Sewing Machine: Motor won't run
Make sure that you plug in the foot pedal completely. Replace the foot pedal if it's defective. If the motor buzzes but won't run, check for a jammed needle. Replace the motor if it's defective.
These repairs may help solve your Sewing Machine problem:
Replace the sewing machine motor
The motor drives the belt, which spins the hand wheel and upper shaft. Replace the motor if it won't run when activated by the foot pedal.
Replace the sewing machine foot pedal
The foot pedal sends power to the motor. The foot pedal controls the speed of the motor, which drives the belt and hand wheel. Replace the foot pedal control if it fails to send power to the motor or control motor speed when activated.
Replace the sewing machine needle
Examine the needle regularly and replace it when it's dull or bent. A dull or bent needle causes skipped stitches. When the machine skips stitches, check the needle and replace it if it's worn or bent.
Clean the sewing machine
Clean lint and debris from the shuttle race every 3 months because it often attracts lint and dust. Clean the feed dogs at the same time because they also attract lint and dust. Clean those areas more often when using the sewing machine regularly. Oil the sewing machine after cleaning.