Cut open Mann PF1055

[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. Of course we have known for a long time 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, which isn’t surprising.

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...