What was found
WHILE TAKING OFF, A RPM LOSS OF ABOUT 100 RPMS WAS NOTICED. THE ACFT RETURNED AND LANDED. WHILE TAXING BACK IN THE RPMS WOULD VARY WITHOUT ADJUSTING THE THROTTLE. THE POWER LOSS WAS REPORTED TO MAINTENANCE. WHILE RUNNING THE ACFT TO TROUBLESHOOT THE PROBLEM THE ACFT WOULD MISS OCCASIONALLY AND NOT MAKE FULL RPM. THE LT MAGNETO WAS REMOVED AND OPENED AND THE ELECTRODE FINGER WAS FOUND TO BE COMPLETELY DETACHED FROM THE DISTRIBUTOR GEAR. THIS MAGNETO SN IS BEFORE THE SERIAL RANGE THAT MFG HAS COVERED UNDER SN SB1-15. THIS IS THE PROBLEM THAT SB ADDRESSES, BUT THIS MAGNETO WAS NOT COVERED. THE FACTORY TORQUE SEAL WAS STILL ON THE MAGNETO, SO IT DID NOT HAVE A REPLACEMENT GEAR INSTALLED IN THE FIELD.