Hello Rachel,
If the machine moves perfectly with the bobbin case out then the chances are there is a small bit of thread stuck round the raceway, you will have to have a really good look for it, when you put the black bobbin case back in there should be hardly any movement, there should be enough gap between the bobbin case and the silver bit on the side for thread to pass through, if there is too much movement it will jam, you can undo the two screws on the right hand side slightly and push the bar over then tighten up.
Ken
drivewithken
May 2010
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