Hook is not rotating

Similar to the FAQ "Machine wont pick thread up from bobbin at all" however, if the hook is not rotating, we know the problem will be a split or cracked gear maybe under the bobbin area or bottom half of the machine, or the drive from the machines top shaft to the vertical drive shaft - Replace gear as required and retime machine.

Also check the top horizontal shaft for a broken gear at the top of the vertical shaft - Replace gear as required and retime machine.

These sewing machine gears are very reasonably priced and can be replaced as a DIY job.