Roland RE-501 Chorus Echo Repair Service. This tape delay was sent to me by a customer stating that the tape does not turn. Please do whatever is necessary.
The first thing I noticed was the tape. It looked very worn and the adhesive strip was already loosening. This loop was not of good quality. The adhesive strip was not only stuck at an angle (cosmetics). It also overlaped so that the glue rubbed off the tape head every time.
The motor needed servive. The bearing was totally sticky. Disassembling time. If you plan to do that, you should have the right tools to remove the locking rings. And you should be very patient and gentle. Clean, lubricate and reassemble everything well.
And since it was a restoration, I renewed all the felts, cleaned and lubricated all the bearings, cleaned, polished and demagnetized the heads, cleaned all parts leading to the tape, replaced the electrolytic capacitors and looked at everything more closely. I noticed a black spot. There used to be a wire bridge, which was probably short-circuited like a fuse. Boom!