After a little think, I lifter the playfield and I can see whats going on now.
When one of the switches has been switched "ON" and stops the motor, the next time the motor either goes up or down, the motor runs in reverse until it hits a lever from the switch, stops and goes forward again.
Is this whats its supposed to do and I just need to adjust the lever ?
Or should the motor not run in reverse at all ?