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Old 11-18-2006, 07:55 AM
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Main reason, fuel economy?

The only reason or main reason someone would buy a diesel is fuel economy, right? What would be other reasons someone would buy a diesel?
Old 11-18-2006, 09:36 AM
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Originally Posted by IanGreening
The only reason or main reason someone would buy a diesel is fuel economy, right? What would be other reasons someone would buy a diesel?
Torque.
Old 11-18-2006, 10:12 AM
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Originally Posted by IanGreening
What would be other reasons someone would buy a diesel?
Legendary reliability and longevity.
Old 11-18-2006, 12:15 PM
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Originally Posted by cyclerider
Legendary reliability and longevity.
We can hope, but these new CDI engines are a completely different breed of cat, Let's keep our fingers crossed.
Old 11-18-2006, 12:45 PM
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Originally Posted by IanGreening
The only reason or main reason someone would buy a diesel is fuel economy, right? What would be other reasons someone would buy a diesel?
Not really. I only get 25MPG.

I have a diesel because I hate the sloppy, inefficient, and foul gasoline engines (Not MB, but ANY gas engine in general.).
Old 11-18-2006, 12:59 PM
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Originally Posted by cyclerider
Legendary reliability and longevity.
That's it in a nutshell. A typical gas engine is good for about 200-250K miles. A diesel is easily double that. Even a well used turbo diesel in a car or light truck should go 500k before even needing a valve job. If you drive alot or haul alot, the diesel is the way to go. Diesels are most effectively used for large loads or long steady runs. Today's gas vs. diesel pick-ups are about the same mileage when empty. But if you hitch up your travel trailer, you diesel will only lose a couple of MPG, where the gasser would be half or less.

One part that makes them last so long is the pistons themselves. They have small passages drilled into the top of them that lead to the rings. Under cylinder pressure, they are forced to expand against the cylinder walls, making the best seal possible. It's not alot of pressure, but it is very effective.

In a car it's the reliability. Not much ever goes wrong with them. If you keep your car a long time, this pays off. In most of the rest of the world, diesel is the best because of that, and the flexibility of it. It can be used for heaters, lamps, etc. Over here, we don't need it for that. Not to mention that most of us "spoiled Americans" (per studies) say that they dislike the noise and smell they make. The automakers are addressing this now with quieter engines and better polution controls.

And I hope that they will become more mainstream than gas engines. Don't get me wrong, I love my gas engines. But overall I would love to be mostly diesel, running the biofuel.
Old 11-18-2006, 04:56 PM
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Originally Posted by Wyle E. Coyote
That's it in a nutshell. A typical gas engine is good for about 200-250K miles. A diesel is easily double that. Even a well used turbo diesel in a car or light truck should go 500k before even needing a valve job. If you drive alot or haul alot, the diesel is the way to go. Diesels are most effectively used for large loads or long steady runs. Today's gas vs. diesel pick-ups are about the same mileage when empty. But if you hitch up your travel trailer, you diesel will only lose a couple of MPG, where the gasser would be half or less.

One part that makes them last so long is the pistons themselves. They have small passages drilled into the top of them that lead to the rings. Under cylinder pressure, they are forced to expand against the cylinder walls, making the best seal possible. It's not alot of pressure, but it is very effective.

In a car it's the reliability. Not much ever goes wrong with them. If you keep your car a long time, this pays off. In most of the rest of the world, diesel is the best because of that, and the flexibility of it. It can be used for heaters, lamps, etc. Over here, we don't need it for that. Not to mention that most of us "spoiled Americans" (per studies) say that they dislike the noise and smell they make. The automakers are addressing this now with quieter engines and better polution controls.

And I hope that they will become more mainstream than gas engines. Don't get me wrong, I love my gas engines. But overall I would love to be mostly diesel, running the biofuel.
I couldn't say it any better..........all hail Wyle E. Coyote
Old 11-18-2006, 05:19 PM
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Originally Posted by Wyle E. Coyote
That's it in a nutshell. A typical gas engine is good for about 200-250K miles. A diesel is easily double that. Even a well used turbo diesel in a car or light truck should go 500k before even needing a valve job. If you drive alot or haul alot, the diesel is the way to go. Diesels are most effectively used for large loads or long steady runs. Today's gas vs. diesel pick-ups are about the same mileage when empty. But if you hitch up your travel trailer, you diesel will only lose a couple of MPG, where the gasser would be half or less.

One part that makes them last so long is the pistons themselves. They have small passages drilled into the top of them that lead to the rings. Under cylinder pressure, they are forced to expand against the cylinder walls, making the best seal possible. It's not alot of pressure, but it is very effective.

In a car it's the reliability. Not much ever goes wrong with them. If you keep your car a long time, this pays off. In most of the rest of the world, diesel is the best because of that, and the flexibility of it. It can be used for heaters, lamps, etc. Over here, we don't need it for that. Not to mention that most of us "spoiled Americans" (per studies) say that they dislike the noise and smell they make. The automakers are addressing this now with quieter engines and better polution controls.

And I hope that they will become more mainstream than gas engines. Don't get me wrong, I love my gas engines. But overall I would love to be mostly diesel, running the biofuel.
Excellent writeup. The combination of torque, fuel efficiency, and reliability are the reasons behind my love of the new diesels.
Old 11-18-2006, 07:17 PM
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What about the Bluetec engines?

Originally Posted by Wyle E. Coyote
That's it in a nutshell. A typical gas engine is good for about 200-250K miles. A diesel is easily double that. Even a well used turbo diesel in a car or light truck should go 500k before even needing a valve job. If you drive alot or haul alot, the diesel is the way to go. Diesels are most effectively used for large loads or long steady runs. Today's gas vs. diesel pick-ups are about the same mileage when empty. But if you hitch up your travel trailer, you diesel will only lose a couple of MPG, where the gasser would be half or less.

One part that makes them last so long is the pistons themselves. They have small passages drilled into the top of them that lead to the rings. Under cylinder pressure, they are forced to expand against the cylinder walls, making the best seal possible. It's not alot of pressure, but it is very effective.

In a car it's the reliability. Not much ever goes wrong with them. If you keep your car a long time, this pays off. In most of the rest of the world, diesel is the best because of that, and the flexibility of it. It can be used for heaters, lamps, etc. Over here, we don't need it for that. Not to mention that most of us "spoiled Americans" (per studies) say that they dislike the noise and smell they make. The automakers are addressing this now with quieter engines and better polution controls.

And I hope that they will become more mainstream than gas engines. Don't get me wrong, I love my gas engines. But overall I would love to be mostly diesel, running the biofuel.
I read that the latest diesel engines including the Bluetec ones are not as reliable as the older diesels without all the tree hugging Peoples Republic of California laws in 2006. To begin with the Piezzo injection needed for atomization and complete combustion without diesel fuel residue (soot) is imposing a terrible strain on the injectors. The fuel injection pressure in the Bluetec diesel injector is 20,000 pounds per square inch. Yes, twenty grand of pressure enough to punch a hole in steel and concrete. They are putting more holes in these injectors too (more holes in a tube means less strength). How the engine and injectors can withstand this for a million miles compared with a conventional 1980s diesel with a fraction of the pressure I just do not know.

Next Bluetec buyers have to think of the 3 "filters" that need to be replaced eventually at 200,000 miles or so when the cars are worth zilch. Are they going to cost $1,000 each? $2,000 each? That means 3 to 6 grand for an old car. Are you still going to hug that tree guys?

My advice is buy a 2006 straight six 320 CDi when you still can. It has no particulate filter and no urea injection. You can burn all kinds of shjt without jeopardising those filters so loved by Sierra Club chaps. Buy them and drive with bio-diesel, old black engine oil, oil you got for free from your local KFC outlet or any fossil fuel while the Bluetec guys are looking everywhere for ULSD.

That feels great.
Old 11-18-2006, 07:28 PM
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Trees or Zoom?

Originally Posted by VonTurboW123
I couldn't say it any better..........all hail Wyle E. Coyote
I am not Sierra Club but I am not pro-pollution either. I just love your American way of life and do not like to be told by non-inhaling presidents what to do.

In the 1970s Peant "PP" Carter told the world oil will run out in 20 years. He lied. The acid rain group (on "acid" no doubt) told us that catalytic converters will save us from big block V-8 engines and the panacea for the energy crisis.

Today I am still driving a 560 SEL, an E-55, a Suburban and a Camry and a Rolls Royce occasionally. I have no problem finding premium gas. Carter was wrong or was lying.

All of my cars are catalyst cars and the Sierra chaps are saying we should do more. More of what? What they wanted in 1971 they got and now they want MORE! They are anti-car.

If they believe in what they preach they should immediately sell all their cars and walk. Or travel in buggies like the Amish. I have respect for the Amish.

I dis the hypocritical "tree-huggers" including the Sierras.
Old 11-19-2006, 02:15 AM
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I know of no "tree hugger" that is true to his or her cause. If they aren't living in a mud hut and eating nothing but berries, they are hypocrates in my opinion.

As far as the new low sulfer diesel (aka: LSD.... isn't that a strange acyronym? ), it isn't going to be bad for the older engines. Which is my area of concern. Why? Because we all know that most of the new cars are just a waste of good metal, what little they really have.

I've never heard of this Bluetec, but if you believe that these injectors are running 20,000 PSI, then I wanna talk to you about some real estate. IIRC, 6,000 PSI is what a water-jet cutter runs to slice through hardened steel. The top of those pistons better be made of armor plate, or the first squirt of fuel is gonna waste the whole motor.

The automakers have known for decades that 70% of their income comes from the shop and not from the sale. Why do you think that cars like the Studebaker went out of business? Those were the Lexus' of their day. That company had integrity to the last day. Build the better car rather than rip off the public. The big 3 don't make any money if your car isn't breaking down. So it isn't in their best intrest to sell you something that is going to last.

My advice; if a refrigerator magnet can't stick to the dashboard somewhere, stay away. Or at least, buyer beware. Spending more or having the newest thing doesn't make it the best.
Old 11-19-2006, 02:52 AM
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Originally Posted by Wyle E. Coyote
I've never heard of this Bluetec
...
As far as the new low sulfer diesel (aka: LSD....
...
but if you believe that these injectors are running 20,000 PSI, then I wanna talk to you about some real estate. IIRC, 6,000 PSI is what a water-jet cutter runs to slice through hardened steel. The top of those pistons better be made of armor plate, or the first squirt of fuel is gonna waste the whole motor.
First, BlueTec from Mercedes' website http://www4.mercedes-benz.com/specia...x_nocom_en.htm

Second, it's ULSD. Ultra low sulfur diesel.

third, where is this real estate?
From http://cars.about.com/od/thingsyoune...ag_BLUETEC.htm
"the BLUETEC's injectors are fed by a central fuel rail that is supplied with fuel at extremely high pressure (approx. 23,000 psi)."
The pistons are aluminum alloy.

And BTW, waterjets work at 40,000psi to 87,000psi depending on how old it is.

I suggest you go hit the books.....
Old 11-19-2006, 06:10 AM
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Originally Posted by 240D 3.0T
"the BLUETEC's injectors are fed by a central fuel rail that is supplied with fuel at extremely high pressure (approx. 23,000 psi)."
.
And other systems are running at even higher pressures. See the attached article.

Well, I can't upload a PDF file. You can find a link to it here:

http://www.pointedthree.com/disc/for...d=53595#M53595
Old 11-19-2006, 11:49 AM
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Originally Posted by 240D 3.0T
First, BlueTec from Mercedes' website http://www4.mercedes-benz.com/specia...x_nocom_en.htm
Interesting....

Originally Posted by 240D 3.0T
Second, it's ULSD. Ultra low sulfur diesel.
I knew that, I just left out the "U". I just think that it's a funny coincidence. But my sense of humor is a strange one anyway.

Originally Posted by 240D 3.0T
third, where is this real estate?
From http://cars.about.com/od/thingsyoune...ag_BLUETEC.htm
"the BLUETEC's injectors are fed by a central fuel rail that is supplied with fuel at extremely high pressure (approx. 23,000 psi)."
The pistons are aluminum alloy.
Also very interesting...

Originally Posted by 240D 3.0T
And BTW, waterjets work at 40,000psi to 87,000psi depending on how old it is.

I suggest you go hit the books.....
When i first heard about the waterjet, the guy must have made a typo, because I recall he said it ran at about 6,000 PSI. He probably meant to say 60,000. Thanks for clearing that up for me.

All those high tech items in those articles just makes me more leery of the new technology. After about the third paragraph of the tech stuff, it starts to blend into one big long to me. The science is going way over my head. And with that much science going into it, it makes me leery of it's reliability. Give me an "old, inefficient, glow plug motor" anyday.

That's my two cents.
Old 11-19-2006, 10:03 PM
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Originally Posted by Wyle E. Coyote
Interesting....



I knew that, I just left out the "U". I just think that it's a funny coincidence. But my sense of humor is a strange one anyway.



Also very interesting...



When i first heard about the waterjet, the guy must have made a typo, because I recall he said it ran at about 6,000 PSI. He probably meant to say 60,000. Thanks for clearing that up for me.

All those high tech items in those articles just makes me more leery of the new technology. After about the third paragraph of the tech stuff, it starts to blend into one big long to me. The science is going way over my head. And with that much science going into it, it makes me leery of it's reliability. Give me an "old, inefficient, glow plug motor" anyday.

That's my two cents.
Mr. Coyote,

Exactly what I think and said previously. Go buy a 2005-2006 E320 CDi. Just high tech enough without going overboard. An ideal one would be chipped by Kleemann or Carlsson to 240 horses and 400 pound foot torque and wearing 19 inch, 9 twin spoke Denbola wheels. The Bluetecs engines sound scary and expensive, particularly the ones coming in 2008 MY.
Old 11-19-2006, 10:06 PM
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The 20000 + PSI running in the common rail system is enough to chop one or more human fingers off.

The older IDI design ('99 E300 turbodiesels and earlier) used only a fraction of that amount of fuel (about 1600 - 2000 psi) to make its power.
Old 11-24-2006, 02:43 AM
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I get between 50 and 66mpg from my c220 cdi on my journey to work (45 mles of which 38 are highway), engine is silent when the car is moving.
Fantastic economy (I once got 70mpg over the same journey, will post pic of trip meter but I have noticed a drop in economy now that the mornings are very cold)
Old 11-24-2006, 09:42 AM
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70 miles per imperial or US gallon?

Originally Posted by ash-c32
I get between 50 and 66mpg from my c220 cdi on my journey to work (45 mles of which 38 are highway), engine is silent when the car is moving.
Fantastic economy (I once got 70mpg over the same journey, will post pic of trip meter but I have noticed a drop in economy now that the mornings are very cold)
That sounds an awful lot. I had a 5 speed Jetta TDi (3,000 lbs) for 4 years and the very best I had achieved in highway driving was 50 mpg. 70 mpg is the regular mileage of Smart four twos.
Old 11-24-2006, 09:45 AM
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Injection Pressure

Originally Posted by DslBnz
The 20000 + PSI running in the common rail system is enough to chop one or more human fingers off.

The older IDI design ('99 E300 turbodiesels and earlier) used only a fraction of that amount of fuel (about 1600 - 2000 psi) to make its power.
Do you know the injection pressure of the 2005-2006 straight six 320CDi engines?

I have the option of getting either a slightly used one or a new 2007 Bluetec, both the same price. I read somewhere recently that the last straight six engines have injection pressures somewhere between the 1999 ones and the Bluetec, around 10,000 PSi.
Old 11-24-2006, 10:30 AM
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Originally Posted by harkgar
That sounds an awful lot. I had a 5 speed Jetta TDi (3,000 lbs) for 4 years and the very best I had achieved in highway driving was 50 mpg. 70 mpg is the regular mileage of Smart four twos.
Imperial gallon in the UK?
Old 11-25-2006, 08:15 PM
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Originally Posted by harkgar
Do you know the injection pressure of the 2005-2006 straight six 320CDi engines?

I have the option of getting either a slightly used one or a new 2007 Bluetec, both the same price. I read somewhere recently that the last straight six engines have injection pressures somewhere between the 1999 ones and the Bluetec, around 10,000 PSi.
20,000 PSI. The common rail, being direct injection, requires much greater pressures than indirect injection engines.

Really, the E320CDI I6 has not been around long enough to be credited with long term durability. Only after 10 - 15 years, and a minimum of 250K miles under its belt of trouble free 50/50 urban/rural mixed driving will any engine prove its worth.

The V6 just came out. No engine that has come from Mercedes, save the 61x series engines, accumulates miles without their individual "quirks".

Give it a chance.
Old 11-25-2006, 08:31 PM
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Originally Posted by harkgar
Do you know the injection pressure of the 2005-2006 straight six 320CDi engines?

I have the option of getting either a slightly used one or a new 2007 Bluetec, both the same price. I read somewhere recently that the last straight six engines have injection pressures somewhere between the 1999 ones and the Bluetec, around 10,000 PSi.
The injection pressure on the inline 6 cyl CDI is exactly the same as the Bluetec - c. 23,000 psi.

I have to assume that anyone opposing more stringent emission controls has never spent any time in the LA Basin. Much progress has been made, but there is still a long way to go. This is a problem that technology created and one that technology must solve.
Old 11-25-2006, 09:10 PM
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Originally Posted by khaug
I have to assume that anyone opposing more stringent emission controls has never spent any time in the LA Basin. Much progress has been made, but there is still a long way to go. This is a problem that technology created and one that technology must solve.
Going from carburetors to fuel injection and IDI to DI diesels alone have made a huge impact in the environment. The catalytic converters, EGR, and air injection are small beans compared to those steps.

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