PCV with turbo setup HELP
 

Thanks in advance guys, i have a freshly rebuilt 6.0 LS mated to a T56 in my 71 Cheyenne. Problem is that after driving it for a couple of minutes i start seeing smoke (bluish black) i assume oil, start coming from the exhaust. Im running a 78 mm turbo and noticed today that the turbo was leaking from both sides of the turbines. From what ive read im having excessive blow by or incorrectly set up pcv. What are some ways to set this up correctly or any ideas?
My current setup is : Drivers side valve cover (with pcv) hose to top of Catch can (non vented). Then from catch can to intake manifold close to throttle body.

Passengers side valve cover only has one opening and that is capped off.

My piston rings were gapped 26 top ring and second ring at 28.
Thanks again guys

Re: PCV with turbo setup HELP
 

You need filtered air in to the motor.
Put a breather where the cap is on the passenger side cover.

You might also need an adjustable pcv like this.



http://mewagner.com/?p=444

Re: PCV with turbo setup HELP
 

Geezer is right. It has to have somewhere to bring in fresh air.

Re: PCV with turbo setup HELP
 

If you are leaking through your turbo seals, especially into the exhaust, on a new turbo install, check your oil feed restrictor size and the oil drain is big enough and free of kinks.

If oil is building up in the turbo, it will push through the seals and into the exhaust.

I may be reading your post wrong, but I don't see any obvious relation between your problem and the pcv/catch can system. If you were getting oil though a pcv system in the amount required to cause the truck to burn oil out the exhaust, you would see a puddle in your intercooler/piping. This is unlikely.

Re: PCV with turbo setup HELP
 

This is a very good read: http://67-72chevytrucks.com/vboard/s...d.php?t=771227

There is some info concerning oil feed/return restrictions as well as PCV plumbing....

Re: PCV with turbo setup HELP
 

I agree with this.

Re: PCV with turbo setup HELP
 

one other thing to watch when pcv are concerned is the placement of the MAF if you are still using that. You don't want to pull in un-metered air if using the MAF. I removed mine and went SD so it doesn't have the same affect.

Re: PCV with turbo setup HELP
 

Nice! This is exactly how I have my system set up with the exception of the hose (clean side) going to turbo filter. Would having that port blocked off cause oil to leak out of my turbo?

Re: PCV with turbo setup HELP
 

I have checked for any kinks in the drain side but its a pretty big hose to kink. Nevertheless Its not kinked up. As far as checking my oil feed restriction.... how would i do that? or what would I look for? Thanks!

Re: PCV with turbo setup HELP
 

Nice! This is exactly how I have my system set up with the exception of the hose (clean side) going to turbo filter. Would having that port blocked off cause oil to leak out of my turbo?

Re: PCV with turbo setup HELP
 

you need to get fresh air from somewhere. So depending on what you mean by blocked off, if you just have the hose going to atmosphere with a filter then you should be ok if you don't have anyplace for the engine to get air that wont work. Hope I said that correct and understandable.
If I remember correctly I have mine like above but I am just pulling the air without it connected to the filter system. I will assume the way it is shown above it will create a slight vacuum under acceleration thru that hose as the air is drawn over the intake port.
Clear as mud...?
Dave

Re: PCV with turbo setup HELP
 

I have mine like this and even using this fancy adjustable PCV.

Re: PCV with turbo setup HELP
 

UPDATE: So i opened the breather i had plugged up on passengers side valve cover and left it open (for now before i connect it to the turbos air filter). Took it for a drive and did not produce boost. After 15 minutes i pulled over and checked under the hood. I found oil slightly sprayed on passengers side (the side i left open for tsting purposes). so i said to myself..."self, this is ok since it will be consumed back into the air side of the turbo." So i went for another drive and drove it more aggressive, maybe 1 or 2 pounds of boost if that. As soon as i did that i saw all that blueish black smoke again shoot from my exhaust so i drove it back. When i came to check it out I saw actual oil sprayed all over my radiator and suspension. Right where the breather tube is was a nice big pool of fresh oil so it literally squirted out! It all shot out from the breather side i left open on the passengers side valve cover. I also noticed a little pool of oil on the lip of the turbo and even inside of the blow off valve. So...... Do i have two problems? Any advice is greatly appreciated fellas.

Re: PCV with turbo setup HELP
 

You got your air flow wrong. The breather is air in. Don’t matter how you hook it up. Stand alone or pulling air from the turbo inlet. It’s still air in to the motor.
Your main problem is your rings aren’t seating.

Re: PCV with turbo setup HELP
 

Well the engine has about 200 miles. The first couple of miles were aggressive as stated in the instructions from DSS pistons. Is there any way to set them in now or any additives?

Re: PCV with turbo setup HELP
 

Manifold vacuum is highest at idle and cruise. This puts negative pressure in the crankcase. I.E. air IN.
At WOT, manifold vacuum is very low or near non-existent. At the same, WOT produces maximum crankcase blow-by pressure. I.E. air out.

While this is going on, the turbo is dumping a lot of oil into the same rocker box and they're both trying to get out.

Valve cover breather or Tube to the air cleaner, this is always a two direction path for a PCV System, depending on engine load, turbo or not

Re: PCV with turbo setup HELP
 

Understood. so its a two way street in the sense. So why does so much oil shootout when i get aggressive on it? Excuse my ignorance. This is my fisrt turbo and have never dealt with this issue before. What do you think i should do?

Re: PCV with turbo setup HELP
 

Understood. so its a two way street in the sense. So why does so much oil shootout when i get aggressive on it? Excuse my ignorance. This is my fisrt turbo and have never dealt with this issue before. What do you think i should do?

Re: PCV with turbo setup HELP
 

Does a baffle in the valve cover help with this reverse flow?
I would think so.
Shouldn’t see any oil splatter under normal cruise.
Maybe a leak down test is needed.

Check for a baffle in your valve cover.