Makes sense now that I've heard the explanation. Thanks for the info!
*DIY* Oil Separator/Catch Can w/Pics & Write Up!!! :)
- Thread starter HandsomeRob
- Start date
Did you forget that a PCV valve is a one way valve? You cannot force air into it. And the other side of the PCV system should always be plumbed after the air filter and before a blower if done correct. It will pressurize the crankcase on a centrifugal blower if you dont move it.....
With the 96-98 blown cars, if you get some blowby around the rings you could blow oil vapors out of both valve covers.
The same is true with the 03/04 Cobras, plus they drain the lower intake unto the PCV circuit. Since the lower intake is pressurized under boost, the PCV circuit is also pressurized. Since PCV valves aren't the greatest valves in the world, they often let boost into the crankase which can dump a lot of oil vapor back into the TB. That is why a lot of Terminator owners add this valve to their PCV line after the PCVvalve:
ANDAIR CHECK VALVE from Aircraft Spruce
Probably wouldn't hurt to put one of those between the intake tube and the passenger side cover to prevent blowby from going back into the intake pipe. Tight fit though.
The same is true with the 03/04 Cobras, plus they drain the lower intake unto the PCV circuit. Since the lower intake is pressurized under boost, the PCV circuit is also pressurized. Since PCV valves aren't the greatest valves in the world, they often let boost into the crankase which can dump a lot of oil vapor back into the TB. That is why a lot of Terminator owners add this valve to their PCV line after the PCVvalve:
ANDAIR CHECK VALVE from Aircraft Spruce
Probably wouldn't hurt to put one of those between the intake tube and the passenger side cover to prevent blowby from going back into the intake pipe. Tight fit though.
If you have a blow-through setup try using a PCV valve meant for a turbo T-bird. It has a check valve in it to prevent you from pressurizing your crank case. :kaboom:
Back on topic.. I cheat.. I use a $7.00 NAPA fuel filter in line with the PCV on the wife's n/a 4V. Works great at catching oil, the only downside is I can't drain it. I have to change it about every other oil change but it is less stray line under the hood
Here is the catch can that I made. Only thing I did was change out the lines. I may move it somewhere else as I can smell the contents when not moving since I have it at the cowl. http://www.svtperformance.com/forums/engine-tuning-214/604615-how-make-catch-can.html
Here is the catch can that I made. Only thing I did was change out the lines. I may move it somewhere else as I can smell the contents when not moving since I have it at the cowl. http://www.svtperformance.com/forums/engine-tuning-214/604615-how-make-catch-can.html
Nice looking catch can setup:beer:
Only if there is an insane amount of restriction in the inlet pipe..
So how come when people upgrade to an Anderson Power Pipe they gain 1-2psi of boost? Would you consider the stock supercharger inlet pipe and a filter "a restriction"?
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The only way to know for sure is to put a vacuum gauge on your intake pipe to see if there is a vacuum there. Normally there isn't, but if there is, you need a better/cleaner air filter and/or a bigger pipe.
*Final Update*
4000 miles with the copper mesh!
Works great!! That's a lot of oil!!
4000 miles with the copper mesh!
Works great!! That's a lot of oil!!
Bump
I just emptied another full container of oil
I can't believe how good this separator works
I can't believe how good this separator works
i ran the return into the window fluid opening that goes to the fender well....the oil burns and causes problems down the road
This is one of the best threads I've seen regarding the different ways a PCV should be set up, specifically with regard to centri setups..
When I installed my procharger, I honestly can't remember how the drivers side PCV was routed, or whether I capped off the nipple on the intake and used a breather.. but I did have the passenger side routed to the intake tube of the blower.
When I installed my new engine, I just put breathers on both sides because I didn't want the smoke and oil going through the system, gunking up the blower, throttle body, and intake again, not to mention contaminating the MAF.
But just recently, I decided to experiment and ran both sides to a T fitting, and then a single line to the blower intake tube. Since its not metered air, and it's never pressurized, theres no possibility of a vacuum leak or boost leaking into the crankcase... And just to see how much smoke and oil was actually passing into the blower intake, I used clear tubing for the 1 foot long section that goes from the T fitting to the blower intake pipe.
While I couldn't really notice much smoke or oil condensation in the clear tube, apparently there is still oil condensing throughout the system, including on the MAF because a few days and a few hundred miles after driving it, I got a lean code in both banks. It's not a vacuum leak, I just checked all my vacuum hoses and it pulls 20 inches at idle. And I didn't have this code prior routing the pcv to the blower intake. Plus, the pcv system I routed is before the MAF and can't create a vacuum leak. Most importantly, I don't have an oil separator with this setup..
I haven't had the chance to pull it apart to see how much oil got into the system. I'm gonna look at a few areas such as the blower compressor wheel, the bottom most part of the system near the intercooler to check if any oil is pooling there, and the throttle body, which was always spotless of oil when I had my breathers.. Not to mention, I'll clean the maf with maf cleaning spray..
I'll probably just go back to my breathers... But I was thinking of instead connecting the single T'd line from both sides to the nipple on the upper intake on the passenger side (making sure to also use a check valve in the line) because I'm well aware the the pcv valves don't make a very good seal. I guess I could also use an oil separator if I were to do this.
My question is, why did ford connect one side of the pcv before the throttle body, and the other side after the throttle body from the factory? Even though both were after the MAF, you'd think that air would leak from one side to the other, basically like opening the throttle body... Right?
But if I T'd both sides to the port after the throttle body, and used a check valve so no boost leaked past it, I should be fine, right? Now that I think of it, probably not, because the PCV valves themselves dont have a very good seal into the cam covers when you press them in, there could be a vacuum leak around the pcv.
Aaah screw it, I'm just gonna clean my maf, see how much oil got into the system, and put my breathers back on. That's the simplest thing to do with the least possibility of any boost / vacuum / metered air leaks.
Just out of curiosity, what is the default pcv routing mentioned in the installation manual for a procharger setup? What the hell do they tell you to do with the drivers side hose that connects to the manifold? Leave it stock? That can't be, because one side would be metered and the other side wouldn't..
When I installed my procharger, I honestly can't remember how the drivers side PCV was routed, or whether I capped off the nipple on the intake and used a breather.. but I did have the passenger side routed to the intake tube of the blower.
When I installed my new engine, I just put breathers on both sides because I didn't want the smoke and oil going through the system, gunking up the blower, throttle body, and intake again, not to mention contaminating the MAF.
But just recently, I decided to experiment and ran both sides to a T fitting, and then a single line to the blower intake tube. Since its not metered air, and it's never pressurized, theres no possibility of a vacuum leak or boost leaking into the crankcase... And just to see how much smoke and oil was actually passing into the blower intake, I used clear tubing for the 1 foot long section that goes from the T fitting to the blower intake pipe.
While I couldn't really notice much smoke or oil condensation in the clear tube, apparently there is still oil condensing throughout the system, including on the MAF because a few days and a few hundred miles after driving it, I got a lean code in both banks. It's not a vacuum leak, I just checked all my vacuum hoses and it pulls 20 inches at idle. And I didn't have this code prior routing the pcv to the blower intake. Plus, the pcv system I routed is before the MAF and can't create a vacuum leak. Most importantly, I don't have an oil separator with this setup..
I haven't had the chance to pull it apart to see how much oil got into the system. I'm gonna look at a few areas such as the blower compressor wheel, the bottom most part of the system near the intercooler to check if any oil is pooling there, and the throttle body, which was always spotless of oil when I had my breathers.. Not to mention, I'll clean the maf with maf cleaning spray..
I'll probably just go back to my breathers... But I was thinking of instead connecting the single T'd line from both sides to the nipple on the upper intake on the passenger side (making sure to also use a check valve in the line) because I'm well aware the the pcv valves don't make a very good seal. I guess I could also use an oil separator if I were to do this.
My question is, why did ford connect one side of the pcv before the throttle body, and the other side after the throttle body from the factory? Even though both were after the MAF, you'd think that air would leak from one side to the other, basically like opening the throttle body... Right?
But if I T'd both sides to the port after the throttle body, and used a check valve so no boost leaked past it, I should be fine, right? Now that I think of it, probably not, because the PCV valves themselves dont have a very good seal into the cam covers when you press them in, there could be a vacuum leak around the pcv.
Aaah screw it, I'm just gonna clean my maf, see how much oil got into the system, and put my breathers back on. That's the simplest thing to do with the least possibility of any boost / vacuum / metered air leaks.
Just out of curiosity, what is the default pcv routing mentioned in the installation manual for a procharger setup? What the hell do they tell you to do with the drivers side hose that connects to the manifold? Leave it stock? That can't be, because one side would be metered and the other side wouldn't..
Because the PCV valve is a check valve, (ignoring blowby) air can only flow from the intake air pipe through the passenger side valve cover, down through the crankcase, up through the driver's side valve cover, through the PCV valve and into the intake manifold after the TB.
At idle and part throttle, it flows that way because the air in the intake air pipe is at ambient pressure and the air in the intake manifold is at about 22" Hg of vacuum. At WOT in an NA motor, the air in the intake pipe and intake manifold are at the same pressure so not much air will flow through the PCV system. Any pressure caused by blowby will be free to go through either side into the intake manifold.
Under boost, the PCV valve is supposed to keep the crankcase from being pressurized. But it doesn't always seem to work so a lot of high boost guys add an aircraft rated check valve such as the Andair unit:
ANDAIR CHECK VALVE from Aircraft Spruce
Part # 05-00719 with no bleed.
I am sure when you are in boost, any blowby will go through the passenger side into the intake through the TB, since it would have to be higher pressure than the boost to go the other way.
If I could get away with it on the street here in CA, I'd run a crankcase vacuum pump, or a Moroso PCV scavenging kit in order to get a bit of a vacuum in the crancase at WOT. Should be good for one or two HP and a clean engine and engine compartment. Doesn't do much for the environment, though, but no worse than venting.
Here is the Moroso Crankcase evacuation system: Moroso 25900 - Moroso Crankcase Evacuation Systems - Overview - SummitRacing.com
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This custom oil separator I made is now for sale. Anybody interested?
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