After being airborne for approximately 35 minutes, the engine began to lose power. The pilot picked an oil well lease site for a precautionary landing and while descending to the intended landing spot, the engine lost and regained power and then finally quit. The pilot entered autorotation and on landing the aircraft bounced, resulting in the skid gear spreading and the mast rocking. Sole occupant pilot was uninjured CADAORS 2012C2510