A four stroke engine operates in a cycle of intake, compression, power, and exhaust strokes. The intake stroke draws fuel and air into the cylinder with the piston moving down. In the compression stroke, both valves close and the piston compresses the fuel-air mixture. The power stroke ignites the compressed mixture to push the piston down. Finally, in the exhaust stroke the piston pushes gases out through the open exhaust valve as it returns to the top.

1. FOUR SRTOKE CYCLE
ENGINE
IS AN INTERNAL COMBUSTION ENGINE

2. FOUR STROKE CYCLE
•Intake
•Compression
•Power
•Exhaust

3. Intake
this stroke of the piston begins at
top dead center.

4. Compression
• with both intake and exhaust
valves closed

5. Power
this is the start of the
second revolution of the
cycle

6. Exhaust
• …the piston once again
returns to top dead centre
while the exhaust valve is
open.

7. Four cycle

8. THANKS!!