Mann PF1055 Filter with Integrated Bypass

[JHZR2]

My 1981 MB 240D was due for an oil change. I decided to try to cut apart the cartridge filter, a Mann PF1055/1, which is the standard filter for the Daimler-Benz OM61x series of engines. Those familiar with these cars have known that other than some Turkish-made Fram filters, the rest were filled with cotton gin waste or similar. I wanted to cut apart a recent one to see if that was still the case. It is.

Enjoy.

Paper media glued to the end caps for the full-flow section...

And the bypass section. Yes that is sticks and hard bits of outer leaves or shells from cotton or a similar plant.

This stuff is kept out of the oil flow by something that is, say, the equivalent of landscaping fabric - not as thick or rigid as filter media, perhaps actually a bit tougher in terms of tear resistance, and probably flows well. Since the leaves and sticks are so large, this fabric need not have tiny filtering capability.

Given that the OM61x engines are amongst if not the longest lived, most robust automotive engines mass produced, it seems like the leaves and sticksare just fine. It's interesting that such a thing is allowed though...

 

[rubberchicken]

I wonder if anybody has cut open the bypass filters such as the Amsoil BMP-90 or similar. Are they filled with similar stuff ?

 

[Popsy]

That is an interestingly made filter! Thank you for the c&p.
I wonder why they are using such a "crude" media and not some kind of finer and more refined version of it. Cost maybe ? Or is there another reason for it ?

 

[JHZR2]

Originally Posted by Popsy
That is an interestingly made filter! Thank you for the c&p.
I wonder why they are using such a "crude" media and not some kind of finer and more refined version of it. Cost maybe ? Or is there another reason for it ?


My suspicion is no need. Dense, tortuous layers I suppose is the real need, so these big items are like boulders, easily filtered, so why remove them? The cost to get pristine cotton fluff would be a complete waste since the big particles crest no risk or concern.

 

[DoubleWasp]

Wow. It's a Steampunk oil filter.

It's worked for decades, so whatever.