What was found
UPON INSTALLING A SHAFT INTO A ROCKER WITH INADEQUATE TOLERANCE LIMITS, NOTED BINDING IN THREE CLOCK POSITIONS. WITH PRUSSION BLUE, FOUND THAT THE SHAFT IS FORMED IN AN ELIPTICAL OR, MODIFIED TRI-ANGULAR SHAPE WITH REDUCED WEAR SURFACE AREA DUE TO INCONSISTANT DIAMETER OF THE SHAFT. ALL 24 NEW SHAFTS DISPLAYED THE SAME MACHINING RESULTS. THE HIGHEST PRESSURE POINT WAS AT THE NARROWEST CONTACT POINT. GALLING OF THESE SHAFTS APPEARS TO BE CONSISTANT WITH REDUCED WEAR SURFACE AND CROWNING OF THE SHAFT. WHILE OTHER FACTORS MAY BE ATTRIBUTED TO THE CAUSE OF THE PREMATURE SHAFT FAILURE, THE REDUCTION IN SURFACE AREA IS CONSISTANT WITH ACCELERATED DECOMPOSITION OF BEARING SURFACE. AIRWEST AIRCRAFT ENGINES SUPPLIE