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Discussion Starter · #1 ·
Hey guys (girls...), I have posted a few times already and from those results I am all the wiser. So for that, I give much thanks! Sadly, life in the turbo world just doesn't seem to be smooth sailing. Haha! About 2 months ago I hit a local AutoCross here where I live and ran the car really hard. As a result, some smoke began to work its way through my hood and obviously drew some concern. Well it turns out it was coming from the oil return hose - it was smoking where small beads of oil were seeping through the braided exterior and rising up in a white smoke. This was right near the circular clamp that fastened the hose to the rear of the turbo, just in front of the exhaust side of the turbo. As a result of this I lost some oil, but soon changed it all and had not seen any smoke like that for a while.
Until today. While I was at the light I noticed white smoke flowing out of the front grill. It wasn't anywhere near as bad as the first time, but still... this can't be good? I got home and checked it out and just as I suspected, it was originating from the same location - the return hose.
Now this might be a really freakin' dumb question... but is this normal? I mean, is this something that I will just have to learn to live with, or could it be that after only 7 months of having the turbo on it has gone bad in this spot? And if I DO need to replace the hose, is it something that the average Joe can do, or should I just take it back to the shop who turbo-ed my car? Anyway, everyone has been extremely helpful thus far, so I thought I would ask and see what advice I got. Thanks!
 

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Doesn't sound like something you should have to learn to live with. Sounds either a faulty hose, wrong size hose, both, or the oil is getting way too hot. The last of which could be caused by a few different things. I will let those who actually own turbo cars chime in though. Hopefully for your sake its just one of the first three.

Did you say its coming from near the clamp/hose fitting? Ahh, yes you did. In that case I would definitely say it's a bad hose or hose fitting... Try a better quality hose/hose fitting, run it hard and see if you can reproduce the smoke. Just run it normal some first before running hard to make sure the new hose/hose fitting isn't also a failure or complete failure which could cause more serious damage to the turbo or engine.
 

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^agreed.

It could be numerous things, but if it is coming from the clamp on the hose, it is probably a faulty clamp/hose/fitting.

Also, is the return line running straight down without any restrictions and entering the top of the oil pan (at the supplied boss)? Restrictions in the line and or too small of a line could also cause a backup, which could lead to turbo failure and other problems. Pictures of your setup would be helpful too.
 

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Discussion Starter · #4 ·
Here some pix that I just snapped. The oil return line is pointed down, as you guys said. As for the bottom portion... well, this I will have to look at. Just as a side note: it only seems to smoke when I touch high, positive boost. So it might as you said and have something to do with the oil getting too hot. These pix aren't the greatest. but they might give some impression as to where the hose is located and what its size is. If it comes down to simply needing to make a replacement, should I have a shop do it, or can I do this sort of thing myself? I know that this is a very relative question, but I mean is this something that is simple, or should I in no way mess with it? If it's easy stuff, what type of hose should I get to ensure better quality? What type of clamp? Is there anything I should know ahead of time - like is there going to be any oil that needs to be drained first...?
 

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Happened to me, feel for any play/movement. If there is well tighten it, but tighten it regardlessly.
 

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Another thought: I see that you have a "custom turbo kit." Did you use a hose that will withstand the heat of the turbo? Hopefully you didn't just use any old rubber hose. If you did use a regular hose, it most likely is melting and leaking oil through the stainless mesh.

Edit: On second thought, I would just redo the whole oil return if I were you. It wouldnt be expensive at all, and would give you piece of mind that it shouldnt leak again. I would buy a new flange gasket and hose and just re-run it.

I'm assuming you have a flange like this if you just have a hose clamp on it like that?
 

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Or convert it to a AN-10 flange. Leaks have less of a chance of happening when using AN fittings. At least in my experience.
 

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Or convert it to a AN-10 flange. Leaks have less of a chance of happening when using AN fittings. At least in my experience.
I agree with this... definitely get away from the "hose clamp" and go to an actual "fitting" on both ends...
 

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Lots of good suggestions here. If you replaced the clamp and it happened again then it might be a good starting point to replace the hole return line. It could be a faulty fitting to a bad line.
 

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Discussion Starter · #10 ·
Interesting that there is mention of tightening that clamp. After the AutoCross run when it first started smoking, I took it to a shop to figure out what was wrong and it turned out the clamp was loose quite a bit. We tightened it and no smoke for a while. I guess it could be loose again (Ummm, didn't think to check that:oops: ). AND, it only seems to smoke up after I have run the car hard and hit positive boost - most likely due to getting things hot. As for the hose... Bro, I wouldn't know if it is a good quality hose or not. Yes, it is a custom kit, but I didn't do the job myself. Is there anyway I can tell what the quality is? And can I get a little more info on this AN clamp that was mentioned? Someting else... I looked this morning in better light and noticed what looks like burning, or scorched darkness, on the side of the hose closest to the exhaust side of the turbo. I mean, the freakin' hose is right up against that part of the turbo. Should it be that close??
 

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The return line sits really close to the turbo. BUT...it should not be touching any part of the turbo and make sure it's not touching the turbo manifold. That could burn a hole or cause a crack in the hose which will lead to a leak.
 

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Interesting that there is mention of tightening that clamp. After the AutoCross run when it first started smoking, I took it to a shop to figure out what was wrong and it turned out the clamp was loose quite a bit. We tightened it and no smoke for a while. I guess it could be loose again (Ummm, didn't think to check that:oops: ). AND, it only seems to smoke up after I have run the car hard and hit positive boost - most likely due to getting things hot. As for the hose... Bro, I wouldn't know if it is a good quality hose or not. Yes, it is a custom kit, but I didn't do the job myself. Is there anyway I can tell what the quality is? And can I get a little more info on this AN clamp that was mentioned? Someting else... I looked this morning in better light and noticed what looks like burning, or scorched darkness, on the side of the hose closest to the exhaust side of the turbo. I mean, the freakin' hose is right up against that part of the turbo. Should it be that close??
AN fittings aren't clamps. They're flare fittings that look like so:



Your oil return line should not be touching the manifold or exhaust housing. If it's extremely close you may need to clock the turbo to gain a little more clearance.
 

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Long ago and buddy of mine had the same issue, this is how we fixed it: We took off the fittings, found them to be stripped causing the bad seal, put on new fittings and locktighted it with the red stuff, 25 minutes later, presto ...no more smoke. Hope this helps
 
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