Head Gasket Sealant (1100)

Head Gasket Sealant


  49 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

  49 Reviews
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 49 reviews
 by George G.
You saved me a large expense

I purchased Bar’s Leaks Head Gasket Sealant part number (P/N) 1100 after receiving your email newsletter. In just a few days of using this product my 2011 Jeep Liberty is running great. No more misfires, or knocking, or antifreeze loss. I seem to feel more power in my drive too.

You have saved me a large expense, or possibility of getting rid of a vehicle that is still in great condition overall even having over 202k miles.

The reviews on internet were good when I researched my issue, and glad I went with your product. Would recommend 100%.


 by Larry M.
Recommended by mechanic

Good product! Recommended to me by my mechanic.

 by Jonathan B.
Other brands didn't work, yours did

I am a mechanic and we know mechanics don't like or trust easy fixes. I had an external head gasket water leak.

Your Bar's Leaks 1100 Head Gasket Sealant is keeping my Silverado 2500HD diesel running. I used another product that kept it going a year. I used other brands for 3 more treatments and sadly didn't work. I used yours and so far so good after about a month! Thank you!

 by Victor P.
It's been almost 4 years, no more problems

I used your Bar’s leak Head Gasket Sealant #1100 on my 1999 Chevy Silverado 2W drive. Coolant was going in the head gasket, and it was heating up. I used one bottle of the head gasket sealant and it fixed the problem. It’s been almost 4 years and my truck has not given me any problems anymore. Thank you.

 by Bob L.
Made my ride enjoyable again

I’ve used both the radiator stop leak as well as the head gasket sealant and was completely satisfied with both products as they solved the leaks and made my ride enjoyable again. 

Car - Audi A6

 by Ray F.
Thanks for keeping me on the road

Bar's Leaks 1100 Head Gasket Sealant

What a great product! I had bubbles in the radiator and white smoke from the tailpipe. The company that rebuilt my engine had gone bankrupt, so I had no recourse with them. I found your product online and decided to take a chance. It worked!  No more bubbles or white smoke. Thank you for keeping me on the road!

 by Justin R.
Still sealed after 4-6 months!

Not long ago, I was experiencing all the symptoms of a standard (although not severe, but more than “light”) leaking head gasket while leaving my hometown, headed to Memphis for a day trip. As much as I didn’t want to cancel the day trip, nor did I care to harm my motor, I decided to stop and grab a bottle of Head Gasket Sealant (1100). Followed instructions to the T, and not only did my large 5.4L V8 engine make it to Memphis with no issues, but it’s still operating as if nothing happened, and that’s been almost 4-6 months ago! 

Thanks Bar’s Leaks!

 by David G.
Would buy again

This is my review for Bar's Leaks Head Gasket Sealant (1100).

It has worked great at sealing the head gasket leak in my 2003 Dodge ram 1500 XLT 5.7 Hemi truck. Would buy again for any issues. 

 by Paul T.
Followed instructions to a T, worked great

My daughter’s 2012 Chevy Equinox started overheating and it was found to have a head gasket leak. We used your Head Gasket Repair #1100 and it worked great. She drove the car for 6 more months before trading it in on a new Equinox. I have been using Bar's Leaks products for 50 years and am a very happy customer.

 by Daniel B.
Cured bad head gasket

Used your Head Gasket Sealant (1100). 

I was experiencing a blown head gasket. The product worked as expected. Engine cleared up.

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