Why the PCV valve soaks the intercooler
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From: Kihei, HI (most of the time)
I-menace: From looking at various seperating filters, there are subtle, but significant differences in water seperating and oil seperating filters. Both are coalescing filters, but the media is different. I would not expect the oil to vanish from the filter. I have recently installed one and will be watching it to see how much oil accumulates in it.
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From: Corpus Christi, TX
Originally posted by got hp
That is not true at all. Go to some of the forums for the 03/04 Cobras and you will see they have the same problems with oil in the throttle body, intercooler, etc.
You may get every other Lightning or Cobra guy to say they have no problems at all with oil, but most and even mine in stock trim does the same thing.
I tried to also be PC but there is no way unless you install a seperator (that actually works) or install a real baffle in the valve cover. I had thought about putting a baffle underneath the oil fill opening on the pass valve cover and running the pcv valve to the fill tube. That way the oil would have to make a hell of a journey past the baffle and up that tube before it got anywhere near the pcv valve. I would also like to install a one way pcv valve and remove the restriction on the lower intake galley line (at the fitting). This way under normal driving conditions and at idle, the pcv system would work just the way it is supposed to. At boost, the crankcase would not get fed pressure and no oil in the intake boot. You would also eliminate any oil in the intercooler and if any oil does get sucked up, however slight that might be, it would be after the intercooler.
So far the dual breathers idea has been working just fine and have noticed no ill effects as of yet.
That is not true at all. Go to some of the forums for the 03/04 Cobras and you will see they have the same problems with oil in the throttle body, intercooler, etc.
You may get every other Lightning or Cobra guy to say they have no problems at all with oil, but most and even mine in stock trim does the same thing.
I tried to also be PC but there is no way unless you install a seperator (that actually works) or install a real baffle in the valve cover. I had thought about putting a baffle underneath the oil fill opening on the pass valve cover and running the pcv valve to the fill tube. That way the oil would have to make a hell of a journey past the baffle and up that tube before it got anywhere near the pcv valve. I would also like to install a one way pcv valve and remove the restriction on the lower intake galley line (at the fitting). This way under normal driving conditions and at idle, the pcv system would work just the way it is supposed to. At boost, the crankcase would not get fed pressure and no oil in the intake boot. You would also eliminate any oil in the intercooler and if any oil does get sucked up, however slight that might be, it would be after the intercooler.
So far the dual breathers idea has been working just fine and have noticed no ill effects as of yet.
When I first saw it, it scared the he!! out of me. I was thinking "Here we go"! I followed the oil trail and it covers the underside of my truck all the way back to the pumpkin. It appears that it was all coming from the front breather on the passenger side. When I left San Angelo, it was right on the full mark. Checked the oil when I saw all of the oil on the motor and it was 1.5 qts low. I made the trip in 4 hours so I had the hammer down. Maybe that's part of the cause.
Looks like I'm gonna have to install an oil seperator or put it back to stock. Man I really hate the thought of that oil getting back into the I/C and galley. Especially after Clay and I worked so hard to clean that biatch.
Oh well it was worth a shot. 
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From: El Paso, Texas
well it seems that the method I had previously (although not endorsed by Red92) was to use a regualr one way pcv valve and run it to the lower galley line only. You can then block off the line that runs to the plenum (dime trick) and leave the drivers side line from the valve cover hooked up to the throttle body boot.
If you get any oil consumption, it will be AFTER the intercooler and there will be no oil in your throttle body. There is enough suction on the line to evacuate the crankcase at idle and on decel but not at zero vacuum or boost. Any pressure that builds up in the crankcase goes up through the drivers side line to the throttle body. Since the boost is no longer going into the crankcase and coming out the drivers side tube with oil, you won't get the oil in the TB.
I'd rather have a clean engine and some oil consumption (if any) after the intercooler.
If you get any oil consumption, it will be AFTER the intercooler and there will be no oil in your throttle body. There is enough suction on the line to evacuate the crankcase at idle and on decel but not at zero vacuum or boost. Any pressure that builds up in the crankcase goes up through the drivers side line to the throttle body. Since the boost is no longer going into the crankcase and coming out the drivers side tube with oil, you won't get the oil in the TB.
I'd rather have a clean engine and some oil consumption (if any) after the intercooler.
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From: Kihei, HI (most of the time)
I'm not sure about that, got hp, because I've seen some really slimy intake boots and throttle bodies and all of that oil has come from the left side valve cover. I like the idea of the dime trick and if you do a one way on the right side between the manifold bottom and the valve cover, if it is oriented so the flow goes from the manifold into the valve cover, the valve cover will see full boost and the left hand line will feed everything out of the crankcase into the intake boot. If the valve only allows flow from the cover to the bottom of the intake, the vacuum will carry oil vapor from the valve cover to the intake bottom. That should not be a big problem, because it will accumulate slowly and you could drain it, using a vacuum, every now and then. I still think you'll need a seperator on the driver's side to keep the oil out of the intake elbow, throttle body, blower and yes, the intercooler.
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From: El Paso, Texas
back when I had it like that, my intake boot was clean as a whistle. The oil in the throttle body boot comes from the drivers side valve cover but only under boost as the line from the lower galley is pressurized and feeding into the pass valve cover and upper plenum. If the line from the galley is only allowed to give vacuum on the pass side valve cover and the new pcv valve does not allow boost into the pass valve cover via that line, there is no way that oil can be forced up through the drivers side valve cover. It is forced up not sucked up. When I did my intercooler cleaning a couple of months back, there was no pooling of oil in the galley nor was there any oil in my boot to the tb.
I have had great success running it like this on my Mustang when it was supercharged. Never had any oil leaks and never had any oil in the fresh air line running to the inlet of the supercharger. Boost was never allowed to enter the crankcase because of the pcv valve. Granted not all of it was held back (18psi of boost) but I never had any problems.
I think it has been agreed upon that the reason Ford routed the pcv like this was to keep the lower intake galley free of oil. Had they just put a real baffle in the valve cover(s), a lot of our problems would be solved.
I have had great success running it like this on my Mustang when it was supercharged. Never had any oil leaks and never had any oil in the fresh air line running to the inlet of the supercharger. Boost was never allowed to enter the crankcase because of the pcv valve. Granted not all of it was held back (18psi of boost) but I never had any problems.
I think it has been agreed upon that the reason Ford routed the pcv like this was to keep the lower intake galley free of oil. Had they just put a real baffle in the valve cover(s), a lot of our problems would be solved.
