I'm actually not sure. There's probably some gear head on this thread that knows more about diesel engines than I do.
I like my diesels too...
And believe me, the "other 99% of truck owners" hate the coal rollers too. They're destroying their engines for the sake of making some idiotic point and drawing an awful lot of very unwelcome attention to diesel trucks that have largely been left alone...
The first thing to point out is that there's a difference between "rolling coal" and the moderate haze that a lot of diesels do under acceleration (either if you're not gentle with the throttle, or just when an older engine is making good power). If it's a brownish haze, that's just what some older engines do, and if it rapidly clears up substantially, the fuel flow just outran the turbo spooling up. Plenty of older engines had mechanical fuel controls and would just dump fuel in if you didn't feed throttle in gently. Even the late 90s/early 2000s electronic systems were prone to this. I can get my engine to put out a decent haze if I'm not gentle with the throttle. I try not to, but sometimes if you're heavy with a trailer, and turning onto a high speed road, there's just no real other option than to put your boot in it and let the engine sort it out as boost comes up (I have some leaking up-pipes to the turbo and can't really get past 20psi, would like to change a few things out at some point and get a couple more pounds when pulling hard).
"Rolling coal" is the sort of jet black column of smoke that hazes out the area, and that's just a deliberate dumping of fuel into the cylinders. Diesel is an oil, but it's really not a good lubricating oil, so it ends up washing down the cylinder walls (the engine oil remains up in the hatching on the cylinder wall to lubricate the rings on the next upstroke, and the diesel washes this out so it tends to wear the rings and cylinder really badly). A diesel is a lean burn engine - they run with the air supply "wide open" and control power by fuel delivery. As you head towards maximum power output, you start approaching the stoichiometric mixture, but on most diesels, you're limited before that point by exhaust gas temperature. At least if you care about your engine and turbo. As you continue adding fuel, you end up on the rich side, and there's no good reason to run a diesel over there unless you're doing something like a tractor pull, where you want every bit of air you can cram into the engine burned, and need to cool combustion with excess fuel. The result is a column of black smoke, and tractor pull engines running up there are not exactly long lived... they're closer to a drag engine that's rebuilt constantly.
https://www.youtube.com/watch?v=57zTeSoOLA0 if you're not familiar.
As far as I can tell, it started from a "Engines that make lots of power blow black smoke, therefore if I make my engine blow black smoke, it's making a lot of power" sort of "correlation does not equal causation" logical flaw. You can make most diesels belch black smoke by covering most of the air filter with a grocery bag or otherwise massively restricting the air intake. Doesn't mean they're making power.
If they're actually putting out a column of black smoke, and not just some brown haze, get the license plate, and see if you can find your local emissions "polluting vehicle reporting" contact. It's not hard to get such a truck back into an emissions compliant form, but it's annoying, and hopefully after a few times people will stop bothering.
Topic: Electric Cars: Can they finally become popular in the United States? (Read 537410 times)
