How Does a Car’s Engine Work?

A car’s engine is a complex machine, but it can be boiled down to a few basic principles.

The Four-Stroke Cycle

Most car engines use a four-stroke cycle. This means that each piston goes through four strokes in order to complete one power cycle.

1. Intake stroke: The intake valve opens, and the piston moves down the cylinder, drawing air and fuel into the cylinder.
2. Compression stroke: The intake valve closes, and the piston moves up the cylinder, compressing the air and fuel mixture.
3. Power stroke: The spark plug ignites the air and fuel mixture, and the expanding gases push the piston down the cylinder, creating power.
4. Exhaust stroke: The exhaust valve opens, and the piston moves up the cylinder, pushing the exhaust gases out of the cylinder.

The Parts of an Engine

The main parts of an engine include the following:

• Pistons: The pistons are the moving parts that go up and down inside the cylinders.
• Connecting rods: The connecting rods connect the pistons to the crankshaft.
• Crankshaft: The crankshaft is the rotating shaft that turns the wheels.
• Camshaft: The camshaft is the shaft that opens and closes the valves.
• Valves: The valves control the flow of air and fuel into and out of the cylinders.

How an Engine Works

When you start your car, the starter motor turns the crankshaft, which in turn turns the camshaft. The camshaft opens and closes the valves, allowing air and fuel to enter the cylinders and exhaust gases to exit the cylinders.

As the pistons move up and down, they compress the air and fuel mixture. The spark plug then ignites the mixture, and the expanding gases push the pistons down. This motion turns the crankshaft, which in turn turns the wheels.

Conclusion

A car’s engine is a complex machine, but it is based on a few simple principles. By understanding how an engine works, you can better appreciate the engineering marvel that is your car.