Is this machine the 318EL, if so there is only two reasons why the motor runs but does not turn the chain, the first is you have lost tention between the three belvile washers under the head of the allen screw holding the drum on, they create friction between the drum and the output shaft ( they are hardened dished washers fitted face to face to create what is in efect a compression spring) the secobd reasons is you have lost some teeth from the nylon gear which is fitted to the end of the output shaft against the motor gear ( pt no. 508043702 ) unfortunatly you need to remove the sprocket and alloy shaft houseing to see this, and the two motor halfs to replace it, over loading is the main cause of failure.
Husqvarna man
January 2010
howtomendit.com for free repair help, information and advice.
