Dear Mr. Day,  Saw your posting on MMD today and humbly suggest you
take some digital photos of the beast to enable one of us to help.
I'll bet this was either a conversion done by (or kit sold by)
Ragtime Piano Co. of Ceres, CA.  There was also an outfit in Alabama
turning out custom nickelodeons in the late 1970s-80s.  Whatever it
is (whomever made it into an automatic) it sounds to me as though
it is fixable.

If the roll stalls and runs erratically I wonder if the problem is
not more than a linkage glitch.  It seems to me if the motor was bad
it wouldn't run at all unless the driver motor is pneumatic (which
I doubt).  Could be that the rewind/play/repeat mechanism is
malfunctioning in some way.  Hope this helps some!

Eric J. Shoemaker
Tacoma, WA