As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT STARTED AIRCRAFT NORMALLY AND DID RUN UP WITH A BAD MAGNETO CHECK. PILOT DID NOT FLY AIRCRAFT AND RETURNED TO HANGER. AIRCRAFT WOULD NOT RESTART. IMPULSE COUPLE DID NOT MAKE ANY NOISE, TIMING WAS WAY OFF. FOUND IMPULSE COUPLE SPRING BROKEN A TURN AND A HALF FROM OUTER END.