What is the best head gasket sealer additive?

Status
Not open for further replies.
Joined
Jul 20, 2007
Messages
3,742
Location
Northern California, USA
What is the best head gasket sealer additive? I have seen some that are $40 a bottle, and some that were $3. I know the best thing to do is to replace the head gasket. I am not sure if one of my head gaskets is leaking. I think there might be a small one-way leak that only allows combustion gasses into the coolant, but doesn't allow coolant to pass into the cylinder. If the additive fixes my problem, I will know the gasket needs to be replaced. If it doesn't then it probably doesn't have a bad head gasket and I will have to find another solution.

What are the negatives of using a head gasket sealer? Can some of the metallic additives react with the other metals (aluminum and iron) in the engine to cause some type of galvanic corrosion?
 
Last edited:
One problem with at least some head gasket sealer products is that they can require a lot of time and work to use according to the directions on the label. For some engines, it's about the same amount of work to replace a head gasket and a lot less turn-around time. Obviously, there are engines where it's a big deal to replace a head gasket but it isn't always as big a deal as using a sealer product.

Edit:
Also, if the sealer must be installed with water only in the cooling system (no anti-freeze) that could add an additional complication in cold weather.
 
Last edited:
Why would you bother with this stuff if you are not sure whether you have an actual leak or not?

At least get a test kit that can detect combustion gases in the coolant at any auto parts store, BEFORE you use that junk.

The other issue is once you use this stuff it can permemently hinder heat transfer after you decide to fix the actual problem.
 
Originally Posted By: Loobed

What is the best head gasket sealer additive? I have seen some that are $40 a bottle, and some that were $3. I know the best thing to do is to replace the head gasket. I am not sure if one of my head gaskets is leaking. I think there might be a small one-way leak that only allows combustion gasses into the coolant, but doesn't allow coolant to pass into the cylinder. If the additive fixes my problem, I will know the gasket needs to be replaced. If it doesn't then it probably doesn't have a bad head gasket and I will have to find another solution.

What are the negatives of using a head gasket sealer? Can some of the metallic additives react with the other metals (aluminum and iron) in the engine to cause some type of galvanic corrosion?



Big negative is that most of these sealers once wet, and then exposed to air will clog up where ever they are, so if you EVER just drain the radiator / cooling system, after you have added some of these sealers, they react with being exposed to air, and clog up the cooling system. And a lack of cooling will result in serious over-heating on hot days. In addition to lack of cooling the engine, if the cooling system is EVER just drained the sealant in the heater core exposed to air will clog the heater core, and reduce the amount of heat available to the cabin on cold days, resulting in cold cabin, and also less ability to de-ice the windshield and windows.

Adding water to the system and letting the cooling fluid drain out WITHOUT EVER EXPOSING THE INSIDE OF THE COOLING SYSTEM TO AIR WITH THE ADDITIVE IN IT, SO AS TO FLUSH THE ADDITIVE OUT BEFORE DRAINING THE COOLING SYSTEM, MAY PREVENT THE ADDITIVE FROM CLOGGING THE COOLING SYSTEM, AND HEATER CORE. But any additive left in the system will clog up the cooling system.
 
Originally Posted By: antiqueshell
Why would you bother with this stuff if you are not sure whether you have an actual leak or not?

At least get a test kit that can detect combustion gases in the coolant at any auto parts store, BEFORE you use that junk.

The other issue is once you use this stuff it can permemently hinder heat transfer after you decide to fix the actual problem.



This is my post about a cooling system leak from July

http://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=2744794
 
Last edited:
Have you tried this yet?

http://barsproducts.com/catalog/view/6-radiator-stop-leak-tablets-hdc

I recently put some of the GM version (PN 3634621) in my daughter's Avalanche 5.3. You have to break up the tablets and put them in the upper radiator hose. Don't put it in the radiator unless you have a radiator cap. You can't put it in the reservoir either.

It's a mixture of ginger root and walnut shells. It's supposed to swell when it finds the air and stop the leak.
 
I used bars permanent head gasket stop leak stuff on a freinds moms car. She couldnt afford to fix it so we tried it amd it worked and has worked for 8 months. Dont let people give you [censored] about it. This stuff has its place. If you need the car and cannot afford to fix it properly or the car isnt worth the job this stuff will usually work.
 
Do not put anything in the cooling system. Every vehicle I've seen a stop leak put in the heater cores lifespan gets a whole lot shorter,unless you aren't planning on keeping it.
I know from experience that you can add gasket swellers to oil and the only issue will be needing them on a consistent basis,or the leak returns. The cooling system however is hit and miss. Fix the gasket,or in time you'll be fixing the gasket and replacing a heater core as well.
 
Originally Posted By: Dakota1820
I used bars permanent head gasket stop leak stuff on a freinds moms car. She couldnt afford to fix it so we tried it amd it worked and has worked for 8 months. Dont let people give you [censored] about it. This stuff has its place. If you need the car and cannot afford to fix it properly or the car isnt worth the job this stuff will usually work.



Bar's sells 4 different kinds of head gasket stop leak (and several more types of radiator stop leak). Do you know which one it was?

I am leaning more towards the copper stuff.

http://www.barsproducts.com/catalog/brand/all/component/gaskets
 
Originally Posted By: Loobed
Originally Posted By: Dakota1820
I used bars permanent head gasket stop leak stuff on a freinds moms car. She couldnt afford to fix it so we tried it amd it worked and has worked for 8 months. Dont let people give you [censored] about it. This stuff has its place. If you need the car and cannot afford to fix it properly or the car isnt worth the job this stuff will usually work.



Bar's sells 4 different kinds of head gasket stop leak (and several more types of radiator stop leak). Do you know which one it was?

I am leaning more towards the copper stuff.

http://www.barsproducts.com/catalog/brand/all/component/gaskets



If you're leaning towards the liquid copper stuff you're also leaning towards doing a UOA first. You need to know that there isn't any coolant getting into the oil before you use that stuff. Liquid glass in the oil can cause...problems...as such.
 
Originally Posted By: INDYMAC
Have you tried this yet?

http://barsproducts.com/catalog/view/6-radiator-stop-leak-tablets-hdc

I recently put some of the GM version (PN 3634621) in my daughter's Avalanche 5.3. You have to break up the tablets and put them in the upper radiator hose. Don't put it in the radiator unless you have a radiator cap. You can't put it in the reservoir either.

It's a mixture of ginger root and walnut shells. It's supposed to swell when it finds the air and stop the leak.


I have seen some dealerships use it as a "last ditch effort" and heard that it worked in a decent amount of cases enough to make me consider it soon as a preventatitve.
 
Originally Posted By: Bgallagher
Originally Posted By: INDYMAC
Have you tried this yet?

http://barsproducts.com/catalog/view/6-radiator-stop-leak-tablets-hdc

I recently put some of the GM version (PN 3634621) in my daughter's Avalanche 5.3. You have to break up the tablets and put them in the upper radiator hose. Don't put it in the radiator unless you have a radiator cap. You can't put it in the reservoir either.

It's a mixture of ginger root and walnut shells. It's supposed to swell when it finds the air and stop the leak.


I have seen some dealerships use it as a "last ditch effort" and heard that it worked in a decent amount of cases enough to make me consider it soon as a preventatitve.


That stuff works great for small leaks in radiators, but NOT in head gaskets. Back in the late 1970s and early 1980s, we used that a lot in our teen age $500 hot rods.
 
Have you looked into the Subaru Cooling System Additive (Holts Rad Weld)? It looks a lot like Bars stuff. It is said that Subaru recommends this stuff to prevent the notorious head gasket problems.
 
Minor external leaks you can fix with cheap bars leak, anything else you need to replace the gasket. Think of where the pressure is, an external leak is going to always flow out and clog with stop leak. Anything involved with the combustion chamber and its high pressure isn't going to do that.
 
Last edited:
Originally Posted By: CarbonCrew
Have you looked into the Subaru Cooling System Additive (Holts Rad Weld)? It looks a lot like Bars stuff. It is said that Subaru recommends this stuff to prevent the notorious head gasket problems.


Thats funny.. known for their head gasket issues encouraging customers to use an additive instead of fix the real problem??!!! sketchy
 
I have worked with guys that got positive results from Blue Devil sealant, but I have not heard of anything else that works.

"Not recommended for Northstar engines" is written on every bottle. I hope you don't have a Northstar.
 
A combustion to coolant leak may be too powerful to let the stop leak work, way different than coolant-to-outside of engine that will only develop what your rad cap pressure is, if there's no coolant bypass.

If you use the Bars Leak permanent (taller silver bottle 33.00 at Napa) and if possible,use a lower psi cap to give this a chance to work.
If it's a very small leak,this might work.
If the leak is pressurizing the crankcase, check pressure the oil fill hole by blocking the PCV,it may be too small to tell.
Lot of 'If's' in this one.

http://www.barsproducts.com/catalog/view/14-head-gasket-fix-1111
 
Status
Not open for further replies.
Back
Top