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What is Steel Seal?

Steel Seal is a unique mixture of chemical compounds that have been specially blended to react under sufficient heat and pressure to create a hardened seal in the damaged area of a head gasket or block.

However there are lots of products claiming the same thing.

While there are other products that claim to repair a blown head gasket in a similar way to Steel Seal and these products are predominately comprised of little more than Sodium Silicate and dye.

Unfortunately, while using Sodium Silicate will initially seem to fix the issue, Sodium Silicate is also commonly known as ‘Liquid Glass’ or ‘Water Glass’. The reason for this is that Sodium Silicate once heated and cooled down will harden to a glass like substance. This substance cannot possibly stand up to the heat and pressure within the engine and this ‘seal’ will eventually break and the problem of the blown head gasket will return.

Steel Seal Head Gasket Repair - Pouring
'K Seal used to be regarded as the best 'Fix' but Steel Seal is even better...'
BMW Magazine

Why Steel Seal?

99% Success rate

No one is perfect and no head gasket repair product can (honestly) boast a higher success rate than Steel Seal. A truly viable alternative to a mechanical repair

Money Back Guarantee

We are so confident in Steel Seal and its ability to repair a blown head gasket we offer a 30 day money back and replacement bottle lifetime guarantee.

Award Winning Product

Steel Seal has won awards for Best Product and Best Supplier from prestigious automotive retailers and as the formula improves will continue to win many more in the future.

Trusted since 1999

Since its creation, Steel Seal has helped 100,000’s of people to get back on the road, saving on repair bills and making Steel Seal a trusted option against a mechanical head gasket repair

No Tools required

Steel Seal’s simple pour in formula means that anyone can carry out the treatment, without the need for any complicated procedures or expensive specialist tools.

Thermochemical Formulation

Steel Seal's unique mixture of chemicals have been specially blended to react under heat and pressure to create a hardened seal, with no clogging due to fibrous particles or fillers.

We always insist on a mechanical repair

Yes you read that right!! Our goal first and foremost is getting you back on the road and the best way to ensure that happens is to get the head gasket replaced by a trained professional. 

Unfortunately, not everyone has the money to have the head gasket replaced and in some instances the vehicle isn’t even worth as much as the $1000 repair bill.

Its in these circumstances that Steel Seal is the best viable alternative.

Did you know? Steel Seal will repair both steel and aluminium head gaskets.

Blown Head Gasket symptoms

Always have a blown Head Gasket confirmed by a professional but there are symptoms you can look out for.

If you start your vehicle, especially on a cold day and see white smoke from the tailpipe then you are likely just seeing condensation, or steam. If this disappears once the vehicle has warmed up, then this is almost certainly the cause and it is perfectly normal and nothing to worry about. If after the vehicle has warmed up, and particularly under acceleration the smoke continues then it is time for further investigation as there is likely a more serious issue and could even be a symptom of a blown head gasket.


Many modern cars, have a oil cooler installed, which is cooled by coolant. A crack can occur inside the oil heat exchanger and this can lead to oil and coolant to mix. While there is a chance the issue is a leak in the oil exchange, a blown head gasket is the more common issue with oil in the coolant. If an engine overheats and stays heated for prolonged periods of time without cooling, the head gasket can crack which in turn causes oil to leak into the coolant system. READ MORE
Coolant as its name suggests keeps the internal system cool by moving from the engine to the radiator and back, over and over again ensuring your vehicle doesn’t overheat. If there is and loss of coolant the temperature of the engine will begin to rise and this is where the problems begin. A loss of coolant could be a cracked hose, a hole in the radiator or an issue with your water pump. READ MORE 
One of the most obvious signs will be the temperature gauge on your dashboard rising into the red or significantly above the normal range, or the displaying of a warning light. This can be sign of a blown head gasket. READ MORE
The cooling system on your vehicle Is a sealed system of pipes and hoses designed to pump coolant/antifreeze around the engine. This allows for a constant flow to reach components including the head gasket, engine block and cylinder heads this allows the engine to continue operating at the correct temperature. When air is allowed to enter the system blockages and bubbling is caused which can then cause overheating and further damage. READ MORE
One of the most common symptoms for a head gasket failure is a build-up of a milky sludge found on the underside of the oil filler cap or along the dipstick, commonly referred to as “mayonnaise”. READ MORE

When is a repair, not a repair?

Another reason Steel Seal maintains its high success rate is that we do not give up on the repair if it has not been 100% effective. If you have used Steel Seal and you still have symptoms, but the symptoms have improved you have what we refer it as a ‘Partial Fix’.

A partial fix is when the blown head gasket was particularly severe and another treatment of Steel Seal will repair the issue. We offer a free replacement bottle to complete the repair of your vehicle.

'A cheap fix does the job, to the amazement of all'
Nick Trott
Editor of Mitsubishi EVO Magazine
Steel Seal Head Gasket Repair - Radiator

How to use Steel Seal

1. Pour in Steel Seal

Make sure the engine is cold and the coolant in the cooling system is clean. Remove the radiator cap and pour the recommended amount of Steel Seal® directly into the radiator. Screw the cap back on. Tip: In vehicles without a radiator cap, Steel Seal® can be filled in via the expansion/surge tank*.

2. Run Vehicle in Idle or drive

If vehicle is roadworthy: Start engine and drive at freeway speeds for 5 to 10 miles, maintaining between 3,000 - 4,000 RPM, then shut off engine.
If vehicle is not roadworthy: Turn heater and fan to maximum. Start engine, run to operating temperature and then run on high idle (1,000 - 1,500 RPM) for 30 minutes. Turn off vehicle and allow to cool completely.
Warning: Monitor the temperature throughout the application (see engine temp gauge on dash) and if at any point it threatens to overheat, shut it down immediately!

3. Drive Away

If necessary, top up with fresh coolant up to the specified mark on the coolant reservoir. Simply leave Steel Seal® in the cooling system and continue driving your vehicle as usual!

Did you know? Steel Seal has been used to repair lawnmowers, motorbikes, cars, vans, trucks, trains and even once used on a plane!!

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