Turn input shaft manually or engage motor and it will take over. That's how they were supposed to work but we have a few issues with it due to the fact that they are 60 years old. With motor engaged, output shaft runs at 1 rpm.
Although they are new in the box, the washer in the clutch has dried out and the motor will no longer engage the shaft.
We sell these for manual use only. If you get the motor assist to work, you're ahead of the game. Knobs pictured in movie are NOT included.
1/2" Shaft Adjuster