Yesterday I removed one of the banjo bolts that serve as oil injection ports on the housings of my 20B. In the bottom of the threaded bore I noticed a slotted plug with hole in center. I wondered if the slot had something to do with maybe distributing the oil to the tip seals.  It looked like it was threaded in; so in my curiosity, I took a screwdriver to screw it out.  It turns, but doesn’t appear to move up or down.  What is it there for, and did turning it do anything?  I want to make sure it doesn’t possibly move inward and contact the tip seal.

BTW; the hole is threaded 10mm, 1.25 pitch; and a plug bolt should be a max of about 12mm long.

Al