Gen charging Q

[hardtimes]

I'll try to picture the device that's on top of my generator.
If it shows, I'd like to know if anyone has seen such and how is it adjusted ?
My amp gauage shows negative, until I rev to an unpleasant rpm, then it will show charge. In your opinion, does this 'regulator' thingy need changed out or
what to get the generator charge to more output ??

The gen has a THIRD brush. I've moved it 2 to 3" back/forth slowly..no change ?

no pic.....?
THANKS FOR INPUT...
Ok guys, some egg head showed me what I was doing to upset machine and no pic....
I do not think that I infformed you correctly, in that this is now a 12V system from original..if that makes you change your advice.
From pic, do you recognize silver device / cutout ? Maybe junk needs changed ??