Opened up the shell. I don't see any pinched wires or scorch marks. Everything is connected. I did see a black wire that was tight but after loosening it, made no difference. Loco still hums when giving the track power and flips the circuit breaker on my Z1000.
Can you guys look and see if I'm missing something? Disregard the popped out black arm in the first photo. I fixed that before testing the loco.