Just joined in never too late.
1) check brushes ,blow out top of motor through
Cover plate at the top turning motor with hand
Sand brushes with light sand paper
2) If Magnet comes on then you have Power to circuit board. Unplug remove power. Remove 4 screws from cover plate where power cord comes in. Unplug black and white wires going to motor. Hook power directly to black and white wires. Motor will run if not theres a short on the top cord or the field cord is burnt. But then you would smell burnt wires. So check for short
But before you do that the black and white wired you unplug from circuit board put you tester on AC voltage and hook up press green to start assuming power is on. MAKE YOUR CIRCUIT BOARD IS INSULATED (not touching metal) circuit board can short. when you press the green start you wound get 120 volts which means your circuit board is good if not getting any power there then board is bad. I dont do boards so I cant say. Board is around $125. Thanks for letting me post my 2 cent wort
Please feel free to cal