I have a Singer 99 that has the brush cap broken off on the motor, and I can't get the screw part of it out to put another one in. Does any one have any ideas of how to get it out? I tried using a small screwdriver to see if I could move it at all, and it doesn't move. Someone suggested that I just super glue the cap on. The spring is there in the hole, and the machine does work, even with the cap off. I have just taped it on at the moment as I didn't want to do anything permanent that can't be undone if anyone knows how to get the broken part out. Just what does the brush and cap do in the motor anyway? Help please!!!