Hey Elaine,
Day late and a dollar short, that's me. The Singers are the best in the world, they'll last longer than a human as long as you're cleaning and oiling between garments/quilt top. I'm on my second Singer, I just bought it in November. I do a lot of garment sewing (I'll post a pic of the four bridesmaids dresses I did a couple of weeks ago next week) and I do a lot of blanket making with fleece for my kids and grands and the storm damaged. I do a lot of sewing, it's my sanity.
I bought the new Singer to replace or assist the Simplicity machine I've been using (about 3 million miles or so..) for the last 20 years. I never had to have the Simplicity serviced. I kept it clean and oiled with good sewing machine oil NOT 3 n 1 oil. It eats a machine up and slows it down. The belts are not hard to change and that's what it sounds like with your machine, if it were a gear, as Tim said, you wouldn't be getting it to do anything.
Trust Singer repair, but not the sales people. Try to find someone that does the repair separate from a sales floor. I've never been afaid to take a screw out of a piece of equipment. It can't hurt if it's not working well anyway, right? lol lol
OOOOOOh dear, got on that to soapbox, didn't I. I believe in having good working machinery. I didn't get a Singer with all the bells and whistles. I go the Singer Ingenuity at Walmart for about $239. It matches me, gives me some nice finishing stitches, it's built for quilting, and I love it. When I win the lottery I'll buy one with all the bells and whistles. I wonder if it will be as much fun?
Sharon
Sharon