When you say the power Vis spins continuously do you mean the final drive peg can actually be seen going round and round? Or, can you just hear the motor running? If it is the latter then the gearing inside has stripped from the final drive or the "bell end" of the motor has lost its grip on the spindle.
Just for clarity, this is the power Vis
https://www.ebay.co.uk/itm/Land-Rove...MAAMXQjwVQ-hWa