Unscrew blade bolt. Now, in the words of the Haynes manual - 'pull the blade boss off the shaft'. Now, back in the real world .....
You will probably need a puller. Re-install the blade bolt about 8 turns. Position the puller so the jaws pull o what remains of the boss, and the central bolt bears on the blade bolt. Chances are great force will not be required.
If there is not enough of the boss to grip, you will have to cut it off - a reciprocating power saw with a metal cutting blade will sort it in a few mins.
Be aware that a blade strike capable of shattering the boss may well have bent the crankshaft.
phil_saunders@bigfoot.com
Phil Saunders
July 2008
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