Thanks for your help. Tried earthing but no joy so stripped the motor/mechanism and found the shaft was seized. Managed to get it out and cleaned and greased - had to fill some of the housing with mastic as it cracked. It is now working again but not sure for how long - grease will slowly get washed out and it will seize up again! Will have to watch out for it slowing down again. The hardest bit was re-fastening the pipe back on for the washer as the pipe had snapped. I would have thought it would have blown a fuse but it hadn't!!