OK, I know I'm going to get flamed for this, (forgive me Father, for I have sinned), I modified the original MB design.
I really don't like putting a dry, or even a pre-oiled filter in place at oil change time, and then firing the engine up, and listen and wait for the oil pump to fill the oil filter housing before going to 3 bar. I really feel this is wear that is going on that can be avoided with little effort. (Easy Boys, you don't know where I live, and I'm armed!, magnum bean flip, and a mean BB gun, so read on).
First thing is to put the correct "O" rings on the filter head stem, (no, they are not the same, the lower one as installed is 6mm x 10mm, and the upper is 7mm x 11mm. Don't believe it, take a dial caliper and measure the stem).
Now for the major modification, I took my dead blow hammer and knocked off the the filter housing head from the stem over a piece of carpet to prevent damage to the head, (careful, rap evenly on each side). Take the stem and drill and tap the upper stem to fit a sealed set screw to avoid problems with the the by-pass, ream the top housing to fit easily over the stem, be careful here and do not change the depth of how far the stem will fit into the filter head.
That's the modification, place the stem in place in the engine, fill about 1/2 full with the oil of your choice, and install the filter, slowly. Top off and install the filter housing head with new "O" ring for the head, and fire the old girl up. In my experience, you should see 3 bar in seconds.
Please understand I'm not posting this to sell anything, I'm just trying to keep my 617 alive a little longer, and maybe yours. OK, I'm done, let the flaming begin. And brother, if you have a better idea, I want to hear it.
Thanks
Okieone