I was happily sewing along, when my needle snapped for no good reason. It appears that the metal ring round the bobbin case that turns as you sew does not turn any more. It can be helped along and will make a revolution or so before getting stuck again. I have cleaned out a lot of lint and have opened it up, but I can't see where might need oiling/cleaning specifically. The belt looks ok; I think the problem is more with the metal turny bit rather than the belt but I may wwll be wrong.
Hello Fran,
I suspect that the nylon gear under the raceway in the bottom of the machine has broken up, very common on the 400 series especially considering it age, take the bottom off and have a look, then take the top off the machine and have a look at the nylon gear because that may be broken, it can be fixed without an expensive shop repair, I have all the instructions, email me below with your findings.
ken
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