Wobbly needlebar on a Pfaff 46.
 

I finally found a belt the right size so the motor doesn't scream anymore. This is a machine at my church where we have a quilt group. I want to get one of the resident machines sewing so I don't have to take mine. The New Home has no guts. The Touch and Sew's bobbin spring won't stay down and the Pfaff was screaming. I oiled it and replaced the belt. The machine will occasionally sew straight, but generally the needlebar wobbles back and forth and produces a slight zigzag effect. I took off the nose plate and the top cover. I can follow the path of the connectors to the needlebar, but it all looks okay. This is a very simple machine - probably the plainest ZZ machine I've ever seen. No bells and whistles. Nice machine, though a little noisy as it sits in a plastic case even though it is a metal machine. I know ZZ machines don't sew a perfectly straight seam, but this is far beyond that - close to 1/8". Any ideas?