The clutch gets driven by the same pin that drives the impeller. The second hole in the shaft, seen in your picture, is not used when there is a clutch. That hole would be for a shear pin to drive on the propeller directly, with no clutch.
Bill the clutch is not driven by the impeller pin the 2 holes are outside the pump.. one for the clutch and one for prop without clutch as I have said ..
Removing the old seal is not a neat and tidy affair for me. I use hammer and punch to beat in the rim of seal so I can grab on it with nippers and bite off pieces. There probably is a neat and clean method other have discovered, but. not shared. Not a difficult job, just time consuming.
The real problem is that the old hard seal has worn a groove in the prop
shaft so a new seal will not work or last.
Louis
It seems to me the lower unit illustration is for later type lower unit
not KD4 type.
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