I'm thinking my machine was made around 1987. I bought a 66 plastic bobbin and the machine sews like a champ now. It more than likely needs to go in for a servicing because when I got it, I got it for free from the side of the road, and it looked like it had been stored in a barn for several years. Even had a mouse nest in it. I cleaned it as best as I could, and it sews great, sounds smooth as silk. The stitch selectors move with ease, and all the different stitches do appear to work. The bobbin winder at first didn't do anything, but I was able to work it lose, and now it winds the bobbin to the correct amount, then kicks the bobbin out.