Unfortunately the drive motor is underneath the head assembly, so you can't see it without more disassembly of the drive. The servo motor moves the heads via a

Unfortunately the drive motor is underneath the head assembly, so you can't see it without more disassembly of the drive. The servo motor moves the heads via a rack and pinion gear. There's a (bad) photo of the motor on page 52 of the manual: http://bitsavers.trailing-edge.com/pdf/diablo/81503-03_Series_30_Disk_Drive_Maintenance_Jul78.pdf http://bitsavers.trailing-edge.com/pdf/diablo/81503-03_Serie...