Hello Judy,
The only thing I can think of for a serger jamming is if the cotton is jammed at the hook, the smallest piece can cause the machine to jam, as a last resort I would suggest that you take all cottons off and force the balance wheel backwards, the worst you can do is is break the needles.
Ken
Ken Dourof
April 2007
I can answer this question...
I have a Kenmore Serger 3/4 and the wheel is locked. Help??