Check the stator wires. I had this happen and they were shorting out on the motor under a heat shield. You diffently have a dead short somewhere between the switch and the motor. Also, unplug the wires one by one coming off the motor and that will tell which ones you need to trace down.(unplug one, turn switch on. If blows, plug back in and go to the next one) Hope this helps!
Eric, May 2020