DURING CRUISE FLIGHT IN SNOW SHOWERS THE ENGINE SUDDENLY LOST POWER. SUBSEQUENT EXAMINATION OF THE PLANE BY COMPANY MAINTENANCE PERSONNEL REVEALED THAT THE FUEL VENT TUBE LOCATED ON TOP OF THE LEFT WING HAD BEEN BENT BACK ALLOWING SNOW TO BECOME IMPACTED THROUGH THE CURVE OF THE LINE. THIS WOULD RESULT IN FUEL STARVATION TO THE ENGINE.