usc iroc

Hey guys...I have a question. I was wondering on my engine the pcv system is setup like factory. The driver side PCV has a good vacuum pulling vapors from the crankcase into the intake. On the passenger side valve cover the vapors are coming out (positive flow) of the valve cover instead of having a vacuum.
Question is I thought that there should be a vacuum at the passenger side valve cover drawing fresh air to the driver side valve cover which has a vacuum pulling out the vapors to the intake. "Cicle of Air" Driver side pulls air into the crankcase from the passenger side fresh air feed through the tube from the TB?

Apeiron

Clean air goes in one side to flush out the blowby gasses that are sucked up by vacuum on the PCV valve on the other side. The "flushing" is what makes it "positive" ventilation. If you put vacuum on both sides there's no flow.

OrangeBird

iTrader: (1)

If you've got a good suction at the PCV valve , and have pressure coming out of what is supposed to be the inlet side of the system (the valvecover opposite of the one with the PCV valve in it) there can really be only a couple or few ways for this to happen . Am I to guess that you see a bit of smoke coming out of the passenger side valvecover with the breather disconnected and the PCV valve installed and that's where you see the pressure ? As smoke where the air is supposed to be being sucked in ?

If the engine were blowing by so much as to overwhelm the PCV system , it should exhibit other symptoms of this severe blow by as well . If there were such a vacuum leak between one valvecover to the next (China wall RTV gasket , maybe ?) that could explain it but there is usually also quite a bad oil leak associated with this as well . If the engine was so full of sludge from neglected oil changes this could "clog up" the air path between the two valvecovers too . Knowing a bit about the "rest of the story" can sometimes help in diagnosing these kinds of things .

Good Luck ...

usc iroc

Yes...There is some smoke coming out. I disconnected the fresh air line at the throttle body and no air was coming out nor was there a vacuum at this port on the throttle body. The car didnt change idle or anything. The port for the vapor canistor below this port has a strong vacuum and a great affect on the engine if disconnected . Didnt know if the port was clogged or if it normally doesnt have a positive or negative flow, which didnt seem to make much sense to me.

Where would these ports be between the two valve covers

usc iroc

Should the air be "forced" in by the air coming out of the throttle body port? I can disconnect the fresh air line at the throttle body and nothing happens to idle quality nor is there and vacuum or air coming out of this port

Apeiron

Well first, what induction system is this? TPI?

usc iroc

Yes TPI with Accell 58mm and stealth ram

Apeiron

Yes, when you disconnect the fresh air line at the TB there's no noticeable vacuum or flow.

usc iroc

So then the process is actually a vacuumed system that pulls air from the passenger side to the drivers side through a passage in the intake valley. Where would these passages be located?

Apeiron

There's no passages in the intake. The air flows through the oil drainback holes in the heads and block.

usc iroc

ok thanks for the information. looks like I may need to do a compression/leakdown test. May have a bad ring since I am getting the blowby.

joshc

iTrader: (1)

Any oil consumption or running issues? (smoking or lack of power, low compression?)
If no issues, I don't know that I'd worry too much about it.

The fresh air line won't usually have a noticeable vacuum . as long as pressure isn't coming out it you're good to go.

usc iroc

No...I had recently rebuilt the motor and have only put about 50 miles on it because my tuner broke and it took 3 weeks to get it back. The original prom was WAY out of tune so I just let it sit. Anyway...When I started driving it I noticed it had more blow by than usual but I think it is just because the rings haven't seated etc.... I am just going to run it with no PCV for a few hundred miles and then see what happens.

vetteoz

iTrader: (13)

So Google how to run it in properly and go and do it.The rings need to be loaded up
If you are too soft on it it may take longer for the rings to seat.

What do you think that will do ?

usc iroc

Thats my plan Saturday....miles, miles, miles...
WHat I am being told is it will help with relieving any pressure till the rings have properly seated...who knows...I am learning that what didnt work for one worked for others and what sounded crazy to some was the saving grace of others. Just have to gather everyones opinions based on what worked for them and see what will work for mine. It would be to simple if it was all black and white but if that were so we wouldnt have so threads and post of people asking questions. They would just buy the book.
I think it is awesome to have a place like this to get help and options to choose from.

joshc

iTrader: (1)

Leave the PCV in,,, if any pressure builds up, it will just go out the vent side tube.
Pressure is less likely to build up with the PCV sucking it out.

usc iroc

Good point...I reconnected it