question for genesis

[67hat34c]

i cut and copied this about vw diesel cars, they appear to be PP cars, what do you think.

Some of the earlier diesels to make it to our shores over the next few years will only be available in 45 states; California, Maine, Massachusetts, New York, and Vermont have all adopted stricter emissions regulations for diesels that bar some vehicles from entry. Using technology developed under the BlueTec cooperative formed by Mercedes-Benz and Volkswagen, the Jetta TDI will slip by these stricter regulations without resorting to a urea-based exhaust treatment, as many BlueTec labeled models will.



Nitrogen oxides (NOx) are, along with particulate emissions (soot), the biggest hurdles facing diesels in the U.S. Most BlueTec vehicles will control NOx by injecting a urea-based solution called AdBlue into the exhaust system upstream of a catalytic converter that specifically targets NOx. In that catalytic converter, the ammonia in the urea reacts with the NOx in the exhaust gas and neutralizes it into nitrogen and water.


Volkswagen's Jetta TDI will manage without a urea injection system by using a NOx-storage catalyst. Like the particulate filters in place on this car as well as other diesels, this catalyst is basically a trap that temporarily holds the offensive emissions. Periodically, the engine will switch to an air-fuel mixture that will burn off the material in the traps.

 

[Genesis]

Yep.

The urea-injection system sucks. The particulate trap has been on the cars for a while - mine has one.....

 

[jim rosenthal]

If the item that VW is using is a trap oxidizer, I think MB used something like this a few years back with pretty disastrous results. They ended up having to warranty them for life, and a few are still out there. It sounds like the same thing....

 

[MikeP]

Yep, MB placed the Trap oxidizer upstream from the turbocharger. So when the trap oxidizer failed, where do you suppose all those metal pieces went?

Undoubtedly one of the stupidest engine design flaws I could ever imagine. A 3rd grader would have been able to figure out that when the TO began disentegrating (NORMAL WEAR for God's sake) it only had about 4" to fly before hitting the 100,000+ RPM impellor blades.

My wife had a 300SDL with that outstanding design! As Jim said, MB got to replace the TO and turbo twice before they figured out that they could eliminate the TO and put a device in the exhaust pipe that did the job similar to gas-engined cat converter and located in the same place. DUH!

I mean, really...how do designers that are actually paid money come up with such incompetent stuff?

 

[Boss Lady]

because the computer did not tell them they were being stupid! We still need humans with a brain and real experience to know when the computer is lying to you. LOL Somebody has the tag line "I want to live in theory, everything works there!" I find it real funny that a german engineer made this mistake, since they are so anal about engineering perfection. Maybe it was one of the Diamler/Chrysler engineers that did it. LOL

 

[Genesis]

The one on the VW is downstream of the turbo; its part of the catalytic converter (yes, it really does have one!)

 

[Freebird]

Okay, is it safe to assume I don't want to put a couple of these engines in ole' Freebird to make her more attractive in the buyer's market?

 

[67hat34c]

so they inject Urin?

 

[Wild Bill]

[I mean, really...how do designers that are actually paid money come up with such incompetent stuff?]

I think it's called college. The place where a bunch of overpaid left wing boobs fill our kids heads with political views, but fail to teach them what they are there to learn. The kids come out of college and don't have enough sense to pour piss out of a boot.

 

[yachtsmanbill]

UREA is great stuff-- sparkies, toothpaste, pretzels and formaldehyde for marine glue !! ws
Industrial use

Urea's commercial uses include:

* As a raw material for the manufacture of plastics specifically, urea-formaldehyde resin.
* As a raw material for the manufacture of various glues (urea-formaldehyde or urea-melamine-formaldehyde). The latter is waterproof and is used for marine plywood.
* As a component of fertilizer and animal feed, providing a relatively cheap source of fixed nitrogen to promote growth.
* As an alternative to rock salt in the deicing of roadways and runways. It does not promote metal corrosion to the extent that salt does.
* As an additive ingredient in cigarettes, designed to enhance flavour.
* Sometimes used as a browning agent in factory-produced pretzels.
* As an ingredient in some hair conditioners, facial cleansers, bath oils and lotions.
* It is also used as a reactant in some ready-to-use cold compresses for first-aid use, due to the endothermic reaction it creates when mixed with water.
* Active ingredient for diesel engine exhaust treatment AdBlue and some other SCR systems.
* Used, along with salts, as a cloud seeding agent to expedite the condensation of water in clouds, producing precipitation.
* The ability of urea to form clathrates (also called host-guest complexes, inclusion compounds, and adducts) was used in the past to separate paraffins.
* As a flame-proofing agent.
* As a clean burning fuel for motor vehicles and stationary engines.
* As a NOx-reducing reactant in diesel exhaust.
* As an ingredient in many tooth whitening products.

 

[MikeP]

Re the MB design - this model was a 1987 - Waaay before the Chrysler acquisition. It was strictly a German concoction. My wife has had 3 MBs from 1987, Frankly, I think they are VASTLY overated as an auto. I believe the "German Engineering" thing is a leftover from 40 years ago that hasn't been current in a long time. Some of the "design" is laughable from a mechanical and fixable viewpoint...and you have to fix them a lot!

 

[Genesis]

My problem with the "reactant" nonsense is that its another consumable that you, the driver, must maintain and replenish (at your cost)

Its also BS. Diesels are cleaner than gas engines if you include all pollutants (including the CO2); CO2 production dwarfs all others, and is intentionally omitted in the comparisons to make diesels look bad.

In other words, its politics.

 

[Avenger]

Mercedes-Benz started to hit the skids in 1986 when the CEO became a financial engineer instead of an automotive engineer. We had a few M-B's prior to that and they were truly superior in most respects. A little over-engineered in a few places, but generally really great cars.

I find it really interesting that Toyota, which is on the cusp of becoming the world's #1 car maker is run by a guy with an engineering background. Ask a GM executive what GM makes and they'll tell you "money".

Re: Karl's statement about consumer maintenance: The EPA was VERY resistant to that for the same reason. They do not trust the consumer to lift a finger to keep the environment clean. Makes you wonder; I thought the great majority wanted cleaner air. We've got a huge goverment agency to give it to us because the people wanted it. Yet the agency itself knows nobody will do the least little thing to promote it. Hmmm.

 

[67hat34c]

so what does a urea factory look like, bunch of guys drinking beer with cathiter hooked up?

 

[jim rosenthal]

No, you're thinking of urine, which is not the same thing...

The youngest Mercedes I have is a 1985 300CD- the last year that the iron-block 5cyl diesel was sold here. While they are not maintenance-free (nothing is) they are very reliable solid cars that will go incredible distances if taken proper care of. Note that I do not have any MB cars made after 1985. There's no question that their quality has slipped badly- a friend of mine who has been an MB service manager for decades tells me that better than fifty percent of the work in their shop is warranty. That is outrageous.

My daily driver is a Toyota truck. Just like a Timex- takes a licking and keeps on ticking. I find it hilarious that people think of Toyota as a Japanese company- they sell more cars here than anywhere else and they will end up building more cars here as well. They are successful because they build cars that run well, last a long time, and are for the most part easy to service. Like he said, the company is run by engineers. I don't think there's any secret formula for their success- but they actually DO what lots of other carmakers just talk about doing.

Finally, I thought the clathrate was the discount that the clath getth if they all get together and akth for a group rate......

 

[67hat34c]

thanks Dr. Jim, it threw me off as I read the following thinking it was related:

The individual atoms that make up a urea molecule come from carbon dioxide, water, aspartate and ammonia in a metabolic pathway known as the urea cycle, an anabolic process. This expenditure of energy is necessary because ammonia, a common metabolic waste product, is toxic and must be neutralized. Urea production occurs in the liver and is under the regulatory control of N-acetylglutamate.

Most organisms have to deal with the excretion of nitrogen waste originating from protein and amino acid catabolism. In aquatic organisms the most common form of nitrogen waste is ammonia, while land-dwelling organisms developed ways to convert the toxic ammonia to either urea or uric acid. Generally, birds and saurian reptiles excrete uric acid, while the remaining species, including mammals, excrete urea. Remarkably, tadpoles excrete ammonia, and shift to urea production during metamorphosis. In veterinary medicine, Dalmatian breeds of dogs are different in that they excrete urea in the form of uric acid in the urine rather than in the urea form. This is due to a defect in one of the genes controlling expression of the conversion enzymes in the Urea cycle.

The urea is formed in the livers of mammals in a cyclic pathway, from the break down of ammonia, (a metabolic waste), which was initially named the Krebs-Henseleit cycle after its discoverers, and later became known simply as the urea cycle. This cycle was partially deduced by Krebs & Henseleit in 1932 and was clarified in the 1940s as the roles of citrulline and argininosuccinate as intermediates were understood

 

[Freebird]

thanks Dr. Jim, it threw me off as I read the following thinking it was related:

The individual atoms that make up a urea molecule come from carbon dioxide, water, aspartate and ammonia in a metabolic pathway known as the urea cycle, an anabolic process. This expenditure of energy is necessary because ammonia, a common metabolic waste product, is toxic and must be neutralized. Urea production occurs in the liver and is under the regulatory control of N-acetylglutamate.

Most organisms have to deal with the excretion of nitrogen waste originating from protein and amino acid catabolism. In aquatic organisms the most common form of nitrogen waste is ammonia, while land-dwelling organisms developed ways to convert the toxic ammonia to either urea or uric acid. Generally, birds and saurian reptiles excrete uric acid, while the remaining species, including mammals, excrete urea. Remarkably, tadpoles excrete ammonia, and shift to urea production during metamorphosis. In veterinary medicine, Dalmatian breeds of dogs are different in that they excrete urea in the form of uric acid in the urine rather than in the urea form. This is due to a defect in one of the genes controlling expression of the conversion enzymes in the Urea cycle.

The urea is formed in the livers of mammals in a cyclic pathway, from the break down of ammonia, (a metabolic waste), which was initially named the Krebs-Henseleit cycle after its discoverers, and later became known simply as the urea cycle. This cycle was partially deduced by Krebs & Henseleit in 1932 and was clarified in the 1940s as the roles of citrulline and argininosuccinate as intermediates were understood

Dang Steve, now I know why you had such a hard time cooking wings around Christmas. Good Lord son, did you Google something to come up with all that stuff?

I took lost of stuff like that in college, but all I can remember is pie are round, cornbread are square. Oh yeah, when I was going through my M-B daze, mine were gas. I was not quite policitically correct enough to order an SL with a diesel engine.