Questions on oil catch can install after research

AaronB

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Engine is 89 7mgte.

I spent a good hour reading up on PCV systems and *proper* catch can setups and it creates more questions then answers.

First just want to confirm I have the flow right for a 2 port catch can. The line off of the throttle body, and the two valve cover vents all tee together and go into the inlet of the can. Outlet gets plumbed back into the accordian pipe.

Now I was reading some A80 threads and saw conversations about running dual catch cans, one on the Pcv side (for idle) and one on the intake side for when under boost. Is this something to consider? Or is the 2jz PCV system different?
I know running two is most likely Overkill even as an idea, I really am trying to have a proper setup, and also a proper understanding of this system.

My other question is involving a check valve. Seems to be mandatory on a turbo application, am I correct that it's just installed in the line that goes from the catch can outlet to the inlet on the accordian pipe?

I appreciate all your help, like I said this is equal parts wanted a safe setup, but also just understanding these systems.
 

JustAnotherVictim

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I only ran one from the ports off the top of the valve covers into the accordion hose. Always wondered how much moisture the baffling under the top of the valve covers actually caught myself. That would be the only reason to run it off the PCV side is if you think you're getting too much water back into your oil tank imo.

Never looked into the check valve part personally.
 

AaronB

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That's interesting running it only off of one valve cover, but makes sense. I'm just trying to keep oil out of the intake and IC piping.
 

3p141592654

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15 or so years ago this was a common site in Toyota dealerships, and a couple of the old timers here who worked for dealerships used to deal with this on a daily basis for a while. The 1MZ V6 sludge was the result of a sub par PCV design and short trips and poor maintenance. The factory design for the 7MGTE is pretty good. I wouldn't mess with it. If you really hate black intake manifold walls, then put a catch can in-line with it.

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AaronB

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Wow that's pretty wild looking. I'm glad to hear the stock PCV is quite good, and also I'm not looking to eliminate it, just add a catch can in-line to be an additional help. I probably am overthinking it, although it's a high mileage (243k) 7mgte that has some sentimental value, so I'm definitely doing whatever I can to ensure good health.

I guess to sum this up, I'll put a catch can in-line from the Pcv to accordian inlet (on the cold side) So the stock PCV is still active, and the catch can will remove vapors on the way back to the intake. Not too intrusive and stays close to OE.