rebuilding starter

[truoss]

I bought some brushes at ACE hardware, shaved them to size and stuck them in my big red starter. The first time I tired it, it ran for a a little bit, and then stopped. I took it apart again, and saw that I hadn't insulated the wires well enough. So, I did it all over again. Then I bolted it back onto the big red, and it started a few times, but it got weaker and weaker. Now it won't turn over anymore. What is wrong? I did use a car battery, which puts out too many amps, but that shouldn't make it die that quick, should it? Are the brushes not good enough?
I have also noticed that the plate where the brushes are attched is getting weak. Is there a place I can buy a new plate and brushes and springs? I looked in the dennis kirk catalog and they just offer the brushes....for almost $40.
I inquired about rebuilding the starter, and that would cost about $60. I really hope I don't need to pay that. Does anyone have a used starter for sale?

[bentwrench]

could be alot of things. carbon build-up in the grooves between the "bars" on your comutator, GENTLY with a small sharp point clean out these grooves a small pick or brad nail will work. just scrape lightly until black is gone. if this doesn't work it will need to be tested for shorts or burn outs by a rebuild shop. Have you tested your solenoid?? maybe getting hot after repeated attempts.