How to Guides

How To Replace A Head Gasket

Zaki Moulvi posted this on Jun 9, 2014

A blown head gasket in your engine is not sometime to be taken lightly.  While we usually equate a gasket to just being a seal, the head gasket seals to major engine components, the cylinder head and the engine block.  The cylinder head is home to the valves, while the engine block holds the crankshaft and the pistons. 

A leak in the head gasket ranges in severity.  Minor ones will only make your car guzzle up motor oil or engine coolant while a major one could cause the two fluids to mix together.  When this happens there is going to be no lubrication for the crankcase.  Compression issues can also occur making it difficult for you to control your vehicle.  

Symptoms of a Blown Head Gasket

  • Unexplained oil loss:  The cylinder head contains a number of passages that allow for motor oil to lubricate the moving parts.  The head gasket acts as a seal, preventing the oil from entering the engine block.  When the head gasket is leaking, the oil is allowed to pass through and will be burnt off.  Your car will idle poorly and give off an exhaust that is bluish-white in color.
  • Unexplained engine coolant loss:  Dozens of passages are inside of the cylinder for liquid coolant to pass through.  The head gasket is in place to prevent that fluid from entering into the combustion chambers.  If it does, your exhaust will be steamy or you will see water dripping from the tail pipe.  You will also see bubbles inside the coolant reservoir coming from the engine inlet.

Worst case scenario:  If motor oil and engine coolant combine, the integrity of the oil is compromised and the engine parts are not being lubricated properly.  It is as if you mixed your motor oil with water.  The viscosity is changed completely.  Bearings and other vital parts are compromised as hot metal parts are colliding with each other.  Pull out the engine oil dipstick. If it is brown, bubbly or has traces of water stop driving the car until you have had the head gasket replaced.

Tools For the Job:

  • A new head gasket.  This part is vehicle specific, so be sure to order yours through a reputable dealer like
  • Wrench set
  • Pry bar
  • A room temperature vulcanant, or RTV.  This is a specialized sealer that allows you to extend the head gasket in small areas.  You can get this from as well.
  • Small scouring pad
  • Work gloves

Getting the Job Done:

The first thing you are going to want to do is consult your owner’s manual to see exactly where your head gasket is.  They are usually buried deep inside of your engine, with a bunch of parts in the way.  Be prepared to remain multiple engine components before you can even get started with the head gasket.  Since reassembly may seem like a puzzle, use your cell phones camera to take pictures of each pieces position before removing it, and be careful to keep all mounting hardware with the right part.  This will be very helpful when it comes time to put it all back together.

Once you have gained access to the cylinder head, you can use your wrench to remove the bolts and carefully lift the head away from the engine block.  You may need to use the pry bar to actually remove the head gasket.  Use the scouring pad to remove any left-over sealant and debris to ensure that you have a good seal when you install the new head gasket.

Place your new gasket firmly onto the head and check that the seal is tight.  There cannot be any gaps.  If you are having trouble getting some areas to connect, use the RTV sealant.  Reattach the head to the engine block, checking for and correcting gaps consistently.

The next step is to put all of the other components back in place.  Take your time and be careful when handling delicate car parts.  You don’t want to have another repair job on your hands before you finish this one.  Replacing a blown head gasket is normally done by a professional mechanic so if you did yours successfully, you deserve a good pat on the back.

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