DIY Oil Separator or Catch Can, or let it burn?

[Desert Patina]

I wanted to know y'alls thoughts on Oil Separation in the PCV system. (Also posted at FourEyes)

The 2.3L turbo motor has two oil separators, basically cans that slow the air down enough to help drop the oil out of it, which then drains down back through the same hole it came in.

Not only am I missing the one on the car I recently purchased but it seems these have a tendency to fall out from a few of the complaints I've read on a number of forums.

This has lead me to a dillema...

The person before me simply glued in a PCV valve in the hole with some orange make-a-gasket.

If I were to really separate out the oil I would use a catch can. From what I've seen this can be accomplished with no less than (don't quote me I've never tried this and I'm not experienced enough to really tease out the details either)

* 1/2" NPT to be screwed in where the hole in the block that loosely holds the regular oil separator has been tapped for threads.

* A gutted water separator from any local store which sells Pneumatic parts

* add some adapters and lines to fit.

* A clamp to secure the catch can to something in the engine bay

* Maybe some steel wool or pan scrubber made of metal

The real dilemma, however, is what do I do with the oil? Some ideas I've seen are let it drain back to the oil pan (which would require a feat of engineering as I see it). But others say don't let that junky oil back in, just let it drain onto the road (which seems to defeat the purpose to me). Others throw it out, which is as annoying as having to take out the trash but from your engine compartment.

Perhaps the best thing to do is to just burn the oil then?

[MikeFleming]

The PCV system isn't intended to specifically handle the oil, but rather to handle the airflow requirements to keep the crankcase purged of combustion byproducts. Managing the oil is an additional benefit - as proper running engines won't have much oil in the vapors to handle.

Read up on "Type 4 PCV" systems to understand how the system is intended to work.

Yes, you will need to provide a way for catch-can collected oil to be managed. Manual drain and return, or more plumbing.

BTW - I have never seen - or heard of - the block-mounted one having a tendency to fall out. The installed intake manifold would prevent that all by itself. The cam cover mounted ones may have a tendency to do that though.

[Desert Patina]

Hello again Mike, thank again for your diligent vigil over those with questions. It means a lot that I know that no question will fall through the cracks here.

No worries, though I'm a computer scientist I'm trained in Mechanical Engineering and have done a few projects over the years. The problem is that was 20-10 years ago on the Ford/Mazda 1.3l that comes in the Festiva (and the 1.6l B6T variant of it), and while its the same era I have been more than surprised on the unique peculiarities of this engine. Its been along break from the action where I concentrate on raising three small children, who are now entering pre-teen life.

On that engine I never had to worry about an oil cooler, or oil separation in the PCV system. I can't remember if it had that or not, even. I think the most it had was a filter pad in the PCV intake that supposedly caught the oil and required changing regularly, but again my memory of it is very rusty. Then again, I've never heard of different types of PCV, but I think what you mean by type 4 is what California Emissions considers a closed system (vents to the intake), and the other types involve a breather either to the exhaust or atmosphere?

For this thread I really am only interested in the oil separation, and I apologize for not giving a more broad treatment of the system. I'm considering strongly to do without the oil separator can on the crankcase, and want to make sure I have my bases covered or maybe even improved on.

Right now all I have is a review of what is likely reliable information I've found (which I admit I'm not entirely qualified to judge) ...

Here's the thread on the breather's falling out. Looking at it closer, these engines could easily be carbed...

http://www.4m.net/showthread.php?172...)-on-2-3L-ford

While I'm listing what I have interest in resolving, I should add the concern I've seen on various forums that the PCV valve is useless in the turbo. At TurboFord they suggest a checkvalve, here's an example of a home made check valve ...

http://forum.turboford.org/cgi-bin/u...c;f=4;t=000338

At the same time, Stinger (the same Stinger?) suggests that for a Turbo application any kind of PCV valve is useless since the system is often pressurized rather than in vacuum (which we know means the system is not circulating and doing its job then). Others say even on N/A engines at WOT there the PCV is not working very much. But whether Stinger is only concerned about the 1/4 mile or the freeway also, I have to admit I'm not sure.

http://stinger-performance.proboards...ead=732&page=1

I've seen these same issues presented many times, and this selection is just the most typical of them.

For me I want something that maintains its reliability on the race track as well as the freeway. Which means I'm looking to maximize the ventilation, and perhaps minimize the oil consumption in a car that radically changes from vacuum to boost, and might stay at boost for elevated periods.

But then again, I realize I'm a computer scientist who is more accustomed to making HPC systems work reliably and efficiently and that the same principles I've developed there might translate to worrying about nothing major on the engine. But it is my inclination to find the answer to that by knowing more about the system.

So again, thanks for your input. I appreciate your opinion.

[Bob Holmes]

Even on the racecar I have the block oil separator installed. The EFI manifold will hold it in, try taking one out when the mani is installed.

I don't see an advantage to removing that part and then installing the commonly used "pressurized air" filter that comes in so many of the kits. The stock one drains back into the block, the aftermarket product requires you to plumb back into the engine, or you have to perodically drain the filter.

But different strokes for different folks.

[Desert Patina]

If it means anything, Bob, if I had one I'd run it and my worries would be over

I'm giving the local pick-a-part another try this weekend. There is some fresh meat there, a few recent late 80's mustangs and early 90's Rangers. Hopefully I'll get what I'm looking for.

All this hand wringing comes because I have to find options.

[Stinger]

I've actually used my method outlined above on both an SVO and my turbocharged 06 GT (in a slightly modified form). I find the SVO will accumulate some oil over time (presumably from the greater boost pressure and higher mileage engine) while the 06 GT only accumulates a "dirty water" substance. The "oil" that's in the SVO's catch can isn't something I'd want to put back into the system though as it's milky after it mixes with the condensation. The only differences between the catch can setup in the SVO and the GT is that the SVO has a filter on top of the can that releases fumes to atmosphere while the GT has a sealed can that has a hose that connects back into the turbo inlet (like the stock SVO PCV system) to draw vacuum on the catch can and also prevent fumes from escaping, and that the GT pulls from both valve covers rather than the single valve cover and the crank breather on the SVO.

With that said, both of my cars no longer have any issues with pushing out the dipstick, blowing oil out of any gaskets/seals, etc. I can provide pics of the "closed" catch can system referenced above if you want.

[Desert Patina]

Yeah, I would. Many thanks.

[Stinger]

You've seen the SVO setup in the link above to my write-up but here it is again for reference. Note it simply vents from the stock crankcase breather/separator, the valve cover breather/separator T's into it, then it enters the catch can. Excess air/blowby/fumes vents out the filter on the catch can.


As for the 06 GT, here you can see the 5/8" hoses running from the driver's side valve cover, around the back of the engine to the passenger side strut tower area. There is also a hose from the passenger side valve cover with a "T" into the driver's side hose before it goes into the catch can mounted to the passenger strut tower.
The catch van vent hose then exits the can, routes behind the engine and goes to the turbo inlet between the filter and the turbo. The turbo inlet draws vacuum on the catch can, helping it pull crankcase pressure from the engine and keeps the system closed to keep the fumes at bay.
P1215203.jpg

Here is a better view of the driver's side:
P1215201.jpg

And a better view of the passenger side/catch can:
P1215199.jpg

[Desert Patina]

Thanks, I think I know exactly what I'm going to do now!

[Larry_S]

You've seen the SVO setup in the link above to my write-up but here it is again for reference. Note it simply vents from the stock crankcase breather/separator, the valve cover breather/separator T's into it, then it enters the catch can. Excess air/blowby/fumes vents out the filter on the catch can.

I know you do not have the PCV valve installed but do you have a check valve installed? Anyone have thoughts on Stinger's setup but instead of using stock valve cover breather/separator having an AN fitting welded to the cam cover and two hoses going to catch can? One hose from -12 fitting on valve cover and one from crankcase separator? Or is there some benefit using the stock breather element in Stinger's?

[Stinger]

I know you do not have the PCV valve installed but do you have a check valve installed? Anyone have thoughts on Stinger's setup but instead of using stock valve cover breather/separator having an AN fitting welded to the cam cover and two hoses going to catch can? One hose from -12 fitting on valve cover and one from crankcase separator? Or is there some benefit using the stock breather element in Stinger's?

No pcv, no check valve, just free flowing air. What are you hoping to gain with a check valve?

The stock breather in the valve cover doesn't have to be used, it was just the easiest way to do it with the type of hose I was using. Just make sure you have the internal baffle in the valve cover.

[Larry_S]

No pcv, no check valve, just free flowing air. What are you hoping to gain with a check valve?

I am hoping to gain not having oil exit exhaust under decel. As for the check valve I was just clarifying if you had one installed or not. I really do not want to put a great deal of thought into how system is supposed to work and re-engineer so if what you have come up with works I think I'll try the same approach. I have seen others mention similar solutions to your website post.

[blueboss]

Lemme preface this by saying, no offense. Just offering my opinion and perhaps another point of view. In the SVO example, you've created a glorified road draft tube type crankcase evac system. They used this from the 19th century until the mid 20th (around 1955 I think) until a scientist postulated this was a significant contributor to a growing smog problem. Major difference is, your design doesn't leave oil stains in the driveway and is even less effective as it's not even in the airstream when the vehicle is moving. I can tell you from personal experience that your design won't work for everyone.

I removed my stock block oil separator, tapped the the hole for a 1/2"npt -10 adapter and ran the line up to a Jaz vented catch can, no pcv valve. The valve cover was vented to atmosphere. Cold starts resulted in the engine smoking profusely until warm and oil pushing past the dipstick upon boost (10psi). And before you go there, brand new valve stem seals, good valve guides, head gasket, hot compression was within 5% @ 150, a leakdown netted less than 7% max and no, the turbo seal or anything related to the turbo was bad or kinked. The engine was/is in a perfect state of tune and it didn't smoke at any time before performing this mod.

The BIGGEST problem with the 2.3 turbo pcv system, is the size of the port/tube between the cam cover and the turbo inlet. This tube is not only an inlet but an outlet as well. When your vacuum is high (idle or cruise), the PCV valve is open and air is drawn from the turbo inlet, through this tube, down through the cam cover into the engine and into the crankcase pulling the blowby gasses through the pcv valve and into the intake to be reburned. Incidentally, this is where your engine will spend about 95% of it time when you're street driving. When vacuum is low/nil the pcv valve closes and the crankcase gasses now escape through the cam cover and into the turbo inlet to be reburned. When boosted, *WITH A GOOD PCV VALVE*, vacuum is low and boost pressure is pushing against a sealed closed pcv valve. Air *shouldn't be* moving past the valve into the crankcase and blowby gasses escape through the cam cover and into the intake tract to be reburned. The reason that some people occasionally push the dipstick tube out with a factory type pcv in place comes down to simple volume. The factory tube connecting the cam cover to the turbo inlet is simply too small. Pressurized air, just like electrons, will ALWAYS follow the path of least resistance. In this case, the combined volume of the dipstick tube and the cam cover vent offer lower resistance to flow than the cam cover vent alone and pushed out the dipstick. Many people, including myself at one time, mistake this as the turbo pressurizing the intake tract THROUGH the pcv valve and install the Mercury Villager brake check valve. Increase the diameter of the cam cover intake/vent tube, install the correct pcv valve and pushing the dipstick WILL go away.

In my case, there was no crankcase vacuum being pulled when cold which was causing the cold smoking. Apparently, cold ring sealing is a problem in my bottom end. Most likely needs rebuilt, but I digress: I already tapped my block for 1/2"npt and installed a -10 an adapter. I installed a pcv valve in the -10 hose and connected the other end of the pcv to the factory location on the lower side of the intake. I tapped my cam cover AND turbo inlet for the same 1/2"npt and installed -10 adpaters at both locations. I installed a Moroso 85471 air/oil separator (which is sealed and drainable) inline between the cam cover and the turbo inlet. This configuration stopped the cold smoking and stopped the dipstick pushing. My intake is dry and I retained the factory designed pcv system albeit significantly improved.

Why did I mention all this: The as delivered pcv system from Ford leaves a lot to be desired. But is has it's benefits as well. I see no logic in removing the pcv system altogether or installing one from the 19th century on a street driven vehicle. Makes no sense and it might not work well for everyone. To bring this back to the op's question(s), IMHO, you have two options. Stinger's method is simple, effective and gives you the opportunity to reuse the oil. It does not utilize the factory pcv system and there may be other issues that arise by eliminating the pcv system as well as benefits. My method is slightly more complicated, equally as effective and also gives the opportunity to reuse the captured oil. My method retains the factory designed pcv system and you get the cool Moroso contingency sticker for your tool box. Sorry for the longwindedness gents, I'm going back to my hole now.....

[blueboss]

As a matter of fact, it's similar the the system that Stinger has in the 06.

[Larry_S]

In my case, there was no crankcase vacuum being pulled when cold which was causing the cold smoking. Apparently, cold ring sealing is a problem in my bottom end. Most likely needs rebuilt, but I digress: I already tapped my block for 1/2"npt and installed a -10 an adapter. I installed a pcv valve in the -10 hose and connected the other end of the pcv to the factory location on the lower side of the intake. I tapped my cam cover AND turbo inlet for the same 1/2"npt and installed -10 adpaters at both locations. I installed a Moroso 85471 air/oil separator (which is sealed and drainable) inline between the cam cover and the turbo inlet. This configuration stopped the cold smoking and stopped the dipstick pushing. My intake is dry and I retained the factory designed pcv system albeit significantly improved.

I think I like your method and will try. The thing with my car is it is not a daily driver but rather a couple thousand miles a year. It was built for road racing although I have removed all the aftermarket suspension currently. I plan to try to sell if it does not sell in market I will probably reinstall road racing suspension and it will just be a toy to drive once in a while. Having said that can you post pictures of your install. Were you able to drill and tap the factory turbo inlet housing where the line was when stock? Thanks for long explanation.