[cam-alot]

I have no drive and thus think the clutch has gone. Any idea on how to fix this would be very welcome.

[smud6ie]

Norlett drives are usually engaged and disengaged by a jockey wheel which presses against the drive belt .If you have no drive then the belt may be broken or the clutch cable may need tightening to make the jockey wheel press harder into the belt.
If this is working ok and you can see the drive pulley to the rotor turning then something is sheared in the rotor drive housing.
It may help if you posted which model of Norlett you have and what you can see is turning
smud6ie