What is a Cylinder Head Gasket?

Categories: Cylinder Head Tips

Cylinder head gaskets are an important part of any vehicle with a combustion engine. This vehicle part dates back decades and often needs replacing after some time in many cars on the road today. To help you discover the importance of your cylinder head gasket, we’re here to share everything you need to know about this part, who invented it, and what to do if you find your gasket is failing.


Why Cylinder Head Gaskets are Critical

A cylinder head gasket offers a seal between your engine block and the cylinder head. It is a thin, flat piece of material that sits between the engine block and the cylinder head. The gasket forms a seal between these two engine components, preventing engine coolant, oil, and combustion gases from leaking out of the engine. If you do have a leak, then it may lead to your engine overheating or running poorly, which is something you don’t want to experience.

Cylinder head gaskets are crucial to maintaining engine compression. The gasket is designed to seal off the combustion chambers to prevent compressed air and fuel from escaping. This compression is essential for the proper functioning of the engine, as it allows the fuel to burn more efficiently and produce power.

Cylinder head gaskets are typically made from strong materials, such as graphite, metal (often steel), or a combination of both. The gaskets must be able to withstand very high temperatures and pressures without degrading or failing, which can cause severe engine damage or total engine failure. In the event of a blown head gasket, coolant and oil can mix, causing engine overheating and further damage if the issue is not addressed quickly.


Who Invented the Cylinder Head Gasket?

The inventor of the cylinder head gasket was Aukers Albert John, who applied for the patent for the part back in 1944. The application was filed by Victor Manufacturing and Gasket Co and this part has been integral to engines over the years. We also need to recognize a British engineer named Frederick Richard Simms (he was also the founder of the Royal Automobile Club)  whose inventions in the late 19th century played a key role in the early development of the automotive engine and overall auto industry.


Types of Cylinder Head Gaskets

There are many different types of cylinder head gaskets, but you’ll find that multi-layer steel ones are the most commonly used option. These types of gaskets have between two and five layers of steel with elastomer used as well. Other materials that are used include solid copper, composite, elastomeric, and O-ring gaskets made from steel or copper. Asbestos gaskets are very rarely used today due to their health risks, but they were quite common in the past.


  • Composite gaskets: These gaskets are made of multiple layers of materials, such as graphite, rubber, and steel. Composite gaskets are quite durable and can withstand very high compression and temperatures.


  • MLS (multi-layer steel) gaskets: These gaskets are constructed of multiple layers of steel with a sealing coating applied to each layer. MLS gaskets are known for their strength, and they are a popular choice in high-performance and sports car engines.


  • Copper gaskets: Copper gaskets are made entirely of copper, and they are known for their excellent heat conductivity. Copper gaskets are softer than steel gaskets, which allows them to conform / adhere to the surface of the cylinder head better and create a tighter seal. These types of gaskets are frequently used in high-performance and racing engines.


  • Rubber / Elastomeric gaskets: Rubber gaskets are made of rubber or silicone, and they are an affordable option for lower-performance engines. These gaskets are made of rubber or silicone and are designed to be used in engines that have uneven or warped cylinder head surfaces. However, they are not as durable as composite or MLS gaskets.


  • Coated gaskets: These gaskets are made of a composite material, but they have a specialized coating, such as silicone or Viton, applied to the surface to provide extra sealing properties.


  • Fiber / Asbestos gaskets: These gaskets are made of materials, such as cellulose or asbestos and are typically used in older engines / found in classic or antique cars.


Is a Cylinder Head the Same as a Head Gasket?

The cylinder head is the part that is considered to be the top section of the engine, whereas the lower part would be called the engine block. The gasket is referring to the seal that’s used on the cylinder head, making it an important part of this engine component. While the cylinder head and head gasket are both important components in an engine, they serve different functions and are separate parts that can be replaced independently of each other if needed.


What Happens When The Cylinder Head Gasket Fails?

If your cylinder head gasket fails, then it requires your vehicle engine to work much harder in order to create the power needed for your vehicle. You might notice that your vehicle’s MPG drops significantly if your gasket is damaged.

When a gasket is totally blown, you may find that the vehicle loses coolant, so it doesn’t perform at its best and could overheat. One risk is that you could blow the cylinder head gasket, which can happen when you start your engine. If you put your foot down quickly, the shock on a cold engine can result in this failing. Your cylinder head gaskets will contract and expand based on the engine temperature. We don’t recommend driving with a blown head gasket, as your engine may overheat and the pressure within the combustion chamber is decreased, leading to a reduction in power. Driving with a damaged gasket is also a good way to waste money on gasoline.


  • Loss of Compression: One of the most significant effects of a failed cylinder head gasket is a loss of compression in one or more cylinders. This compression loss can cause a significant reduction in engine power and can cause the engine to run poorly or not start at all.


  • Overheating: The cylinder head gasket also helps to maintain the proper flow of coolant through the engine. When it fails, coolant can leak into the cylinders, and the engine may overheat. This overheating can cause severe engine damage if not addressed promptly.


  • Oil Contamination: Failure of a cylinder head gasket can also allow oil to leak into the combustion chamber. This leakage can cause oil to mix with the fuel, leading to increased emissions and reduced engine performance. It can also cause damage to the catalytic converter over time.


  • External Leaks: In addition to internal leaks, a failed cylinder head gasket can also cause external leaks. This leakage can result in oil or coolant leaking onto the ground (check your garage floor), causing a mess and potentially damaging other components of the engine or surrounding areas.


In short, a failed cylinder head gasket can cause a wide range of issues, from loss of engine power to severe engine damage. If you suspect that your cylinder head gasket has failed or is damaged, then it is essential to have it repaired and/or replaced by a qualified local mechanic as soon as possible.


How Many Hours or Days Does It Take To Fix A Cylinder Head Gasket?

It takes between six hours and a few days to fix or replace a cylinder head gasket. This time estimate will naturally depend on how severe the failure is, but it can be one of the biggest issues you’ll ever experience as a driver / vehicle owner. The most important thing is not to rush this replacement, as you will likely only mask the issue not completely fix it. While you could try to replace the gasket yourself, if you aren’t experienced at this type of engine repair, then it’s always best left to a professional.


How Much Does It Cost to Replace a Cylinder Head Gasket?

A cylinder head gasket will usually cost between $1,000 and $2,000 to replace. Many people end up scrapping their vehicle if it’s quite old – if this repair becomes too costly – you will want to make that decision for yourself. The parts aren’t necessarily the biggest expense of this replacement, but the time and expertise needed to complete the work is what makes it cost more than you might expect. You might also want to consider just replacing the whole engine, as there may be damage to the engine from the blown head gasket. Work with a mechanic to figure out the best option for your needs, which may include replacing the entire engine or your vehicle if it’s at the end of its life.


Cars Most Likely to Need a Head Gasket Replacement

Some vehicles are more likely to need a head gasket replacement, and it’s important to keep this in mind when buying a new or used car. There are many vehicles on the market today with a lot of reports about blown head gaskets, but mechanics are very used to replacing these parts. The following vehicles often come up in lists of most likely to need a replacement:

  • 2011 Chevrolet Cruze
  • 2011 BMW 3 Series
  • 2012 BMW 5 Series
  • 2011 Buick Lucerne
  • 2012 BMW X3
  • 2014 BMW X1
  • 2011 Subaru Impreza
  • 2013 Mini Cooper

YouTube Video References

Are you looking to learn more about cylinder head gaskets? If so, there are some great videos online today which will help guide you through the replacement process. This video offers you a tutorial on how to correctly fix a blown gasket, which could save you a lot of money if you feel up to the task. Here is another great video about replacing a cylinder head gasket, giving you an insight into this process. Of course, we recommend outsourcing this work if you don’t feel like you can do it yourself, as you don’t want to cause further damage to your engine.

As you can see, the cylinder head gasket is an integral part of your engine. We recommend keeping an eye on this part throughout your engine’s life, as failure is very common within many different types of vehicles. While some vehicles are more susceptible to issues in this area than others, you might find yours fails at any time. The good news is that it can be replaced if needed, which you can either try to do alone or work with a trusted local mechanic to complete the task.


Cylinder Head Gasket Repair Experts

Since repairing bad cylinder head gaskets is not a typical DIY project, we recommend that you consult with a professional auto parts company. Clearwater Cylinder Head (CCH) is an experienced (over 25 years) auto parts company focusing on cylinder heads. We specialize in providing quality and warranty-backed rebuilt cylinder heads for a wide range of vehicles. With a gigantic online catalog of cylinder heads, we likely have the cylinder head components you need to repair your car, truck, heavy machinery, or boat. The knowledgeable employees at CCH look forward to helping you find the right cylinder head solution for your vehicle. Please contact Clearwater Cylinder Head by phone at 800-572-1963.