He's not posted since July last year.
Hopefully he's ok, and just hasn't needed any help recently.
Oh, and as for the pump burning one brush faster than the other. It's actually quite common for a DC motor to burn the positive brush down, faster than the negative brush, or the other way round, I forget which now.
o.k, it's just that I wanted to change the thread title as it is quite useful to people now !
Could start a new thread and reference this one I suppose.