How a Crankshaft Works In An Engine

Wondering how a crankshaft works in an engine?

The crankshaft is one of the most important parts of your vehicle’s engine. This part turns linear energy into rotational energy.

Simply put, it allows the wheels of the vehicle to turn so that the vehicle can drive forward. The crankshaft works alongside other parts so that the engine runs. The engine’s pistons attach to the crank, which connects to the flywheel. When these parts move together, the result is wheels that turn as the car moves.

Now that you know what this part is, let’s find out more about how the crankshaft works in an engine.


The position of the crankshaft is important because this part enables all connected parts to work together. To allow parts to do this, the crankshaft is positioned beneath the engine’s cylinders.

This position may vary slightly depending on the type of engine. It is positioned between cylinder banks on flat engines. It is at the base of V-type engines.

There can be as many as 12 cylinders in an engine. Most vehicles have four cylinders. Pistons are situated inside each of these cylinders.

These connect to the crankshaft on separate rods. They are moved up and down in a movement that is powered by the crankshaft.

Four-Stroke Cycle

As the pistons move up and down inside each cylinder, the cylinders move along with the rest of the engine in what is known as a four-stroke cycle. This cycle happens in each cylinder. It is essentially the motion that powers the engine. The strokes in order are intake, compression, power and exhaust.

The cycle starts on the intake stroke. Here, the intake valve opens as the piston comes down the cylinder. When the piston reaches the base, the intake valve closes, retaining a mixture of air and petrol inside the cylinder.

As the piston moves back up the cylinder, this mixture of air and petrol is compressed by the piston, leading to the second stroke – compression.

In the next stroke, the spark plug ignites the petrol-air mixture, resulting in expansion. The combustion causes the piston to lower, which turns the crank and generates enough power for driving the vehicle. This is the power stroke.

When the vehicle engine is powered, the exhaust valve opens, releasing the combination of air and petrol as the piston hits the cylinder bottom. The piston heads back up again, releasing burnt fuels via the exhaust valve in the final stroke – exhaust.

Contact the crankshaft experts in Durban

Whether you’re looking for trusted pre-owned crankshafts or our crankshaft maintenance service, Eagleharm Engineering is your trusted source for quality engine parts. We have over 50 years of experience in the vehicle engineering field.

Contact us today to find out more about what we offer and get expert advice on how a crankshaft works in an engine.

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