But when I went to the parts manual to look up a replacement, it only shows the Gear Box (Ref 23 of the Front Wheel page in my book). I doesn't show any of the parts that make it up. Not the lube port screw or this rubber ring. Anyone have a good part number for it?
I'll have to measure the housing's groove dimensions and try to find a generic o-ring of the appropriate size if I can't find the proper part.

Thanks for any pointers any of you can offer!
Bob750