Head Gasket Sealant (1100)

Head Gasket Sealant


  38 Reviews

How does the need for a block & cracked head sealant come up in the first place? Usually by overheating, which can be caused by a damaged head gasket, cracked head or a leaking block. Bar’s Leaks Head Gasket Repair eliminates this problem — guaranteed. This product contains a blend of aramid and refractory fibers, which provide the strength of a bulletproof vest and the heat resistance of fireproof clothing. As these particles penetrate a crack or the blown head gasket area, they lock together and bond, forming a hard, permanent ceramic-type seal.


WARNING: Head Gasket Sealant is NOT COMPATIBLE with antifreeze and must only be added to the cooling system after ALL ANTIFREEZE has been flushed and removed.

DANGER: Opening the cooling system while engine is hot or running may cause severe burns.

DISPOSAL: Observe local laws & regulations. Where permitted, dispose of in sanitary sewer system. Never pour on the ground or in a storm sewer system.

NOTE: Protect from freezing.

  1. Engine must be cool enough to safely open the radiator cap. (This could take 30 minutes or longer). Drain and completely flush antifreeze from cooling system and overflow tank. Using a flush “T” with garden hose works best. If cooling system is dirty, use a good quality flush following manufacturer’s instructions. ALL antifreeze must be removed or clogging may occur.
  2. Shake well. Mix Head Gasket Sealant in a bucket or container with approximately 3 quarts of warm water. Pour this mixture directly into the radiator. If using in a small cooling system, including all 4 cylinder engines, mix ½ bottle of the Head Gasket Sealant with the warm water. TIP: If you do not have access to your radiator and vehicle has a pressurized reservoir, then product can be added to reservoir. If not then remove top hose where it connects to the top of radiator and install product in hose. Reattach and tighten clamp.
  3. Fill cooling system with water and reinstall radiator cap.
  4. Start engine, turn heater on hot and fan on high.
  5. Run engine for 10 minutes or until thermostat opens.
  6. Turn vehicle off and allow engine to cool. Allow enough time so it is safe to open cap.
  7. Top off (fill up) cooling system with water and reinstall radiator cap.
  8. Run engine at idle until normal operating temperature is reached. Continue running engine at idle for 15 minutes.
  9. Turn vehicle off and allow 45 minutes to cool.
  10. Top off cooling system with water as needed and reinstall radiator cap.
  11. Run engine at idle until normal operating temperature is reached. Continue running engine, but at high idle (approximately 1200 RPM’s for vehicles with a tachometer) for 20 minutes.
  12. Turn vehicle off and allow engine to cool for 1 hour. TIP: For vehicles with intermittent or very minor leaks, it is recommended to follow step 12 by idling vehicle for one hour.
  13. Remove radiator cap and drain system.
  14. Leave drain open and radiator cap off for 12 to 24 hours. If temperature is below freezing, vehicle must either be kept heated or immediately go to step 15.
  15. Flush entire cooling system and refill with manufacturer’s recommended antifreeze/water mixture.

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At Bar’s Leaks, we employ a team of top-flight chemical engineers who specialize in solutions such as these – in fact, we are the national leader in chemical head gasket repair solutions. Each product, our cracked head sealant included (aka blown head gasket), is custom-designed to be effective, affordable and easy to install. You don’t need any special automotive expertise — you just need to be able to pop and lift your hood. The rest is about as simple as any car maintenance can be.

Forget that repair bill. Simply use this product and get back on the road and back to your daily routine in no time — with several hundred extra dollars in your pocket.


Your car belongs on the road. Don’t let minor or even moderate leaking issues keep you from the convenience and joy of driving. Trust Bar’s Leaks for cylinder head leak solutions that are fast, easy, effective and affordable. Since we first began serving automobile owners nearly 70 years ago, we’ve been committed to delivering products that anyone can use. When you choose Bar’s Leaks for cracked head sealant or products related to leaking cooling systems, engine oil, power steering, transmissions and more, rest assured you’re getting a product that will work and is easy to use.

Not all products that claim to be cracked head sealant can be counted on for performance, and some of these products can even make your issue worse. When you want cylinder head leak repair solutions that are time-tested and proven to work by millions of customers, choose block seal products from Bar’s Leaks. Made in the U.S.A., just an hour from Detroit, Bar’s Leaks is the number one provider of block seal products that get the job done time after time.

Get your cracked head sealant today and fix your head gasket problem affordably.


Customer Reviews

  38 Reviews
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 38 reviews
 by Chris
Bars head gasket sealant

I used this stuff and it worked great. I was scepticle at first. I used this stuff about a month ago. I had exhaust coming up through my expansion tank. It would cause my coolant to boil almost immediately. Well not immediately but after about 10 minutes. I followed the directions exactly how the bottle said and it worked. I see a lot of reviews about people putting this stuff in without flushing the radiator. I mean it say right on the bottle that its not compatible with coolant. Or it sounds like most people don't have the patience to go through the steps completely. Or correctly. And then write a terrible review. This is an awesome product. Any negative feedback is from user error. There's a lack of being able to follow instructions relative to every negative review. I have a beat up worn out broken 2002 Nissan Sentra. It was ready for the junk yard. This stuff did exactly what was advertised. Did a perfect job on fixing my problem. Its been about a month now with no negative consequences. Will use again. I would feel safe to use this my mother in laws vehicle. And guys we all know the dangers of working on the mother in laws car

 by Greg C. - Ventura, CA

Bottom Line: I'd like to congratulate you guys for making something in America that completely, completely works.

 by Earl Ward - Augusta, GA

I don't know who developed Bar's Leaks Head Gasket Repair, but I'd take a bullet for the guy! I've always sworn by Bar's Leak products so when the oil turned milky in my '91 Chevy conversion van, I got a bottle of Bar's Leaks Head Gasket Repair and followed the directions to the letter. It was the best use of two days mechanicing I can remember. Thanks for another great product!

 by Scott Adams - Johnstown, OH

Your head gasket repair product saved me over $1,000 in repairs on my 2004 Impala. It worked exactly as advertised, great product.

 by L. H. Warner - Tulsa, OK

I had a head gasket blown on my 1992 Chevy Lumina; it was going to cost me about $600.00 to $1000.00 to fix it. I bought a can of your product Head Gasket Repair & Block Seal, that only cost me 9.95. It fixed the head gasket. I saved a lot of money, Thanks to your product.

 by Y. H. - Homosassa, FL

Last month driving to Oregon from Florida, my car blew a head gasket in Hermiston, Oregon. I put Bar's Head Gasket Repair in my 1996 Acura. I followed the directions EXACTLY. I drove on to Portland, Oregon and then back home to Tampa Bay, Florida. My car worked perfectly. My car now has 288,000 miles on it. Bar's Leaks is the greatest!

 by J. L. Lake Wales - Ft. Lauderdale, FL

I have a 1996 jeep Cherokee with a 4.0 liter, with 233,000 miles on it. I blew a head gasket, and had the Jeep towed home to fix it, after taking the head off I discovered a bad #6 piston, after waiting a week for all the parts to come in and reassembly, (basically a in frame overhaul) after starting the engine and testing the engine, due to defective head gasket or a crack in the #6 bore? Water was in the oil. Upon the disappointment and all the time and money I spent on my Jeep, and knowing what the wife was going to say, “I told you so!!" I remembered that there was a chemical to repair head gaskets without having to pull it apart again, so I went and got your block seal from Advance Auto Parts. Your product was $10.00 and it worked!!! You saved me so much you can't begin to even know how much! Thank you for your sealers that really work!

 by F. R. H. - Coquille, OR

I've read several of your testimonials for your Bar'’s Leaks Head Gasket Repair and would like to add mine. Our kids in Vernal were having a problem with their 1999 Suburban overheating. They stopped driving it when they noticed that the oil color had changed. So on a recent visit, I checked it out. The oil was three inches high on the dipstick and looked like crème cappuccino. The 350 V-8 at idle sounded like a washing machine. The kids had been adding water to maintain the radiator fluid level and didn'’t realize they were filling up the crankcase with water! I'’ve always had good luck with your products when it came to radiator leaks. With a new baby arriving that day, the kids were in no position for a $1500 head gasket replacement. So we looked up your products online and then took a trip to the store for Bar’'s Leaks Head Gasket Repair. I followed all the steps carefully, flushing the coolant system under idle, using a coolant system cleaner, removing all antifreeze and then adding Bar’'s Leaks Head Gasket Repair and running as instructed. When I drained the crankcase, more than two gallons of fluid came out! It took two oil filters and three oil changes to get the oil to run clear. I let Bar’s Leaks Head Gasket Repair set up overnight in an empty system, and then added all fluids to specifications the next morning. Since then the Suburban has been running smoothly for several hundred miles in hot weather, and both the oil and coolant systems have maintained their proper levels and composition. I just got a call from another son-in-law who has a blown head gasket. Guess what I'’m recommending!

 by J. K. - Russell, IN

I purchased an older vehicle and right after I bought it I blew the head gasket. The mechanic quoted me over $1500 to repair it. That was almost as much as I paid for the vehicle. I was browsing online and noticed the Bar's Leak head gasket repair. I purchased it for around $15.00 and utilized it. That was over 8 months ago and I have yet to overheat. I was concerned with the summer and running the air conditioner. This product was a god send. Not only did it work but saved me a fortune on vehicle repairs. Thanks for making this product.

 by J. H. - Scottsdale, AZ

I have been a used car broker for 39 years and have bought and sold thousands of vehicles, many of which were in need of repair. Last month I bought a 2002 Buick Regal with a 3.8 L V-6 from the local auto auctions. It overheated on the way home and I had it towed to my mechanic. Th next day I got the bad news - Blown Head Gasket, $1200.00 fix! Well, I had to go to Autozone for something and saw your headgasket sealer display. I said what do I have to lose and picked your Head Gasket Repair product. I took the bottle home and followed the instructions exactly all along expecting no good results. To make a long story short, the car ran perfectly within 3 hours. I put it in the newspaper the next day and believe it or not sold it to another auto broker for a good profit! You made a believer out of me with that product and saved me $1200+. Thank you and I'll always tell my many dealer friends about your product.

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