Ok managed to sort this today. Been stripping out an 8v at the scrappies all day and took the motor from that. Did the swap which thankfully was easy but I still had the same problems. The only other thing it could be was the stalk so I tried that (managed to rob that from the donor 8v too) and Bingo it works!!
I still can get my head around whats in the stalk that can control the timing of the motor though as it just seemed to be a load of copper contacts?
Anyway, job sorted, hope this can be of use to someone in the future
