Hello Ellen,
If your machine is picking up every thread and making stitches it is unlikely it will need retiming but if you want to at the end then I can send you details, go through this step by step even though you may have gone through it before, when you thread the machine make sure the presser foot is up and make sure the thread goes completely between the tension discs, make sure you do not have a burr on the end of the needle because that will pull the thread back up, make sure the bottom tension is set enough to just about be able to pull the thread through with some resistence, if it feels tight turn the screw on the bobbin case anti clockwise, test sew with the various top tension numbers and see what results you get.
drivewithken@blueyonder.co.uk
Ken
drivewithken@blueyonder.co.uk, January 2008