Imo000

Very nice. For CS SC setups, this seperator could be sandwiched between the block and the existing oil filler neck, right? Or is it necesarry to have the top "cap" with the two breather lines? Instead I could modify the very top of the exisitng filler neck to accept two large vent tubes.

Louie928

I think it would be a good thing to sandwich the bottom part of this separator below the oil filler housing. That should trap some oil before it gets to the housing. The oil filler does have louvered opening at the bottom, but nothing special to trap oil in the big void before it gets that far. The (late S4) oil filler is plastic and prone to leak. If you can locate a '85/'86 filler housing, those are metal and hold the seal better.

Louie928

Bill,
You might be right about the pot scrubbers getting saturated with oil and some blowing out anyway. I should have blown air through while pouring hot oil into the air stream, but I always get in too much of a hurry to do real testing like that. I was hoping that the scrubbers would make the air/oil go in many different directions and eventually cause oil mist to coalesce into larger droplets that may drop out of suspension. But, I don't really know.

Louie928

Tony,
Does yours really work? You have a lot more running time under adverse conditions than my engine which is only dyno time.

Tony

I honestly dont have oil coming out anywhere(except my damn oil pan gasket) or the problems others seem to have. I havent opened up or taken out my seperator since i installed it originally. Its a sealed unit with a 1/4 drain tube that leads down by my drivers door. It also has a 1" dia hose that leads under the car where the vapors are "dumped". I have yet to see a drop under there either. The only thing i see near the tube is a feathered discoloration from the airflow probably coming out of it and any vapor. No oil streaks.


Below is the last seperator in my system. My home made on one the left(prior to celan up and powder coating) and the cutaway of the $300 FAA/PMA approved one on the right

Bill Ball

Obviously I really don't know either. I'm building mine with just casual notions and stuff from Home Depot.

It may depend on what's the more prominent problem. Is it oil slung up by the crack or is the misty cloud getting carried into the breather hoses and out to wherever. If it is the latter then the pot scrubber is a good idea. Considering the huge quantity of oil I lost at high speed, I thought there must be occlusion by liquid rather than vapor, but that cloud could be quite heavy. A view window in the breather hose would help answer that, like you did with the cam covers.

Tony

I think the real key is the size of the openings and the amount of inertial seperation you present to the mist of oil.
The flow velocity is WAY slower through the larger opening in my oil filler area than on the small 1/2 hole/tube Andy had on his kits. Mine also has many seperation "chambers".
As the airflow works its way up my seperator at the filler, it has to make many 90' turns. During each of these turns the heavier oil in the "mist" cant make the turn to the next level up so it drops out of suspension and hits the wall.....draining back down eventually. If it does make it up, it then has to make more turns as it exits through the pot scrubbers at the top. Since this seperator really doesnt offer much resistance to airflow, it allows the crank case to breathe easier. With that said i think the oil whipped around in the heads by the cams isnt being forced out the cam cover vents by excess pressure.....it drains down to the pan easier. (i think thats the idea)

Louie928

Tony,
Thanks for some confidence that the oil filler separator may help. Is your cylindrical aluminum separator similar inside to the PMA one?

Tony

I dentical..and id like to think better. I know its cheaper!

AO

Wow! There's a ton of info here... thanks to all who have contributed so far.

I got my replacemetn crank sensor yesterday, and was thinking about getting back to work on this thing before I head to Germany next week for business, but then I started thinking about this a bit more.

Below you can see a picture of DR's replacement filler plate. Looking at the first picture, he's got 2 pipes. The one on the right is a the breather pipe and it sounds like this will be too small to accomodate the CC pressure. The tube on the left (the thcker one) is the oil filler tube. That's it's only function.

So, what to do? Do I proceed with DR's replacement as is? Or do I take it somewhere to get it modified ala Tony/Louie?

I'm pretty sure DR would say to stay with his version because it works for him - but I really don't like the idea of yanking the SCer off again. Actually, pulling the SCer isn't so bad, it's cleaning up the mating surfaces that sucks!

Decisions... Decisions. Anybody know a shop in Detroit that can weld aluminum?

Rick Carter

Rob,
Is making the Louie/Tony setup for me with some modifications. You could ask him to make one for you. The only caveat is mine is an Andy Keel kit on an 85, yours is a DR kit on a GT. I don't know if there would be any fitmant issues. While I'm thanking people I should include you for starting this thread, with thanks again to Louie and Tony.

Tony

If i knew how to weld aluminum..or weld in general i would make you one..actually a bunch. IMHO..You need some sort of baffle/seperation below that plate Andrew and a min of 1" dia pipe/tube volume leaving it.... It will only help. Its doesnt have to be aluminum ya know.

Bill Ball

The stock breather outlet on the filler neck is super tiny, so DR's new one is an improvement. Also, on the stock filler, the passenger cam cover hose goes in there too. Amazing that it works. Remember, I never had any problem with oil out that breather until I began cruising for miles and miles at over 160 MPH. If I didn't open road race at these speeds, I could leave everything as it is and be fine.

AO

A'ight! I guess I already knew this was the way to go , and since it's all apart anyway... no time like the present. I'll see if I can find a machine shop nearby to help me put something together.

Just out of curiosity, does anyone know how much pressure we're talking about in the crankcase? Maybe it was mentioned earlier... if it was, I missed it.

blown 87

I think that is the whole thing is to not have any pressure.