PCV Delete - Using AIR Pump for Crankcase Vacuum?
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From: Winston-Salem, NC
PCV Delete - Using AIR Pump for Crankcase Vacuum? When I install my FAST 90/NW 90 setup in the next few weeks, I want to ditch the PCV system so that I don't have to worry about oil getting into the intake at all.
At the same time, I don't want to worry about a lack of crankcase vacuum causing ring seal and oil consumption issues.
A local performance shop suggested using the AIR pump that I've removed as a source for crankcase vacuum. Has anyone heard of this? If so - how does it work?
I'm assuming I'll need to run a breather off the passenger valve cover, and a line from both valve covers into a catch can, and from there, into the air pump. Is this correct?
Any help is MUCH appreciated!
At the same time, I don't want to worry about a lack of crankcase vacuum causing ring seal and oil consumption issues.
A local performance shop suggested using the AIR pump that I've removed as a source for crankcase vacuum. Has anyone heard of this? If so - how does it work?
I'm assuming I'll need to run a breather off the passenger valve cover, and a line from both valve covers into a catch can, and from there, into the air pump. Is this correct?
Any help is MUCH appreciated!
I havent heard of this "air pump" method first hand, but it makes sense on how it might work. I bet you can just get a breather for both valve covers and !PCV all together. I don't really see where the air pump fits into that equation with the catch can method though. 
Originally Posted by FstBlkz28
y not just throw a breather on it and call it a day ... thats what i'm doing after trying every combination of PCV valves and catchcan setups and still getting oil in the intake.
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Yes, I can get a breather for both valve covers and ditch the PCV, but that would leave me with no crankcase vacuum, which I don't like.
Good point oange ss, hopefully some other users can weigh in with more information. That would leave me with no crankcase vacuum, which I don't like. If you don't have any information that pertains to my specific question, please don't ***** my thread.
Good point oange ss, hopefully some other users can weigh in with more information.
Originally Posted by FstBlkz28
y not just throw a breather on it and call it a day ... thats what i'm doing after trying every combination of PCV valves and catchcan setups and still getting oil in the intake.
Originally Posted by FstBlkz28
y not just throw a breather on it and call it a day ... thats what i'm doing after trying every combination of PCV valves and catchcan setups and still getting oil in the intake.
I believe that he might have something to say, for your best interest, about this thread if one of your concerns is not allowing oil into your intake, which i am also looking for a fix.
Dont sound like a fool on your own thread...
Now, if we remove all of the pcv lines an run two breathers, i can understand since th4 vacuum will be lower due to the free flowing air. What if you ran only one breather? Will that help enough?
I can understand how this, low vaccum, might hinder some of the accesories that run of that vacuum but how will it hurt your seals? I have seen this posted before but unsure how.... I understand how alot of blow-by can cause to much crank pressure and balmo, seals go but not vacuum...
Last edited by obZidian; Feb 22, 2006 at 10:01 AM.
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i tried it and it wasnt strong enough to pull a good vacuum, so i just got rid of it and ahve been using breathers since.
if your serious about doing it your only real option is to get a real crankcase vacuum pump, one of those mechanical like morso sells.
if your serious about doing it your only real option is to get a real crankcase vacuum pump, one of those mechanical like morso sells.
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From: Winston-Salem, NC
Originally Posted by smokinHawk
i tried it and it wasnt strong enough to pull a good vacuum, so i just got rid of it and ahve been using breathers since.
if your serious about doing it your only real option is to get a real crankcase vacuum pump, one of those mechanical like morso sells.
if your serious about doing it your only real option is to get a real crankcase vacuum pump, one of those mechanical like morso sells.
I checked out the Moroso units at Summit Racing... pricey!
Are you having any negative issues using just the breathers? If you're happy with the PCV delete with breathers on a turbo car, I'm sure my N2O car will be fine with that setup...
Originally Posted by JoeyAnderson
Yes, I can get a breather for both valve covers and ditch the PCV, but that would leave me with no crankcase vacuum, which I don't like.
Good point oange ss, hopefully some other users can weigh in with more information.That would leave me with no crankcase vacuum, which I don't like. If you don't have any information that pertains to my specific question, please don't ***** my thread.
Good point oange ss, hopefully some other users can weigh in with more information.That would leave me with no crankcase vacuum, which I don't like. If you don't have any information that pertains to my specific question, please don't ***** my thread.
Originally Posted by obZidian
Not even a greddy catch can?
Last edited by FstBlkz28; Feb 22, 2006 at 10:25 AM.
ive only used a sears air\water seperator and ive had no issues with oil in the tb...its been done a few times before on this site, its cheep and it works great... id say just do that instead of overcomplicating a simple problem...jmo
Sorry to bring this back up from its 6 day death, but ive got some ideas for this. I have 2 AIR pumps laying around, and im going to tinker with them. Hooking them up they move a decent volume of air. Ill hook up a hose, with a vacuum gauge and get a reading this week some time. You could always run the pump to evac the crank case, and a breather with a restriciton to allow fresh air in. You need the restriction to create a vacuum, as theres too much volume in there to leave it unrestricted. So possibly a metal insert with epoxy and a drilled hole to get the vacuum that you want. Ive read that anywhere from 6-14" is good and wont mess with the seals. Now wether or not the AIR pump can even come close to that, ill know this week.
So my system will go like this. Restricted breather on one valve cover. Line for AIR pump somewhere on the motor, probly other valve cover. Water/Air seperator, to keep the oil out of the pump. AIR pump for vacuum. Line to the intake, or a welded pipe in the exhaust like the SBC EVAC kits that summit/jegs sell.
Only problem is that im going to be testing this on a little 1.5l honda motor, then possibly a 350sbc, or a buddies LS1, as mine is down for some work.
So my system will go like this. Restricted breather on one valve cover. Line for AIR pump somewhere on the motor, probly other valve cover. Water/Air seperator, to keep the oil out of the pump. AIR pump for vacuum. Line to the intake, or a welded pipe in the exhaust like the SBC EVAC kits that summit/jegs sell.
Only problem is that im going to be testing this on a little 1.5l honda motor, then possibly a 350sbc, or a buddies LS1, as mine is down for some work.
I want to run a breather setup on my motor. Is one working ok for some of you people? Or should there be one on both sides? It sounds like the amw catch cans still leave a little bit of oil vapors getting into the intake.
Originally Posted by JRracing
I want to run a breather setup on my motor. Is one working ok for some of you people? Or should there be one on both sides? It sounds like the amw catch cans still leave a little bit of oil vapors getting into the intake.
Last edited by FstBlkz28; Mar 1, 2006 at 06:22 PM.
I just put a breather on pass side and deleted pcv today. Having just installed PRC LS6 heads and seeing how nasty my intake manifold,runners on the old heads, and pistons were-forget it. I'm not having that happen again. I'll let everyone know how it works.
Here's a question thats semi related to the PCV delete about the TB.
I've got an S2 ported TB, once I delete the PCV system. I could fill in the hole that fed the valve cover w/ fresh air couldn't I (not the hole going to the IAC motor)?
I've got an S2 ported TB, once I delete the PCV system. I could fill in the hole that fed the valve cover w/ fresh air couldn't I (not the hole going to the IAC motor)?
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From: Anheuser Busch, Houston Texas
My understanding is that vacuum on the crankcase reduces pumping losses, slows contamination of oil from blowby, increases engine life/decreases wear, and is generally a good thing, up till you put so much on it that you start sucking oil off things that need oil on them...my reasearch indicates somewhere around 14" hg -ish. It also should relieve pressure from FI, if you give the extra pressure somewhere else to go in a closed system.
Just putting a breather on, if I understand correctly, will not allow enough scavenge of blowby, but does allow for some pressure relief (particularly in FI situations, eg. no more dipstick blowing and seals leaking). Breathers also do not catch any of the oily blowback fumes which would have been sent to the TB and burned again (or at least attempted to be burned) so instead it just gets all over everything in your engine bay.
For a really in depth discussion on this check out these guys:
http://www.3si.org/forum/showthread....electronic+pcv
They tried a lot of things, and at least did a lot of research on this pumping idea for vacuum.
Just putting a breather on, if I understand correctly, will not allow enough scavenge of blowby, but does allow for some pressure relief (particularly in FI situations, eg. no more dipstick blowing and seals leaking). Breathers also do not catch any of the oily blowback fumes which would have been sent to the TB and burned again (or at least attempted to be burned) so instead it just gets all over everything in your engine bay.
For a really in depth discussion on this check out these guys:
http://www.3si.org/forum/showthread....electronic+pcv
They tried a lot of things, and at least did a lot of research on this pumping idea for vacuum.
