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Your car’s head gasket probably never comes to mind until something goes wrong. Since this is the piece that is between your cylinder heads and the cylinder block, it’s a fairly vital part that doesn’t need too much attention until there is a crack, which can cause some leaking.

The head gasket is there to maintain compression while also preventing leakage of coolant and oil into the cylinders. If there’s a leak or issue, it should be dealt with soon so that no further problems occur. A blown head gasket is far more expensive to deal with, so a band-aid solution is to use a head gasket sealer.

Why Do You Need a Head Gasket Sealer?

There are a number of symptoms of a head gasket that needs repair. The first thing you’ll notice is that the engine starts to overheat, you may see white smoke from the exhaust, and there may be some engine misfires. Furthermore, if the oil looks milky, if there are bubbles in the cooling system, or if the coolant is missing without a visible leak, you may have a faulty head gasket.

If the car overheats within 15 minutes, it’s clear that there’s a very significant issue with gasket and it will need a real replacement, rather than a sealant. Otherwise, a sealant could work.

Does Head Gasket Sealer Work?

Many car owners on a budget swear by head gasket sealers, especially in regards to vehicles using the 2.5-liter flat-four cylinder engine by Subaru.

Head gasket repairs can be very costly, so sealant is worth trying. They can definitely help prolong the life of your car. After using a head gasket sealer, be sure to check back on your car after a few days to ensure there are no more leaks. You can be sure the sealant worked by noticing that the overheating issues have stopped popping up.

How does a Head Gasket Sealer Work?

A head gasket sealer works when you pour it into the radiator. You run the car for about 15 to 30 minutes, with the heater and fan on high. Then the special chemicals in the sealant work via heat. They will seek out and fit in cracks and gaps in the head gasket. Then they’ll harden to complete the repair.

These sealants might not be the most permanent and could wear down over time. A real fix is to replace the head gasket, but this is costly. A head gasket sealer is a good temporary fix.

The amount of sealant you use depends on how big your engine is. Vehicles with eight or 10 cylinders will likely need more sealant than those with four or six-cylinder.

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Steel Seal Blown Head Gasket Fix Repair Sealer

Many buyers are skeptical that a chemical solution can be found for their mechanical issues, but the Steel Seal products all come with a money-back guarantee to help provide peace of mind to those looking to fix their head gasket issues. This product is ideal for six-cylinder engines and will help users prevent excess antifreeze consumption and engine overheating. Users note that the instructions have to be followed very carefully in order for the product to work.

K-Seal HD Multi Purpose Permanent Coolant Leak Repair

K-Seal suggests that its product can fix leaks in just three minutes, which seems very optimistic. Customers seem to back it up, saying the product works as advertised. It also blends with different types of antifreeze, which isn’t common in the world of sealants. This item in-particular boasts compatibility in HD applications, like RVs tractors, trailers and large capacity engines.

ATP AT-205 Re-Seal

ATP is a trusted brand for many at-home and professional mechanics. This AT-205 Re-Seal can be used for much more than just head gaskets, but many have had success using it to prevent overheating issues. ATP describes the AT-205 as a plasticizer, which is a type of chemical used in rubber manufacturing to set hardness and flexibility. There are plenty of reviews that boast the success rate of the re-seal, so it must be trustworthy.

Bar's Leak HG-1 HEAD SEAL Blown Head Gasket Repair

This is another popular item mainly due to its ability to be used in so many applications. Customers boast success rates with engines including turbochargers or several cylinders. It’s extremely versatile, and is antifreeze compatible, without needing a radiator flush. That’s a huge time saver, and the manufacturer believes that a fix can be completed in as little as 45 minutes. Some customers have said there can be issues with plugging heater cores as well, but many give the product a rave review.

BlueDevil Head Gasket Sealer

This is a popular item due as seen by the many Amazon reviews. It features a three and a half star rating, which means it has clearly worked for a number of customers. Many commend the BlueDevil solution because it’s a very easy product to use even for those who haven’t performed many car repairs or maintenance before. It has a high-temperature adhesive as well as sodium silicate and doesn’t feature any engine harming solids or particulates. One bottle of it will seemingly work for six-cylinder engines, but you may need more product for bigger engines.

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