Can you really fix a head leak with liquid head gasket sealer?

• Cracked Head Sealant
• Can You Repair A Broken Head
• Can You Seal A Cracked Head

Your mechanic is being slightly untimely in his diagnosis. You have a blown head gasket and or a warped cylinder head. This could be desperate on the time of disassemble. The two are no longer sturdy information, yet are much less intense priced whilst in comparison with changing a cracked head. I could say take it aside and function it directly edged for warpage and magnifluxed to verify. At Steel Seal we don’t just believe in selling chemicals or offering cheap temporary fixes, our aim is to get drivers back on the road, permanently. This is why if you have a blown head gasket and have followed the instructions above without success, we will provide a full refund under our guarantee. If a engine block develops a crack, JB Weld can be used to seal up the crack and prevent the crack from sucking in air or leaking coolant. JB Weld is a type of epoxy that seals and hardens to close cracks and holes. JB Weld is made up of a resin and a hardener.

Here’s the bad news: Most of the time head gasket sealers don’t work. Even it if does, it’s never a permanent fix. Whether it works on your engine depends on how the head gasket failed. If your head gasket leak appeared after your engine overheated, give it up, head gasket sealer is not going to work. However, if your car didn’t overheat AND the leak is between the combustion chamber and the cooling system, where you have white smoke coming from the tail pipe, you might have a chance for a temporary fix. Read on to find out how this stuff works and when it works.

What causes a head gasket leak?

Head gaskets can fail between the between the combustion chamber and the cooling jacket, between the cooling jacket and the oil passages or between a cooling or oil passage the exterior of the engine.

Leaking head gasket symptoms:

Head gasket failure between the cylinder and the cooling jacket

• Engine overheats quickly because very hot air/fuel/exhaust gasses are being pushed into the cooling system. Those hot gasses quickly overheat the coolant that’s why the engine overheats so quickly

• Coolant overflows out of the coolant reservoir. See above. Plus, all that extra gas/exhaust pushes the coolant out of the engine.

• Upper and lower radiator hoses become very hard when engine is running or detach from the engine completely. The gas/exhaust gasses raise pressure in the cooling system.

• White smoke comes from the tailpipe because coolant leaks into the combustion chamber, is burned and exists the exhaust as steam.

• Coolant reservoir empty because the coolant is being burned

Head gasket failure between the cooling jacket and oil passage

• Coolant in the oil that turns the oil into a chocolate milkshake color, OR you find oil in the coolant.

Head gasket failure between the cooling jacket and oil passage and the exterior

• An oil or coolant leak from the head gasket to the exterior will usually cause oil stains on your garage floor or driveway.

• Oil and coolant levels will be low even after your refil

• Coolant reservoir will be low or empty.

What causes the gasket to leak in the first place?

Sometimes it’s just a poor gasket design. But most often it’s because of owner neglect by not changing coolant according the manufacturer’s schedule. Coolant contains anti-corrosive additives and when they’re exhausted, corrosion build up and degrades the metal surfaces in the cylinder head and head gasket. When a head gasket fails due to coolant neglect, it usually shows up as coolant and oil mixing together to form a chocolate milk-like substance in the radiator.

How does head gasket sealer work?

Plugging head gasket sealers

A plugging type head gasket sealer contains wood pulp, pepper, ginger root, etc and works by filling the gap while the system is under pressure; like sticking a finger in the dike.

The plugging products are pretty much obsolete. They don’t work well in modern aluminum engines. They work sometimes to stop a cooling system leak in a radiator or heater core where the pressure is less than 15-psi. But they don’t work very well for head gasket leaks because the pressure can easily run up to 200-psi. Worse yet, they can plug the very small passages in your radiator or heater core.

Nano liquid glass style head gasket sealers

Bars Leaks HG1 or CRC’s KW FiberLock sealer are just two of the newer nano-technology sealers.
These work with a 1-2 punch. First, they contain a plugging sealant that forms a “finger in the dike” patch. Next, the temperature sensitive chemicals attach to the plug material and melt out of suspension to form a longer lasting. Most sealers of this type use sodium silicate, or liquid glass. The “glass” in Sodium silicate activates from high heat, the kind found around the steel ring at the top of the cylinder. The nano particles form a patch along the hottest areas of the head gasket and continue to build until the breach is sealed.

Sodium silicate sealers don’t work inside a radiator or heater core because there’s not enough heat to melt the glass out of suspension. This chemistry doesn’t work for head gasket leaks between a coolant and oil passage.

Which engines aren’t good candidates for head gasket sealer?

If you’ve overheated your engine and warped the head, you’re kidding yourself if you think either of these types of head gasket sealers will fix the problem. When a cylinder head warps, you wind up with a gap that expands and contracts during the normal heating and cooling cycles. No sealer is going to work in those cases.

Now let’s talk about the real candidates for head gasket sealer

1) First, your engine must hold coolant for at least 20 minutes without overheating. If it can’t do that, forget about head gasket sealer.

2) If the cylinder head isn’t warped due to overheating, but the head gasket has deteriorated due to poor design, pre-ignition or corrosion (not overheating) then you can give it a shot. In these cases, sealers often have an 80% success rate.

Do the more expensive head gasket sealers work better?

No. The all work with the same two technologies. The expensive ones use hype and guarantees to lure you in. If you like being scammed, played for a sucker or just plain victimized, go ahead and spend $100 and buy the expensive sealers.

Read the directions before buying a sealer

Here’s the thing about head gasket sealers; most of the sealers aren’t compatible with coolant. So you have to drain the entire (and I do mean the entire) cooling system and refill the engine and radiator with plain water before adding the sealer.

That means you have to flush the radiator, heater core, and block (pulling the threaded block plugs). Then you pour in the stuff with water and run the engine for the specified time. Then you have to drain the system again and leave it open to the air for 24-hours. Only after you’ve done that can you fill with coolant.

These sealers rarely work. They’re a lot of work for such a lousy payback. Worse yet, the leak must be small enough to allow you to run the engine long enough without leaking for the sealer to work. That’s a feat unto itself because once the engine reaches operating temperature and builds pressure it usually start leaking.

Gasket sealers can damage your radiator and heater core

Everyone online forum will tell you they plug up the radiator and heater core. Well—they can if you don’t follow the directions. Because these sealers contain a plugging agent, never add more than the label recommends. If you add too much, the plugging agents settle out of the liquid and clog the small fin tubes in the heater core and radiator. This is a case where more is NOT better.

© 2012 Rick Muscoplat

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Blowing a head gasket is one of those things that you can’t understand the trouble of until it happens to you. Sometimes there are warning signs, but often it just happens seemingly out of nowhere. That was what happened to us, driving in our second hand Ford to a festival in 2011, when all of a sudden a huge cloud of black smoke appeared over the car. Unfortunately, we didn’t have a head gasket sealer back then. But now we’re more careful and make sure to always carry one. These are our top five head gasket sealers.

Contents

• 1 Top 5 Best Head Gasket Sealer 2020 Reviews

Top 5 Best Head Gasket Sealer 2020 Reviews

1. Bar’s Leaks 1111 Head Gasket Fix 24oz

This head gasket sealer is a fast acting solution which will lock up any leaks in no time. It is a mix of sodium silicate and various particles that when exposed to air will harden and completely seal any small rupture. It’s not the cheapest one available, but it comes in a large bottle and is highly effective for small bursts. That said, it is not advisable for bigger ruptures. The idea is that it will seal small gaps and long cracks. If you have a bigger rupture, you may need another solution, or to get a full repair. Also, if your engine is complex or delicate, do not use this sealer. Its particles may mean it sticks where it shouldn’t, resulting in internal damage. Great for your jeep or family car, not good for vintage vehicles or supercars. When using it, be sure to follow instructions closely to make sure it works well.

Our Rating: (3.9 / 5)

2. Permatex 80062 High Tack Gasket Sealant 4oz.

If you don’t want to spend a lot of money on a head gasket sealer, but you still want peace of mind, this may be a solution for you. This sealer is very tacky and will seal most cracks and gaps, including some larger gaps that bigger brands cannot handle. It comes in a smaller amount than many other sealers, in 4, 9, and 16oz containers, which means you can just keep a small jar in your car’s emergency box. And even at that size, it’s still great value for money. Plus, if you’re not feeling confident about your ability to apply it and you want minimal wastage, it comes in aerosol cans. This makes it much easier to use. It is also a great option when you just want to hold a gasket together until it gets to the repair shop, as it dissolves easily with spirit-based solutions. This sealer is the most foolproof one on the market.

Our Rating: (4.5 / 5)

3. Bar’s Leaks HG-1 Head Seal Blown Head Gasket Repair 33.8oz.

If you want a highly versatile sealer, then this is one of the best on the market. This is again more expensive as a single purchase. But not only is it very economical for a Bar’s Leaks product, it’s also useful for more than a blown head gasket! You can use it for all sorts of cracks and leaks in your car, from oil, to windscreen wiper fluids, to dripping brakes. You don’t need to flush before using it, and it’s antifreeze compatible too. Choosing this option really covers all bases. Bar’s Leaks reports it as their strongest product, and it really lives up to the title. Because of its unique mix, don’t try and mix it with anything before applying, and don’t use it on an area you have already treated with another sealer.

Our Rating: (3.7 / 5)

4. Steel Seal Blown Head Gasket Fix Repair Sealer 16oz

This is the most expensive one on our list, but it’s included for good reason. Many head gasket sealers dry and seal very quickly. This is great when you have a simple 4 cylinder engine. But when you have a 6 or 8 cylinder engine, the extra folds and extra complexity get in the way. They could mean your sealer hardens before it gets very far, or doesn’t coat thoroughly. Steel Seal has a few specific ranges of head gasket sealers for different cylinder engines. They have been tested and found to make sure the sealer reaches deep inside your head gaskets, sealing cracks and problems even at the furthest cylinder. This is especially important as Steel Seal advertises itself as a permanent fix. And trust me when I say, Steel Seal 4 cylinder will not permanently fix a head gasket crack in an 8 cylinder engine.

Our Rating: (3.7 / 5)

5. Blue Devil Head Gasket Sealer 32oz

If you need a large container but you’re on a budget, this is a good choice. It’s our favourite economical head gasket sealer, as it acts fast and seals strongly, even in more complex engines. It’s also free of any particles, making it gentle for even older or more delicate engines. And it’s another one that is advertised as a permanent fix, which is a little misleading. Although it can permanently fix smaller cracks and gaps, for the average-sized head gasket burst it will just glue everything together a short while. But it’s a good, fast solution that will help keep your car running long enough to get it home, get together the money for more complicated repairs, and sort your paperwork.

Our Rating: (3.7 / 5)

What is a Head Gasket Sealer

Many people purchase a head gasket sealer under the mistaken impression that it will totally and completely fix a worn-out head gasket. This is false for two reasons. Firstly, many head gasket sealers are not made to last that long! They can last quite a long time for cracks and minor leaks, for sure. But many will not last more than a week for big cracks, if they cover them at all.

The second reason it’s false is that your head gasket blew for a reason. There is something wrong internally with your car which created too much pressure, or which wore down the head gasket to a point where it couldn’t stand normal pressure. You can patch the head gasket, but if you don’t fix the root of your problem, the seal might break, or another head gasket might burst.

A head gasket sealer is largely a temporary patch until you can get a proper repair done. Or it may permanently fix that one crack, but you will still need to have your car checked to diagnose the root of the problem. When you blow a head gasket, whatever you do, you will always need your car checking over!

How to Prevent Blowing A Head Gasket

Cracked Head Sealant

We found ourselves standing next to our car in a service station parking lot. The repair team had arrived and said the head gasket had blown. As we waited for a tow truck so we could get the car to a repair shop, where we could collect a hire car, we wondered what we could have done to prevent this. There is never a good time to blow your head gasket, but our situation really drove it home how difficult it can be. We had to wait for a tow truck, go almost all the way home, then move all our stuff into a hire car. We barely made it to the festival by sundown. Then there were all the costs. Towing, repairs… at least the hire car was complementary. And we were determined never to have that happen again. This is especially important as, as we have discussed, sometimes a head gasket can’t be fixed with sealant alone. To avoid blowing a head gasket:

1. Bear in mind all head gasket bursts are caused by overheating. Normally your car can cool itself, but in certain circumstances it may have difficulty doing so. This is usually due to age or damage.
2. Use the right coolant. All manufacturers specify which coolant to use. Using the wrong one can rust your engine from the inside out, leading to cooling jacket blockage.
3. If your car has any work done on its cooling system, ensure all parts are compatible and working well. Use a workshop that specializes in your make of car to avoid getting dodgy or false replacement parts.
4. Check over your cooling system regularly. Learn the signs of damage in the hoses, pump, and thermostat and keep an eye out for them. Replace anything that breaks.

Can You Repair A Broken Head

How to Use a Head Gasket Sealer

It is very important to bear in mind that using a head gasket sealer incorrectly won’t only fail to repair a rupture, but may further damage your vehicle. Make sure that your head gasket sealer of choice is safe for your vehicle. Check:

• The cylinder number recommended for this sealant.
• The particle content in this sealant.
• Whether this sealant is advised for small or large breaks.

Once you’re sure you have the right sealer for the job, check the instructions. Most advise pouring straight into the radiator cap, but some require a flush, and others are applied externally to visibly damaged head gaskets. Always follow manufacturer instructions. Within an hour your car may be fixed. However, as mentioned before, bear in mind that this will only be a temporary patch on large breaks, and that if there is internal damage, you may blow a head gasket again.

Our Top Pick

As for our favourite? It has to be Bar’s Leaks HG-1 Head Seal Blown Head Gasket Repair. It’s a highly versatile product, useful for most common vehicles, and not too expensive to buy and keep in your car. It fully seals most small cracks and will hold your big leaks together potentially for over a month whilst you get everything in order. If you have a more delicate car, an older car, or a supercar this may not be the sealer for you. But for most of us, this product is an essential car-care item to carry in our vehicle at all times.

Can You Seal A Cracked Head