The four stroke diesel engine animation

1. Suction stroke: Pure air gets sucked in by the piston sliding downward.

2. Compression stroke: The piston compresses the air above and uses therby work, performed by the crankshaft.



3. Power stroke: In the upper dead-center, the air is max. compressed: Pressure and Temperature are very high. Now the black injection pump injects heavy fuel in the hot air. By the high temperature the fuel gets ignited immediately (autoignition). The piston gets pressed downward and performes work to the crankshaft.

4. Expulsion stroke: The burned exhaust gases are ejected out of the cylinder through a second valve by the piston sliding upward again.