Ha. When I disengaged the drive and ran the motor the nut thingy had shot along the spiral and dissapeared. Found it, moved it back, and re-engaged.
So the problem is the cold.
You need to adjust the sensitivity of the motor stop control.
Apparently some GB1s have open and close sensitvity dials.
Ours didn't. The adjustment is a wing nut on top of the unit. Tighten it up; ours took 3 turns.
Job's a good un.
Paz
December 2010