What was found
THIS HELICOPTER IS THE THIRD FACTORY NEW AIRCRAFT WE RECEIVED FROM THE MANUFACTURER WITH THIS ISSUE. ALL THE ROCKER ARMS AND PUSH ROD CAPS WERE FOUND TO BE SCORED DURING A PRECAUTIONARY INSPECTION. BELOW IS WHAT WAS ENTERED INTO THE AIRCRAFT LOGBOOKS. "REMOVED ALL ROCKER ARM AND PUSH ROD ASSEMBLIES FROM ENGINE FOR INSPECTION. FOUND ALL 8 PUSHRODS P.N. 15F19957-30 WERE GALLING AGAINST THE ROCKER ARMS P.N. 17F19357. TAGGED PARTS AS UNAIRWORTHY AND SENT TO ROBINSON HELICOPTER FOR EVALUATION. RECEIVED NEW ROCKER ARM AND PUSH ROD ASSEMBLIES P.N. 17F19357 (8EA), 15F19957-30 (8EA) FROM ROBINSON HELICOPTER COMPANY. WASHED PARTS IN MINERAL SPIRITS AND DRIED AS NEEDED. PRE-LUBRICATED ROCKER ARMS, VALVES, VALVE ROTATOR CAPS, ROCKER SHAFTS AND PUSH RODS IN ACCORDANCE WITH LYCOMING SI 1059E. ASSEMBLED ENGINE, TORQUED AND SAFETIED ROCKER COVERS AS REQUIRED. PERFORMED ENGINE GROUND RUN UP, OPERATION AND LEAK CHECK WERE GOOD." WE BELIEVE THIS IS BEING CAUSED BY A LACK OF LUBRICATION AT THE ROCKER ARM-PUSHROD MATING SURFACE DURING THE INITIAL RUN UPS AT THE LYCOMING FACTORY OR DURING THE DE-PICKLING PROCESS.