I just ran my new 2353’s and I for about the first 3 minutes the cycled threw the gears great! But after the motors started heating up due to age it would only cycle forward. I cleaned the faces of both motors and lubed up armature shafts and gears and went to run it again. Only now it cycles threw all 3 positions but will only run forward. If I cycle it to reverse and move the lockout lever it still won’t run in reverse.
FEC - I do not think so. You would have smoke from the insulation on the e-unit coil wires.
I wonder if the e-unit plunger and contacts need cleaning. Radio Shack still sells a TV tuner contact spray (they call it something else now) that you can spray into the e-unit to clean it out without disassembling it.
Maybe not ‘burned up’ but it does need work.
Try cleaning the plunger, drum, & fingers with denatured alcohol applied with tooth picks and cotton swabs.
If that don’t work you may have to rebuild it or replace it.