How Four Stroke Engine Works

We know that cars are powered by engines, but how do they do this? The rotating motion of an engine's crankshaft is transmitted to the wheels by the driveshaft. The gearbox changes the number of rotations of the driven wheels during one turn of the crankshaft. In low gear, the output of the engine is high, but the speed is low. In high gear the car is faster and uses less fuel, but accelerates more slowly. The most common type of engine used in cars is the four-stroke auto engine. It converts the alternating vertical motion of the pistons into the rotation of the crankshaft. The crankshaft drives the driveshaft and the camshaft through the timing belt. The camshaft operates the valves, which ensure fuel intake and the expulsion of exhaust gases through a coordinated rhythmic opening and closing. The piston moves downwards, decreasing the pressure in the cylinder. The intake valve opens and a mixture of air and fuel flows from the carburetor into the cylinder. The second stroke is compression. Both the intake and the exhaust valves are closed. Then the momentum of the crankshaft and the counterweight causes the piston to move upwards, compressing the mixture of air and fuel and thereby increasing its temperature. The third stroke is the power stroke. The spark plug ignites the compressed heated mixture of fuel and air. The explosion pushes the piston down. The fourth stroke is the exhaust stroke. The piston moves upwards, the exhaust valve opens, and the exhaust gases are expelled. As you can see, the linear motion of the piston is converted into the rotating motion of the crankshaft in the engine. The energy necessary to move the piston is provided by the combustion of fuel. The fuel used in the four-stroke auto engine is petrol. An important attribute of petrol is the octane number. The higher it is, the higher its boiling point. Therefore, it can be compressed more, resulting in greater efficiency.