bmwe60525d

This one for the experts on forum....

Can someone comment on why we cannot simply remove the Crank breather filter altogether...how much oil can there really be in the form of mist from the crank air that it filters/blocks and what is the downside if this was removed.

Where would the oil go if it was not filtered/blocked by the filter.

Some of the later ones have not got the breather filter.

I understand the air it filters goes around to the inlet manifold.

When this is filter is blocked and not changed....what problems does it really cause.

Thanks in advance.

1Animal1

I can only tell you what i know through researching this on my Audi S3.... and from people who actually did remove the breather and regretted it.

First thing is, by removing the filter and disconnecting from the inlet (where deposits could form without the filter) you will remove the pressure in the crank causing a fault code and probably running issues. Second thing is if you vent to atmosphere from the crank, the smell created isn't a pleasant one, you will therefore end up reconnecting once you start to get those lovely fumes in your cabin....

I think the vent to the inlet is an omissions thing to an extent, recycling the air in the crank, cant really see it getting blocked to be fair due to the pressure...although the cars i've worked on had a one way valve which was fed by a swirled pipe to ensure no deposits get into the inlet. Oil in the inlet leading to a turbo isn't a good plan, although this depends what car you have.

Not sure if this answers your query fully

Tim

YeeeHaa

You need the crankcase breather, it is a servicable part.

I had a problem with white smoke from the exaust and oil issues until I changed it. https://5series.net/forums/topic/106...Bat+%2Bminimum

bmwe60525d

Thanks for the replies.

I decided to remove the loo roll after reading that a version of the engine m57n2 (I think) was manufactured with no filter in the housing.

I have not blocked or disconnected any piping... just simply removed the filter.
So the should be no fumes into the engine bay as the pipe still goes around to inlet as before.

I would not expect smoke from exhaust unless there is lots of oil in the crank air that finds its way to the inlet.

I have rank car for 300 miles and no problems or error codes (fingers crossed).

I read that when filter gets blocked this can have -ve impact on engine turbo (starves it of oil or something) so taking out filter should help turbo if anything.

I will report back if enything else crops up but I am not ecxpecting any unless like I said there is lots of oil in the crank air that comes around to the inlet.

Open to other peoples comments and experiences

1Animal1

Can i ask what engine you have?

Dandle

The M57N2 has a different part no. housing I would guess that there is still some sort of filter (its actually an oil separator) built into it but that it isn't a separate part like the Loo Roll or vortex filters/separators that were around before. If your going down that route you should replace the housing with the newer version not just remove the separator.

bmwe60525d

Mine is a 2004 July build e60 525d saloon
I am 99% that this is m57n

Ragtop Steve

OK, Peeps

The e60 530 dose not have a Crank Case Breather ""FILTER"" It has the Crank Case Housing but BMW did not introduce the ""Filter" in the e60 D Models. I am almost sure the 525D is the same

I did check this with my Local BMW Dealer and they confirmed thet there was No Breather Filter in place.



As for engine model numbers


520d M47N2 2005/2006/2007

520i M54 2003/2003/2004/2005

523i N52 2004/2005/2006/2007

525d M57N 2002/2003/2004/2005/2006/2007

525i M54 2003/2003/2004/2005

525i N52 2004/2005/2006/2007

525xi N52 2004/2005/2006/2007 (Left Hand Only)

530d M57N 2003/2003/2004/2005

530d M57N2 2005/2006/2007

530i M54 2001/2002/2003/2004/2005

530i N52 2004/2005/2006/2007

530xd M57N2 2005/2006/2007 (Left Hand Only)

530xi N52 2004/2005/2006/2007 (Left Hand Only)

535d M57N 2004/2005/2006/2007

540i N62N 2005/2006/2007

545i N62 2002/2003/2004/2005

550i N62N 2005/2006/2007

M5 S85 2003/2003/2004/2005/2006/2007/2008/2009

1Animal1

So what's the conclusion, take it off...clean it, and replace?

Incidently, I'm replacing my vacuum pipes at the weekend and cleaning my EGR... where is the breather located?

Dandle

Your dealer is wrong. Look at real OEM and it clearly shows oil separators for all pre LCI engines bar the 535d which had the different housing from the beginning.