What Is a Head Gasket? (And 9 Other Things To Know)

As one of the most essential parts of your car - and one of the parts most likely to fail - you need to know how to take care of your head gasket. Without a functioning head gasket, you won’t get anywhere fast - not to mention the potential damage this could do to your engine.

Read on to learn ten useful pieces of information about your car’s head gasket, starting with the terms you need to know.

 

Glossary

Internal Combustion Chamber - Fuel and air are burned off inside of the combustion chamber. The chamber is made up of the cylinder head, cylinder walls, and piston. 

Cylinder Head - The cylinder head creates the combustion chamber by sealing the top of the cylinder. It contains passageways which allow coolant and oil to travel safely. 

Engine Block - The engine block houses the main parts of the internal engine. This includes the crankshaft, cylinders, and water cooling system. The engine block is made from a strong metal, which gives it the ability to transfer heat from the combustion process over to the main cooling system. 

 

What Is a Head Gasket?

The head gasket in your car helps to seal the internal combustion chambers, thereby preventing fluids such as the coolant and oil from coming in contact with one another. 

By sealing the internal combustion chambers, your head gasket helps the fuel ignition process to run smoothly.

However, your head gasket may fail if it overheats, or if it has been incorrectly installed. It's always best to invest in a quality head gasket, and have this fitted by a professional mechanic.

 

What Is My Car's Head Gasket Made From?

Head gaskets can be made from a range of materials, including copper, steel, and Elastomeric. Each material offers certain benefits in terms of the function of the head gasket. 

Multi-layer steel head gaskets are the hardest to install, but they provide a great deal of durability and thermal conductivity. Copper is the material used most often in modern cars, but it is likewise not that easy to install.

By contrast, Elastomeric head gaskets are much easier to install, though they offer less durability overall.

 

Where Exactly Is The Head Gasket?

Your car's head gasket is located between the cylinder head and engine block. In order to take a look at it, a mechanic will need to remove the cylinder head and other engine parts to gain access. This is the most challenging part of the head gasket replacement process, as a professional mechanic needs to find the head gasket, which is buried deep within the engine. 

 

Why Is My Car's Head Gasket Important? 

As your car’s engine is split into two parts - the engine block and the cylinder head - your head gasket is essential in protecting all of the components that reside within these halves. 

The cylinder head contains the valves and spark plugs, and is located on top of the cylinders which are found in the engine. The engine block contains pistons and connecting rods, and is sealed to the cylinder head by the head gasket. 

Your head gasket is incredibly important, as it seals the engine’s combustion chamber. This helps to build the right level of compression as generated by the ignition, thereby maintaining engine power. Your head gasket also matters because it separates the oil and water which circulate around the engine block and cylinder head - two liquids that you don’t want to mix.

 

What Are Some Common Engine Block Problems?

Coolant Leak - An external coolant leak may occur if the engine block is damaged due to overheating or freezing temperatures. Likewise, you may notice that fluid is leaking from your car if there is a leak present in the water pump. 

An internal coolant leak can be caused by a damaged head gasket, as this may lead to water and engine oil mixing. If oil and water do come into contact with one another, this can cause serious damage to your engine.

Perforated Engine Block - When your head gasket is made incorrectly, this can cause the cylinders to crack. This happens as a result of holes appearing in the casting, due to contaminants that were present during the manufacturing process. 

 

Why Does Head Gasket Failure Occur?

Head gasket failure is most often caused by overheating, so it is best not to drive when you suspect your car is overheating. Your head gasket may fail if combustion gases are able to leak out, or indeed if coolant is able to leak in.

Being aware of the health of your cooling system can also help you to avoid head gasket failure. There are a few ways that you can look after your cooling system:

• Top coolant up to the appropriate level
• Check for leaks
• Check that the fan is working 
• Check that the radiator is working

By doing these simple checks, you can help your vehicle to maintain a normal temperature.

 

Should I Be Using Head Gasket Sealer?

Head gasket sealer is a substance which you can pour into your radiator. After leaving the car to run for between 15 and 30 minutes with the heater and fan on at a high temperature, these sealants will heat up and begin to fill any small cracks in the head gasket. Whilst these sealants will harden in the cracks, this can only really be seen as a temporary fix.

Ultimately, a head gasket replacement is the only real solution if you are experiencing problems. If you want to stay safe, then let a professional mechanic put your mind at ease by taking a look at your head gasket for you. It may be a costly replacement if needed, but it is better to do something at the first sign of trouble, than wait and deal with an even more costly repair later down the line. 

 

 

What Happens During a Head Gasket Replacement?

As the head gasket is difficult to access, the mechanic will first need to remove the battery and the engine. They will also need to drain off the engine oil and coolant. This process will vary depending on the specific model in question. 

The mechanic will then remove your old head gasket, and clean and prepare the area so that the replacement head gasket can be fitted. Your new head gasket will be fitted, with sealer being used to close any small gaps as the mechanic sees fit. The mechanic will also reassemble the engine and any related parts that were removed during the process. 

As you can imagine, this is a time-consuming process. Whilst the price of the head gasket itself may not be astronomical, it is the labour costs that will drive up the price. That's why it is essential that you do everything you can to keep your head gasket in good condition - your car may never even need a head gasket replacement if you know how to take care of it!

 

What Can I Do To Prevent a Blown Head Gasket? 

The best thing you can do when it comes to all aspects of your car is to take preventative measures to keep your vehicle in good condition. Especially in the current cost of living crisis, it is understandable now more than ever that you might want to avoid an unexpected and potentially expensive repair. 

Here is a list of steps you can take to further the lifespan of your car’s head gasket:

• Use high-quality coolant
• Book in for a car service regularly
• Inspect and replace belts and hoses when needed
• Make sure your head gasket is properly installed

Now that you know more about your car’s head gasket, is it time that you had yours checked by a professional mechanic? Book a visual inspection through BookMyGarage, and get your car running safely and smoothly today.