I have a diesel engine running. And I switched the diesel fuel to gasoline fuel. It does not ignite at all. Why ?


Diesel and petrol/gasoline are totally different fuels, and work in different ways.

Diesel engines are known as 'compression ignition' - Diesel fuel is heavy and has low volatility (meaning that it doesn't burn well), and in a Diesel engine is it injected into a cylinder full of compressed air at a high pressure and temperature, which causes the fuel to ignite.

In a petrol engine on the other hand, the fuel is much thinner, lighter and more volatile, and is ignited by means of a spark - these engines run at much lower pressure.

The two are not compatible, and neither fuel will work in an engine designed for the other.

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Diesel is compression ignition and the gasoline engine is spark ignition..

So you need to provide a spark to ignite the gasoline.

However, in some situations you can get run away of diesel engines where uncontrolled fuel or oil is causing the engine to continue running - these can actually over- rev and fail.

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