Just got back from my trip to see my kid for his birthday and it ran great. Plugged it in last nite, started easier of course, but still same amount of smoke. None the rest of the day on any start. Stayed about 10* outside all day. Stepped on it a little once on the highway to see how it was going and boost came up right away and felt fine. Smoke was normal black color. Think all is ok. Got new batteries for it today, so will put those in soon for sure.

 

Nothing like a good run!

 

From what I found out by my exhaust side leak is that if your turbo spews oil out the exhaust seal into the exhaust, it will burn white.
If it goes though the motor and burns in the chamber, it will come out blue.

When my turbo started leaking oil into the exhaust, there wasn't a touch of blue in the smoke, it would just idle white smoke and bellow white smoke when I got on the throttle, then when leftover fuel joined the mix, it would come out grey.

Unburnt diesel is white and black.
So, yeah, every time you step on it and throw a black cloud, thats unburnt fuel too. and soot. Black smoke out the pipe means not enough air in the chamber, or not hot enough EGT's to burn off everything in the chamber. Usually a combo of both. But watching diesel tractor pulls, they will bellow black then push out nothing when the motor gets hot and the turbo spools. Never understood why diesel truck pulls never worked the same as the tractors. *shrugs*
Thats the way I understand black smoke anyways.

Other reading has lead me to agree with others that bigger injectors equal smoke at cold startup. Even with good glow plugs. Fresh glow plugs, gpr and rebuilt injectors and my truck STILL smoked.
Mine does not after being plugged in though.

 

There is some oil in the upper part of the cylinder. Colder the oil is thicker and the scrapper may not be getting all the oil. The film could be burning off less efficiently then when its warm.

 

X2 to above post

 

I was trying to say that, Thanks!

 

That makes sense, but why does it only do it on some cold starts and not all of them?

So guys using synthetic oils shouldn't have this issue?

 

Well, its not just oil, its fuel too.
Until the motor gets hot, the excess fuel is white.
The excess oil he is talking about gives it the blue tint.

I didn't get any today. I had grey/white.
Oil was 18°F

 

Your welcome. Mine had it alot on my idi. The stroke I havent seen any yet. But the coldest so far here has been 18 which was this morning.

 

mine is doing the same thing, I never noticed it at all when it was warm or even semi cold,, Last couple of mornning its been down to 15 and ive noticed blue tint to the smoke that comes out of mine,,I have a 94.5 with 135,000 miles,, After work i had my buddy look at it when i got in truck, he said he noticed it when i started but he not to worrry about it,, Well hes got a 91 cummins and walked over to his truck, Well he started his up and just some black smoke came out like a puff, Hes got around 400.000 miles on his,, Hope its nothing i need to worry about.. The guy that i bought it from said he put new seals in it for the injectors couple years ago.. My father inlaw which has a ford 2001 excursion diesel said his does when cold, nothing to worry, not sure what to think

 

Our old 6.9 idi would smoke aweful blue when cold. That thing went well over 600k miles before it turned a main bearing.

 

i imagine them were hard miles too!

 

i get bluish smoke about 15 seconds after starting, after she sits about 3+ hours. It lasts for about 20 seconds after driving. Noticed my mpg is low during this time as well. So i tried flooring the gas pedal real quick and blow it out. Do this twice and it's gone quick and my mpg goes back to 11.2.
I have 40" tires on a 12" lift. Motor was rebuilt about 4,000 miles ago. Had it deleted and studded. It started doing this after I got it back. So i took it back, they tore it down. Saw nothing but 3 bad injectors that they just replaced.
Truck runs great. Has all the power. I see nothing abnormal. I live in southern Alabama so cold weather isn't it either.

 

deleting a 6.0, best idea i have heard all day

 

Still doesn't fix half of their problems...