Engine Oil In The Intake Via Pcv Solved... Really

theYman

Active Member
Jun 5, 2013
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I have researched this topic extensively and have tried multiple fixes. I have used an oil separator, full length intake baffle, larger lines, etc. None of them were 100% successful until now.

I was reading another post from 2006 and the original poster claimed success with this same setup, so I tried it,and it flat out works. I would give him/her credit but I can not find the post now.
It involves using 2 pcv valves ( I used the Lightning pcv) elevated away from the intake. The pcv in the intake is replaced with a 3/4" male to male fitting, then a section of 3/4" heater hose mine is 3", into a 3/4" T, a hose on each side of the T joins 3/4" 90's, then another hose that house the pcv valves on each side. Then the pcv's 90 fitting are connected to each other via a 3/8 T fitting.
Finally, the other leg of the 3/8 T is connected to the line that goes into either your intake vacuum or your oil separator. I kept my separator to monitor if any oil makes it that far, so far none has.
After multiple full throttle blasts I have yet to see any oil in my separator or out the exhaust. Before this mod, my car would smoke after a long idle time and a WOT blast. I have included a diagram that I made to help explain it and picture of my setup .
I have also checked crankcase pressure/vacuum to be sure there are no difference between a single/dual pcv set up. In both situations with my vacuum/pressure gauge attached to my dipstick tube the reading were identical at 2"HG vacuum.
The theory of using 2 pcv's is to decrease the velocity while maintaining the volume of air. Less velocity will carry less oil.
With this mod my car seems to have a deeper exhaust tone, It also does not smoke at all , and the oil separator is bone dry.
pcv fix.jpg
!cid_20150908_1951551.jpg
 
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Nicely done. I can see by your diagram how far up that PCV hose, the oil will want to go. Once it gets to that slow portion, it won't go any higher and will eventually drain back into intake when the motor is shut down.

Not bad at all. :nice:

This is essentially what a catch can does except the can retains the oil when the music stops.
 
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I have researched this topic extensively and have tried multiple fixes. I have used an oil separator, full length intake baffle, larger lines, etc. None of them were 100% successful until now.

I was reading another post from 2006 and the original poster claimed success with this same setup, so I tried it,and it flat out works. I would give him/her credit but I can not find the post now.
It involves using 2 pcv valves ( I used the Lightning pcv) elevated away from the intake. The pcv in the intake is replaced with a 3/4" male to male fitting, then a section of 3/4" heater hose mine is 3", into a 3/4" T, a hose on each side of the T joins 3/4" 90's, then another hose that house the pcv valves on each side. Then the pcv's 90 fitting are connected to each other via a 3/8 T fitting.
Finally, the other leg of the 3/8 T is connected to the line that goes into either your intake vacuum or your oil separator. I kept my separator to monitor if any oil makes it that far, so far none has.
After multiple full throttle blasts I have yet to see any oil in my separator or out the exhaust. Before this mod, my car would smoke after a long idle time and a WOT blast. I have included a diagram that I made to help explain it and picture of my setup .
I have also checked crankcase pressure/vacuum to be sure there are no difference between a single/dual pcv set up. In both situations with my vacuum/pressure gauge attached to my dipstick tube the reading were identical at 2"HG vacuum.
The theory of using 2 pcv's is to decrease the velocity while maintaining the volume of air. Less velocity will carry less oil.
With this mod my car seems to have a deeper exhaust tone, It also does not smoke at all , and the oil separator is bone dry.
pcv fix.jpg
!cid_20150908_1951551.jpg
Well done! I'm going to give this a try on my new setup!
 
Nice application of some basic physics. This is something to remember when guys with pressurized induction show up with oil in the intake track.
 
One other thing I would like to add to this post. With the car idling and the dual PCV setup, I attempted to remove the oil fill cap and was surprised at how strong the vacuum is. Almost strong enough not to be able to remove the cap with one hand.
 
One other thing I would like to add to this post. With the car idling and the dual PCV setup, I attempted to remove the oil fill cap and was surprised at how strong the vacuum is. Almost strong enough not to be able to remove the cap with one hand.


In a closed system at idle, this is what you would expect. :nice: