Carryfast:
We don’t put spark plugs in diesel engines because they detonate diesel fuel using compression ignition under massive cylinder pressures and temperatures which would ignite petrol long before the spark does on a petrol engine.
Hi Carryfast,
Thanks for clearing up my last vestige of doubt that you knew what you’re talking about when you’re posting about flashpoint 
And I’m also glad that I’ve been able to preserve such a nugget of a quote fair and square, cos you couldn’t make up nonsense like that. 
We aren’t talking about cylinder compression pressures, OR FLASHPOINT, because we all accept that we all understand how a diesel engine ignites its fuel.
That one is in the bag and not in dispute. 
1.) The point that you consistently fail to grasp is that it is the LOW auto-ignition temperature for diesel fuel that allows auto-ignition.
2.) You also have failed to grasp that petrol needs a significantly HIGHER temperature before it will auto-ignite, but that’s the very reason that you’re correct when you say that a diesel engine can’t run on petrol.
The flashpoints of the two fuels have NO connection to 1 & 2 above. Period.
Big Jon’s dad:
Carryfast:
Big Jon’s dad:
To CF
Care to explain where easystart (ether) fits into your theory of ignition?
They don’t call it easy start for nothing.Like petrol it detonates/ignites ‘easier’ than diesel.Simples.
Yeh but you said petrol would ignite too soon and stop the engine from going over top dead centre didn’t you?
Hi BJD,
That’s because Carryfast still hasn’t understood what ‘flashpoint’ means. 
Big Jon’s dad:
Carryfast:
dieseldave:
Carryfast:
I’ve not confused anything in a comparison between the detonation resistance of diesel fuel versus petrol.There’s no way that petrol can withstand the cylinder pressures and temperatures generated in a diesel engine without detonating unlike diesel fuel.Simples.
Hi Carryfast,
Blimey, this is harder than pulling teeth.
I:
:idea: Sorry Carryfast, but unless you quickly own-up to an honest mistake, (and you’ve got this one very wrong) then you’ve been rumbled.
Now then Carryfast, it’s fair to say that you have your detractors and they may have a point…
I’m undecided, so please humour me a little… please clarify this:
Carryfast:
But unlike diesel that temperature is far too low so it’ll ignite too early under compression ignition when the piston is still on it’s way up the cylinder on the compression stroke.
Put it another way.What do you think the ignition timing would need to be on a spark ignition/petrol engine,if it was running with Diesel engine compression ratios and cylinder pressures,to prevent premature detonation of the mixture. 
If there’s an honest mistake there and I’ve got the issues very wrong then we can start using LPG in diesel engines which would make a big difference to the bottom line of most haulage operators. .Simples.
Great idea CF. Now how will we get the LPG to ignite?
Don’t ask me ask the experts but if the stuff can withstand diesel compression ratios without premature detonation and if the theory about diesel igniting at lower cylinder pressures and temperatures is correct,problem solved.
dieseldave:
Big Jon’s dad:
Carryfast:
Big Jon’s dad:
To CF
Care to explain where easystart (ether) fits into your theory of ignition?
They don’t call it easy start for nothing.Like petrol it detonates/ignites ‘easier’ than diesel.Simples.
Yeh but you said petrol would ignite too soon and stop the engine from going over top dead centre didn’t you?
Hi BJD,
That’s because Carryfast still hasn’t understood what ‘flashpoint’ means.
Yep I got that, That is why I asked about ether.
Big Jon’s dad:
Carryfast:
Big Jon’s dad:
To CF
Care to explain where easystart (ether) fits into your theory of ignition?
They don’t call it easy start for nothing.Like petrol it detonates/ignites ‘easier’ than diesel.Simples.
Yeh but you said petrol would ignite too soon and stop the engine from going over top dead centre didn’t you?
Which part of ignites/detonates ‘easier’ than diesel don’t you understand.But it won’t stop the engine going over tdc detonation just puts holes in the pistons and/or puts too much strain on the bottom end of the engine.
Big Jon’s dad:
Yep I got that, That is why I asked about ether.
Hi BJD,
Yes mate, I could instantly tell that you’d got it, but I was harbouring a forlorn hope that Carryfast might have realised his error.
No such luck though, so I guess we’re heading for 10 pages worth. 
Carryfast:
Big Jon’s dad:
Carryfast:
Big Jon’s dad:
To CF
Care to explain where easystart (ether) fits into your theory of ignition?
They don’t call it easy start for nothing.Like petrol it detonates/ignites ‘easier’ than diesel.Simples.
Yeh but you said petrol would ignite too soon and stop the engine from going over top dead centre didn’t you?
Which part of ignites/detonates ‘easier’ than diesel don’t you understand.But it won’t stop the engine going over tdc detonation just puts holes in the pistons and/or puts too much strain on the bottom end of the engine.
Why do we use ether to start cold engines?
Here’s a clue, these are autoignition temperatures
Diethyl ether: 160 °C (320 °F)
Diesel or Jet A-1: 210 °C (410 °F)
Guys there is no point carryfast just doesnt want to wrap his head around what he is failing to understand and thats autoignition temps. He is thinking 2 dimentional when 3 dimentions are called for. At this rate he will never get it. He has been provided the information and some links to find the answer lets just leave it at that.
dieseldave:
Carryfast:
We don’t put spark plugs in diesel engines because they detonate diesel fuel using compression ignition under massive cylinder pressures and temperatures which would ignite petrol long before the spark does on a petrol engine.
Hi Carryfast,
Thanks for clearing up my last vestige of doubt that you knew what you’re talking about when you’re posting about flashpoint
And I’m also glad that I’ve been able to preserve such a nugget of a quote fair and square, cos you couldn’t make up nonsense like that.
We aren’t talking about cylinder compression pressures, OR FLASHPOINT, because we all accept that we all understand how a diesel engine ignites its fuel.
That one is in the bag and not in dispute.
1.) The point that you consistently fail to grasp is that it is the LOW auto-ignition temperature for diesel fuel that allows auto-ignition.
2.) You also have failed to grasp that petrol needs a significantly HIGHER temperature before it will auto-ignite, but that’s the very reason that you’re correct when you say that a diesel engine can’t run on petrol.
The flashpoints of the two fuels have NO connection to 1 & 2 above. Period.
Was’nt talking about the flashpoint at all.My point is that Diesel can withstand higher cylinder pressures ‘before’ it detonates than petrol can.The issue of what the figures relating to flashpoint may or may not say does’nt alter the issue that petrol will detonate at far lower cylinder pressures than a diesel fuelled engine has at the point of compression ignition.But if I’m wrong then why have’nt we seen petrol/LPG powered,compression ignition trucks,in general use yet even at half the fuel costs.
Carryfast ummmmm correction you havent seen duel fuel application diesel engines. I have news for you in the 1950’s there were diesel engines you started on gas and then switched over to diesel.
Big Jon’s dad:
Carryfast:
Big Jon’s dad:
Carryfast:
Big Jon’s dad:
To CF
Care to explain where easystart (ether) fits into your theory of ignition?
They don’t call it easy start for nothing.Like petrol it detonates/ignites ‘easier’ than diesel.Simples.
Yeh but you said petrol would ignite too soon and stop the engine from going over top dead centre didn’t you?
Which part of ignites/detonates ‘easier’ than diesel don’t you understand.But it won’t stop the engine going over tdc detonation just puts holes in the pistons and/or puts too much strain on the bottom end of the engine.
Why do we use ether to start cold engines?
Here’s a clue, these are autoignition temperatures
Diethyl ether: 160 °C (320 °F)
Diesel or Jet A-1: 210 °C (410 °F)
But we don’t use it to run run them on when they’ve started.
Carryfast:
Was’nt talking about the flashpoint at all.My point is that Diesel can withstand higher cylinder pressures ‘before’ it detonates than petrol can.The issue of what the figures relating to flashpoint may or may not say does’nt alter the issue that petrol will detonate at far lower cylinder pressures than a diesel fuelled engine has at the point of compression ignition.But if I’m wrong then why have’nt we seen petrol/LPG powered,compression ignition trucks,in general use yet even at half the fuel costs.
You’ve been told several times that to obtain ignition from compression you have to reach the temperature of autoignition. If you don’t reach a high enough temperature you won’t get ignition unless you apply a spark.
Here again are the autoignition temperatures for a range of fuels.
Diethyl ether: 160 °C (320 °F)
Diesel or Jet A-1: 210 °C (410 °F)
Gasoline (Petrol): 246—280 °C (475—536 °F)
Butane: 405 °C (761 °F)
Brentanna:
Carryfast ummmmm correction you havent seen duel fuel application diesel engines. I have news for you in the 1950’s there were diesel engines you started on gas and then switched over to diesel.
But we’re not talking about switching them back over to diesel when they’ve started.We’re talking about running a diesel engine on LPG versus running a spark ignition petrol engine on LPG.‘If’ it’s possible to run a compression ignition engine on LPG,in just the same way as a spark ignition engine,then I’m wrong.But where are they .
Here are some more for you carryfast see we can provide the proof where is yours?
The Auto-Ignition Temperature - or the minimum temperature required to ignite a gas or vapor in air without a spark or flame being present - are indicated for some common fuels below:
Fuel or Chemical Temperature
(oC) (oF)
Acetaldehyde 175 347
Acetone 465 869
Acetylene 305 581
Anthracite - glow point 600 1112
Benzene 560 1040
Bituminous coal - glow point 454 850
Butane 420 788
Carbon 700 1292
Carbon - bi sulfide 149 300
Carbon monoxide 609 1128
Charcoal 349 660
Coal-tar oil 580 1076
Coke 700 1292
Cyclohexane 245 473
Diethyl ether 160 320
Ethane 515 859
Ethylene 490 914
Ehtyl Alcohol 365 689
Fuel Oil No.1 210 410
Fuel Oil No.2 256 494
Fuel Oil No.4 262 505
Heavy hydrocarbons 750 1382
Hydrogen 500 932
Gas oil 336 637
Gasoline 280 536
Gun Cotton 221 430
Kerosene 295 563
Isobutane 462 864
Isobutene 465 869
Isooctane 447 837
Isopentane 420 788
Isopropyl Alcohol 399 750
Light gas 600 1112
Light hydrocarbons 650 1202
Lignite - glow point 526 979
Methane (Natural Gas) 580 1076
Methyl Alcohol 385 725
Naphtha 550 1022
Neoheaxane 425 797
Neopentane 450 842
Nitro-glycerine 254 490
n-Butane 405 761
n-Heptane 215 419
n-Hexane 225 437
n-Octane 220 428
n-Pentane 260 500
n-Pentene 298 569
Oak Wood - dry 482 900
Peat 227 440
Petroleum 400 752
Pine Wood - dry 427 800
Phosphorous, amorphous 260 500
Phosphorous, transparent 49 120
Production gas 750 1382
Propane 480 842
Propylene 458 856
p-Xylene 530 986
Rifle Powder 288 550
Toluene 530 849
Semi anthracite coal 400 752
Semi bituminous coal - glow point 527 980
Styrene 490 914
Sulphur 243 470
Wood 300 572
Xylene 463 867
The flammable (explosive) range is the range of a gas or vapor concentration
engineeringtoolbox.com/fuels … d_171.html
Carryfast:
Brentanna:
Carryfast ummmmm correction you havent seen duel fuel application diesel engines. I have news for you in the 1950’s there were diesel engines you started on gas and then switched over to diesel.
But we’re not talking about switching them back over to diesel when they’ve started.We’re talking about running a diesel engine on LPG versus running a spark ignition petrol engine on LPG.‘If’ it’s possible to run a compression ignition engine on LPG,in just the same way as a spark ignition engine,then I’m wrong.But where are they .
They are here: cleanairpower.com/duel-technology.php
New technology takes a while to get established and if it lives up to the initial promises it expands exponentially. Expect to see more of this technology at least until HMG decides to put up duty on the cheap fuel.
Carryfast are you really that ■■■■■■■ stupid I mean really. There have been people posting on here that have used them just because you live in such a small corner of the world that you havent doesnt mean they do not exist. Have you ever seen a neutron ? How about s single molecule of hydrogen. They exist dont they or are you going to argue because you havent seen them that they dont?
Well well well didnt I explain about 4 pages ago that that is how they worked and that they can go as low as 3% diesel in theory. BJD thanks for that link now he has seen them he can shut the ■■■■ up
Big Jon’s dad:
Carryfast:
Was’nt talking about the flashpoint at all.My point is that Diesel can withstand higher cylinder pressures ‘before’ it detonates than petrol can.The issue of what the figures relating to flashpoint may or may not say does’nt alter the issue that petrol will detonate at far lower cylinder pressures than a diesel fuelled engine has at the point of compression ignition.But if I’m wrong then why have’nt we seen petrol/LPG powered,compression ignition trucks,in general use yet even at half the fuel costs.
You’ve been told several times that to obtain ignition from compression you have to reach the temperature of autoignition. If you don’t reach a high enough temperature you won’t get ignition unless you apply a spark.
Here again are the autoignition temperatures for a range of fuels.
Diethyl ether: 160 °C (320 °F)
Diesel or Jet A-1: 210 °C (410 °F)
Gasoline (Petrol): 246—280 °C (475—536 °F)
Butane: 405 °C (761 °F)
If those figures are correct and/or relevant to the issue the we ‘should’ be able to use petrol/LPG in compression ignition engines and we ‘should’ be able to run spark ignition petrol engines at diesel engine compression ratios.However why do spark ignition petrol engines detonate a fuel with a higher auto ignite figure,at far lower compression pressures,than are needed by compression ignition engines to detonate a fuel with a lower auto ignite figure .
here is a clue carryfast how about the air to fuel ratio 
doesnt that equate into you prehistoric theories somewhere