oil separator and nonreturn valve question - The Unofficial BMW M5 Messageboard (m5board.com)

Ruppy · 21st October 2009, 12:22

Hi guys.

Does anyone know what inside the oil separator. I opened mine. It was completly empty. It is normal?

Other.

What is the right direction of the non return valves unther the butterflyes? Every butterfly have a non return valve in a idle air line. The ICV feed the idle air to the buterflyes through this valves.
This valves have 2 side

one is metal and the other is plastic. No any arow or some direction signs on it.
This valves not realy 100% "non return" just one direction is easyer to go through the air the the other. I dont untherstand how does operate.

mottati · 21st October 2009, 20:11

my oil separator is also empty, i believe it's supposed to be!

No idea on the other issue however.

Tomba · 21st October 2009, 23:22

Quote:

Originally Posted by Ruppy

Hi guys.

Does anyone know what inside the oil separator. I opened mine. It was completly empty. It is normal?

Empthy,.. There is some kind of diafragma below fastened with a hex. bolt. The oil is supposed to drain below the diafragma to the dipstick in the sump and not sucked by the engine vacuum into the cumbostion room. Use fuel or other liquid to see if it spools (use a can to pick up the fluid so it won't fluds into the engine).

Quote:

Originally Posted by Ruppy

What is the right direction of the non return valves unther the butterflyes? Every butterfly have a non return valve in a idle air line. The ICV feed the idle air to the buterflyes through this valves.
This valves have 2 side

one is metal and the other is plastic. No any arow or some direction signs on it.
This valves not realy 100% "non return" just one direction is easyer to go through the air the the other. I dont untherstand how does operate.

If you put vacuum on 1 side and you can't get vacuum, this side belong to the throttle bodies (air should folow the direction of ICV - > Throttle body= right direction). Maybe the non return valves are there to get a more stable vacuum in the idle strip, you use them because you only want a vacuum in the throttle body and no influence of others. With the non return valve each cilinder is seperatly and not connected which each other. Synchronosation the throttle bodies would be lots better, there is less influence of the other vacuum from other cilinders. Maybe it has more to do with it. You only see them on S38B38 and S50B3X and S54B32.

Ruppy · 22nd October 2009, 00:42

Hi Tomba

I removed every valves just clean out. I am not shure the former owner removed or changed this valves.
Direction....is not an easy question because this valve is more less similay in both direction. I can look through this valves with my eyes.
Only inside the valve visible a small rubber "pin" , If i blow through (with my mouse) i can't fell difference.

The butterfly sync is realy was necessary....because my car so old and the butterflyes worn a bit. (the closing positions are missaligned) I done it carefully. Now every butterfly open in a same position, and the vacuum is setetted to in each cyl based on a description. Around -0.3bar( vacuum)