eLearning | Computer Based Training | Systems Simulation
A 2-stroke engine is an internal combustion engine (ICE) that burns a mixture of air, petrol and oil to drive a piston and rotate a crankshaft.
Unlike a 4-stroke engine, a 2-stroke engine fires on every revolution of the crankshaft and performs all the functions of a 4-stroke engine (induction, compression, combustion and exhaust) using only a combustion and a compression stroke.
A 2-stroke engine fires on every revolution of the crankshaft and performs all the functions of a 4-stroke engine using only 2 strokes (a combustion and a compression stroke).
It does this by inducting the fuel mixture into the crankcase towards the end of the compression (upward) stroke and releasing the exhaust gases towards the end of the combustion (downward) stroke.
A transfer port allows the fuel mixture in the crankcase to escape around to the top of the piston where it purges the main cylinder of exhaust gases before being finally compressed by the upward moving piston.
You can use the controls on the interactive animation to clearly view the working cycle of a 2-stroke engine:
Press to play or pause the animation.
Press to step through the animation one frame at a time!