As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING A NR 2 ENGINE CYLINDER CHANGE DUE TO A CRACK THE INTAKE VALVE SPRING INNER AND OUTER WERE FOUND BROKEN. NR 4 CYLINDER ROCKER COVER REMOVED TO ASSIST IN ASEMBLING ROCKER ARM PIN. NOTICED INTAKE OUTER VALVE SPRING BROKEN. NR 6 CYLINDER ROCKER COVER REMOVED, INTAKE OUTER VALVE SPRING BROKEN. REMOVED THE REMAINING 9 ROCKER COVERS AND FOUND NO VALVE SPRINGS BROKEN.