Oil Tank Breather plumbing question

[billjam]

For my '88 Carrera that is about to get a 3.6 transplant, I am looking for ideas on how to deal with the oil tank breathers.
Because the 3.6 engine has ITBs, the usual connections to the air filter box aren't available. I can add fittings to the ITB aircleaners, but prefer to find another solution if possible.

In the pic below ...
A used to go to the original 3.2 aircleaner
B is where the large hose from the engine breather connects
C looks like a vent from oil tank via one-way valve D to control valve E
(I have no idea what the purpose of E is.)
E had a vacuum hose (F) from throttle body and another larger hose from port G to the original inlet manifold.

If I delete valves D and E, can I connect A and C to a catch tank or a combined fitting at the aircleaner without ending up with oil everywhere?
Some pics of catch tanks might be useful if anyone has pics or links. I've searched but didn't come up with anything relevant.

[Elombard]

On Mine I have removed C, D, G and F and plugged at C and at the nipple on the back of the TB on the 3.2. SO you can plug C. (emissions control stuff)

I believe you will keep B hooked up similar to the stock 3.2 into the block. You can run A to a catch bottle. If you go to Jegs or summit there is a large selection of breathers to choose from.

Also, the two hoses that go through to the charcoal canister are removed (as is the canister on my car. I plugged the smaller of the hose up near where it enters the tunnel underneath with no ill efects so far. It goes to the fume vent system on the gas tank.

[KTL]

Here's a good topic on catch can installations.

can I see oil vent catch cans

C can be plugged. It's for the PCV valve emissions thing which seems rather redundant to me. The engine case breather is already PLENTY of Positive Crankcase Ventilation!

D, E, F, G can be ignored as they are often not even present on cars that do 3.2 Motronic installations in earlier cars.

A goes to your preferred catch can installation.

[billjam]

Thanks guys. It is handy to know that most of this stuff can be deleted.
I did a bit more reading last night and found some more info here on catch cans. Ebay also has heaps of them all different sizes, so I don't even have to waste hours making one.
I guess I was doing my usual over-thinking the problem

I will be retaining the existing fuel canister vent and vacuum hoses for now.

[dipso]

You can't see because everything is black. But I go from the cranckcase to the neck, from the neck to a hole in the engine tin, right up front of the right bank of cylinders.
Basically it vents down to the exhaust.

[Uncle]

Along the same lines is anyone making an oil cap with a breather on it?

[Deadeye]

Here is what I did

[billjam]

Originally Posted by Uncle

Along the same lines is anyone making an oil cap with a breather on it?

That makes sense! If the cap was replaced by something with a filter on it and the breather connections on the tank were capped, you wouldn't even need the catch can.
It can't be that simple, can it?

[KTL]

If cap was replaced with a breather filter, you could cap the breather port A. B must remain as is because the engine needs to puke itself into the tank. That B hose spits a LOT of oil.

One thing to keep in mind with A location, it will on occasion spit some fluid. Most often its water vapor. But if the tank is slightly overfilled, it'll spit pure oil. If you're a complete nimrod like me and overfill the tank by several quarts (because said nimrod forgot to drain engine sump while car was off the road during winter) then that A location, or your tank cap breather, will puke a LOT of oil.

In my case, since the A location was attached to the stock location on throttle body rubber elbow like Porsche designed it, the oil gets puked right into intake manifold and engine swallows/pumps it nicely out the exhaust as blue smoke. The resulting James Bond smoke screen is impressive to say the least! And your muffler gets filled with whatever amount of oil the engine couldn't turn into smoke.

So my point is, when you eliminate the "closed system" by putting a breather on it? If the oil tank has to puke, it is going to go all over the engine compartment. Thus the reason for the catch can arrangement.

[billjam]

Kevin,
Your arguments for oil tank breathing back to intake or air filter sold me on doing the opposite!
The last thing I want is puddles of oil in my CF air cleaner housings oozing oil all over my lovely ITBs and everything else below them.
I also don't want the risk of filling up my Magnaflow mufflers with oil either.

I am going to cap the small pipe C and put a small oil breather filter connected directly to A so that it sits high up in the space behind the hinge above where the emissions valve thingy (E) is currently located.
I do see the point of putting a catch can (connected to A), but I'm happy to take the risk of puking some oil out through the filter if things don't go to plan. I figure the volume of the filler neck and the 1" hose up to the filter can effectively be my catch can.
And in the unlikely event of oil spilt in this area due to a "nimrod" moment, it is no big deal to clean up with a pressure washer (which is pretty much what I need to do when I change filters anyway).

[Uncle]

I am looking into the cap thing as I want to run an oil return line from the turbo back to the tank via A and have no C option.

Want me to let you know how I get on with it? Local speedshop thinks he can get me something.

[Elombard]

Bill, I think I read about lots of attempts to do a filter breather as you describe and it blows lots of oil mist out and keeps the engine bay oily and messy. I believe a proper breather has a chamber that allows the oil to drop out before the vapor leaves so the engine compartment gets less oily. Might want to research before you do it like that.

[billjam]

That's a very good point Erik, thanks for bringing it up.
I can imagine the whole engine bay gradually becomming quite messy if oil vapour is continually being discharged through the small breather filter.
It looks like a proper catch can is in my future!

[rsscotty]

We like using the Petersen breather tank that has nice internal baffling, and mount it on the rear frame rail in the left wheelhouse. One of the threaded bungs is plugged, and the other uses a -12 union fitting. If you machine the threads off of the -12 union the breather hose slips right on with a clamp. The tank has a nice clamp with two mounting flanges.

[KTL]

How does the nice Peterson tank breathe? Is there a filter or screen under the removable lid, sort of like a rain hat setup on Webers?

[Deadeye]

When running my 3.2 with the set I use in the photo, I had very little oil accumulate in the catch tank. The drain at the bottom makes it easy to draw off. I transplanted a 3.6 into the car over the winter and have yet to see if it catches more or less oil. I really don't get an oil oil fog in the compartment by the way.

[KTL]

I agree the catch can doesn't collect much of anything under normal conditions. My catch on the racecar pretty much always drains water and some tan goop, which is oil-air-water mix. The goop volume is like a teaspoon at most.

Only reason I mentioned the puke situation is for consideration when there's a problem- like when a dope like me overfills the tank.