Turbo smoking
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From: Home town Clive,IA current town FORT BENNING GEORGIA
Turbo smoking Hey gys,
Currently went to my tune session in KC last weekend and started the car and it began smoking like a freight train. The car set up is currently a -4 feed with a -10 return. It originally had a *90 degree -10 coming off the turbo, but that got swapped out for a *45....It still smoked.
So I figured it was the turbo, I called CRT turbo and found out it very well could have been from "improper storage". Sent the turbo of Tuesday and it was received Wednesday. Chris@CRT pulled it apart and told me there was nothing wrong with the turbo and even swapped the bearings and seals for me anyways.
Got it back today at 8am, put it on the car and for about 15 seconds it was fine then it started slowly smoking. Tried jacking the car up to give it more of a slope into the drain and it still smoked...
I went off and purchased a scavenger pump for it, well we took that put it on along side with a restrictor in the feed line.....STILL SMOKED
1) Has anyone had this problem before? if so what have you done?
2) I don't want to hurt the turbo, but I was told to let the car possible run for a while and let it burn of the excess oil, could that damage my turbo?
3) its a gt47-88 so its a midframe turbo, I put a .082 pill in it is that good enough?
Currently went to my tune session in KC last weekend and started the car and it began smoking like a freight train. The car set up is currently a -4 feed with a -10 return. It originally had a *90 degree -10 coming off the turbo, but that got swapped out for a *45....It still smoked.
So I figured it was the turbo, I called CRT turbo and found out it very well could have been from "improper storage". Sent the turbo of Tuesday and it was received Wednesday. Chris@CRT pulled it apart and told me there was nothing wrong with the turbo and even swapped the bearings and seals for me anyways.
Got it back today at 8am, put it on the car and for about 15 seconds it was fine then it started slowly smoking. Tried jacking the car up to give it more of a slope into the drain and it still smoked...
I went off and purchased a scavenger pump for it, well we took that put it on along side with a restrictor in the feed line.....STILL SMOKED
1) Has anyone had this problem before? if so what have you done?
2) I don't want to hurt the turbo, but I was told to let the car possible run for a while and let it burn of the excess oil, could that damage my turbo?
3) its a gt47-88 so its a midframe turbo, I put a .082 pill in it is that good enough?
1) Yes. Put a -12 drain on it and .060 restrictor. I still get a puff after a hard run but no more freight train. Running a C5R ported HV pump and -4 feed.
2) I doubt it. Oil hangs around forever.
3) Ask Chris.
There's probably a bunch of residual oil in the exhaust that's burning out, it's going to smoke for a little while as that burns out.
2) I doubt it. Oil hangs around forever.
3) Ask Chris.
There's probably a bunch of residual oil in the exhaust that's burning out, it's going to smoke for a little while as that burns out.
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I've had a some what similar issue with my tc7875.....mine was the breather tank was being filled with oil on a all out 1/4 pull. When It got full the blow by pressure couldn't escape and I'm guessing it backed the oil up in the return line.
I'd shut the car off after a run and on restart a smoke screen would come out the exhaust for maybe 10 sec. Fixed my issue with the breather can siphoning oil up and it has never happened again.
I'd shut the car off after a run and on restart a smoke screen would come out the exhaust for maybe 10 sec. Fixed my issue with the breather can siphoning oil up and it has never happened again.
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From: Norn Iron
Only a few things will cause smoking due to oil passing either compressor or turbine.
Excessive oil flow/pressure to the turbo. more common with ball bearing turbos which require a restrictor.
Excessive crankcase pressure preventing oil draining via the return
Restrictive or poorly designed return.
Turbo mounted at an improper angle...it should be level with oil in the top and out then bottom. A small angle might be ok, but only a small.
So the OP...you had smoking issues on the turbo and it had no restrictor at all ?
You've tried it with 82thou, is it improved ?
It may take some time for the original oil to burn off and clear.
Excessive oil flow/pressure to the turbo. more common with ball bearing turbos which require a restrictor.
Excessive crankcase pressure preventing oil draining via the return
Restrictive or poorly designed return.
Turbo mounted at an improper angle...it should be level with oil in the top and out then bottom. A small angle might be ok, but only a small.
So the OP...you had smoking issues on the turbo and it had no restrictor at all ?
You've tried it with 82thou, is it improved ?
It may take some time for the original oil to burn off and clear.
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My baffle was drilled out inside the valve cover so the fitting that was in the valve cover was wide open. Nothing was there to stop the oil from going airborn and into the line. Basically blew oil like a **** into the breather can and filled it up quickly.
That then made it so all my blow by gases had no where to go quickly and would back my oil drain from the turbo up and leak a little past the seals.
I was just stating once I eliminated that it never smokes at all.
I just plugged the holes in the valve cover baffle that were previously drilled and all is good now.
That then made it so all my blow by gases had no where to go quickly and would back my oil drain from the turbo up and leak a little past the seals.
I was just stating once I eliminated that it never smokes at all.
I just plugged the holes in the valve cover baffle that were previously drilled and all is good now.
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From: KS
You can't just throw .xxx" size restrictor in and think its good. I hooked an oil pressure gauge up in line with my turbo and feed line. Each motor and turbo are going to be different for what restrictor they require. Mine was seeing over 85 psi before I restricted them. An .078" restrictor got me lower and I kept going smaller in size until I had the correct oil pressure to control smoke but not starve the turbo. Turbonetics told me 20-55 psi. Your turbo does not see the same pressure your engine does. At least mine didn't.
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From: Norn Iron
Exactly. I have two turbos fed by -6 lines each, albeit with a -4 stepdown at each turbo itself.
zero smoking problems.
Why would I want to restrict an oil supply to a turbo that was designed to have a high amount of flow through it ?
zero smoking problems.
Why would I want to restrict an oil supply to a turbo that was designed to have a high amount of flow through it ?
Unrelated question here. Have you ever seen a single 4an line T'd to feed two turbos?
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From: Norn Iron
I probably have....not that I can recall anything specific though.
If they were BB turbos there would be no problem.
Journal Bearing...I'd have concerns unless they were tiny turbos.
I was told in no uncertain terms not to offer any restriction at all to my BW turbos.
BW make the oil feed inlet large for a reason, because they need a lot of flow. Oil not only lubricates, but helps cool the core too so flow is important.
I was told no less than 1/4" to each turbo. Strictly speaking if you take hose ID's and actual fitting ID's I am smaller than that because a -4 fitting is more like 3/16" ID actual, even if the hose itself may be 1/4" ID
So I took -8 from the filter housing, thru a check valve then split to 2 x -6 hoses, one to each turbo. With a -4 stepdown right at the turbo.
If the -4 ever was too little it was an easy change for more flow as the feed hoses were always larger.
I probably have....not that I can recall anything specific though. If they were BB turbos there would be no problem. Journal Bearing...I'd have concerns unless they were tiny turbos. I was told in no uncertain terms not to offer any restriction at all to my BW turbos. BW make the oil feed inlet large for a reason, because they need a lot of flow. Oil not only lubricates, but helps cool the core too so flow is important. I was told no less than 1/4" to each turbo. Strictly speaking if you take hose ID's and actual fitting ID's I am smaller than that because a -4 fitting is more like 3/16" ID actual, even if the hose itself may be 1/4" ID So I took -8 from the filter housing, thru a check valve then split to 2 x -6 hoses, one to each turbo. With a -4 stepdown right at the turbo. If the -4 ever was too little it was an easy change for more flow as the feed hoses were always larger.
I wonder if the high volume oil pumps vs. standard oil pumps is causing the issue. I have a ported, high volume oil pump and went through all kinds of turbo smoking issues in teh beginning with twin 70mm turbos. Initial set up and problem as follows -
Twin T4 70MM Turbonetics Journal Bearing Turbos.
Twin -4 Feed lines Unrestricted
No Crank Case Ventillation
-12 Returns straight clean shot
1) Above smoked like a pig
Changed to -8 Breathers
2) Above smoked slightly
Changed to -12 Breathers
3) Smoke at idle nearly gone, smoke after hard run present
Changed to vibrant -4 .060 restrictors
4) Zero issues now.
Twin T4 70MM Turbonetics Journal Bearing Turbos.
Twin -4 Feed lines Unrestricted
No Crank Case Ventillation
-12 Returns straight clean shot
1) Above smoked like a pig
Changed to -8 Breathers
2) Above smoked slightly
Changed to -12 Breathers
3) Smoke at idle nearly gone, smoke after hard run present
Changed to vibrant -4 .060 restrictors
4) Zero issues now.
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From: Norn Iron
My pump is a melling HV pump, although I retained the softer spring. Typically oil pressure is strangely low though, 40-60psi range, less when very warm
Havent had a chance to monitor oil temps in a harsh environment yet, I suspect they may be getting quite high though.
Short duration and road use oil temps are never a concern though
Havent had a chance to monitor oil temps in a harsh environment yet, I suspect they may be getting quite high though.
Short duration and road use oil temps are never a concern though
And I would imagine you would void most warranties doing so. Your doing nothing more than patching the real issue which is probably inadequate CCV or poor drainage. Correct me if I'm wrong but do the turbo manufacturers you use suggest using a restrictor in their JB turbos? If not than why would you?
Last edited by oscs; Sep 10, 2014 at 04:24 PM.
I get a lot of people in the shop asking about similar issues.
Before you restrict any turbo...ensure that the oil drain is correct sizing(T4 turbos-10 at least- T6 turbos -12 at least). Once your sizing is good...then you need to look at the drain line itself. It needs to flow like how a water slide would.... no high spots...all smooth shot from turbo into pan or return area. If all of those stars align,...and you have a smoking turbo...then I would look POSSIBLY into a restrictor.
Before you restrict any turbo...ensure that the oil drain is correct sizing(T4 turbos-10 at least- T6 turbos -12 at least). Once your sizing is good...then you need to look at the drain line itself. It needs to flow like how a water slide would.... no high spots...all smooth shot from turbo into pan or return area. If all of those stars align,...and you have a smoking turbo...then I would look POSSIBLY into a restrictor.