Sorry the needle is not going down, - Sewing Machines

Needles will not go down for:
1. The lock on the hand wheel isn't locking. Try this
a. Loosen the lock like you're going to wind a bobbin.
b. Loosen screw that is on the side of the lock. (sometimes front)
c. Tighten the lock just like when you're going to sew.
d. Tighten the screw that is on the side of the lock.(sometimes front)
e. Turn hand wheel by hand. Did the needle rise and fall?
2. The drive belt isn't moving the shaft.
a. Remove the top of the sewing machine.
b. You will most likely have to remove the panel on the end where the hand wheel is.
c. Turn your hand wheel to see if the belt is moving the shaft or is it broken?
d. Replace if you need to. (look at wear). Loosen the motor.
e. Make your motor run (foot pedal) slowly. Tighten the belt by pushing on the motor while it is running. When the motor is placed at the right place the motor will be moving with very little drag. (This will need a listening ear)
f. At this point tighten motor and retest for the speed and drag.