Starter motor questions - rebuild

[Jezza_hr]

Judging from what I've been seeing, the solenoid contacts are a more common issue than the brushes, but I was a little confused as to why the sliding mechanism would work but not the motor itself, since my assumption was they are both on the same circuit and one shouldn't work without the other, but then I guess one has to work to make the other function, since you don't want the motor turning without the slider being engaged first.

I've gone ahead and ordered a pair of new copper solenoid connectors as they're only £5 shipped from eBay. If that doesn't do the trick, I guess it will be the bushes.

Thanks for the help Jondee