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The question is asked for various proportions : - 10% of petrol - 50% of petrol - 100% of petrol in a diesel engine.
PS : not a duplicate of What happens if unsuitable oil is used in a vehicle engine? !
If you mention a possible damage, please specify the technical reasons with it.
EDIT : didn't know the petrol equivalent in English. Thanks for the suggestions to edit.
The key differences between petrol and diesel engines is the method of combustion.
Petrol ignites with sparks or with compression. Diesel doesn't ignite so well, but burns much better through compression.
Petrol engines inject the air/fuel mixture and then use spark plugs to ignite the mixture just after a piston reaches top dead centre.
Diesel engines compress air, and then add air/fuel mixture. As a result they run hotter. The compression and heat give combustion, rather than flash ignition.
The differences between the fuels are measured on the octane or cetane rating. Fuels with a high octane have a low cetane and are easy to ignite, so work well in petrol engines. Fuels with low octane and high cetane ignite by combustion so work well in diesel engines.
I've heard that a very small amount of petrol (0.5L in a full tank) can actually improve the efficiency of a car, but this must be treated as a rumour. Engine damage could still occur.
10% petrol will result in "knocking" or "pinking", where the engine runs very rough. This is because the petrol will ignite prematurely in the diesel engine, and there will be a loss of power as the combustion happens over a longer time than with 100% diesel. Some damage may also occur to the fuel supply system as petrol is less lubricative than diesel, and strips out some of the lubrication needed for diesel pumps to work well. Example: http://www.youtube.com/watch?v=CvjrT5mRj_U
50% petrol will result in engine damage, as the incorrect timing of combustions will put high stresses on engine components. Something like this would happen:
http://www.youtube.com/watch?v=MuW7biMuslI
http://www.youtube.com/watch?v=Fw2r_lIRgpY
100% petrol will also kill the engine. Think along the lines of these:
http://www.youtube.com/watch?v=Hxe61AQI0ek
http://www.youtube.com/watch?v=LpJtRZl0uC4
Other references
Other than damaging or ruining the fuel injection pump due to lack of lubrication from gasoline, the engine will be much harder or impossible to start because gasoline needs even higher compression than diesel to create enough heat to ignite the fuel. Once it is running it will actually run fine until the fuel pump is damaged and it may even have more power since gasoline burns faster than fuel oil, causing more of the fuel to burn while the piston is at the top of the cylinder.
If we use petrol in disel engine then due to its low compression ratio,it will burn before piston reach tdc- hence causing detonation & vibration. Thus engine will work unevenly for sometime & then stop after engine damage. Another point to note is that petrol is volatile so it will be difficult for injectors to spray it like diesel,, it will immediately mixup & thus the phenomena of rapid /instant burning at tdc point won't be there..petrol mix is suitably ready so it will burn much earlier than expected point..so again we can see that engine will run but will stop after cracking engine or crank!
THANKS FOR SO MUCH LIKES!
