What was found
(CAN) DURING THE BOROSCOPE INSPECTION OF THE ON-CONDITION PROGRAM, SPECIAL EFFORT WAS MADE TO INSPECT THE EXHAUST VALVE AS WE HAD FOUND A PREVIOUS VALVE OF THE SAME PART NUMBER IN POOR CONDITION. THE NR 2 CYLINDER EXHAUST VALVE WAS FOUND SEVERELY ERODED 1/3 TO 1/2 OF THE WAY ACROSS THE DIAMETER OF THE VALVE STEM WHERE THE STEMOF THE VALVE MEETS THE HEAD OF THE VALVE. THE PROBLEM APPEARS TO BE A METALLURGICAL PROBLEM OR A DEFECT IN THE MANUFACTURE OF THE VALVE. THE VALVE WILL BE REPLACED NEW. ALL OTHER ASPECTS OF THE ENGINE WERE INSPECTED FOR A CAUSE OF THIS PROBLEM AND NONE WERE EVIDENT.