dragged this anchor out the shed again.... Compression tested, and am getting good compression. Got a drill on the flywheel and am getting no spark whatsoever (plug is fine - my seagull makes it give off a lovely bright spark).
I took the flywheel off, the magnets seem pretty strong, all wires intact, and everything underneath was cleaned up with scotchbrite and put back together... still the same. I previously swapped the CDU, and it made no difference.
I am getting perfect continuity down the HT lead.
WTF do i do next?
I think i'll buy a boat*
*I think i'll buy a boat and then spend the rest of my life trying to afford to keep it