As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) TRANSMISSION RECEIVED FOR 1,500 HOUR INSPECTION. TOP CASE REMOVED AND 10 TEETH FROM THE INVOLUTE SPLINES WERE BROKEN WHICH IS NOT IN ITSELF AN UNUSUAL OCCURRENCE. WHEN A NEW REPLACEMENT WAS OBTAINED FROM BELL THE LOCKWIRE HOLES FOR THE FILLER CAP AND CHIP PLUG HAD NOT BEEN DRILLED. A SECOND CASE WAS ACQUIRED FROM BELL AND IT WAS CORRECTLY DRILLED.