I have resurrected this old thread in the interests of keeping the topic as condensed as possible. As a matter of interest, I have not re-read any of the posts, but I am merely adding details of my latest experiences. As you guys may recall, there were some problems in obtaining new filters, and in the process of trying to purchase some units from the States, I got stung by a fellow in Texas by the name of CHANO, possibly trading as TX Benz Hoarder, Corpus Christi in Texas. That cost me $176.00. I then established contact with a company in the UK, but they sent me M117 450 Filters. So, back to the States.
I found a company selling two versions of the 6.9 Oil Filters, with a price difference of about 60%. I opted for the 'genuine' and more expensive variety, but I suspect that they sent the 'after market' version, but charged genuine. Anyway, I left it at that. Okay, to the gist of continuing the thread.
GB showed evidence of a persistent slight leak from the filter, but I was a bit lazy in getting on top of it, until one day I decided that it was getting too much. Thanks to Oversize discovering an internal 'O' ring at the base of the filter, I decided to make certain that I would have a replacement on hand - I did have an old and unused canister on hand. I should also point out that the oil filter kit supplied (genuine), did not contain the 'O' ring, but the large one only, as well as the two copper sealing washers. When I finally drained oil and removed filter, I found that the large retaining bolt showed evidence of roughness in the area of the internal 'O'ring. See the picture attached (hopefully).
You can see the two bolts side by side. You will also note that the genuine 6.9 bolt is solid, whereas the replacement that I had on hand from a 6.3 engine, does have 'breather' (?) holes, and is hollow. I decided to use the 6.3 bolt in preference as there were no signs of marking on the bottom of the bolt. Questions I have are these:
1. Should it be deemed appropriate for me to have used the 6.3 bolt, and
2. Why should there be any difference in the design features of the two bolts.
Incidentally, the leak has been eliminated, and there certainly do not appear to be any oil pressure issues. Regards Styria