The internal combustion engine has many components attached to the engine block designed intricately to work in unison in order to create power for the motor vehicle. A valve is a device designed to open and seal an aperture.

Inside the internal combustion engine, the valves can be found connected to the cam shaft, which coordinates and drives the opening and shutting of the valves inside the combustion chamber. The intake valve opens to allow the fuel mixture into the combustion chamber. The fuel mixture at this point is below atmospheric temperature. The intake valve then closes as the fuel mixture is compressed by the piston. As the fuel mixture is squeezed, ignited and burned, the piston then draws away to allow the exhaust valve to open. This is so that the burnt gases exit the combustion chamber, and then the exhaust valve will close again, making the way for the entire cycle to happen again and again.

The internal combustion engine valves have a tremendous task to perform under immense pressure and scaringly hot conditions, particularly the exhaust valves which open and close there aperture at temperatures reaching 1000°F.

If an engine is operating at 3000 rpm, the valves can be lifted off their seats 1500 times each minute. Wow! Bet you couldn’t get off your seat that many times per minute!We hope that helps answer the question ‘What is What is a Valve?’!

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