While into a project the cut out motor stops cold while X, Y and Z continue to do their thing with no problem. When I tap the rear of the machine the motor will restart and either complete the carve or stall again. Eliminated the cover safety cut out switches. Problem started after I serviced machine, new Y motor, and replaced motor brushes. Disassembled and double checked and cannot find anything visually wrong. Cut out motor has 658hours on it. I also see the LED display adding division signs in place of letters (eg., Ca++in+ patt+rn) since service. Can someone give me some troubleshooting ideas. Am I due for a new motor? Did I crunch something during servicing?