Skip the auto shop - Our mechanics make house calls

What Is the Purpose of Engine Gaskets?

engine gasket

It is estimated that more than 250 individual components make up the typical combustion engine used in today's cars, trucks, and SUVs. But did you know that one of the most important components are the gaskets that are installed in-between two other parts? Although they are small in size and not particularly complex, they are vital to engine function.

There are several different gaskets that are used in various parts of the engine. Some gaskets are inside the motor, while others connect the engine to supporting components like the intake manifold, exhaust manifold, and water pumps. Their primary job is to keep debris from entering the engine, maintain a consistent internal pressure, and keep oil and other fluids inside the engine. Here are a the most important gaskets on your engine and why they are critical in keeping it running.

Cylinder Head Gaskets

Often known simply as the head gasket, the cylinder head gasket prevents combustion gases from getting into the coolant system. They are made typically of copper and are placed between the [cylinder head](https://www.yourmechanic.com/article/how-to-clean-cylinder-heads-by-spencer-clayton] and the engine block. The thickness of the head gasket can impact the compression ratio inside the combustion chamber. On older vehicles, head gaskets had a ‘shelf life’ and would wear out, especially closer to the edges of the combustion chamber due to high heat. This would reduce the pressure inside the combustion chamber and lead to potential engine failure.

Although today’s head gaskets are much better in design, one problem they still have is being damaged during overheating situations. When a head gasket fails, coolant will seep into the combustion chamber and mix with engine oil. This can cause significant engine damage and require complete engine rebuild or replacement.

Intake and Exhaust Manifold Gaskets

The intake manifold gasket regulates the temperature inside the chamber and prevents air from escaping during combustion. This ensures the fuel mixture has the right amount of oxygen for the engine to perform efficiently. The exhaust manifold is similar, but is installed in between the cylinder head and the exhaust manifold. When these gaskets fail, they can create compression issues, and reduce engine efficiency. Typically these gaskets do not fail when a vehicle is properly maintained with routine maintenance.

Main Bearing Gaskets

The main bearing gasket is designed to keep the oil in the oil pan while the crankshaft is moving. It is set right off the last main bearing and is located on the rear of the engine. The gasket or seal is generally made of rubber or silicone to hold up to high temperatures. It keeps the oil from moving past the crankshaft while it spins. The main bearing seal will fail with excessive oil pressure, excessive heat, or the collection of engine sludge which is caused by not changing engine oil and filter as recommended.

Camshaft Gaskets

The camshaft also requires a gasket to prevent oil from leaking out. Also referred to as a cam seal, the round rubber gasket does double duty. It not only prevents oil from seeping out, but it keeps dust and dirt from getting into the engine and causing damage.

A faulty gasket can cause major damage over time if not replaced. Although a professional mobile mechanic can replace some external gaskets, internal engine gaskets should be replaced by a dedicated engine shop. It’s important to have a mechanic inspect the gaskets in the engine to know when they need replaced.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How to Get a Louisiana Driver's Permit
s licensing program. The first step in this program is to obtain...
P2422 OBD-II Trouble Code: Evaporative Emissions Control System (EVAP) Vent Valve Stuck Closed
Diagnostic Trouble Code (DTC): P2422 P2422 code definition Evaporative Emissions Control System (EVAP)...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...


Related questions

Q: Valve cover gasket 2012 Ford F-150

Hi - Here at YourMechanic, click here for guidance on how to make this repair. There are many other aftermarket sources for information on how to replace valve cover gaskets: the factory Ford Service Manuals, vendors of aftermarket service manuals...

Q: My engine won't crank.

Hi there. It sounds like the head gasket is burned between the combustion chamber and a water jacket. It may be a small leak to not get any in the oil. To check this condition, get a block test with...

Q: Engine knock, is it totally broken?

The engines in most of these cars are pretty noisy on start up and quiet down after a few minutes of running. If your noise is an engine lower end knock and not a lifter noise, or if the noise...