Crankcase Breather Oil Separator

[colingtv6]

Guys,
The oil separator has been removed from my 75 Turbo.

Does the Q4 have one? And if so is there any reason for removing it?

Also does anyone know if a turbo oil separator is different to a N/A one?

Col.

[Steve Webb]

Hi Col,

Q4's have a cam breather / oil seperator, which is fed back to the inlet tract just after the air filter. I think all new cars by law now have to have a 'closed loop' system which is fed back into inlet, rather than just a clovered vent.
As far as I know, turbo ones are the same as NA ones.

As for benefits of not having one, I'm not sure there are any. Well none that I can think of.

Here is a pic of the breather in the Q4

[colingtv6]

I've got a spare TS one that I might try.

The only bit that is missing form the TS one is the take of for the peirburg valve. For some reason this is taken off the bottom of the oil separator on the 75 turbo. Is the Q4 the same?

My peirburg valve has been tee-ed into the pipe just downstream from the AFM.

I have noticed that the 155 16V has no separator, I presume though there mut be a non return valve though to stop a backfire into the inlet manifold from ignigting the crankcase vapours :shock:

[Steve Webb]

Not sure why the 75 Turbo would have the Peirburg valve takeoff at the oil separator, the Q4 just has it plumbed in between airfilter and turbo. The difference might be because the 75 has am AFM, and the Q4 a MAP.

Never had a 155 16v so can't even begin to speculate why it doesn't have one. But there will probably be something like a brillo pad stuffed into the pipe between cam/crank breather and inlet to act as a flash arrester.

I'd go with leaving your peirburg valve connected where it is, and just installing the separator from the TS and seeing how things go.