Tim's right. The inner and outer idler shaft bushes are dimensionally identical, but the scrolls are mirror images of each other. Just like turning a nut over, the thread still runs the same way. So a crankcase side bush fitted to the timing cover will pump the oil into the dynamo cavity. Just needs one part number error in the aftermarket quality replacement parts market and the whole Wa**el based supply chain is tarred with the same *eked brush and the same wrong bush comes from all major suppliers.
An inner timing cover to hand has a bush with a scroll like a big left hand thread. Anticlockwise leads the groove inwards towards the crankcase from the dynamo cavity. Idler gear shaft needs to be relatively unmarked, they sometimes wear with distinct annular ridges.
Cork washer under the dynamo drive sprocket is not a seal as such, more a way of eliminating endfloat on the idler shaft. Grease before fitting to prevent burn on dry start up.
Swarfy.
