The Diesel engine

• Operates in almost the same way as the Petrol Engine apart from certain differences:
• They use diesel instead of Petrol
• Have no spark plugs
• Have a fuel injector instead of a carburettor
• Diesel engines are also known as compression-ignition engines
• They are heavier than Petrol engines because they have to withstand the pressure

How they work?

The diesel engine. Image credit blogspot.com

• Air is drawn into the cylinder during the down-stroke movement of the piston
• Air is compressed when the piston moves up
• The compression of diesel engines is about twice as strong as that of Petrol engines
• The compressed air becomes very hot due to this compression
• Fuel is now pumped into the cylinder by the fuel injector
• Because of the high temperature of the compressed air in the cylinder
• the fuel  ignites
• The resultant explosion pushes the piston down on its power stroke
• Diesel engines are bulkier than Petrol engines so as to be able to withstand the extra pressure
• They are however more efficient than Petrol Engines

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