my savior. He installed a bottle of your Liquid Copper product, which he referred to as liquid glass, and my coolant loss problems have disappeared. I am here to tell you thanks for making such a wonderful product and for saving me thousands of dollars in repairs. I tell all of my friends about my predicament and how your product has helped me. Thank you again.

I have a 2005 Land Rover LR3 and I consider myself very caring for it. Well, it developed a leak in the intake manifold and a small leak at the thermostat housing. Total for mechanical repairs would have cost me over $400 for parts and an entire weekend. Used Bar’s and the leaks are all gone. Saved me!

I am a fairly good mechanic. Good enough to do engine rebuilds (not simply change-outs), transmission rebuilds, front end repairs, clutch & drive line overhauls, brakes & suspension, electrical & computer diagnostics, emissions & safety inspections, and any other mech/elec “fix” on cars from late-model to antique. It’s my hobby. I have a Subaru that was transferring coolant regularly from the radiator to the reservoir tank and not going back causing fluid loss from the over filling tank. Every couple of days I manually replaced the reservoir coolant back to the radiator. Very annoying. Diagnostic work (engine compression test, cooling system pressure test – holding 15 psi for 24 hrs, spark plug inspection, infrared thermostat check, reservoir with hose leak check, radiator cap test and new replacement) yielded nothing. Everything was as it should be with no leaks. Baffled, frustrated and desperate, I tried Bar’s Leaks ‘Liquid Copper 1109, Block Seal’, which I believed would NOT WORK because “Fixes in a Bottle” seldom do … or so I thought. I was WRONG! Bar’s Leaks WORKED! I still don’t know what the problem was, but it’s fixed. It hasn’t lost a drop in several months.

I have a 1999 Pontiac Bonneville 189K. Had a small cooling leak. Had car in for service and stupidly agreed to a coolant leak test which caused a material upper intake leak. Knowing I will not attempt to change the intake gasket at this time, I gave your copper seal product a chance. Fantastic!! I used it last night after purging some coolant, finished up and rinsed the engine with warm water. Ran the car for about an hour, engine was dry as a bone!! Coolant is up and pressured. Great product!

Seein’ is believin’ guys! I was skeptical about Liquid Copper to seal a radiator housing leak of my 1.6l 4cyl w/AC 2001 Daewoo Nubira, and had even accounted for some bucks for Plan B. I refilled the return container with new coolant, started the engine and waited until the refrigerant was warm and poured half bottle, then waited for some seconds until the copper particles leaked through the gap, poured the rest, replaced the radiator expansion tank with the pressure cap, and goodbye Plan B, Liquid Copper made it!!. I left the engine to idle for another 20 minutes and not a single drop leaked anymore. Thank you Bar’s Leaks for such a good product, I bought two more bottles to be carried in my 4×4, just in case or to help someone else in trouble. BIG THANKS!!

ALL I can say is that it’s a miracle!!! Too good to be true! You guys really did it this time!!! Had a blown head gasket on an ’86 Toyota PU, burning coolant badly, and coolant in oil, after running for about 30 minutes it did its thing and engine started running again. Tips on YouTube said to remove Tstat, and offending cylinder spark plug, which I was just too lazy..Tsat would have been a good idea.

Bottom line it’s fixed and I’m shocked! Lastly TIP, if you burned A LOT of coolant over a few days, etc. you MIGHT have clogged your catalytic converter, that once happened to me YEARS ago and not even the best of mechanics could figure it out, had back pressure and the engine was struggling to run, so remember this! Great product and I am recommending.

I own a 2002 dodge Durango with the 4.7 liter. It was constantly running hot before replacing the entire cooling system and still running hot after. I did some research and found the problem to be defective head gaskets. I was referred by a online post to try Bar’s Liquid Copper and I was amazed by the result. I have been a mechanic for many years and have tried many leak stop additives and none ever worked. This stuff is great it saved me a head gasket job.

Tried many many products over the years and this stuff truly works as it says it does. Just sealed a BB-sized hole in radiator with out having to add more than the directions. Hats off to you Bar’s Leaks. Incredible product.

I’ve used the Bar’s Leaks Block Seal Liquid Copper on many vehicles. Usually for leaking intakes, and had very good success with radiators as well. I was born and raised on a farm, and my Dad was very old school. He always used Bar’s Leaks on old tractors and combines and various other kinds of equipment. I ask him as I became older why he only used Bar’s Leaks on radiators when there’s so many different products out there now. He said its simple…it works. Plus we usually don’t have to replace the radiator in the off season do we? That’s all he had to say to convince me, and I’ve used Bar’s Leaks products ever since. I usually don’t go on and on about products, but Bar’s Leaks has worked and been used by my family on our farm for many years.

2012 Ford Fiesta. This stopped milky oil and smoke on the first day. Now family can roll again.

This product is amazing. I have a 2002 Dodge Durango with the 4.7 liter engine, which constantly ran hot even after replacing entire cooling system. I later found out it’s a defective head gasket. I was recommend by a post on a Dodge forum to try Bar’s Leaks Liquid Copper. I purchased a bottle and followed instructions on bottle and, wow, within 30 minutes of driving no more running hot. Thanks for a great product.

Had a very small leak some where in the rear of the engine (1998 Ford Ranger). The very small drip would end up on the bottom of the oil pan between the pan and the transmission. Pulled coolant out of the radiator and added the Block Seal product. Stopped the leak almost immediately! We’ll see how long it last. Bought at WalMart for less than 8 bucks.

Thank you so much! I have an ’05 Ford Freestar that was blowing through a gallon of coolant daily. 12 years old and 194,000 miles, I could not justify the 1200 dollar repair so, I happen to be at Walmart and saw your product. It was a Christmas Miracle! So far so good. Holding coolant and have heat again! Used the head gasket and heater Liquid Copper product. Again, thanks for a great product. Although the mechanic I had spoken to tried desperately to convince me it was bad for my vehicle. Probably because he knew he had a large payday coming. Not today!????

Just added the Liquid Copper to my coolant. So far no leaks, very happy!

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.

My ’94 ford Taurus was leaking water between the transmission and oil pan. I couldn’t see where it was coming from. I put the Bar’s Block Seal Liquid Copper in it and within 10 minutes it stopped the leak. Saved me money and time, you guys rock.

I have a 2001 Mercury Mountaineer 5.0 V8 153,000 miles and counting. Last week it overheated at idle so I filled the radiator up. Overheating stopped. But the next day vapor (steam) and water dripped out of the tailpipe. A/C struggling to keep cool even after a shot of refrigerant. Radiator leaking some, low coolant level but no visible radiator leak. Fouled plug in #8 cylinder slight rough idle/misfire. Bingo! Leaking gaskets! Got Ba’rs Leaks head gasket sealer and Bar’s Leaks oil additive. No more leaks, smooth idle and the A/C blows ice cold. I think my culprit was using a fuel injector cleaner that messed up my engine seals it being a high mileage vehicle. BTW I change engine oil like clockwork. Thanks Bar’s Leaks!

This product honestly saved me $500 and probably more. I’m so glad that I found this product and would gladly tell other people to purchase this product if they needed it. Like I would let you guys pay me to drive around with a giant Bar’s stop leak sticker just because this product is so good.