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Old 09-21-2010, 03:37 PM   #1
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Default PCV question

Hello, been lurking, searching, and reading for a while now but not finding any specific answers to my situation. Searching this site has been a big help to many other issues my car has had though.

I'm pushing oil past my turbo seals into the downpipe and IC piping. I thought it was to much oil so I put in a pop-rivet restrictor. I thought it was a bad drain so I put in a new one straight down from the turbo with a large line. I thought it may be a bad turbo even though it boosted fine and has no shaft play so I replaced it with a chinacharger.

I haven't really boosted the chinacharger yet but I'm still getting oil in the dp (IC pipes are clean though). I checked compression and all cylinders are 180. I'm also not getting smoke out the tailpipe but I have liquid oil in the downpipe.

I'm curious if it's the PCV but I currently have the intake side capped and the valve cover holes open to atmosphere. I've seen mixed posts where some people say you need it and some say you don't so I'm not sure of the right answer.

Any thoughts are appreciated. Car is a 1992 with a 1.6 if that matters.
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Old 09-21-2010, 03:58 PM   #2
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sounds like your pop rivet restrictor may still be way too big.
if compressor and ic pipes are oil free then its got to be coming from the turbo.

maybe the chinacharger seals are bad?
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Old 09-21-2010, 04:30 PM   #3
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Open the pvc side up, thats where all the pressure builds up more. the other side doesnt get nearly as much pressure as the pvc side.


Drill out your pvc and route it to a catch can that has a breather filter. You can also route the other port on the valve cover to the oil catch can or plug it.

If your turbo is still spitting out oil then you must have gotten VERY unlucky with your china turbo
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Old 09-21-2010, 04:37 PM   #4
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if its only in the exhaust i would have said it was the engine.

if it was in the charge piping i would have said it was the turbo.
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Old 09-21-2010, 04:44 PM   #5
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how does the manifold look? If your manifold is oiless its gotta be coming from the turbo.
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Old 09-21-2010, 05:20 PM   #6
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Thanks for the replies everyone. I bought this car from the worlds worst mechanic so pretty much everything was screwed up and I've been chasing this oil problem for a while.

I will try opening up the PCV side of things. I was going to get a new one and put in a check valve like Brain uses but I may just leave it open at first.

Since I put the chinacharger on, the charge pipe has been clean but it hasn't been boosted so I thought that may be why.
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Old 09-21-2010, 05:52 PM   #7
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is there oil in the exhaust manifold?
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Old 09-21-2010, 06:06 PM   #8
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The manifold and exhaust ports are black but it is also running very rich. This latest time when I pulled the manifold, the exhaust port for cylinder #2 seems to have some oil in it but I wasn't sure if that indicates an engine problem or it's draining back from the topmount turbo.

I'm not getting a noticable amount of smoke from the tailpipe either. When I first got the car it smoked a lot but after putting in the restrictor and rerouting the drain it quit.
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Old 09-21-2010, 06:43 PM   #9
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Quote:
Originally Posted by railz View Post
Open the pvc side up, thats where all the pressure builds up more. the other side doesnt get nearly as much pressure as the pvc side.
Lol, what?


What size rivet did you use?
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Old 09-21-2010, 06:50 PM   #10
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1/8..........had it on the old turbo and now this one.
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Old 09-22-2010, 06:23 PM   #11
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Hmmm. That should be adequate... I've got nothing for you...
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Old 09-23-2010, 08:12 PM   #12
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Thanks, it's confusing me. It could be the oil rings but I would think it would be smoking all the time. It could be the valve stem seals but I would expect a big puff at startup. I'm trying to figure out if it could be the headgasket in any way.

I'll be putting it back together in the next week with the checkvalve inline so I'll see how that goes.
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Old 09-24-2010, 11:40 AM   #13
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I'm ashamed to say I didn't catch this before. You said you are using a 1/8th inch restrictor which is .125 in decimals. You should be using around a 1/16th which is .0625 inches, half the size you have now. Some guys are running as small as .040
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Old 09-24-2010, 11:58 AM   #14
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you should use .035-.040" when BB turbo. shouldn't ever need less than .060" when Journal. something between .060-.125" will suffice.
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Old 09-24-2010, 11:59 AM   #15
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Quote:
Originally Posted by Braineack View Post
you should use .035-.040" when BB turbo. shouldn't ever need less than .060" when Journal. something between .060-.125" will suffice.
I was close.
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Old 09-24-2010, 04:21 PM   #16
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Interesting, I've got some 3/16 rivets so I'll give one of them a try when I button it back up.
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Old 09-24-2010, 06:43 PM   #17
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3/16>1/8
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Old 09-24-2010, 07:04 PM   #18
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Right you are........I double checked them and they are actually 3/32. I may look around for a 1/16 if I can find one.
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