How a Car Engine Works: 4 Stroke Petrol Engine

Introduction

A car engine is a complex machine that converts the chemical energy stored in petrol into mechanical energy that can be used to power the car. The most common type of car engine is the four-stroke petrol engine, which operates on a four-step cycle:

1. Intake stroke
2. Compression stroke
3. Power stroke
4. Exhaust stroke

Intake Stroke

The intake stroke begins when the piston is at the top of the cylinder. The intake valve opens, allowing air and fuel to enter the cylinder. The piston then moves down the cylinder, drawing the air and fuel into the cylinder.

Compression Stroke

Once the piston has reached the bottom of the cylinder, the intake valve closes and the compression stroke begins. The piston moves up the cylinder, compressing the air and fuel mixture. This compression increases the temperature and pressure of the air and fuel mixture, making it more likely to ignite.

Power Stroke

At the top of the compression stroke, the spark plug ignites the air and fuel mixture. The burning gases expand, pushing the piston down the cylinder. This downward movement of the piston is converted into rotational motion by the crankshaft.

Exhaust Stroke

Once the piston has reached the bottom of the cylinder, the exhaust valve opens and the exhaust stroke begins. The piston moves up the cylinder, pushing the exhaust gases out of the cylinder and into the exhaust system.

Conclusion

The four-stroke petrol engine is a complex machine, but it is an essential part of any car. By understanding how a car engine works, you can better understand how your car operates and how to maintain it.

YouTube Video

Here is a YouTube video that provides a visual explanation of how a four-stroke petrol engine works: