TOPIC: Making an Effective oil separator

Here's more on the oil separator topic. First, I went to Ebay and found the simple BMW oil separator I've been talking of. This one is the one to use, IMHO. Avoid all the other BMW stock types of these, that have a diaphragm as part of it. There are several kinds of these BMW AOS devices, you only want the simple type like this one. There is another one like this, where the in/out hose nipples point in opposite directions, that might ease install on some vehicles. In my last post I have a pic of this same AOS, and a diagram of hose hookups. I'm still trying to find a diagram of how BMW installed these to confirm the in/out design. You can see in these pics, that there is a definite baffle in the lower hose nipple. I've shined a bright flashlight into all 3 openings-light doesn't show past into any of 'em. So there seems to be a definite internal baffling to this part.

The ABS catch reservoir I made in my last post, must sit below the bottom angled hose nipple. 3/8" hose works here. Adapt this oil separator into the PCV and breather hoses as needed.

I'm also considering a new theory I have on crankcase gas ventilation. I've made up a new gizmo using lamp parts and a piece of copper tubing. I'm thinking, that if this gizmo is installed in the main air inlet duct between the air filter and TB. Situated so the slant cut opening faces towards the TB, away from the incoming airflow. Then the copper piece is a shroud that induces a pressure drop at the slant cut in the lamp tubing. 3/8" gas hose fits the threaded lamp tube well. So- the PCv valve hose is pulled from man.vac. nipple, the nipple gets capped,. The PCV valve hose goes to inlet on the separator, outlet hose from separator goes to the gizmo on the air inlet duct. .

MY theory is that this could (I hope) serve to give more active, positive crankcase gas flow out of the crankcase, while preserving the manifold vacuum too. This idea has yet to be tried and tested. I found the lamp tube and brass nuts in a well-stocked hardware store. The rest of it I had on hand.

Further- a small air inlet scoop might be added to the breather hose connection to the air inlet duct or air filter box. This could add some positive pressure to the breather side, while the gizmo helps give a pressure drop to the PCV. And it is all related to air inlet duct air flow, which in turn is related to engine RPM/load.

The whole idea is to kill the "PCV valve vacuum leak" and more effectively remove oil and water vapor and condensation from the crankcase. The lamp parts for the gizmo were about $2.00, the BMW oil separator was under $10.00 shipped on Ebay. Add hoses, the ABS reservoir bottle I made, and whatever else is needed to hook it all up--one could probably make this whole deal for under $40.00.

Tracy G

Sorry for the necro, but also higher crankcase vacuum promotes ring sealing, a common-ish practice for ~2500HP dragsters to have dedicated PCV/oil sep. pumps due to the extreme amount of blow-by they experience.

This whole thread is really a waste of time for anyone pursuing it.

Once the PCV is eliminated from the system, this also ends the issue of water in the oil, for the humidity entering the engine CAUSING the presence of water ALSO ends!

And, in order for the separator to work, there has to be flow through the device. This is ALSO terminated when you put a cap on the PCV.

ANY water in the oil will be a CERTAIN indicator of a leaky head gasket, as there is nowhere else the water can come from.

Think about these things, gentlemen. When addressing ANY issue, think about all aspects before deciding on a course of action, or whether any action is indicated.

Ron