McMillen Auger

I just recently acquired a used McMillen post hole auger, what are some things that I should look at before I use it? I have one tooth on the auger that I know needs some attention. It's really loose and appears that maybe a roll pin or something is missing. There is a little dish/cup to the top of the tooth where it slides into the end of the auger but there is a bunch of dirt in there that I need to clean out so I can see how it is supposed to be secured in there. I know I read on one of the old forums on here that one should check/change the oil in the drive motor gearbox so I will do that as well. Anything else that I need to be skeptical of or check close before I use it? I have a cattle yard fence to replace and it will be about 100 post holes so I want to make sure it is good to go before I start.

Thanks

McMillen Auger