I have a previously very reliable Singer 427, and suddenly, the bobbin thread just will not be picked up. I've checked that there are no caught threads etc, and everything looks clear but am not sure where to go from here. I've checked in the manual, but but can't see the solution. Help, please?

Elisabeth, April 2011

I have a Singer 427 machine. When I thread it and start to sew the underneath thread is loopy and not even. What should I do?

Kerry, February 2014

Remove the top cover & check the gear on the right hand side of the machine.You will probaby find that the gear has sheared,common problem.

Sewman, May 2011