Diesel Engine Noise

April 1, 2014

Noise from Diesel Engines

Have you ever wondered why diesel engines make that distinctive “diesel” noise while running? You know this noise.

Before I began my career as a diesel technician I always wondered why as well. It took me many years, and many grease stains to figure it out.

To really understand the answer to this question, we have to first understand the difference between a gasoline and diesel engine.

  • Gasoline engines use spark plugs to ignite an air/fuel mixture, causing the car to turn over and start – Imagine throwing a lit match in a cup of gasoline.
  • Diesel engines use super-hot compressed air to ignite fuel. When the fuel mixes with the compressed air, the fuel is immediately vaporized. The vaporization causes a delay; this delay is basically a small controlled explosion due to pressure. This explosion from the diesel fuel firing is what causes the distinct diesel sound that I love ooh so much.

So if you’re interested in understanding more than why the diesel engine rattles. Stop by and check out Oklahoma Technical College and you can hear more about engines and what makes them tick.

More on Diesel Technology: