pcv

[94snake]

so i was messing around under the hood yesterday chekin fluid levels n wut not and pulled the pcv piece out from the lower manifold and noticed a little bit of oil there !!.... very curious cuz have been noticing a lil oil cunsumption say half court every 2 weeks... aggrivates the hell outa me becuz motor is fresh 306 less then 12k on it... any ideas?

[vristang]

This CAN be a natural consequence of upgrading the intake system. h/c/i all create greater airflow and vac, which can pull more air from the crankcase than the pcv was intended to handle. Some people have had very good luck simply installing an oil separator in between the pcv and intake. Home Depot and Lowes both sell different variations. Look for them with Air Compressor Accessories.

This may not be needed though. Sometimes a restrictor can be placed on the TB/VC line.

If the rings are not properly seated (there can be several reasons), then the problem will likely just get worse.

A more extreme fix can be to use a vac pump (either e- or crank driven), to pull air from the crankcase. This will help seat rings better, and is almost required when using low tension piston rings. Just be sure to use an oil catch can (one of the real ones from Moroso or the like), because most of these air pumps do not live long when exposed to high levels of oil.
I am working on a similar system now, but have yet to work out all the bugs.

Hope this helps
jason

[94snake]

thanx for the info bro helps a little , so if i am noticing oil on the pcv i should try an oil seperator as you said?? preciate any help .... an will continue to chap ls1's asses

[vristang]

The separators may do the trick for you.

Also, I didn't mention the pcv screen that goes under the pcv. This is quite often left out when upgrading manifolds and engine rebuilds.

At about $20, the separators are worth trying.

To make sure that you don't have any major problems causing the higher crankcase pressure, it would be nice to do a compression check on all 8 cyl. I have been told that sometimes a ring or 2 just won't seat. I can't say how common this is though.

What do you know about the rings that were used in your engine? If they were low tension rings, that would def. cause this problem.

[mustangII460]

Make sure the screen under the PCV is clean, if it ain't, it will suck oil up the PCV.

Clean it, or buy a new. Use a wood screw or a pic of sorts to remove it. Pull the rubber groment out 1st.

[94snake]

thanx for the info ... yeh, recently cleaned the screen under pcv ...... the Rings r what Ross sent me with the 30 over forged pieces I told em i wanted power adder down road n thats what they sent me, ummm i wanna say they wer file to fit not positve... thought replacing the factory heads w\ EDEL RPMS would do it, helped alot but now it cunsumes oil Very slow ....Aggravating thanx

[vristang]

My experience with low tension rings...
The rings that came in my stroker kit were low tension. I did not consider that they could be any thing other than standard rings. When I did a leakdown test I found that it was at 20%. All of that blowby was pressurizing the crankcase and blowing oil all over.

I will give Ross the benefit of the doubt and assume they did not send you a low tension set, but a few minutes spent doing a leakdown test can eliminate this as a source of the problem. Also, you have not mentioned some of the other problems that are common with low tension rings such as; blowing out lower intake gaskets/seals, blowing the dipstick out of its tube, and oil loss through the front and rear crank seals.

Right now I would think that a small separator should work well for you.

jason