As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PROPELLER WAS IN FOR CALENDER TIME OVERHAUL. AFTER DISASSEMBLY, FEATHER ASSIST SPRING WAS FOUND BROKEN IN FOUR PIECES. THIS PROBLEM WOULD CAUSE THE PROP TO NOT FULLY FEATHER AND/OR SURGING OF RPM DUE TO NOT HAVING ENOUGH SPRING PRESSURE.