The Best Head Gasket Sealers in Australia

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A blown head gasket can be a frustrating problem in both diesel and gasoline engines. Head gasket sealants are an easy option that can be effective against less severe damage. They work well as pour and go solutions for head gaskets that have minor leaks. Most head gasket sealers are placed into the radiators of engines and move around the cooling systems of the vehicles when the engines are turned on and warmed up.

To help you find the best solution for your vehicle, we’ve reviewed and compared some of the most popular products on the market. Here are our picks for the best head gasket sealers:

Nulon Permanent Head Gasket Repair

Nulon Permanent Head Gasket Repair is a head gasket sealer that provides a permanent fix for blown head gaskets. Nulon is compatible with antifreeze and is formulated to create a permanent seal in head gaskets that have minor leaks.

Nulon is also safe to use in a plastic radiator, in a heater core, or even a power steering system. This dependable professional grade head gasket sealer can also be used in both gasoline and diesel engines, fulfilling the needs of a wide range of drivers.

K-Seal K5501 Coolant Leak Repair

K-Seal K5501 Coolant Leak Repair is a multi-purpose fluid that provides a pour and go solution for anti freeze leaks, whether from radiators or through head gaskets.

While not specifically designed as a head gasket sealer, K-Seal K5501 effectively seals minor head gasket leaks.

To use K-Seal, drivers simply need to shake the canister of fluid, pour the solution into the radiators of their vehicles, and allow the fluid to seal the minor cracks and leaks that are in the engines of their vehicles. K-Seal K5501 should only be placed in a radiator when the vehicle has cooled off.

Rislone Head Gasket Fix

Rislone Head Gasket Fix is a head gasket sealer that quickly produces a steel seal that stops leaks in a head gasket. Rislone is easy to use, mixes with a vehicle’s anti freeze, and does not require a fluid flush.

To harden quickly after being mixed with a vehicle’s coolant, Rislone uses the combustion heat of the vehicle. The heat allows the formula of Rislone to harden harder than the vehicle’s head gasket itself.

This head gasket sealer will work on your vehicle if its head gasket isn’t too damaged and the vehicle can sit at idle for at least 20 minutes without overheating.

Bar’s Leak HG-1 Head Gasket Repair

Bar’s Leak HG-1 Head Gasket Repair is a permanent head gasket sealer that drivers can mix in with the coolant of their vehicles. Bar’s helps drivers save money on expensive repairs by providing a simple and quick solution for blown head gaskets.

This head gasket sealer permanently seals leaks by filling gaps and cracks with its specially-formulated compound. Once the liquid has entered and filled the gaps, it quickly hardens to create a solid seal.

Bar’s Leak HG-1 is safe for use with most components, including freeze plugs.

BlueDevil Head Gasket Sealer

Prevent your vehicle’s freeze plugs from overheating with BlueDevil Head Gasket Sealer. BlueDevil Head Gasket Sealer is a permanent sealing solution for a variety of cracks and leaks.

BlueDevil works for a multitude of problems, including situations where a vehicle’s engine block is warped or its cylinder head is cracked.

Designed to seal damaged head gaskets, BlueDevil Head Gasket Sealer can solve and eliminate many of the problems that are caused by leaking head gaskets, such as overheating and coolant loss. If the damage in your vehicle isn’t too severe, then BlueDevil can make its repair.

How to tell if you have a blown head gasket

There are several signs that car owners should look out for when they are trying to determine if the head gaskets of their vehicles are blown. Many blown head gasket warning signs are obvious, while some are less-noticeable.

One of the most obvious signs that an engine’s head gasket is blown is a plume of white smoke being emitted from the exhaust pipe of the vehicle. This white smoke is combusted coolant that leaked into the vehicle’s cylinder heads.

A routine loss of coolant is another warning sign that your vehicle’s head gasket may be blown. However, you will need to check to see whether or not the coolant is leaking. Leaking coolant is a sign that a part on your vehicle is either loose, cracked, or ruptured. In contrast, if you cannot identify a coolant leak on your vehicle but notice that the vehicle is continually losing coolant, then your vehicle may have a blown head gasket.

A vehicle will repeatedly overheat when its head gasket is blown. The head gasket of a vehicle allows coolant to flow smoothly throughout its cooling system. However, this flow is disrupted when the vehicle’s head gasket is blown, preventing proper cooling.

One of the less noticeable signs, but a sure sign that your vehicle’s head gasket is blown, is milk-coloured oil. If you check the oil of your vehicle and notice that it has a white complexion then your vehicle’s head gasket is certainly blown.

The milky colour that you are seeing is the mixture of both oil and coolant with one another, which only occurs when a blown head gasket allows coolant to flow with oil. Check the colour of your vehicle’s oil through the use of its dipstick if you suspect that the vehicle has a blown head gasket.

Depending on the amount of time that you have owned your vehicle, you may notice a significant decrease in performance when its head gasket is blown. The blown head gasket will prevent the vehicle from having enough pressure in its cylinders. In turn, the decreased pressure within the engine block will prevent the vehicle from having its usual power.

RELATED: The Best Engine Oils

The head gasket repair process

In order for a mechanic to repair a blown head gasket, for both diesel and gasoline engines, they have to remove the cylinder head of the vehicle’s engine.

The head gasket of an engine is located between its cylinder head and its engine block. If your vehicle has a V-shaped engine design, then the technician will first need to identify which of the head gaskets underneath the engine’s two different cylinder heads is blown before beginning the repair.

Aside from all of the parts, both big and small, that will need to be removed from the engine of your vehicle to access its head gasket, the technician will also need to flush your vehicle’s cooling system and its oil, among a variety of other tasks.

Head Gasket FAQ

How much does it cost to replace a head gasket?

The average cost to replace the head gasket of a vehicle ranges between $1,000 and $2,000. The price range is so wide due to the varying engine designs that are used on vehicles. The head gasket components themselves do not usually cost very much money, but there is a lot of labour that is involved during a head gasket repair service.

Can you still drive a car with a blown head gasket?

Blown head gaskets can be a nuisance and should not be driven with once identified. While a vehicle can be driven for a limited time with a blown head gasket, depending on the severity of the issue, the vehicle will eventually need to be repaired. Head gaskets that have minor leaks can be driven minimally, but the leak will need to be sealed with a dependable sealant, or the head gasket will need to be replaced to prevent further damage. Engines that have more severe damages, such as cracked heads, as a result of their head gaskets blowing, may not even start or run for very long.

Is it worth fixing a head gasket?

Fixing a head gasket can be worth its price based on the age of your vehicle and the damage that has been done. Engine blocks, water pumps, heater cores, and many other components can be damaged because of blown head gaskets. Therefore, a mechanic will need to closely inspect your vehicle to see what it needs. In many cases, a head gasket repair, a radiator flush, and a few other services are all that are needed to repair the vehicle. However, there are also many blown head gasket cases where overheating led to irreparable damages to engine blocks, cylinder heads, and more.

Do head gasket sealants really work?

Head gasket sealants do work for vehicles, but the effectiveness of the sealant depends on the severity of the damage that it has to seal. Head gasket sealers are great for head gaskets that have minor leaks and work as pour and go solutions for these leaks. However, in situations where head gasket block repairs have to be done, for example, these sealants will not remedy the issues very well.
To use a head gasket sealer in your vehicle’s engine, you first need to identify which sealant you want to use in the engine. Most head gasket sealers are placed into the radiators of engines and move around the cooling systems of the vehicles when the engines are turned on and warmed up. While the sealant will certainly work for the engine of your vehicle, it will most likely work as a temporary solution, depending on which head gasket sealer you choose.