pvc sucking oil

[390owner]

How can I make sure my pvc is not sucking oil into the carb base. I have chrome valve covers and the guy who build my engine said the aftermarket valve covers dont have a good baffle and he thinks the oil is going through the pvc valve. The 390 is using too much oil. I only have 2500 miles on a complete rebuild and at 700 miles I have went through 2 quarts.

[cattleFEeder]

If your using 3/8 hose to the carb base stick a 1/4 or 3/16 hose inside of the pcv hose to restrict it some. Its cheap, quick and easy.

[427LX]

Just get a clear plastic fuel filter and install in the PCV line. That will show if any oil is being sucked up and trap the oil for a while.
I built my own custom air/oil separator and also use a clear fuel filter after the separator to verify any oil getting past it.
It is also a good idea to fabricate a baffle in the valve cover underneath the PCV opening and best to have valve located at front of valve cover.

[390owner]

I have chrome valve covers and I worked on the baffle in it today. When I drove it smoke was rolling out both pipes so I done something wrong. I stuffed some material down in the hole that was suppose to slow the oil down. I also jb quicked the sides of it. That was the wrong thing to do. I am going to put the stock valve covers back on tommorow if the parts store has the gaskets and see what that does

[67428GT500]

Are you sure you're not pulling through the intake gaskets?
                                                                            -Keith

[390owner]

It got way worse when I worked on the baffle

[wayne]

I had the number for gm pcv with a very small hole like 1/8 gm did this to fix oil burning for ls i think but i lost it.May be some one here can help i got off a ford forum.

[wayne]

The part number for the pcv valve is ac delco 12567915 this may help you.

[machoneman]

A Boss 302 PCV valve is ideal for hot rod engines as it also has about the smallest opening around.

As for oil splash getting past un-shielded breathers...read my old post here to another's question:

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Even with baffles, I do wonder if oil splash is getting sucked into the intake. See, most often an intake leak will be on one side (pass or drivers) or only a few cylinders. Seems your oiling all eight, hence it could be the PCV is nonetheless sucking in oil.

I had the same issue, to a lesser degree, on my hot 351W in my '70 Mach 1. I added a "Chore Boy" stainless steel sink scrubbing pad to the area above the baffle to block oil mist. Cheap and it worked.     

http://choreboyscrubbers.com/chore-boy-products/stainless-steel-scrubbers
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[427LX]

My system as pictured above works great. Note no oil in that plastic filter and it's been there for a couple years!
I just drain the tank every couple months and get a small amount of oil out of it.

[390owner]

Thanks for all the replies. I now have the stock valve covers on the 390. I put a new pvc valve in it. I also checked my rocker arm shafts to make sure the oil hole was down, they where down. I am going to drive it some and see what happens. I have about 2700 miles on the rebuild and it uses a quart about 350 miles. The builder said drive it a little more and see what happens

[CaptCobrajet]

I suspect you may be pooling a lot of oil in the top up there.  When you sealed the baffle off some, it may have become a better straw.  Lots of times, a little wear in the rockers causes excess oil, which gets sucked into the pcv.  If the hose is full of oil, you might try restrictions or new rockers.

[390owner]

I replaced the pvc valve. I think that has fixed my sucking oil problem I had no idea a bad pvc could suck oil that wayn The new one is dry everytime I check it. The old one was dripping with oil everytime