He fixed her! My sweetie took all morning and patiently took apart my machine, cleaned the brushes, contacts and commutator. We put her back together and she ran better, but still not tip-top. He then took apart the foot peddle and adjusted the wire contact mechanism and voila! She roared! I've never seen her move so fast!
In detail:
The motor was very easy to get to...only one screw to release a metal bracket that covered the compartments that held the brushes. He left the motor in the machine because he could get to everything without taking it out. (Singer was so thoughtful and effecient that way.) The brushes were worn, but only about 1/4 gone...pretty good considering her age and use, so we didn't replace them. There was a lot of carbon soot on everything, so he carefully used Q-tips dipped lightly in rubbing alcohol and cleaned all the points of contact. The commutator had some hardened stuff on there, so he took very fine sand paper and gently cleaned the crud off and also wiped up any leftover grit with more Q-tips. (He didn't want grit to get into the bearings.)
We put her her back together and she ran, but still kind of slow and hessitantly, so he took apart the foot peddle. This was something that we probably should have done first, but we really felt that the brushes were the problem. Just as well...the motor needed inspection and cleaning anyway. Inside the peddle there is a horseshoe shaped wire/metal piece that moves forward when the peddle is pressed down. When it moves, it makes contact with the electrical wires and starts the machine. Over the years, this metal piece had bent back and was not making a good contact any longer. Once that was adjusted, the machine ran like the wind.
Thanks for everyone's input. I hope that my post will help others with their machines. I could definitely do this project on my own if I ever need to. It wasn't hard at all. It just took a little time and patience. Now, I'm off to work on my "new" Redeye treadle that arrived during the holidays!
~ C.