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Discussion Starter #1
Wow, so i've been watching the other threads, and now I get hit with a similar problem. My cpl858 has been trucking along, but when we had the cold snap down here in SC, she started smoking heavily at both idle (white smoke) not much load (gray haze), and full load (black smoke).

Now that it's nice outside - 60ish, she's still smoking. At idle, you can be choked by the white smoke (unburned fuel). I've tried running off a jerry can to see if it was my fuel (same smoke), and tried changing the filter (same smoke). I also just changed the lift pump (it ran fine for a few days on that pump before things got cold).

I'm also thinking that since i was running off the jerry can, with new fuel line, that it's not air in the system.

The pump is at near-stock settings, maybe 3/4 to 1 turn on the FP screw.

I'm in a real pickle, folks. Suggestions?
 

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Maybe a boost leak....I know when I had a leaky intercooler boot I had tons of white smoke and low power. Might want to check all air connections between turbo and intake. Sounds air related to me..
 

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Discussion Starter #3
I'll go ahead and say that I'm low on power too, I seem to be really putting the pedal down, which just adds to the gray/black smoke... two weeks ago the exhaust would have cleaned up with the boost, but its not at all now.

I'll also say that I added about 2 quarts of used, filtered 15w40 to 30 gallons of fuel a tank ago, which i've burned out and refueled since...
 

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Discussion Starter #4
So i checked the play in the turbo this morning... wow, that wasn't good. I've got maybe .5mm of radial play, and 1-1.5mm of axial play... i'm guessing that would affect my boost in a way that veggie80 was indicating. What should the play be?

I'm really wondering if oil was caked in the turbo housing, making the turbo feel tight, and the cold snap got my oil pressure high enough (>75lbs) that it blew out that caked on crap, so now it's feeling nice and loose... but then again, she's not 'barking' anymore, so that could also have been the culprit. Does it sounds like I'm going down the right path with diagnosing this as a turbo issue?
 

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Your white smoke is going to be oil, your turbo may have enough slack in the shaft that oil is getting passed it and getting into the exhaust housing, which at around 350-400 degrees at idle will produce a nice white haze.
 

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So i checked the play in the turbo this morning... wow, that wasn't good. I've got maybe .5mm of radial play, and 1-1.5mm of axial play... i'm guessing that would affect my boost in a way that veggie80 was indicating. What should the play be?

I'm really wondering if oil was caked in the turbo housing, making the turbo feel tight, and the cold snap got my oil pressure high enough (>75lbs) that it blew out that caked on crap, so now it's feeling nice and loose... but then again, she's not 'barking' anymore, so that could also have been the culprit. Does it sounds like I'm going down the right path with diagnosing this as a turbo issue?
Axial play limit is .127mm, Radial is .4572mm. (If the specs I found in this thread are right: http://4btswaps.com/forum/showthread.php?t=529 Given as Axial .001-.005" and Radial .012-.018").
 

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Other thing to look for would be valve seals, they can cause a headache too. With the turbo off, look into the exhaust manifold to see if there is oil residue in there. If its an iffy, re route your oil lines to the turbo and run the engine a bit. Watch the exhaust manifold to see if your getting any oil out of it. If that doesnt do it, time to fire up the compression gauge.
 

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Discussion Starter #8
Would the valve seals give up 'all the sudden'? It just seems like things went from all good to 'bad' all at once, on the day that it got to the teens outside. I'm still leaning on the oil pressure getting to 80-85 that day, and blowing out the 'gunk' that was holding the turbo shaft within spec... or that the barking of the turbo did it.

Now that I think about it, i've checked the turbo before a couple of months ago, and it was 'tight' when the engine was cold. When I checked this morning, it was loose to the touch, and turned easily, a marked change.
 

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I dont think the oil pressure blew out coking. Coking is very hard about like coal or something. However, it does sound like you have a good deal of play. It could be that you just lost the rear carbon seal and it caused it to start dumping oil in the exhaust. If this went it could also cause the turbo to be lazy.
 

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I've got those same symptoms and have my turbo apart right now pending rebuild parts. Hope it fixes it. I'll post back with results.
 

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Discussion Starter #11
Sounds good, I'll keep an eye on the oil level (this is my DD and i can't have it down for long). It looks like what I'll do is see if I can find a H1C in the proper configuration that's good, and swap it out with mine. Then I can take mine down for a rebuild.

If the coking doesn't blow out, then it had to be the barking that killed the turbo.
 

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Sounds good, I'll keep an eye on the oil level (this is my DD and i can't have it down for long). It looks like what I'll do is see if I can find a H1C in the proper configuration that's good, and swap it out with mine. Then I can take mine down for a rebuild.

If the coking doesn't blow out, then it had to be the barking that killed the turbo.
Ahhhh....are you the one that posted about surge? If so, you have learned what it will do. Luckily, the compressor wheel stayed together and you only lost the bearings and seals. It might have had a problem already if it was the factory turbo and was surging.
 

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You can also check to make sure the crankcase vent tube is not clogged or kinked..That will also make oil come from all seals if the cranckcase pressures get to high..Got any other oil leaks?
 

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Discussion Starter #14
Nope, none at all, when I put the motor in, I replaced the valve cover gaskets, pan gasket, front and rear main seal, and the fuel pump seal when I replaced that a few weeks ago, she's nice and dry all over.

Yes, I was the one that posted about the surge... now we know that 'chattering' leads to 'turbo death'.
 

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Yes, I was the one that posted about the surge... now we know that 'chattering' leads to 'turbo death'.
It will kill them about as fast as no oil if it is bad enough. You still got lucky because they compressor can explode.
 

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Finally got my rig back together a little while ago. The rebuild seems to have taken care of the smoking issue and it runs much better. It would, however, be impossible at this point to say to what degree the rebuild affected the performance increase, as I swapped to a 12cm exhaust housing in the process of all this. Put a 366 spring in it while it was in the shop too. Just like having a different truck.
 

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how is the driving different? what about mileage? I'm trying to figure out if how i want to do my performance upgrades.
 

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how is the driving different? what about mileage? I'm trying to figure out if how i want to do my performance upgrades.
Going to a smaller exhaust housing should be first on everyone's list.
 
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