Diesel Engine

The only difference between diesel engine and a four-strokegasoline engine is:•No sparkplug on Diesel engine.•Has a higher compression ratio. (14:1 to 25:1)•Better fuel mileage.

Diesel Engine

Intake Stroke:

•Piston moves from TDC to BDC creating vacuum in the cylinder

•Intake valve opens allowing only air to enter the cylinder and exhaust valve remains closed

Diesel EngineCompression Stroke

•Both valves stay closed

•Piston moves from BDC to TDC, compressing air to 22:1

•Compressing the air to this extent increases the temperature inside the cylinder to above 1000 degree F.

Diesel EnginePower Stroke

•Both valves stay closed

•When the piston is at the end of compression stroke(TDC) the injector sprays a mist of diesel fuel into the cylinder.

•When hot air mixes with diesel fuel an explosion takes place in the cylinder.

•Expanding gases push the piston from TDC to BDC

Diesel EngineExhaust Stroke

•Piston moves from BDC to TDC

•Exhaust valve opens and the exhaust gases escape

•Intake valve remains closed

Diesel EngineFour Strokes of Diesel Engine