Why diesel oil turns black immediately after chang

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Hi, I have one question... Whay diesel oil turns black immediately after change.
 
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sweden
because soot is an excellent dye and there has to be very Little left to turn the new oil black. - It´s a no problem thing, get used to it.
 

JHZR2

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Yep, very little loading mass or volume percentage-wise dyes the oil very well.
 
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In layman's term: That means the oil is doing what it is supposed to do "keeping the engine clean and keep all the combustion trash floating in the oil". That is why diesel engine requires oil specifically designed for diesel engine combustion. The only way to know if your oil is good or bad is by doing oil analysis.
 
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Yeah, the soot level can be extremely low and the oil look like tar. I do 25,000 mile oil changes on my 12.7 Detroit and the oil looks black within the first 1000 miles, but the soot level at 25,000 miles is still less than 1%.
 
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I think the consensus is that EGR causes soot to get into the oil in diesels. In applications where it is possible to delete the EGR, soot loading appears to be substantially reduced. Engines with aggressive EGR designs (ie: the newer EPA-spec Tier diesels) tend to place the greatest demands on the soot suspension characteristics of motor oil. As others have stated, not a problem if both the oil and the filtering system have been appropriately engineered, and fluid maintenance done appropriately.
 
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yep. The EGR is the culprit. That is why many heavy commercial trucks are having bypass oil filters or centrifuge systems put on by owners. Soot loading is horrendous. How one can figure that feeding a motor its own feces can make things better is beyond me. If that is true, then go out tonight and have a fine meal at a 1st class restaurant, come home and when you take that next dump, grab a handful and eat it and then see if the next dump is cleaner than the first.
 
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Originally Posted By: TiredTrucker
How one can figure that feeding a motor its own feces can make things better is beyond me.
EGR results in less oxides of nitrogen being produced as a product of combustion. This is because combustion temperature spikes are reduced. I believe this was pioneered in air cooled VW engines, where such spikes could be more harmful than conventional water cooled iron engines. Incidentally rabbits and I dare say other animals eat their own feces to get full benefit from the nutrients in their diet. Ruminants also recycle their digestive systems. I don't want to be a rabbit or a cow!. Claud.
 
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There is no reason to want to reduce NOX, it comes from cylinder pressure and cylinder temperature which are directly related to cylinder filling and torque.
 
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Originally Posted By: Olas
There is no reason to want to reduce NOX, it comes from cylinder pressure and cylinder temperature which are directly related to cylinder filling and torque.
Introducing nitric acid into the atmosphere strikes me as a good reason. Claud
 
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Originally Posted By: Claud
Originally Posted By: Olas
There is no reason to want to reduce NOX, it comes from cylinder pressure and cylinder temperature which are directly related to cylinder filling and torque.
Introducing nitric acid into the atmosphere strikes me as a good reason. Claud
Then ride a bike everywhere, otherwise drop the holier-than-thou act. You drive a car, use electricity, buy stuff from multinationals, all of which are extremely damaging to the environment. A few ppm NOX with the consequence of better power, better torque and NOT having to clean carbon/soot from the inlet tract is more than worth it.
 
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Originally Posted By: Olas
Originally Posted By: Claud
Originally Posted By: Olas
There is no reason to want to reduce NOX, it comes from cylinder pressure and cylinder temperature which are directly related to cylinder filling and torque.
Introducing nitric acid into the atmosphere strikes me as a good reason. Claud
Then ride a bike everywhere, otherwise drop the holier-than-thou act. You drive a car, use electricity, buy stuff from multinationals, all of which are extremely damaging to the environment. A few ppm NOX with the consequence of better power, better torque and NOT having to clean carbon/soot from the inlet tract is more than worth it.
+1 Green intiatives are always for other folks to follow. I attended a water quality conference a short time ago and it was a bit of a chuckle to see the tree hugger bumper stickers on the SUVs in the parking lot. I'd venture a guess that purchasing goods produced in emerging markets like Mexico and China is the worst possible choice someone could make for our planet.
 
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Diesels were already well on the way to being much cleaner than ever prior to this nonsense. Better designs combined with computer controlling were allowing some very fuel efficient and clean designs. However the powers that be were still living in the naturally aspirated diesel days, and NOx was targeted first, by introducing EGR, by doing so, the already efficient motors started generating larger amounts of particulates from unburned fuel. So, then we had to introduce Diesel Particulate filters to capture the soot. If they had gone with SCR utilizing DEF fluid out of the gate instead of EGR, it might have been possible to eliminate the lion's share of the problems we have now. But even with SCR now, once these folks decide something has to be in place, it is almost impossible to get them to change their minds. The stacks on my pre-EGR, no emission control motor never have nasty soot buildup on the stacks. My 2006 Cummins ISX EGR equipped one, the soot buildup on the stacks was terrible. What changed? Just the advent of EGR. Also, the non EGR equipped motor got, and still gets, better mpg than the industry average for OTR trucks. It was a fight to get the EGR motor tolerable mpg. EGR cost an average 1-2 mpg loss on commercial class 8 OTR trucks across the board. That doesn't sound like much to the average user, but for a truck that runs 120K to 140K miles a year, we are talking about well over $10,000.00 in wasted fuel because of EGR alone. The general formula is for every 1/10th drop in average fuel economy, you lose an average of just under $1000 on that one truck in one year. And you multiply that over the 2.5 million commercial trucks in the U.S. alone and the numbers really make it hard to justify EGR. Things are coming around, and class 8 truck motors are getting some pretty good mpg now, but the emission control systems and the advanced designs to get there is adding roughly $20K - $25K to the cost of a truck. And the operational cost and down time when these systems go goofy still is hurting everyone.
 
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Originally Posted By: Olas
Originally Posted By: Claud
Originally Posted By: Olas
There is no reason to want to reduce NOX, it comes from cylinder pressure and cylinder temperature which are directly related to cylinder filling and torque.
Introducing nitric acid into the atmosphere strikes me as a good reason. Claud
Then ride a bike everywhere, otherwise drop the holier-than-thou act. You drive a car, use electricity, buy stuff from multinationals, all of which are extremely damaging to the environment. A few ppm NOX with the consequence of better power, better torque and NOT having to clean carbon/soot from the inlet tract is more than worth it.
I'm not trying to be holier than thou, maybe I should just drop litter in the street and dump waste oil down a drain because I'm too lazy to make any effort to do anything other than act in my own short term self interest. Claud.
 
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Following that line, how many solar panels are on your roof? How much wind power do you harness? How many water-butts are placed around your property? What other forms of renewable energy do you use to better the environment and reduce your own impact? How do you feel about buying commercially generated power? How much do you spend on fuel (petrol/diesel/LPG) in a year? Besides, if NOX is as bad as you claim why isn't it tested on the MOT? It seems to me that our current system is most concerned with HC and CO, which you can be failed on. In fact, emissions testing is performed on all cars made after 75 (I mean a proper test, not a visual one) and NOX isn't measured for any of them. How many successive governments, alterations to Construction & Use and changes to MOT regs have we seen over the last 40 years? More than I can count on all of my fingers and toes. If there was any concern for the impact of NOX it would be tested and charged in the way Co2 is.
 
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I think the message to take from here is not to go to either extreme.....
Originally Posted By: Olas
Following that line, how many solar panels are on your roof? How much wind power do you harness? How many water-butts are placed around your property? What other forms of renewable energy do you use to better the environment and reduce your own impact? How do you feel about buying commercially generated power? How much do you spend on fuel (petrol/diesel/LPG) in a year? Besides, if NOX is as bad as you claim why isn't it tested on the MOT? It seems to me that our current system is most concerned with HC and CO, which you can be failed on. In fact, emissions testing is performed on all cars made after 75 (I mean a proper test, not a visual one) and NOX isn't measured for any of them. How many successive governments, alterations to Construction & Use and changes to MOT regs have we seen over the last 40 years? More than I can count on all of my fingers and toes. If there was any concern for the impact of NOX it would be tested and charged in the way Co2 is.
 
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Originally Posted By: DibroTeam
Hi, I have one question... Whay diesel oil turns black immediately after change.
it is no problem, at least you know for how long you use it.
 
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Sep 2, 2010
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Louisiana
I offer that any residual oil in the engine after draining, will stain the new oil immediately once the engine runs. Don't panic.
 
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