The woodruff key holding the diecast boss to the shaft didn't shear, got a slight dinge on one edge from the shaft. The diecast pins on the boss loacting the blade did shear. And when I saw that I thought "Hey, nice feature have weak pins that shear if the blade hits something rather too immmovable". So bought new boss and blade fitted 'em, vibration hell...
Oh no you don't, see above. 3/4" dia crank bent 10 to 15 degrees from true. Had to cut it off right against the oil seal and prise the oil seal out before just managing to get the crankshaft down the bearing sleeve.