Starter issues need help please

Actually hitting a starter with a hammer can cause it to work, at least temporarily. As stated above, the main contact can become worn and be right on the hairy edge of not working and just a little tap will get 'er going. I had a my boat (GM engine) do the same thing over the summer. It wouldn't start (in the middle of the lake) until I hit it with a hammer. Turns out the brushes were so rusty they wouldn't move at all and were barely making contact. They actually disintegrated as soon as I touched them, needless to say I replaced the starter.