1. Diesel Engines TRF 210

2. History of Diesel Engines 1890 Dr Rudolf Diesel had a theory that any fuel could be ignited by the heat caused by high pressure No spark plug or electric ignition system Early Diesel engines were big and less powerful than spark ignition engines of the time

3. History of Diesel Engines cont. 1920 Robert Bosch developed a new type of mechanical fuel-injection system Cars, locomotives, and ocean liners Today new smaller light weight engines for use in small lawn and garden tractors and other types of small equipment

4. Diesel Engine Construction Mechanically similar to spark-ignition engines Diesel engines parts are heaver due to greater pressures in the cylinder during combustion Piston strokes occur in the same sequence

5. Difference between Diesel and Spark-Ignition Engines Diesel engines can be 2 or 4 stroke engines most are 4 stroke How the fuel is introduced into the cylinder How the resulting air fuel mixture is ignited

6. The Diesel Cycle Intake: only air enters the cylinder (intake valve open) Compression: air is compressed as piston moves up (intake and exhaust closed) Power: diesel fuel is injected as piston nears TDC (heat of compression ignites fuel) the resulting explosion pushes piston down (constant pressure combustion) Exhaust: piston moves up and pushes burned gasses out (intake valve closed exhaust open)

8. Heat of Compression 16-1 ratio creates 500psi Increases temperature 2 degrees per psi All diesel engines are compression ignition engines All diesel engines are over head valve engines

9. Pressure, temperature, and volume relationship in a cylinder.

11. Diesel Fuel Light oil that helps to lubricate engine Must burn cleanly producing little ash

12. More Diesel Stuff Fuel Injection pump Injection nozzles Glow plugs Pre-combustion chambers