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Intake Valve


Intake Valve allows the fuel-air mixture to suck inside the cylinder for the first stroke.

  • During the intake stroke of a spark-ignition engine, the piston is moving down. The intake valve is open. The air-Fuel mixture flows through the intake proper and into the cylinder. The fuel system will supply the mixture. As the piston passes through the bottom dead center the intake valve closes. This seals off the upper end of the cylinstroke of a spark-ignition engine, the piston is moving down. The intake valve is open. The air-Fuel mixture flows through the intake proper and into the cylinder. The fuel system will supply the mixture. As the piston passes through the bottom dead center the intake valve closes. This seals off the upper end of the cylinder. 
  • Most engines have two holes or ports. in the upper enclosed end of the cylinders. This consists of the intake port and exhaust port. Air fuel mixture flows into the cylinder through the intake port. Burned gases will leave the cylinder through the exhaust port.
  • The two ports are open only part of the time. The rest of the time they are closed by the intake and exhaust valve.