Hi.
If rotating the knob on the left hand side does not solve your problem chances are one of the clutch belts or the clutch itself is slipping.
You can pick up a clutch for approx £15.00 on Ebay
& then you can purchase a manual to show you how to strip machine down & fit the clutch again readily available from Ebay UK for £7.50
Its not that difficult to repair.
chris
August 2007