Head gasket failure is a symptom, not the cause of overheating. The original source of cooling system failure, if still present, must be repaired before attempting to repair your head gasket.

**STEEL SEAL IS NOT COMPATIBLE WITH All ANTIFREEZE FORMULATIONS** Therefore, for best results, coolant should be temporarily drained and replaced with fresh water. Once repaired, drain Steel Seal from the cooling system and replace with 50/50 antifreeze.

Water in oil

If water is present, you must change the oil and filter before proceeding. Change oil and leave one quart low. Add last quart after the repair is complete


 Steel Seal Recommended Dose

4 cylinder engine – 1 Bottle (4 Cylinder Kit)

6 cylinder engine – 2 Bottles (6-8 Cylinder Kit)

8 cylinder engine – 2 Bottles (6-8 Cylinder Kit)


  1. Make sure engine is cold and remove the radiator cap. Pour Steel Seal directly into the radiator. Replace radiator cap and tighten.

  3. If vehicle is roadworthy: Start engine and drive at freeway speeds for 5 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. Top up with antifreeze/water as necessary, replace radiator cap tightly.

  5. Leave the Steel Seal in your system drive the vehicle as usual.


NB. If you are introducing Steel Seal via an surge / expansion tank please make sure that there is sufficient room for Steel Seal to go directly into the cooling system and that it does not just sit in surge / expansion tank reservoir.

For best results:

If you have tried inferior products flush your cooling system with clean water after disconnecting bottom radiator hose. Do not use a flushing agent.

If you have flushed system reconnect bottom radiator hose.


These directions are for people that have a lot of back pressure building up in the cooling system, usually shown as bubbling in the header tank or air forcing past the coolant cap.

Locate the cylinder causing the bubbling in the overflow tank or backpressure. (Remove plugs one at a time till bubbling stops)
Before starting the engine, remove the spark plug or injector from the cylinder that was causing the bubbling in the overflow tank or back pressure. If accessible, remove injector wire from that cylinder. This will limit the amount of unburned fuel going into the combustion chamber.
If you cannot find the spark plug/cylinder that is causing the back pressure, run the engine with the coolant level down to the top of the radiator core and with the radiator cap off or leave the expansion cap off the expansion bottle with water only just visible.
Make sure to run the engine up to temperature with the spark plug/Injector out and for the one final time with the spark plug/injector back in place.


Prestone Low-Tox—– (Propylene Glycol pH 8-11) — Biodegradable/non-toxic antifreeze.

available at O’Reilly Auto parts.

Prestone conventional green antifreeze – (Ethylene Glycol— pH 8-11) Low solvent effect, silicate stabilizers and high pH provide the best protection



Phone: Toll Free 855-771-1972




Steel Seal Frequently asked Questions

What is the background of the Steel Seal™ product?

The Product was developed in the USA and has been through some very strict independent and laboratory testing. Scott Laboratory has performed a thorough evaluation of both Steel Seal™ and its competitors and found Steel Seal™ to be superior to all products tested. Steel Seal™ has been used successfully in 100s of 1000s of vehicles. Steel Seal has been on the market since November of 1999. It rolled out by sending 80,000 infomercial style videos to nearly every mechanic shop in the states. This was followed with advertising in Motor Age, Motor, Underhood Service, Auto Remarketing, Used Car News, Used Car Dealer and Tech Shop. The combined circulation of these magazines literally reaches nearly every shop manager, mechanic and used car dealer in the United States. The major advantage of Steel Seal is the durability of the seal. The formula creates a seal that on a molecular level is close to the various types of metals in an engine, so that the seal will expand and contract at a similar rate with the engine. This has led to excellent repair longevity.

What is Steel Seal™ made of?

Steel Seal™ is made of several chemicals that, when combined under the right circumstances, creates a permanent seal as strong as steel.

How does Steel Seal™ work?

Once the engine is started and reaches operating temperature, Steel Seal™ is distributed through the engine. The product is drawn into the damaged area and seals the crack with a thermo-chemical bonding action process. This is similar to that of an epoxy resin just in liquid form!

Will Steel Seal™ clog the engine’s cooling system?

Steel Seal™ is a clear formula that contains no fibrous materials or particles that could clog engine coolant passages. You can see that for yourself just look through the bottle.

How long will Steel Seal last?

With Steel Seal™ the seal is permanent under normal operating conditions, but there is always the possibility of another leak in another part of the engine.

Is Steel Seal a scam?

No, Steel Seal is not a scam and we offer an easy to claim money back guarantee please speak to one of our many stockists to see how confident they are in the product.

What do I do if I have used an inferior or other product making similar claims?

There are several good quality products on the market such as K-Seal, Holts Radweld and Seal up however they all rely on fillers unlike Steel Seal and can therefore break down. The cooling system must be flushed thoroughly with water, NOT a flushing agent.

Are there any special precautions I should take when using Steel Seal™?

Steel Seal™ should be kept out of reach of children. Avoid eye or skin contact. If eyes or skin become irritated with Steel Seal™, rinse with cold water immediately. If swallowed, do not induce vomiting. Call a physician immediately.

What kind of head gasket symptoms will Steel Seal fix?

  • White smoke out of the tailpipe
  • Water in the oil
  • External leaks and leaking freeze plugs
  • Overheating
  • Backpressure / Bubbling in the radiator

What kind of vehicles can Steel Seal be used on?

Any type of closed, water cooled engine can be fixed with Steel Seal, whether it’s gasoline or diesel.
We’ve fixed cars, trucks, motorcycles, boats and heavy equipment.

What will Steel Seal™ not fix?

Steel Seal™ will not seal leaks in hoses, seals, water pumps, or extremely large cracks in the head or block resulting in the vehicle not starting. If it does not run Steel Seal cannot work as it relies on temperature.

How much do I need?

  • 4 cylinder engine – 1 Bottle (4 Cylinder Kit)
  • 6 cylinder engine – 2 Bottles (6-8 Cylinder Kit)
  • 8 cylinder engine – 2 Bottles (6-8 Cylinder Kit)

Should the coolant system be drained prior to use?

As part of the pretreatment procedure the antifreeze should be drained and replaced with water.

I’m trying Steel Seal for a second time as my cars still overheating, do I need fresh coolant?

If the coolant was fresh and clean add Steel Seal, if dirty, flush it first.

My vehicle is leaking oil at the head gasket?

Steel Seal will not fix oil leaks, only coolant related leaks on the head gasket.
Nothing stops head gasket oil leaks but replacing it.

Steel Seal never works, it’s fake!

It certainly can work, but of course no sealer can always work, occasionally the holes can be too big.

If you have any Questions please call us and we will be happy to help:

Phone  855-771-1972

Or send us a message or view our contact details here: CONTACT US