Gasoline Engine Cycle Work

Common car usually have 4 cycle, especially for gasoline engine,  for diesel engine may have higher cycles because they need high power.

Cycle work of gasoline engine can describe as follows:

1. Sucking Cycle

• Inlet valve opened, piston move downward and suck mixture of fuel and air into the cylinder. If the cylinder is in the lowest position, all the cylinder room will full of the mixture, and this cycle end.

2. Compression Cycle

• Inlet valve closed, piston move upward and will compress the cylinder contains (mixture of fuel and air), and before the piston reach the top position, ignition then merge from spark plug.

3. Work Cycle

• The mixture of fuel then fired arise eruption and push the piston downward and before reach the lowest position, exhaust valve then opened.

4. Exhaust Cycle

• Piston then moves upward and pushes the burnt gas mixture out of cylinder. All the process then repeat from the beginning.

This all cycle called as engine 4 cycles. Piston volume represent as V1 letter, this volume is a mixture volume that suck into the cylinder when the piston on the lowest position. The other volume is when the piston on the top position, and this volume represented as V2, this space is called as combustion volume.

The comparison of V1/V2 is called as compression ratio. For gasoline engine this ratio value is 7 to 9, and for diesel engine this ratio value is 12 to 20.

Where:
V1 : Combustion volume (Vc)
V2 : Piston cycle volume (Vp)