Blue smoke on start up

[atomicglock]

Hey all,

It's getting cold here in the northeast and lately I've noticed blue smoke when I start up. The colder it is the more the smoke. A couple days ago it was in the low teens. I'm surprised the fire dept. didn't show up thinking the house was on fire. Strange thing is, I checked the oil level this morning and it was fine. So where is the blue smoke coming from if not the oil?

Howard

 

[Zookie400]

blue smoke is often thought to be burning oil that is passing the rings, wich is true, BUT....cold diesel engines will always smoke blue, and its mostly not burning oil.

diesel engines rely on extreme heat made by the compression stroke to ignite and burn the fuel. when the engine is cold, the metal sucks a lot of that extreme heat energy up, leaving you with a lukewarm combustion chamber. the cold combustion chamber doesnt effectively ignite or completely burn the diesel when it is injected, and basically the blue smoke you see is raw unburnt fuel.

some of the blue smoke is probably from oil going past the rings as well, but not a significant amount in most cases. the ring gaps open up when everything is cold, but as the engine heats up the rings expand and close the gap back to acceptable runnable tolerances. this is normal, and can probably be best seen on a high mileage cummins 855

if your blue smoke is extremely excessive, you may have a few glowplugs out, or a bad glow plug relay. the glowplugs are designed to supply the cold combustion chamber with a "glowing" red hot probe to help ignite the fuel.

 

[howardsvm]

Blue smoke and lots of it

I have the same problem it started about 15K miles ago. So I put new injectors in it and it runs better and some of the smoke went away and it idels better. But now the smoke is back. it's not warm up smoke, it looks like a fire fills the yard. When it warms up it goes away.

I also have pretty bad blow by. I am not ready to give up yet. It's only got 165K on it. I have seen these motors with 500K miles on the with no problem.

 

[atomicglock]

Thanks for the replies, guys. This is the 2nd 2000 Ford diesel I've owned. I wrecked the first one last December and bought my current one in January. I didn't have the smoke problem (with either truck) until this year. The colder it is, the worse the problem, but it does eventually clear up once the truck warms up. Also, when I come out from work after a 12 hour shift, it does not seem to smoke as bad.

Zookie: I expect black or gray smoke on start up due to unburned fuel but I've always associated blue smoke with burning oil (remember the old Chevy's that would let oil leak past the valve seals). My first thought was leakage past the fuel injector seals but the oil level is fine and with the amount of smoke I'm seeing, the oil should be low if that were the case. I replaced the glow plug rely last winter and I've not had any starting problems so far. I will admit the block heater does not seem to work as well as I've experienced in my previous truck.

I know how diesels work and, like I said, this is not my first one. This truck did not smoke like this last winter, so something has changed.

Howard

 

[Zookie400]

low compression would cause the same issue, but it would also cause a hard start or very long crank to start. you could compression test to see if maybe you have a bad cylinder or two....?

valve seals leaking could be a possibility, but after a 12 hour shift i would expect it to have enough time to drip in and fill the ports enough to smoke again. also you say the oil level is not going down.

black smoke is from oxygen deprived burnt fuel (charcoal)

try testing each glowplug individually, maybe there are a few bad ones?

 

[JLDickmon]

five bucks says it's got a couple bad glow plugs

 

[atomicglock]

try testing each glowplug individually, maybe there are a few bad ones?

Ok, I'll have to give that a try. Thanks.

Howard

 

[howardsvm]

Blue smoke

I have been studing this for awile. From what I can tell my motor has been " dusted " The blue smoke is a product of poor combustion and low conpression. I find it hard to beleave that my motor is worn out at 185K but this seems to be the case. thanks Ford for that aircleaner box!!

 

[CKyle494]

has anyone seen valves this bad off of a PSD. Reckon it is caused by the ulsd? Mine starting burning oil at a rate of 1 qt every 150-175 miles driven. Replaced the turbo because the intake was full of oil and the seal was shot between the turbo itself (blow by?) After that done it again.....what the heck? Decided to pull heads and check valves to see how far to go with rebuild. Found the valves like this, machined the heads and just decided to go ahead with rebuild (had 245000 on it). Just about to get it back today and hopefully it is right. ?But who knows just want it to go another 245000 so it falls apart.

 

[JRJ04]

The ford air box has pretty good filtration so long as make sure it is sealed well. The clamp on mine started to break so I tossed it and went with the DIY intake.

I would not think ULSD would case that problem. Its never a bad idea to start adding a qt of 2 cycle motor oil to every tank of diesel. It really helps to keep everything lubricated and running properly.