Four Stroke Petrol Engine

This engine is work in the cars, truck, motorcycle, aircraft, machinery and many others, most commonly use a four stroke cycle. -The four stroke refer to intake, compression, combustion and exhaust strokes that occur during two crankshaft rotation per working cycle of the gesoline engine and diesel engine. + CYCLE -The cycle begins at top dead center.When the piston is fartherest away from the axis of the crankshaft a stroke refers to the fall travel of the piston from top dead to bottom dead center.

• INTAKE STROKE(SUCK) on the intake or indunction stroke of the piston , the piston descends from the top of the cylinder to the bottom of the cylinder reducing the pressure inside the cylinder. A mixture of fuel and air is forced by atmospheric pressure into the cylinder though into the cylinder though the intake port. The intake valve then close.

• COMPRESSION STROKE With both intake and exhaust valves closed the piston returns to the top of the cylinder compressing the fuel air mixture. This is known as the compression stroke.

• POWER STROKE While the piston is close to top dead center, the compressor air fuel mixture is ignited, usually by a spark plug. Compressed fuel air toward bottom dead center with treamendous force. This is known as the main source of the engine's torque and power.

• EXHAUST STROKE during the exhaust stroke, the piston once again returns to top dead center while the exhaust valve is open. This action evaluates. The products of combution from the cylinder by pushing the spent fuel air mixture through the exhaust valve.