Blue smoke and oil consumption... HELP

Laine D

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So I have an 86’ 6.9 turbo. It supposedly has 185k on it. It sat for 10 years only bring ran like 4 times just to move it out of the way so they could move tractors and such. The previous owners told me that it never smoked before. Not one bit. Now, it obviously does smoke and I hate it. I drive a couple miles to school and back every week and around town. I think it uses about a quart of oil every 50 miles. What’s weird is that when I’m going down the road it doesn’t smoke. But at idle at a stop sign it will start to and then especially when I take off after idling. It’s almost like I need to clear it out. It runs really really good so it’s hard for me to think it’s the rings especially because it never smoked before. Now I’m wondering if it could be the valve stem seals? I sure hope so. Could they have cracked or something? When the truck is cold it doesn’t smoke as much, actually not really any. I think that’s because all the seals haven’t expanded because of the cold temperature? Please help somebody :( I want my truck to be happy again
 

RetiringColt

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Is there any oil accumulation in the bottom of your air box. I'm not sure where the cdr valve is on the 085 kit. The cdr would show if the rings have blow by. Or if the cdr valve is bad. I think the turbo rebuild kit runs about $50 ish. In my experience when the turbo seal goes out you get smoke when under load or acceleration. Probably worn valve guides and guide seals. Hope this helps.
I'm new here too! This is my first reply.
 

Laine D

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Is there any oil accumulation in the bottom of your air box. I'm not sure where the cdr valve is on the 085 kit. The cdr would show if the rings have blow by. Or if the cdr valve is bad. I think the turbo rebuild kit runs about $50 ish. In my experience when the turbo seal goes out you get smoke when under load or acceleration. Probably worn valve guides and guide seals. Hope this helps.
I'm new here too! This is my first reply.

Yes sir there is oil accumulation. Funny thing is that i ran it with a road draft tube and it still smoked. There is vapor and looks to be blow by but I remember the truck and it had never smoked before they parked it. I’m just a bit confused haha. There is some noise from the valves so I’m hoping it’s got something to do with the seals
 

RetiringColt

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Ok. That would make me lean towards leaking turbo seal. What condition is your air filter in? If the filter is plugged, there could be a little bit of vacuum on the intake. The diesel turbo seal aren't made to handle vacuum. Gasser turbos have double seals to overcome the pull of vacuum. The oil residue in the intake might be from gravity when the engine is off. The little bit of oil drains from the compressor housing into the air box. Ya valve guides and seals would be an expensive ordeal. But hey, a good excuse for head studs?
 

Laine D

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I like the way you think. Head studs would be cool. Now I don’t want to sound stupid but how would the turbo seal have anything to do with me using oil?
 

Thewespaul

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Ok. That would make me lean towards leaking turbo seal. What condition is your air filter in? If the filter is plugged, there could be a little bit of vacuum on the intake. The diesel turbo seal aren't made to handle vacuum. Gasser turbos have double seals to overcome the pull of vacuum. The oil residue in the intake might be from gravity when the engine is off. The little bit of oil drains from the compressor housing into the air box. Ya valve guides and seals would be an expensive ordeal. But hey, a good excuse for head studs?

There’s no difference between gas and diesel turbos in seal design. The same turbos that were added on these trucks by aftermarket kits were already in oem use by many import manufactures at the same time.
 

RetiringColt

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Thanks for the correction Thewespaul! I tried to find some info on the subject and found I was mistaken. I have a HP book on turbocharging. There is an article that states," Diesel-type turbos had no seals to protect against gasoline flowing through compressor into turbo bearings". They were referring to a carbureted draw through system. It's also dated 1962.
Lane D turbos use a seal that looks and works like a piston compression ring.
 

Laine D

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This thing is so confusing. I was driving home from school and I stood on it and it didn’t smoke any blue. There was no vapor coming from the cdr either. Then 15 minutes later the vapor started coming back and then the blue smoke. Is the cdr stuck open???
 
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