Bad turbo?

c5fourj

Occasionally moving quick
Dec 20, 2014
307
3
18
Brighton, CO
So over the summer i swapped in a s366sxe. Now that it is getting cold, when i start and run it up to about 95-100 degrees in the collant, it is dumping a fair amount of blue smoke. Once slightly warmed, past about 100 degree in the collant, there is absolutely no smoke. Nothing sounds or feels wrong to my ability to tell. It has never done this before. Should i assume the turbo seals are bad?
 

DAVe3283

Heavy & Slow
Sep 3, 2009
3,729
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Boise, ID, USA
What did you have before? The stock turbo? How does this turbo kit source the oil for the turbo? Cam bearing (like the stock turbo) or a block plug? Does it have a restrictor?

The S300 frame turbos need an oil restrictor or they can push oil past the seals when oil pressure is high, such as on a cold start. Yours could be pushing oil on a cold start, then when the truck starts warming up, it starts burning the oil out of the turbo.
 

Burn Down

Hotrodder
Sep 14, 2008
7,092
28
48
Boise Idaho
I’d pull the down pipe loose from the turbo and verify that is where the oil is coming from. And as Dave mentioned some turbos need a restrictor to keep from pushing oil. I had issues in Alaska with 400 frame turbos also.
 

c5fourj

Occasionally moving quick
Dec 20, 2014
307
3
18
Brighton, CO
What did you have before? The stock turbo? How does this turbo kit source the oil for the turbo? Cam bearing (like the stock turbo) or a block plug? Does it have a restrictor?

The S300 frame turbos need an oil restrictor or they can push oil past the seals when oil pressure is high, such as on a cold start. Yours could be pushing oil on a cold start, then when the truck starts warming up, it starts burning the oil out of the turbo.

That is exactly what i was thinking with the oil pressure so high it pushes by. It pulls oil off of the front right on the block, whatever that spot is. It was where everyone else said to pull it. I dont have a restrictor, never even knew those were a thing.
 

c5fourj

Occasionally moving quick
Dec 20, 2014
307
3
18
Brighton, CO
When you threw a restrictor on your s400 did it stop the blue smoke?
Also, what are you guys using for restrictors?
How does it not restrict when the truck is warm or am i missing something?
 

DAVe3283

Heavy & Slow
Sep 3, 2009
3,729
297
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Boise, ID, USA
You are pulling oil from a good spot, that's not the issue. My kits all came with restrictors, so I am not sure exactly what size is needed. Never thought to measure them.

The restrictor is just a small orifice in the feed line near the turbo. When the oil is cold and thick, it is under very high pressure, so it still goes through the small hole. When it is hot, it thins out, so even though the pressure is low, enough of it goes through the hole.
 

DAVe3283

Heavy & Slow
Sep 3, 2009
3,729
297
83
Boise, ID, USA
Usually the AN to NPT adapter acts as the restrictor. That one has a pretty big hole through it. You could try getting a different adapter with a smaller hole, and see if that helps.

Though I would follow Burn Down's advice first, and make sure the oil is actually coming from the turbo. Otherwise you're chasing your tail here.
 

c5fourj

Occasionally moving quick
Dec 20, 2014
307
3
18
Brighton, CO
So if i pull the downpipe, what am i looking for?... Not a mechanic.
What size do you recommend for the restrictor?
 

Burn Down

Hotrodder
Sep 14, 2008
7,092
28
48
Boise Idaho
So if i pull the downpipe, what am i looking for?... Not a mechanic.
What size do you recommend for the restrictor?

The turbine (exhaust side of the wheel will be oily and gooey) it will be a good time to make sure the bearings are still good as well. Pull the intake off so you can grab both ends of the turbo at the same time. Ck for in and out play and up and down of the shaft. Shouldn’t have much more than .001” or so in and out and you shouldn’t feel any up and down. Also grab the compressor side only and make sure it doesn’t contact the housing and spins freely while holding it as far over and turning it by hand.

If the turbo feels good then likely the seals are still ok and you need a restrictor.

You could be getting oil from the engine side as well but seeings the blue smoke started after the turbo install, I’d stick with t/s that.

As far as restrictors I just went to a -4 feed line from -6 and the s475 stopped pushing oil.
 

c5fourj

Occasionally moving quick
Dec 20, 2014
307
3
18
Brighton, CO
Ok thanks guys.:thumb: Ill buying that piece from summit and see what happens, but ill rip the intake and downpipe off first and feel around to make sure its all tight.