Difference Between Head Gasket And Valve Cover Gasket

When it comes to the maintenance and repair of your vehicle’s engine, confusing terms such as “head gasket” and “valve cover gasket” can be quite daunting. Although the two serve different purposes, they are often mistaken for each other. In this article, we’ll explore the difference between a head gasket and a valve cover gasket, and their unique functions.

Head Gasket

The head gasket is a critical component of your engine that seals the combustion chambers, prevents coolant and oil from mixing, and ensures that the engine runs smoothly. It is located at the point where the cylinder head and engine block meet. The head gasket forms a perfect seal between the two surfaces, and ensures that the coolant, engine oil, and combustion gasses do not leak out.

A head gasket is typically made of multi-layer steel, also referred to as “MLS,” and is designed to withstand high-pressure and extreme temperatures. As the engine runs, the head gasket is exposed to a wide range of temperature fluctuations, putting it under tremendous pressure. Over time, this exposure can lead to wear and tear, causing the gasket to crack, warp, or fail entirely. Failure of the head gasket can lead to a multitude of engine problems such as coolant loss, overheating, and even engine failure. If the head gasket fails, it is important to get it replaced immediately to prevent further damage to the engine.

Valve Cover Gasket

The valve cover gasket, on the other hand, seals the gap between the valve cover and the cylinder head. It is located at the top of the engine, and its primary functions are to prevent oil from leaking out and to keep debris and dirt from entering the engine. The valve cover gasket plays an essential role in protecting the engine from potential damage and keeping it running smoothly.

Like the head gasket, the valve cover gasket is also exposed to high temperatures and pressure. As a result, it can also wear out over time and lead to oil leaks. However, it is not typically considered a severe issue, and replacing the gasket is relatively easy and inexpensive compared to the head gasket.

Differences Between Head Gasket And Valve Cover Gasket

While the two gaskets may look similar, they serve different purposes and are located in different parts of the engine. In addition to their unique functions, there are several other differences between the head gasket and the valve cover gasket.

Material – As mentioned, the head gasket is usually made of multi-layer steel or graphite, while the valve cover gasket is commonly made of rubber, cork, or silicone.

Location – The head gasket is located between the engine block and the cylinder head, while the valve cover gasket is located at the top of the engine, between the valve cover and the cylinder head.

Function – The head gasket’s primary purpose is to prevent coolant and engine oil from mixing and to seal the combustion chamber. The valve cover gasket, on the other hand, is designed to keep oil in the engine and debris and dirt out.

Difficulty of Replacement – Replacing the head gasket is a complicated and expensive process, whereas replacing the valve cover gasket is relatively easy and inexpensive.

Importance – While both gaskets play a crucial role in engine performance, the head gasket is considered more critical than the valve cover gasket since it prevents significant engine damage.


In conclusion, the head gasket and valve cover gasket are two separate components that perform different functions in your engine, but both are highly essential for proper engine operation. Understanding the difference between these two gaskets will help you identify the issue in your engine and help you determine the necessary repair. Regular maintenance, timely replacements, and keeping track of any signs of wear and tear can extend the lifespan of your engine and save you a lot of money in the long run.