As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT REPORTED REAR ENGINE WAS HARD TO START. AFTER TROUBLESHOOTING, THE LT MAGNETO WAS REMOVED. UPON INSPECTION THE IMPULSE COUPLING WOULD NOT ROTATE IN THE CORRECT DIRECTION. THE MECH WAS NOT SURE IF WRONG IMPULSE COUPLING OR SPRING TURN BACKWARD. DUE TO ONLY 36 HRS AND 1 YR 10 MO. SINCE ENGINE WAS REBUILT BY MFG. MFG INSPECTED IMPULSE COUPLING AND DISCOVERED IMPULSE SPRING BROKEN.