What was found
DURING ROUTINE INSPECTION, DISCOVERED THAT AFTER MAIN ROTOR TRANSMISSION OIL WAS DRAINED, OIL LEVEL INDICATED FULL. OIL LEVEL SIGHT GLASS REMOVED. INSPECTION OF THE OIL LEVEL INDICATOR REVEALED COATING WITH LEVEL MARKINGS HAD SEPARATED FROM THE METALLIC BACK PLATE. THERE IS A RING OF HOLES ON THE CIRCUMFERENCE OF THE INDICATOR. THE HOLES IN THE LEVEL MARKING COATING AND THE BACK PLATE WERE NO LONGER ALIGNED. THIS CONDITION WOULD NOT ALLOW OIL TO DRAIN FROM THE SIGHT GLASS. THE SIGHT GLASS IS THE ONLY MEANS TO DETERMINE THE OIL LEVEL IN THE MAIN ROTOR TRANSMISSION. IMPROPER SERVICING OF THE TRANSMISSION PRESENTS A POTENTIAL FOR SERIOUS PROBLEMS IF LEFT UNDETECTED.