@jaspal rautela • 08 Jun, 2012
I am a Mechanical Engineer from Dehradun and I've a query regarding petrol and diesel engines. I want to know why we can't use petrol in diesel engine? What are the changes in technology used that prevent us from doing it?
@Gurjap • 08 Jun, 2012 Diesel Engines use compression-ignition technology to burn fuel. That means the fuel is compressed till it burns. That requires a certain kind of fuel, which doesn't burn irregularly when subjected to compression. Petrol does not fall in this category. Hence it isn't used in diesel engines.

That being said, Homogeneous Charge Compression Ignition (HCCI) engines can burn petrol.
@Ayush_pse • 08 Jun, 2012 so if we fill a diesel tank with petrol or vice versa, the vehicle wont run at all?
@Gurjap • 09 Jun, 2012 • 3 likes If you fill a diesel with petrol, the vehicle will run, but very badly, with coughing and chugging. This is because the petrol will ignite very unpredictably if you compression-ignite it. If you put diesel in a petrol, though, it won't run at all, or will run for a short time with very smoky exhaust. This is because diesel is much heavier and much less volatile than petrol is, and it may not even reach its flash point in the SI engine. In any case, diesel requires heavy-duty pumps to atomize it before it can be burned. The fuel injectors in SI engines aren't designed for that job.
@jaspal rautela • 09 Jun, 2012 in CI engine what is compresse either fuel or air?
@Ayush_pse • 10 Jun, 2012 air.
@jaspal rautela • 10 Jun, 2012 bv gurjap said that fuel is compressd..
@jaspal rautela • 10 Jun, 2012 but gurjap said that fuel is compressd..
@saravanan4 • 10 Jun, 2012 • 1 like Diesel engine will compress air and fuel injector will spray the fuel and the mixture will get ignited due to compression, where there will be no need of spark plug in diesel engine , the compression will be itself help in ignition
ONLY petrol engine will compress the air fuel mixture, because this mixture is prepared in carburetor and hence the mixture will get ignited by a spark plug through a spark from the battery.
now a days MPFI has come and replaced the carburetor.
@jaspal rautela • 10 Jun, 2012 what is difference between MPFS, and carburator?
@Gurjap • 11 Jun, 2012 I did say that fuel is compressed, but I was trying to simplify. Certainly air is compressed, and then the fuel is sprayed into the diesel engine.
@The myth buster • 25 Jun, 2012 It's a very simple concept.A diesel or compression ignition engine works on the principle of autoignition of the fuel-air mixture.A petrol engine on the other hand,Rely on a spark plug to initiate the combustion process.Gasoline has high auto-ignition temperature whereas diesel has low auto-ignition temperature value.Thus gasoline wouldn't undergo complete combustion in a diesel engine and would lead to excessive knocking and would ultimately cause engine damage..!!
@dhananjay pathak • 26 Jun, 2012
saravanan4
Diesel engine will compress air and fuel injector will spray the fuel and the mixture will get ignited due to compression, where there will be no need of spark plug in diesel engine , the compression will be itself help in ignition
ONLY petrol engine will compress the air fuel mixture, because this mixture is prepared in carburetor and hence the mixture will get ignited by a spark plug through a spark from the battery.
now a days MPFI has come and replaced the carburetor.
u said that the ignition occur due to compression,i think ,if we go more deep ,the compressed air gets heated due to compression and at that time if we apply fuel on that compressed air (heated) then only the combustion occurs and it pushes the piston . am i right ? if not pls correct...
@dhananjay pathak • 26 Jun, 2012
The myth buster
It's a very simple concept.A diesel or compression ignition engine works on the principle of autoignition of the fuel-air mixture.A petrol engine on the other hand,Rely on a spark plug to initiate the combustion process.Gasoline has high auto-ignition temperature whereas diesel has low auto-ignition temperature value.Thus gasoline wouldn't undergo complete combustion in a diesel engine and would lead to excessive knocking and would ultimately cause engine damage..!!
what is knocking?
@The myth buster • 26 Jun, 2012 • 1 like well in petrol engines,it may be possible that some amount of air-fuel mixture attain its autoignition temperature and undergo preignition.This preignition would then set up a new flamefront that would travel in opp direction to the flame setup as a result of the spark,produced by the spark plug.this causes the waves to undergo interference and thus this sets up a huge pressure differential.This causes engine vibrations and which ultimately leads to engine parts damage.This whole phenomenon is called as knocking.
@dhananjay pathak • 26 Jun, 2012
The myth buster
well in petrol engines,it may be possible that some amount of air-fuel mixture attain its autoignition temperature and undergo preignition.This preignition would then set up a new flamefront that would travel in opp direction to the flame setup as a result of the spark,produced by the spark plug.this causes the waves to undergo interference and thus this sets up a huge pressure differential.This causes engine vibrations and which ultimately leads to engine parts damage.This whole phenomenon is called as knocking.
thanks,but i understood partially, can u pls illustrate more easy way?
@The myth buster • 27 Jun, 2012 https://auto.howstuffworks.com/fuel-efficiency/fuel-consumption/question90.htm
dhananjay pathak
thanks,but i understood partially, can u pls illustrate more easy way?
@dhananjay pathak • 27 Jun, 2012
The myth buster
https://auto.howstuffworks.com/fuel-efficiency/fuel-consumption/question90.htm
ok thank u the link helped me lot , so there is no ques of knocking for diesel engines right? it occures only in gasolene engines
@vikaskumar11233 • 27 Jun, 2012 If we fill a petrol engine with kerosene then what will happen?
@The myth buster • 27 Jun, 2012
dhananjay pathak
ok thank u the link helped me lot , so there is no ques of knocking for diesel engines right? it occures only in gasolene engines
actually what causes knocking in petrol engines is a requirement in diesel engines..i.e autoignition..but diesel engines also knock.This phenomenon is called as "Diesel knock" but the reasons for it are different..!!
@nibhani • 28 Jun, 2012 petol has high self ignition temprature so sparking is necessary for ignition and in diesel engine spark plug is not available so we can't use it in diesel engine and also petrol is not much energetic than diesel so for heavy vehicle we use diesel and petrol can't be used in heavy vehicles...
@ISHAN TOPRE • 28 Jun, 2012 I think, Bajaj is planning to launch such bikes. Final year engineering students from Punjab modified their bike and are thinking to launch it in market with the help of big companies. Search Google and you will find it. I have less time hence cannot search post the link.

But here is something-https://www.rediff.com/getahead/slid...-soon-to-india-diesel-superbikes/20120606.htm
@piyusheddie • 28 Jun, 2012 JASPAL, If m not wrong den u must me takin bout the difference between MPFI system & a Carburetor....
@piyusheddie • 28 Jun, 2012 • 1 like JASPAL,

Well MPFI stands for Multi Point Fuel Injection system. In this system every cylinder of engine is equiped with separate fuel injector (sometime two), which is use to supply the fuel separately to combustion chamber of cylinder and air is being sucked in traditional way thru valves. The injector rapidly transform the liquid fuel into the gaseous mist so that it can mixed with incoming air suddenly at the time of intake stroke. The amount of fuel need to be injected into the combustion chamber is controlled by a microprocessor based systems which helps in improving fuel efficiency & performance.

Whereas Carburetor is used to blend the liquid fuel with air outside the combustion chamber unlike the way it use to be in MPFI system. In order to achieve the stichiometric ration of fuel with air the carburetor has to be tuned manually as there isnt any microprocessor to do the mixing job. Obviously the fuel efficiency & performance of carburetor engine is bit low as compare to mpfi engine.

I hope this will help u......😀
@piyusheddie • 28 Jun, 2012
dhananjay pathak
u said that the ignition occur due to compression,i think ,if we go more deep ,the compressed air gets heated due to compression and at that time if we apply fuel on that compressed air (heated) then only the combustion occurs and it pushes the piston . am i right ? if not pls correct...
YES DUDE U R ON RIGHT SIDE......😀
@piyusheddie • 28 Jun, 2012
The myth buster
https://auto.howstuffworks.com/fuel-efficiency/fuel-consumption/question90.htm

Dude,

to understand the concept of Knocking fully, I suggest u to consult the books
1. AUTOMOTIVE MECHANICS by Cruse n Anglin "Tata Macgrawhill"
2. AUTOMOBILE ENGINEERING by R. B Asthana & R.B Gupta

hope this will help u.....😀
@dhananjay pathak • 29 Jun, 2012
piyusheddie
YES DUDE U R ON RIGHT SIDE......😀
thanx dude
@dhananjay pathak • 29 Jun, 2012
nibhani
petol has high self ignition temprature so sparking is necessary for ignition and in diesel engine spark plug is not available so we can't use it in diesel engine and also petrol is not much energetic than diesel so for heavy vehicle we use diesel and petrol can't be used in heavy vehicles...
so, what you will say about usage of kerosene in the S.I engine?
@piyusheddie • 30 Jun, 2012
dhananjay pathak
so, what you will say about usage of kerosene in the S.I engine?

dude, auto ignition temp for kerosene is almost 295 deg C approx. n its obviously higher than petrol ( 246 deg C approx). Moreover there r lots of others factors which may restrict the use of kerosene oil in S.I engines like : low flameability , high ignition temp, low flame speed, burning of kerosene takes lot more time than petrol it means not suitable for rapid combustion, kerosene takes long time to get vaporized as compare to petrol etc......
@dhananjay pathak • 30 Jun, 2012 • 1 like
piyusheddie
dude, auto ignition temp for kerosene is almost 295 deg C approx. n its obviously higher than petrol ( 246 deg C approx). Moreover there r lots of others factors which may restrict the use of kerosene oil in S.I engines like : low flameability , high ignition temp, low flame speed, burning of kerosene takes lot more time than petrol it means not suitable for rapid combustion, kerosene takes long time to get vaporized as compare to petrol etc......
thanx dude
@SYED BASEERULLAH • 01 Jul, 2012 i know about mpfi but not about this MPFS

The carburetor, carburettor, or carburetter (see spelling differences), also called carb (in North America) or carbie (chiefly in Australia) for short, is a device that blends air and fuel for an internal combustion engine. It was invented by Hungarian scientists Donát Bánki and János Csonka in 1893. Carburetors are still found in small engines and in older or specialized automobiles such as those designed for stock car racing. However, fuel injection, first introduced in the late 1950s and first successfully commercialized in the early 1970s, is now the preferred method of automotive fuel delivery. The majority of motorcycles still are carbureted due to lower cost but as of 2005 many new models are now being introduced with fuel injection.

Most carbureted (as opposed to fuel-injected) engines have a single carburetor, though some engines use multiple carburetors. Older engines used updraft carburetors, where the air enters from below the carburetor and exits through the top. This had the advantage of never "flooding" the engine, as any liquid fuel droplets would fall out of the carburetor instead of into the intake manifold; it also lent itself to use of an oil bath air cleaner, where a pool of oil below a mesh element below the carburetor is sucked up into the mesh and the air is drawn through the oil covered mesh; this was an effective system in a time when paper air filters did not exist. Beginning in the late 1930s, downdraft carburetors were the most popular type for automotive use in the United States. In Europe, the sidedraft carburettors replaced downdraft as free space in the engine bay decreased and the use of the SU-type carburetor (and similar units from other manufacturers) increased. Some small propeller-driven aircraft engines still use the updraft carburetor design, however many use more modern designs such as the Constant Velocity (CV) Bing(TM) carburetor.

The carburetor works on Bernoulli's principle: the faster air moves, the lower its pressure. The throttle (accelerator) linkage does not directly control the flow of liquid fuel. Instead, it actuates carburettor mechanisms which meter the flow of air being sucked into the engine. The speed of this flow, and therefore its pressure, determines the amount of fuel drawn into the airstream.

M.P.F.I. means Multi Point Fuel Injection system. In this system each cylinder has number of injectors to supply/spray fuel in the cylinders as compared to one injector located centrally to supply/spray fuel in case of single point injection system.

Advantage of M. P. F. I.

(1) More uniform A/F mixture will be supplied to each cylinder, hence the difference in power developed in each cylinder is minimum. Vibration from the engine equipped with this system is less, due to this the life of engine components is improved.

(2) No need to crank the engine twice or thrice in case of cold starting as happens in the carburetor system.

(3) Immediate response, in case of sudden acceleration / deceleration.

(4) Since the engine is controlled by ECM* (Engine Control Module), more accurate amount of A/F mixture will be supplied and as a result complete combustion will take place. This leads to effective utilization of fuel supplied and hence low emission level.

(5) The mileage of the vehicle will be improved.
@SYED BASEERULLAH • 01 Jul, 2012 under steady through net i found this above answer efficient enough to know about this 2 components
@sweet_honey • 26 Jul, 2012 MPFS injects the fuel to the cylinder thru many points in diffrent cylinders but carburator prepares a mixture of air and fuel and sends it to the combustion chamber
@Ankita Katdare • 29 Jan, 2014 Just a newbie question -

What would happen if you actually put petrol in a diesel engine?
Will there be damage to the car's performance?
@ISHAN TOPRE • 30 Jan, 2014 I will cause knocking. Petrol will not burn properly and the the engine performance will suffer drastically. Everything is written in detail in earlier posts by other members.
@autoaddict • 22 May, 2014 then why can we use a ignition system in diesel engines......?do they lead to higher efficiency??
@spiceluvver • 30 May, 2014 • 1 like
autoaddict
then why can we use a ignition system in diesel engines......?do they lead to higher efficiency??
diesel engines are 2 stroke engine and petrol engines are 4 stroke engine.
Therefore the power produced by diesel engines is more than that of petrol engines,
since the diesel engines don't require external help for burning the fuel, they don't need a separate ignition system.
@spiceluvver • 30 May, 2014
nibhani
petol has high self ignition temprature so sparking is necessary for ignition and in diesel engine spark plug is not available so we can't use it in diesel engine and also petrol is not much energetic than diesel so for heavy vehicle we use diesel and petrol can't be used in heavy vehicles...
i would rather say because diesel engines are 2 stroke engines and petrol engines are 4 stroke, and the power produced by 2 stroke engines is more than that of 4 stroke, hence we use diesel engines for heavy vehicals
@ashish_mittal • 07 Sep, 2014
Gurjap
I did say that fuel is compressed, but I was trying to simplify. Certainly air is compressed, and then the fuel is sprayed into the diesel engine.
just tell me if first air is compressed and then fuel is sprayed then y not petrol will ignite homogeneously as compression raised temp of petrol to 500 degree and petrol ignition temperature is 280
@Shashank Moghe • 08 Sep, 2014 The real answer lies in the methods of combustion of both fuels: Petrol and Diesel.
- Petrol combustion is dependent on flame kernel development and subsequent flame front propagation. This (the kernel) is accomplished with the help of a spark in the SI engine.
- Diesel can combust upon compression. But petrol needs a spark to initiate combustion.There is no flame kernel and hence no flame front in Diesel combustion. Combustion occurs at all locations upon achievement of the necessary temperature.
This is an excellent question, although a "diesel in petrol engine" question would be easier to answer. Any rightful corrections are welcome.
@Shashank Moghe • 09 Sep, 2014 Also, I would like to retract my statement claiming Petrol cannot burn in a diesel engine. Although petrol has a higher Auto-Ignition temperature than diesel, at the diesel engine compression ratios, enough high temperatures are reached to cause petrol to auto-ignite. The only problem is that since the petrol is more volatile than diesel, it burns very spontaneously as compared to diesel (when allowed to auto-ignite). And also much hotter.

Now, this spontaneous combustion is obviously uncontrollable ("knocking") and causes severe structural damage to the engine. Besides, the NOx emissions are increased since it has a higher maximum combustion temperature.

Controlling combustion over several crank angle degrees is the prime motive in extracting power out of an engine. Hence knocking is undesirable (besides the obvious reason that knocking damages the engine).
@Sarathkumar Chandrasekaran • 09 Sep, 2014
shashank Moghe
Also, I would like to retract my statement claiming Petrol cannot burn in a diesel engine. Although petrol has a higher Auto-Ignition temperature than diesel, at the diesel engine compression ratios, enough high temperatures are reached to cause petrol to auto-ignite. The only problem is that since the petrol is more volatile than diesel, it burns very spontaneously as compared to diesel (when allowed to auto-ignite). And also much hotter.

Now, this spontaneous combustion is obviously uncontrollable ("knocking") and causes severe structural damage to the engine. Besides, the NOx emissions are increased since it has a higher maximum combustion temperature.

Controlling combustion over several crank angle degrees is the prime motive in extracting power out of an engine. Hence knocking is undesirable (besides the obvious reason that knocking damages the engine).
could you please explain more on flame kernel because during my Automobile engineering, i have been taught only about flame propogation in detail and not about kernel.
@Shashank Moghe • 09 Sep, 2014
SarathKumar Chandrasekaran
could you please explain more on flame kernel because during my Automobile engineering, i have been taught only about flame propogation in detail and not about kernel.
A kernel literally means the core. You can visualize that to be the birthplace of a flame in the combustion chamber. When a voltage greater than the breakdown voltage (this is directly proportional to the electrode gap) is applied between the electrodes, the air-fuel mix is transformed to the plasma state and the electrons travel in the space creating the discharge. The kernel development has three stages (if I have not forgotten the basics) and ultimately you can imagine a sphere of small dimension that expands in the chamber with its surface acting as the place where chemical reactions (or combustion) happen. This surface is called the flame front.

This explanation is crude, but sometimes I have problems remembering the exact specific details. If you are really interested, you can refer John Heywood. It is the bible of IC Engines.
@Sarathkumar Chandrasekaran • 10 Sep, 2014
shashank Moghe
A kernel literally means the core. You can visualize that to be the birthplace of a flame in the combustion chamber. When a voltage greater than the breakdown voltage (this is directly proportional to the electrode gap) is applied between the electrodes, the air-fuel mix is transformed to the plasma state and the electrons travel in the space creating the discharge. The kernel development has three stages (if I have not forgotten the basics) and ultimately you can imagine a sphere of small dimension that expands in the chamber with its surface acting as the place where chemical reactions (or combustion) happen. This surface is called the flame front.

This explanation is crude, but sometimes I have problems remembering the exact specific details. If you are really interested, you can refer John Heywood. It is the bible of IC Engines.
thanks a lot. i will search for it?!!
@uu99 • 08 Jun, 2015 The problem is volatility of diesel is very less than the petrol, it will not vaporise easily. Thus no mixture of diesel and air is possible. As a result the diesel will not ignite with spark and engine won’t start

www.automechansys.in or
www.facebook.com/automechansys
@Shashank Moghe • 08 Jun, 2015
uu99
The problem is volatility of diesel is very less than the petrol, it will not vaporise easily. Thus no mixture of diesel and air is possible. As a result the diesel will not ignite with spark and engine won’t start

www.automechansys.in or
www.facebook.com/automechansys
Diesel is direct injected, at extremely high pressures, hence the injection pressure and the nozzle diameter will basically take care of the atomization and eventual vaporization. There is more to the reason why diesel cannot be used in a petrol engine, than this.
@msuresh444 • 09 Jun, 2015 • 1 like
jaspal rautela
I am a Mechanical Engineer from Dehradun and I've a query regarding petrol and diesel engines. I want to know why we can't use petrol in diesel engine? What are the changes in technology used that prevent us from doing it?
Firing in diesel engines is thru compression ignition. If you pour petrol in a diesel engine and crank, it wont ignite, reason being petrol needs a very high pressure to self-ignite. Some diesel engines use glow-plugs to pre-heat the combustion chambers for quick start of engines (during winters).
Altering a diesel engine to run on petrol would not be a good idea! You have to reduce the weight of all engine components/materials, etc.
@Shashank Moghe • 09 Jun, 2015 • 2 likes
msuresh444
If you pour petrol in a diesel engine and crank, it wont ignite, reason being petrol needs a very high pressure to self-ignite
Nope. The Compression Ratio of a CI engine is much higher than that for an SI engine. The autoignition temperature for Petrol is 280 C while that for Diesel is 400 C. Petrol will combust much before the TDC causing an opposite push to the inertial motion of the piston assembly- structurally dangerous.

msuresh444
Altering a diesel engine to run on petrol would not be a good idea! You have to reduce the weight of all engine components/materials, etc.
Weight of all the CI engine components is the result of the increased Compression Ratio and the high torque output of Diesel. It is not the cause.
@msuresh444 • 09 Jun, 2015
Shashank Moghe
Nope. The Compression Ratio of a CI engine is much higher than that for an SI engine. The autoignition temperature for Petrol is 280 C while that for Diesel is 400 C. Petrol will combust much before the TDC causing an opposite push to the inertial motion of the piston assembly- structurally dangerous.


Weight of all the CI engine components is the result of the increased Compression Ratio and the high torque output of Diesel. It is not the cause.
Right!
Apologies...was in a bad mood yesterday while typing! 😛 its the inverse of what I wrote...
@msec123 • 10 Jun, 2015 We can't use petrol in diesel engine, It is a volatile fuel and highly combustible. Petrol requires less temperature to ignite as compared to diesel. Therefore petrol engines have low compression ratio and less piston rings. If we use petrol in diesel engine it will ignite before injecting into in the cylinder. Also due to volatility injectors will not be able to inject fuel vapors with that pressure at which they inject diesel in the cylinder.
Also petrol does not provide lubrication as diesel provides to plunger, nozzles and other moving parts inside the fuel injection system. So petrol will damage fuel injection system.
@Shashank Moghe • 10 Jun, 2015
msec123
Therefore petrol engines have low compression ratio and less piston rings.
Nope, petrol and diesels these days have the same number of rings. Petrol engines are also DI these days. In fact, the first ring groove comes with an insert (which protects the groove against the high combustion pressures), a design that was very common in Diesel engines before DI in petrol was commonplace.

msec123
If we use petrol in diesel engine it will ignite before injecting into in the cylinder.
What? How is that possible?

msec123
Also due to volatility injectors will not be able to inject fuel vapors with that pressure at which they inject diesel in the cylinder.
What does "inject vapors" even mean?

msec123
Also petrol does not provide lubrication as diesel provides to plunger, nozzles and other moving parts inside the fuel injection system. So petrol will damage fuel injection system.
What???? Plunger? Nozzle is a moving part that needs lubrication?
You are only partially right in saying that petrol will damage the fuel injection system, but the fact is that modern Diesel injection systems will not allow petrol to pass through even if you accidentally filled it with petrol (this part is something I read on the internet).
@msajce • 12 Jun, 2015 If we put diesel in petrol engine, then either it will not run at all or run for a short distance with much smoky exhaust. Diesel is less volatile and much heavier then petrol, hence it will not be able to reach its flash point.
Diesel engine is compression ignition type that works on the principle of spraying atomized system into the internal chamber. In diesel engine air temperature, at a time may reach up to 600 degree. In this temperature, using petrol instead of diesel may cause explosion. Gasoline or petrol is more flammable than diesel, hence in this temperature it will ignite vastly and create excess of temperature that will either break the piston or may be more terrible.
@Ankita Katdare • 21 Jun, 2015 What should one do we if he puts petrol in diesel engine or vice versa?
Is it best to not start the ignition and have it drawn out immediately?
If you realize it too late, what harm can it cause to the vehicle?
@Shashank Moghe • 22 Jun, 2015 • 1 like Diesel in petrol engine wont burn because of the insufficient compression ratio, while the reverse is not true and can lead to uncontrolled sudden combustion of petrol in the diesel engine. It is best to drain the tank from a professional in either cases. Petrol in a diesel can cause structural and fuel pump system damage. Diesel in petrol will be noticeable immediately when the vehicle wont run at all, not causing any structural problems as I see it, unless you drain just the tank out of diesel and refill it with petrol and restart ignition- in which case there would be a little diesel in the fuel line, the combustion chamber and the exhaust line [this part is hypothesis]. Hence at the combustion temperatures and pressures of petrol, Diesel will also auto-ignite, which can cause increased combustion pressures/temperatures. One obvious effect will be higher NOx emissions, but may also possibly cause structural component damage due to higher-than designed thermal loads.

This brings me to a very novel idea (might also be very stupid). How about initiating combustion with petrol and then injecting diesel when the pressure + temperature is ripe for diesel auto-ignition? Thanks @Ankita Katdare ! Let me start a new thread!
@Kamlesh Vora • 13 Aug, 2015 • 1 like Okay let me try to explain this as per my best.
Diesel and Petrol has different properties. The basic one is vaporization, Petrol will vaporized in Room Temperature, whereas Diesel will take time. but Both need 300 c temp.(approx.) to ignite.
now 2 reasons why u cant use Petrol in Diesel vehicle.
1st their design: They are designed differently as I said Petrol gets vapories easily, so Petrol Engine has Carburation system in which vapour of petrol mixes with air in to venturi of carburetor and then goes into as complete mixture in to cylinder. Where ignition takes place when spark plug fires heavy voltage ( 100 cc bike engine spark plug can produce 20k Volts) which burns nearby petrol vapor molecules and creates a series of fire inside cylinder which lets u POWER STROKE.
Whereas Deisel cannot vaporized easily so fresh air is been suck by cylinder and when the cylinder closes the piston compressed the simple air inside. Now during compression of the Air which is squeezed in swept volume it increases the temperature and on that Hot Pressurised air Diesel is spray on it. during the spray diesel gets divided into tiny molecules form which cached heat and fires inside.

2nd reason is a difference of Compression ratio, Petrol engines have compression ratio of 1:6 to 1:12 whereas diesel engines have 1:18 to 1:22. it may differ as some modern manufactures are going beyond the theoretical limits.

Thanks!
@Sharfudeen Mohamed Ibrahim • 18 Aug, 2015 AFAIK, we cannot use petrol in diesel engine because, petrol needs spark to ignite/burn, but diesel doesn't.


~sharfudeen
@SHIVA INGOLE • 20 Aug, 2015 Its all play about compression ratio.
@karthik kkr95 • 24 Aug, 2015
jaspal rapetrutela
I am a Mechanical Engineer from Dehradun and I've a query regarding petrol and diesel engines. I want to know why we can't use petrol in diesel engine? What are the changes in technology used that prevent us from doing it?
@karthik kkr95 • 24 Aug, 2015 Petrol engine works on ignition combustion basis.. and diesel engine works on injection combustion basis... ignition combustion is also called compression ignition.. the reason for using petrol in petrol in ignition combustion engine lies in the fact of compresdiom ratio.. petrol have low compression ratio when compared to diesel.. so petrol can be ignited just by compression.. whereas diesel cannot be done so.. thats the reason
@Umer999 • 20 Oct, 2015 Reference https://mobile.facebook.com/automechansys
Automotive Mechatronic Analysis
WILL PETROL ENGINE START IF DIESEL IS POURED INTO IT??

Petrol in diesel engine will never burn because self-ignition temperature of petrol is high and there is no spark plug in diesel engine but what about diesel in petrol engine? The problem is volatility of diesel is very less than the petrol, it will not vaporise easily. Thus no mixture of diesel and air is possible. As a result the diesel will not ignite with spark and engine won’t start

Signs of diesel in a petrol car

• Engine misfiring
• Engine won’t start
• Engine cuts out
• Smoky exhaust when driving
@Umer999 • 20 Oct, 2015 WILL PETROL ENGINE START IF DIESEL IS POURED INTO IT??

Petrol in diesel engine will never burn because self-ignition temperature of petrol is high and there is no spark plug in diesel engine but what about diesel in petrol engine? The problem is volatility of diesel is very less than the petrol, it will not vaporise easily. Thus no mixture of diesel and air is possible. As a result the diesel will not ignite with spark and engine won’t start

Signs of diesel in a petrol car

• Engine misfiring
• Engine won’t start
• Engine cuts out
• Smoky exhaust when driving
@Zillu • 20 Oct, 2015 If I put petrol in Diesel engine or vice-versa....whether the engine become useless...??

Or if it can be cleaned or recovered...whether it will have performance problem???


-Zillu
@Umer999 • 22 Oct, 2015 @Zillu
Engine can be cleaned and can work properly as before..
@Zillu • 23 Oct, 2015
Umer999
@Zillu
Engine can be cleaned and can work properly as before..
Thanks for the info.... 😀
@Sonusls • 19 Dec, 2015 mai i know wat is the max Km we can drive in Petrol and diesel at one time
@Ankita Katdare • 21 Dec, 2015
Sonusls
mai i know wat is the max Km we can drive in Petrol and diesel at one time
Your question is not clear. Are you asking the maximum distance travelled by a car with same amount of petrol or diesel?
@Sharfudeen Mohamed Ibrahim • 22 Dec, 2015
Sonusls
mai i know wat is the max Km we can drive in Petrol and diesel at one time
Its depends on CC of the engine.
@silver123 • 22 Dec, 2015 If you put diesel in a gasoline engine, the combustion won't happen. So it won't work. If you use petrol in diesel engine, there won't be smooth combustion but rather detonation(uncontrolled combustion) that may lead to damage of engine components after some time.
@Kamlesh Vora • 22 Dec, 2015 Such questions excites naughty minds of engineers.

Let me tell you all, the most important thing for combustion is AMOTIZATION of Fuel Particles. Now if you know properties of Petrol and Diesel well, you will know that Petrol and Diesel both have almost same burning point, but the importantly they are different in volatility. Petrol can vaporise at room temperature whereas Diesel need a jet spray and approx. 150bar to atomized it.

Now come to your topic, No diesel cannot burn in petrol engine at cold start. It may run for few minutes but it will misfire, will give black smoky with unburned Diesel, and maybe burst up gasket as Diesel Gas pressure is more than Petrol.

Correct me if I am wrong.
Thanks!

Related Posts

I thought of compiling a list of the coolest and the best whatsapp group names that you've been using for your respective groups. For the sake of convenience, we'll stick...
A simple good bye email or last working day mail ain't cool! We've some awesome templates that you can use. If you're looking for an amazing Last Working Day email...
Hello CEans, How to convert CGPA (10 Point Scale) to Percentage? Please help!
I heard many students are having a trouble registering on the TCS Portal, when it's quite straightforward actually. If you have problem in attaching photos or CV, Use internet explorer...
What is IES or Indian Engineering Services Exam? Union Public Services Commission (UPSC) conducts the Engineering Services Exam or ESE 2016 is an entrance exam for graduates who wish to...