The service manuel is very helpful, we where able to restore the device to its working operation again.
Text excerpt from page 2 (click to view)
KD-291R/291RC
MECHANISM DESCRIPTION
Operation
1. Motor ON
When the tonearm is moved down on the surface of the record, the feed arm ~ moves in the direction of an arrow so that SW2 turns ON to start the motor.
2. Tonearm Return
When the tonearm arrives at the end of the record, an operation as shown below is performed. Thus, the gear of the center shaft is engaged with the ring gear to start counterclockwise rotation. By the ring gear ass'y alone, the tonearm actuator moves in the direction of arrows to return the tonearm.
