As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
"ALERT" MAGNETO IMPULSE COUPLING PAWL RIVET (RIVET ATTACHES PAWL TO IMPULSE HUB ASSEMBLY) FAILED ALLOWING PAWL TO WEDGE IN MAGNETO DRIVE GEAR CAUSING FAILURE OF DOWEL ON CRAKKSHAFT DRIVE GEAR RESULTING IN COMPLETE STOPPAGE OF ENGINE. IN ADDITION, THE MAGNETO FLANGE BROKE AWAY AT THE HOLD DOWN BRACKET.