just call them and ask to talk to the tech ,,,they will take care of it for you ,,i have not reinstalled mine yet to see if it works ,,but you have a 1 year warrenty on it for repair or replacement ,,i sent mine back and in two weeks i got it back ,,,i had same problem worked killer when cold but when engine was good and woarmed up it would stick ,,,
when i took mine off you could hold open the blades and see a drag mark in tb right were the shaft and blade came together ,,i also did the extra return spring and it did help but not completly