SpoolnByYou

sup guys,
i recently rebuilt my motor and have a practically brand new turbo on the motor. just hit 500 on the motor,but still havent dogged the motor at all. Car never smoked or anything before,but just recently when the car sits for a couple hours,then i start it up it will slightly to moderatly smoke at idle. and its blue smoke. but after a drive,the car stops smoking,even at idle. im pretty sure its not the motor,compression is good,and like i said i just rebuilt it. is it normal for some turbos to smoke at idle when first started? i have a garrett turbo. ive heard that garrett turbos use a "piston ring" type seal on the exhaust end of the shaft. this "piston ring" seal works with your oil pressure. as oil pressure hits the ring,it "pushes" to outward,creating a better seal. so at idle,or low shaft speed,the ring could "leak" oil due to not having that pressure to ensure the seal. sound true?


or what could be going on?


and just to add so no one asks,my oil feed and return are fine. no kinks dips or restrictions.

Dialectic

Yeah I had this same problem. I fixed my return line and it quit. Now recently it is doing it again and just like your problem only at idle, and after driving for a little while it goes away. I believe it might be the seals and oil isn't getting back to the pan and gets burned up through the exhaust. As far as the "piston ring" type seal, I had no idea how the seals function until you said something about it which does make sense, since the pressure wouldn't be there. Also where on the oil pan in your return line mounted?

92vx-t

What size return line are you using? I just recently got my setup finished and my is burning hella oil, we put a restrictor in the oil inlet fitting, i fixed my return line and it cleared up some. But i think i might need to be bigger because im using a vx mani and i had to use to 90-degree fittings.

SpoolnByYou

my oil return fitting is right at the top of the oil pan,to the center.

my return line,im not sure on what size it is. i guess standard return line size,i think 10ans if that sounds right. to try to better explain it,its probably the same,if not little more in diameter as your pinky finger.and my oil feed line is a re-enforced rubber hose. size whise,id say a little smaller in diameter then your pinky finger. but i do have an oil restrictor,i think 1/8th npt. so even though my line is bigger then most,i have a restrictor.

SpoolnByYou

any more input?

Boosted Power

I also agree. If your car is smoking at idle. It could be either your return line is not big enough or not at the right angle.
Your turbo seals could be blown also. I mean the turbo isn't boosting or anything at idle, but your oil is still flowing through the turbo.

eg crunkmonster

if u dont run an oil restrictor it could cause this problem because theres too much oil pressure which could push oil through the seals

coneheadsracing

i recommend 3an input line. I was using the reinforced hose, caused me lots of problems with smoking. I put a restirctor on it, but i did that at the turbo and the smoking was less, but i still feel even at that point you get too much pressure, cause its such a large diameter line.

To give you an idea, with that line my oil pressure was around normal, or 30-70 psi depending. When i switched down to a 3an line, my pressure never goes above 25 psi cold. Plus, no smoking Also, if you have smoking you are getting oil into the ehxuast, and it will take time for it to all clear out.

92vx-t

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by eg crunkmonster &raquo;</TD></TR><TR><TD CLASS="quote">if u dont run an oil restrictor it could cause this problem because theres too much oil pressure which could push oil through the seals</TD></TR></TABLE>

Yep it sure will, i just got my builder to put an restrictor in the oil inlet fitting. Im running an 1/8" oil inlet hose and 1/2" return hose. I was running 3/8" return hose and it wasnt draining fast enough and cause it to push thru the seals and burn out my exhaust.

SpoolnByYou

i am running an oil restrictor. my oil feed fitting is 1/8th npt.