If you get confused at the gas pump on which fuel to use, then we are here to help. This video breaks down the differences between petrol, or gasoline, and diesel engines.
Petrol and diesel engines both operate on a four-stroke cycle:
- Suction Stroke – The piston goes down and sucks air into the cylinder and fuel is injected.
- Compression Stroke – The piston drives up, rapidly compressing and heating the air and fuel that just were sucked into the cylinder.
- Power Stroke – A spark plug ignites the hot air and fuel to press the piston back down the cylinder. This is what powers the engine.
- Exhaust Stroke – Finally, the used up air and fuel are let out of the exhaust port as the piston drives up. The cycle begins again.
Gasoline and diesel engines differ in how they ignite the fuel in the cylinder. A diesel engine does not need a spark plug to ignite the compressed air and fuel. Instead, it relies on compressing the air and fuel to a self-ignition temperature.
This is the essential difference between petrol and diesel engines. To learn more about the differences, watch the video in the link above.