I came across this website today and at the bottom of the page there is a area that you can bring up depending on what you need to know! Lots of information. Maybe this might help specially if you are going to rewire. I read they used the service manual for servicing the Featherweights when out in the field. If you do take it to someone make sure they have worked on Featherweights before. I have a person in my area that knows them inside and out. He cleaned and serviced my first one and did a great job. Maybe one of the wires just needs to be reconnected? Did you notify the person you bought it from? Maybe a little refund is in order to help with the other expense!! Hope you find some helpful info on this site.
http://www.singer-featherweight.com/...dard_main.html