If you don't have a impact wrench, you can remove the spark, slowly lower the piston with the pull rope, feed a short peice of nylon or cotton rope through the plug hole to fill up cylinder. bring the piston back up against the rope with a 15mm box end wrench, turning the nut (counter clockwise ).when it feels solid, give the wrench a fair rap and it should come off easily.
mdmarble1957
January 2010
You first need to remove the clutch assembly, the nut on the face of the clutch is 15mm, the clutch is spun onto the crank left hand thread, if you have an impact gun this is the best way to remove it, if not you need a 15mm socket on a speed brace, keep tapping it round with a hammer against compression ( clockwise) it will eventually unthread from the crank, the drum will then just pull off ready for a replacment. The standard sprocket is a spur sprocket .325 pitch 7tooth
pt no.503088702
Husqvarna man
January 2010
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