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Why does diesel fuel exist?

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Originally posted by: Fenixgoon
Originally posted by: Zenmervolt
You are mistaken. Diesels have compression ratios well above 16:1. The highest I've seen in a gasoline engine is around 12:1. It's the very high compression ratio that allows the diesel to ignite without a spark plug. If you put diesel oil in a gasoline engine, it may not even ignite at all, even with the spark plugs firing.

ZV
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compression ratio has to do with temp/pressure, no? at least i got the spark plug part right 😀

<--- not a car buff
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Yes, but the diesel needs much higher compression ratios (i.e. much higher temperature and pressure) to cause the fuel to self-ignite. If you put 87 octane fuel into a car with 12:1 compression, the mixture will self-ignite before the spark plug fires. If you put diesel in that same engine, it won't get hot enough even with the spark plug to sustain combustion.

ZV
 
Originally posted by: IHateMyJob2004
Originally posted by: Accipiter22
just curious as to why diesel engines exist...
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Actually, looking back at history, the question should be ... why do gasoline engines exist?
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For all the reasons I stated earlier... It is only within the last 10 to 15 years that diesel has become a viable alternative to gasoline in everyday applications. Prior to the 1990's, diesel was simply not suited to anything other than special applications that could overlook the myriad serious drawbacks that diesel used to carry.

ZV
 
Originally posted by: Zenmervolt
Originally posted by: vi_edit
The real question is, why does gasoline exist?

Diesel engines are more efficient and typically last much longer than a gasoline equivalent.
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Because until VERY recently, diesel was incredibly inconvenient. Until the 1990's diesels required glow-plugs and at best a 30 second wait before you could start the engine (some engines required much longer), diesel congeals at low temperatures (I remember as a kid in 1996 or so in Ohio we had a cold snap in the middle of winter and school was canceled for two days because all the diesel in the busses congealed and none would start), diesel engines used to be almost impossible to start at low temps (some semis had small gasoline engines to start their diesel engines during winter), diesels used to emit vast amounts of particulate emissions that caused severe asthma problems (similar to heavy coal emissions), and the NOx emissions from diesels used to be abominable.

It has only been in the past 10-15 years that diesel has become a viable everyday alternative to gasoline and the engines still cost more to produce.

ZV
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That happens because the fuel companies wait too long to deiliver "Winter Mix"
diesel fuel.

When mixed properly Winter mix is good to -25f.

Very often,the first cold spell happens when the trucks still have straight #2 fuel oil/
diesel,which gels at about 25+f.

If you know a cold spell is coming then you can add Anti-gel additive,and some #1 diesel
or Kerosene to the fuel tanks.

This happens at my work sometimes,we get a around zero cold snap,and the trucks/loaders etc start to gel up.

I have been bitching for 20 years that starting October 1st our fuel should be
70/30% which is good to about -10f or so.And any fuel after Dec 15th should be 60/40%

I get told whenever I mention it,that this costs a little more money. :|

A Diesel Truck engine makes more torque than any gasoline engine,
and torque is what is needed to move a heavy vehicle.
 
Originally posted by: cavemanmoron
Originally posted by: Zenmervolt
Originally posted by: vi_edit
The real question is, why does gasoline exist?

Diesel engines are more efficient and typically last much longer than a gasoline equivalent.
Click to expand...
Because until VERY recently, diesel was incredibly inconvenient. Until the 1990's diesels required glow-plugs and at best a 30 second wait before you could start the engine (some engines required much longer), diesel congeals at low temperatures (I remember as a kid in 1996 or so in Ohio we had a cold snap in the middle of winter and school was canceled for two days because all the diesel in the busses congealed and none would start), diesel engines used to be almost impossible to start at low temps (some semis had small gasoline engines to start their diesel engines during winter), diesels used to emit vast amounts of particulate emissions that caused severe asthma problems (similar to heavy coal emissions), and the NOx emissions from diesels used to be abominable.

It has only been in the past 10-15 years that diesel has become a viable everyday alternative to gasoline and the engines still cost more to produce.

ZV
Click to expand...


That happens because the fuel companies wait too long to deiliver "Winter Mix"
diesel fuel.

When mixed properly Winter mix is good to -25f.

Very often,the first cold spell happens when the trucks still have straight #2 fuel oil/
diesel,which gels at about 25+f.

If you know a cold spell is coming then you can add Anti-gel additive,and some #1 diesel
or Kerosene to the fuel tanks.

This happens at my work sometimes,we get a around zero cold snap,and the trucks/loaders etc start to gel up.

I have been bitching for 20 years that starting October 1st our fuel should be
70/30% which is good to about -10f or so.And any fuel after Dec 15th should be 60/40%

I get told whenever I mention it,that this costs a little more money. :|

A Diesel Truck engine makes more torque than any gasoline engine,
and torque is what is needed to move a heavy vehicle.
Click to expand...
I understand all that. My post was to point out that diesel wasn't viable for everyday automotive use until recently because it required additional attention. I fully understand that diesel was and is worth those downsides for hauling and other special applications.

ZV
 
Diesel ... because $3.45 per gallon is major profit compared to only $2.19 for unleaded gasoline 😛

The real answer is that diesel engines produce amazing amounts of torque at low RPMs which is a requirement for trucks.
 
Originally posted by: CorCentral
Elly---- Dirty burning fuels should be taxed more...... Plain and simple.

K1052---- Sudden? Who said anything about sudden? They're already paying more at the pump! Make cleaner burning engines!
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You do realize that the diesel of today isn't the same as the dirty diesel of yesterday, and the diesel of tomorrow is even cleaner?

I think it's funny that diesel is more expensive than gasoline in the first world, considering it's cheaper to produce. In the third world it's always cheaper.
 
Originally posted by: mjrpes3
I wonder why type of MPG you'd get if you combined these three factors

1. Diesal
2. Hybrid
3. Small form factor
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IDK but im sure that would be freeking impressive
 
Originally posted by: DurocShark

TPAD
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Make that $40 for you. :|

Kids and their silly acronyms and monkey see, monkey must do attitude. Where's the change of culture? :disgust:

 
Originally posted by: jagec
Originally posted by: CorCentral
Elly---- Dirty burning fuels should be taxed more...... Plain and simple.

K1052---- Sudden? Who said anything about sudden? They're already paying more at the pump! Make cleaner burning engines!
Click to expand...

You do realize that the diesel of today isn't the same as the dirty diesel of yesterday, and the diesel of tomorrow is even cleaner?

I think it's funny that diesel is more expensive than gasoline in the first world, considering it's cheaper to produce. In the third world it's always cheaper.
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Yeah it is the same in the US. We don't have the low sulfur diesel yet.
 
compression ratio would be too high in a diesel to use normal petrol

diesel engines typically have liek 17:1 compression ratio, normal petrol engines are much lower more around 10:1.
 
Originally posted by: Vic
Horsepower is a marketing tool for gasoline engine makers. Torque is where it's at and diesels make torque in boatloads.
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QFT
The more Torque at low rpm is better then high ammounts of HP anyday.
 
Originally posted by: funboy42
Originally posted by: Vic
Horsepower is a marketing tool for gasoline engine makers. Torque is where it's at and diesels make torque in boatloads.
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QFT
The more Torque at low rpm is better then high ammounts of HP anyday.
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Explain that to Honda 😉
 
I get 22MPG while gas truck with the V10 gets 12.

I have 600 ftlbs of torque while the gas engine with the V10 has 470.

Clear enough?
 
Originally posted by: YoshiSato
Originally posted by: lobadobadingdong

Oil companies have invested billions in gasoline refinerys/distrobution, and are not about to let them go to waste (anyone else notice thier quarterly profits lately?)
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They made like 10 billion(10,000,000,000) dollars in the past 4 months at a 89% profit.
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Your number is off. $10,000,000,000 was the profit of just ONE oil company-Exxon Mobil, over the past 3 months. Their revenue was a record-breaking $100,000,000,000 during this short period. Combined the powerful 6 oil companies have around $40,000,000,000 - $50,000,000,000 in summer profits on revenue of $400,000,000,000 - $500,000,000,000.
 
I will add that the $40 - $50 billion is just the NET profit of the companies (i.e. after everyone has taken their cut). The GROSS profit of the oil companies is around 60% of their revenue, which means their summer profit is around $250 - $300 billion.
 
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