Grrr.
MrsF has been moaning one of her sewing machines isn't winding the bobbins. I know nothing about them, but I've replaced a motor on one of her freehand quilting machines - it's like bikes in our house, she has more machines than I have bikes, and some are DI2 - i.e. electronic computers with touch screens.
Anyway, I've just removed half a million screws to undo the covers and, as I'm moving the machine, I 'pull' on the big wheel, and it moved to a different 'position'. Call MrsF over, why does it do this ?. Oh.... she then realises that machine needs the main wheel pulling out to engage the drive for the bobbin winder, her other machines don't need this step. She'd 'forgotten'.
So, nothing was wrong with it, and I've half a million screws to put back in.
Double Grrr