As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(AUS) NR 4 CYLINDER EXHAUST VALVE LIFTER DAMAGED DUE TO BREAKING AWAY OF THE HARD FACING ON THE BOTTOM OF THE LIFTER. INVESTIGATION FOUND SIMILAR DAMAGE ON NR 1 CYLINDER EXHAUST VALVE LIFTER, NR 5 CYLINDER INLET AND EXHAUST VALVE LIFTERS, AND, NR 2 CYLINDER EXHAUST VALVE LIFTER. THE CORRESPONDING CAMSHAFT LOBES WERE ALSO WORN. EXHAUST VALVE LIFTER P/N SA 646277. INLET VALVE LIFTER P/N SA 628488.