Top 7: The Best Head Gasket Sealer Reviews


If you are looking for a solution to your car engine’s head gasket problems, you are in the right place. Over time, head gaskets get weaker. This is because of normal wear and tear. In the end, you might have a blown head gasket. Remember that a mixture of lubricant fluid and coolant can be harmful to the engine.

Replacing the head gasket completely is the best option. However, it is costly as it can cost several thousand dollars. Therefore, you need a cheap option if you have a limited budget.

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In such a case, you will probably require the best head gasket sealer to assist you to solve the issue.

The best sealer is one that offers a quick but permanent fix. Fortunately, you can easily and quickly fix the leaking gaskets using quality sealers. As soon as the sealer is applied, it starts to fill any crevices or cracks.

Old engines are prone to leaky gaskets. If you value your vehicle, then you should be looking for the products that work effectively. So, what is the best head gasket sealer?

How To Check For A Blown Head Gasket 

Top 7 Picks of The Best Head Gaskets Sealers

1. ATP AT-205 Re-Seal Stops Leaks – Best Head Gasket Sealer

The ATP AT-205 Re-Seal Stops Leaks is an effective, fast, and safe stop-leak designed for all gaskets and rubber seals. This exclusive formulation fixes dried and worn out seals. Moreover, it is not harmful to the internal components and bearings.

It is effective at stopping leaks in:

  • Engines – diesel and gasoline
  • Power steering – manual and automatic
  • Differential – limited slip, locker, and conventional
  • Hydraulic systems – Jacks, industrial equipment, plows

It is made of AT-205, which is a plasticizer. This chemical has been used widely in rubber manufacturing to provide flexibility and hardness. As gaskets or seals get older, they dry out, wear and harden. Fortunately, treating them with this solution, will restore it’s sealing and flexibility properties and even rejuvenate it.

However, this sealer should not be used for repairing brakes (this is mentioned on the product label). It is compatible with synthetic and conventional oils, gear oil, ATF, hydraulic oil, and power steering fluids. Also, it does is not filled with petroleum distillates. Thus, it will not break down or over-swell seals.

One bottle of this sealer will fix a 6 quartz capacity. You can adjust your usage depending on the capacity. It can work on jacks, industrial equipment, and plows. It is proven to work efficiently and quickly.

In fact, engine seals need only five hours of running time, thereby saving you both money and time from costly repairs. This will not result in a seal becoming gummy or even breaking down, unlike most cheap head gasket sealers. You can use this solution to treat new seals such as o rings to ensure you have a high-quality leak free rebuild.

2. Bar’s Leak HG-1 HEAD SEAL Blown Head Gasket Repair – Best Head Gasket Sealer Runner Up

The Bar’s Leak HG-1 HEAD SEAL Blown Head Gasket Repair is meant to handle the toughest leaks. As you can see, it is my best candidate for the best head gasket sealer. It works by forming a seal that is stronger as compared to the engine’s original head gasket.

The fact that it is anti-freeze compatible means that there flushing or draining is not necessary. The estimated time it can take you is about 60 minutes and can be used for any particular engine.

A single bottle can treat up to three gallons of any 4 cylinder engine. This head gasket contains:

  • A broad range of non-clogging sealing additives in different sizes
  • Anti-freeze that is compatible with sodium silicate
  • Carbon fiber that acts as a rebar to create a permanent seal that works even on large leaks.
  • Xtreme Cool product that decreases water temperature and prevents overheating

Unlike BlueDevil Head Gasket Sealer, it offers permanent leak sealing solution, thus, saving you thousands of dollars that will have been spent in head gasket repairs.

3. BlueDevil Head Gasket Sealer

The BlueDevil Head Gasket Sealer will seal and repair leaks in cracked or warped heads, blown head gaskets, freeze plugs, and heater cores. It does not contain particulates or solid matter. Thus, it cannot harm or clog your engine. It easily bonds to metal, cast, aluminum, plastic, or alloy, and it is easy and safe to use.

This sealer is compatible with both diesel and gasoline engines. You should start by flushing out the cooling system and running your vehicle for at least 15 minutes. Add the sealant and disconnect the thermostat.

The reason you are advised to disconnect the thermostat is to ensure the solution gets to every part of the engine. With the thermostat on, it can easily divert the sealant. The following are benefits of using BlueDevil Head Gasket Sealer:

  • No flat spots while driving
  • No mayonnaise in the oil filter
  • Spark plugs appear to be clean

You should note that BlueDevil gasket sealer does not offer a permanent fix. In fact, it will work for about two years but will save you a lot of money on costly repairs. The success level of this product is much higher than most head gasket sealers currently on the market.

4. Bar’s Leaks 1111 Head Gasket Fix

The Bar’s Leaks 1111 Head Gasket Fix is an easy solution to help you stop head gasket fluid leaks. You do not need to drain the cooling system. This formulation contains various gasket sealing particles and antifreeze that is compatible with sodium silicate liquid. It works by penetrating cracks and gaps and hardens permanently to stop the leaks.

It seals due to extreme heat inside engine’s combustion chamber, which acts as a catalyst to harden the material. In fact, this makes it even much stronger as compared to the head gasket itself. This sealer can be used on both diesel and gasoline engines that are water cooled.

This heavy-duty formula works both on cast iron and aluminum heads and blocks. With this sealer, you can seal all other parts of your engine cooling system much better than using traditional stop leak products. For instance, you can use it to repair cylinder heads, gaskets, freeze plugs, cracked blocks, and intake gaskets.

If your vehicle’s cooling system is partially clogged or dirt, ensure you flush it first before using this sealer. Before using it, allow your vehicle’s engine to cool. This is necessary so that you can remove the radiator cap safely. Then, shake well and pour it directly into the radiator.

Fill the radiator to the proper level and close the radiator with the cap. You can then start the engine and give it about 20 minutes in idle mode. The Bar’s Leaks 1111 Head Gasket Fix will provide continues protection to your engine.

5. K-Seal ST5501 Multi Purpose One Step Permanent Coolant Leak Repair

The K-Seal ST5501 Multi Purpose One Step Permanent Coolant Leak Repair offers a permanent repair to the head gasket damage. The sealer has been scientifically engineered through a combination of microfiber particles and copper.

With this solution, you do not need to flush out the engine (engine flushing is a time-consuming activity). It is supposed to repair holes and cracks up to a diameter of 0.063mm. Thus, there is no chance of blocking other openings or tubes in the engine.

Unlike other sealers on the market, K-seal works with any anti-freeze. It is estimated to save you more than ten labor-intensive hours of disassembling your engine as it goes through the crannies and nooks in about 2 minutes.

Other than repairing bad or warped head gaskets, it can also be used to repair water pump casing, heater cores, freeze plugs, cylinder heads, and engine blocks. Thus, with the K-seal, you can skip going to your mechanic and use it instead.

Professional technicians and mechanics trust it. It is ideal for use in water-cooled engines including motorbikes, heavy machinery, commercial vehicles, and cars. Another important thing to know about K-seal is that it meets ASTM standards.

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6. Steel Seal Blown Head Gasket Fix Repair Sealer

The Steel Seal Blown Head Gasket Fix Repair Sealer is the perfect solution for blown head gasket, cracked engine blocks, and warped heads as it offers a permanent solution. It is meant to help you carry out simple DIY repairs and other mechanical repairs.

The good thing about this sealer is that you can use it on different types of engines and vehicles, which have a cooling water system. It does not matter whether your vehicle uses diesel or petrol, this sealer works quite well.

This sealer can also be used for repairing vans, bikes, lorries, tractors, and lorries. After sealing the leak using Steel Seal Blown Head Gasket Fix Repair Sealer, you do not anticipate any further leaks as it makes a permanent seal, which can withstand high temperature and high pressure.

Just like CRC Permanent Head Gasket & Block Repair, it works well when the engine system is flushed out first. This sealer has 99.6% success rate. A single bottle is sufficient for an engine with a capacity of two liters, and three bottles for an engine with a capacity of four liters.

7. CRC 401232 Permanent Head Gasket & Block Repair with Nanotechnology

The CRC 401232 Permanent Head Gasket & Block Repair is a top head gasket dealer you will find on the market only if you have knowledge and time to do some extra work. After installation, you will discover that it works longer and better as compared to the just pour and go solutions.

In fact, it is not like Bar’s or BlueDevil which you just pour, and you are done. Rather, it requires extra care and flushing out the system. You need radiator anti-rust, flush, a pan, anti-freeze, and hand tools. Start by draining the anti-freeze and then flushing the cooling system.

Ensure the system is flushed completely. If you cannot do this, it is advisable to stick with simple solutions. It is likely to take up six hours. It is an excellent solution than purchasing expensive head gasket replacements.

I prefer flushing the radiator and then applying this gasket sealer. It offers a better way of fixing the head gasket leak as compared to the easy pour sealers. The nanotechnology ensures that it gives a long duration but with a lot of upfront work.

This gasket sealer is ideal and recommended for trucks, buses, and other automobiles. It just weighs 2.5 lbs and contains 32 fl oz. It can be used for heater cores, engine blocks, radiators, cylinder heads, freeze plugs, and cooling systems.

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How Long Does Head Gasket Sealer Last?

First, you may ask yourself; does the does head gasket sealer work? If you have had head gasket problems and visited a mechanic shop, you may have noticed them adding a gasket sealer to the coolant. You should read several reviews and probably purchase one and give it a try. Although they are different, they work nearly in the same way?

Depending on the type of head gasket sealer you purchase, the longevity of the sealer varies from one make to another. This is mainly because there are no two products that are made the same.

Some gasket sealers such as Bar’s Leak HG-1 HEAD SEAL Blown Head Gasket Repair provide a permanent solution, while others such as BlueDevil Head Gasket Sealer fix the problem for about two years.

The following symptoms can help you know when the head gasket has failed and there is a need to purchase a sealer:

  • White smoke is emanating from exhaust – If you notice white smoke after 15 minutes of starting the engine early in the morning, it is a sign of gasket failure or damage.
  • This is because the coolant is making its way into the engine combustion chamber.
  • Flat spots while driving – this is a sign of water or oil getting into engine’s combustion chamber.
  • Mayonnaise inside oil filter cap – this is a sign of head gasket failure. Still, it can also be a sign of little use of the vehicle.

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Did you enjoy reading the provided list of head gasket sealer reviews? After analyzing several products, the above 7 picks proved to be great and useful. Moreover, they are quite affordable and can be purchased online.

The best head gasket sealer can save you money, time, and offer you peace of mind. This is because it engine overheat will keep fluids out of your vehicle’s engine after detecting leaks, white smoke emanating from the exhaust pipe, or.

The only time to take your car to a professional technician or mechanic is when there are serious underlying problems after attempting easy solutions.

If you have any suggestion, kindly share it in the comment section, and I will be glad to consider it. Also, if you have queries, I will be glad to answer them. Feel free to share this list with your friends and colleagues.

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