Needs help w/ diagnosing and hopefully repairing of a DEC Tape Drive

[Ali]

In my continuing quest for a 9-track drive I got my hands on DEC TSZ07-CA w/
a narrow SCSI interface that was supposedly "tested working". On arrival to
me I found it wrapped in a thin layer of bubble wrap w/ some broken piece of
Styrofoam thrown in for "packing". 

As one can imagine the drive did not farewell. The outer desktop housing is
cracked in multiple places but still serviceable. The drive itself came with
parts rattling on the inside. I opened it up, cleaned things up a bit, and
put things back together so that now the drive powers up, starts self test,
and then errors out w/ a "50 - Motor Fault" error.

I have checked the wires and reseated everything that I can see. I've also
cleaned all the sensors, blown out the dirt, etc. etc. The problem persists
so I am going to assume a component was damaged in the shipping. I ran the
tests indicated in the tech manual and I get the following results:
generally the supply motor starts to turn but stops even before making a
full revolution. Incidentally if I manually turn the reel it turns fine and
the tape securing arms open and close appropriately. When running the dx
tests sometimes I can get the uptake motor to spin up at full speed and once
even had the supply motor spin up at full speed. Per the tech manual if
restarting the system does not make the problem go away the next step would
be to replace the motor....

Google fu has not turned up much - so before I declare this a very heavy
paper weight anyone have any ideas? Thanks!

-Ali