Best way to clear the vacuum path: remove the sanding belt and collection bag. Use an airhose to blow compressed air through the opening where the bag attaches to blow out anything that may be in the airway. After blowing through the outlet, check around the rear of the drive pulley for any wood that may have to be picked out. Reattach everything and try it again. If it still doesn't work, the vacuum is driven by a fan on the end of the armature. You'll have to take the case apart and check that to see if the fan blades have broken off or the fan has come lose from the armature.