model? lot of model use the small tri shape washer between inner and outer wheel.this washer must be fitted with high part towards inner wheel.to do this you must loosen the small screw on inner wheel and ensure correct position .easiest way to put machine on left side to ensure washer stay in place.refit screw and see that inner wheel only turn small distance when loosenig,if not remove washer and refit in next slot on shaft.refit screw and check again.make sure to put drop of oil on shaft where handwheel turn on shaft.if bobbin winder does not work it is possible that it need a new tyre.also oil lightly on winder shaft,they tend to get sticky.hope info is off some help
johan, June 2012
