Don't know your lathe but suspect that there is a failed shear pin in the drive to the power shaft, near to where it is is coupled to the Norton gear box.

If the Feedshaft (when selected) rotates under power, then the problem lies within the Saddle.

If the Leadscrew (when selected) does not turn under power, then the problem lies in the drive INTO the gearbox.

If drive to the Leadscrew is selected, it is likely that the drive to the Feedshaft is disconnected. This is to prevent conflict between the two feed modes of imparting movement to the Saddle.

Rally stupid question: you have selected one of the forward or reverse positions for the feed selection?

My lathe allows the gearbox to be: Rotated in the same direction as the Mandrel : Neutral (Disengaged) : or Rotate in the opposite direction to the Mandrel. Might be worth checking!

Suggest that you start tracing the drive from the gear on the back of the Mandrel, until you find a failed key / keyway / gear lacking some teeth / failed shear pin, When you find something that no longer rotates when the mandrel is rotating, that is likely to be the problem area.

There should be a key in the worm within the Saddle that engages with the Feedshaft to power the Saddle for facing and Sliding.

Howard.

Edited By Howard Lewis on 03/09/2018 17:58:40

Has the feed worked since you have owned the lathe or has it never worked? Are you fully conversant with the controls for the feed?

Mike