How To Fix A Blown Head Gasket Without Replacing It [Step By Step Guide]

Do you have a blown head gasket causing leaks in your engine, and you want to know how to fix it without replacing the gasket? You’ve come to the right place, for we have researched this question, and we have the answer for you.

Here is a summary of the steps that you need to take to fix your blown head gasket without replacing it.

  1. Replace the coolant with water.
  2. Start the engine.
  3. Pour head gasket repair liquid into the radiator.
  4. Let the engine idle for at least 50 minutes.

Get the detailed steps in the succeeding sections. Learn about the different causes of a blown head gasket and how to avoid them in the sections below.

Read on!

A cylinder block and a damage head gasket on the hand of a mechanic, How To Fix A Blown Head Gasket Without Replacing It [Step By Step Guide]

Head Gasket Failure And Its Causes

The head gasket is a simple yet important part of the engine.

Your engine has two major parts—the engine block and the cylinder head. Coincidentally, these two parts also divide the combustion chamber into two.

Short block with installed cylinder head gasket

The combustion chamber is where the engine burns the mixture of fuel and air at high pressures. The result of the combustion is the production of energy that is powerful enough to move your car and its passengers.

Therefore, it is important that the combustion chamber should be able to keep all the energy and pressure within, or your engine is just wasting fuel by leaking energy.

Moreover, the production of energy through combustion produces a large amount of heat and exhaust gases as by-products. There are multiple channels around the combustion chamber where coolant travels to keep the temperature within safe levels. Even metal is susceptible to extreme temperatures.

The constant movement of the components of the engine requires constant lubrication. Without lubrication, the friction generated by constant rubbing will wear out the components of the engine. There are channels for the oil to provide lubrication.

And the component of the engine that ensures that all of these components work the way they should and within their places is the head gasket.

So, what can cause the head gasket to fail?


Car engine overheating

Too much heat can damage anything. That includes the head gasket in your car.

Thus, it is not a surprise that it is the most common reason why head gaskets fail.

Too much heat in the engine can lead to temperatures that the head gasket can no longer handle.

Excessive heat can cause the head gasket to weaken and succumb to the pressure and energy that the combustion chamber produces. This leads to cracks and leaks in the head gasket.

Moreover, high temperatures in the combustion chamber can cause the engine to warp at the area where the cylinder head and the engine block meet. Warping around this area can prevent the head gasket from making a perfect seal. This will lead to leaks.

How to avoid engine overheating?

Maintaining the coolant level is the best way to prevent the engine from overheating. Check the coolant level regularly. If you’re starting to lose coolant, bring your car to a mechanic to look for leaks in the radiator.

Always monitor the temperature gauge while you’re driving. This will tell you if your engine is getting dangerously hot. Knowing the temperature will allow you to pull over and let the engine cool down before you continue driving.

Check the water pump for leaks regularly. A faulty water pump will prevent the coolant from getting to the radiator to cool your engine.

Check if your heater is blowing warm air or cold air. If your heater is blowing cold air, it is a sign that the water pump is not working. Have a mechanic check your water pump and make any replacements if necessary.


Pre-ignition in an internal combustion engine happens when the fuel and air mixture ignites before the spark plug activates. This can happen if the engine is too hot. The pressure inside the engine, combined with a high temperature, can cause the fuel and air mixture to spontaneously ignite.

Bad ignition timing and too much oxygen in the engine can also lead to a pre-ignition. This can cause the head gasket to fail.

The piston of the engine should reach the uppermost position before the fuel and air mixture ignites. The ignition will produce energy and push the piston downward.

However, if the piston is only halfway to the uppermost position when the fuel and air mix ignites, then the energy will have nowhere to go and force itself out through the gap between the cylinder head and the engine block. This is where you will find the head gasket.

Pre-ignition will damage various components of the engine, including the head gasket.

How to prevent pre-ignition?

Bring your car to a mechanic to check the camshaft timing and make the necessary adjustments.

Camshaft valve adjustment

Sudden Temperature Changes

All materials expand and contract with temperature changes. Sudden temperature changes can weaken materials and can eventually damage them.

The head gasket can drop in temperature to match the surrounding air during winter. When you turn on the engine and suddenly step on the gas during cold months, the temperature of the engine will suddenly jump up.

The sudden temperature change will cause the head gasket to rapidly expand. This will weaken the head gasket and damage it.

How to prevent sudden changes in the temperature of the head gasket?

Let your car gradually reach the operating temperature during winter before you start to do any aggressive driving. Waiting to reach the correct operating temperature allows your engine to warm up slowly and prevent issues from sudden temperature changes.


As your head gasket ages, it will also start to weaken. If your car has significant mileage, the head gasket will be due for a replacement. It is a good idea to replace the head gasket before it starts giving you any problems.

A leak in the head gasket can lead to problems in the engine that is more expensive to repair than replacing an aging head gasket.

How to fix a head gasket without replacing it?

You can fix head gaskets with small leaks without replacing them. However, you should replace head gaskets that have significant damage. The method below can only repair head gaskets that are just starting to leak.

Moreover, you must go over the list of possible reasons above that cause blown head gaskets. You will have the same issue again very soon unless you address the underlying problem.

Preparing Your Car

  1. Park your car on a level surface and turn off the engine.
  2. Activate the parking brake.
  3. Place your car in Park(P).
  4. Jack your car at the jacking points.
  5. Place jack stands on the jacking points.
  6. Release the jack and raise it again until it is just barely touching the jacking point. This will serve as a backup in case the jack stands fail.
  7. Give your car a shake to test the stability of the jack stands.
  8. Open the hood of your car and disconnect the battery cables. This will prevent any accidental electrical discharge while you work on the head gasket.

BIG RED T41202 Torin Steel Jack Stands are available on Amazon through this link.

Draining The Coolant

Make sure that the engine is cold before continuing with the steps below.

  1. Wear safety equipment. The contents of your radiator and the head gasket repair fluid can irritate the skin and eyes.
  2. Place a drain basin under the radiator.
  3. Get under your car and unplug the radiator drain. This will flush the coolant from your car. Wait until you drain all the coolant.
  4. Uninstall the thermostat. You can find this along one of the tubes that connect the engine and the radiator.
  5. Fill your system with water, then empty it. Do this at least twice to rinse off any coolant residue inside the engine.
  6. Close the radiator drain valve.

Applying The Head Gasket Repair Fluid

  1. Fill your system with water. Leave enough room for the head gasket repair fluid
  2. Remove the radiator cap and set the heater to full.
  3. Reconnect the battery cables.
  4. Start the engine and let it idle.
  5. Slowly pour the head gasket repair fluid into the radiator while the engine is running.
    • It should take you at least one minute to empty the contents of the whole bottle into the radiator.
  1. After you empty the whole bottle, reinstall the radiator cap.
  2. Let your car idle for at least 50 minutes with the radiator cap on.
  3. Turn off the engine after the time is up.
  4. Disconnect the battery.

Bar's Leak HG-1 Head Gasket Repair Fluid is available on Amazon through this link.

Finishing Up The Fix

  1. Let the engine cool down once more.
  2. Once the engine is cool enough, install a new thermostat.
  3. Remove the radiator drain cap.
  4. Drain the water from your system.
  5. Close the radiator drain valve.
  6. Release the jack stands and then lower your car.
  7. Reconnect the battery.
  8. Pour in a pre-diluted coolant until it reaches the appropriate level.
  9. Start the engine and let it idle.
  10. Check the coolant level. Running the engine will release air bubbles from inside the system. Refill the coolant up to the correct level.

Dorman 902-3036 Engine Coolant Thermostat is available on Amazon through this link.

Valvoline 50/50 Prediluted Antifreeze/Coolant is available on Amazon through this link.


Sealing gasket in hand

You can fix small leaks in the head gasket using a head gasket repair fluid.

If you enjoyed reading this article, you might find the articles below equally enjoyable to read:

Should I Use Copper Spray On My Head Gasket [& How To]?

Can You Reuse A Head Gasket? Should You?

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