The drive drum is not rotating despite there being good drive to the flywheel. ie the belt is in good condition and drive is being transferred to the flywheel under the right hand cover looking from the front of the mower. So the seems to be slippage in the drive mechanism within the drum. How does the drive get transferred and what is the solution?

Tetley1, April 2017

Bingo, just had the same problem, although these models differ slightly in the way they work, mine is a 35x check the larger of the two drive wheels and see if there is a clutch mechanism fitted, there is a slip ring in the centre of the large cog that is designed as a clutch in a car would work, to save the motor straining and burning out this is designed to spin when under strain, if that. Sticks in the off position the blade will just spin, simply manually turn the centre ring around till it slips back into mesh with the blade, before you can fix something you must have a reasonable idea how that item works, Colin, Wales, Honestwelsh

Colin Harvey, July 2017