Four-stroke engine
A four-stroke engine turns many small bursts of burning fuel into a turning shaft. It drives most cars, motorbikes and lawnmowers.
Here you don't just read about it. You run a cut-open petrol engine in 3D: start it, turn the crank by hand, open the throttle, and watch the valves, the spark and the pressure inside the cylinder. Pick a question below for a guided tour, or explore the engine freely.
What do you want to find out?
How does a four-stroke engine work?
Follow one cylinder through intake, compression, power and exhaust, and find out why it takes four strokes.
9 steps · Beginner
What does a throttle do?
Open the throttle and see what changes: how much air gets in, the pressure in the cylinder, and the engine speed.
6 steps · Beginner
How this was made
This simulation was built with AI from the sources below. Before it goes online, an automated test checks every control, view and part. It is a simplified model: the numbers are realistic, but they are not those of one specific engine, and it may contain errors. If you find one, write to us: office@soticek.com