What was found
WHEN TIGHTENING THE CONTACT ASSEMBLY SECURING SCREWS ON THE DUAL MAGNETO DISTRIBUTOR BLOCK, IAW THE SERVICE MANUAL INSTRUCTIONS TO A TORQUED VALUE OF 20 TO 25 LBS.-IN. THE EMBEDDED NUTS START TO PULL OUT IN 2 OF THE 4 LUGS. THE ASSEMBLY THAT MOUNTS ON THE DISTRIBUTOR BLOCK IS FLUSH MOUNT IN 2 LOCATIONS, AND IS SLOTTED IN THE OTHER 2. IT APPEARS THE EMBEDDED NUTS START TO PULL THROUGH IN THE SLOTTED LOCATIONS AT LESS THAN 20 LBS.-IN.THE OPERATOR IS USING THE REQUIRED D-3000 MAGNETO IGNITION SERVICE CHART FOR TORQUE VALUES. THIS MAGNETO (DUAL MAGNETO) INSTALLATION IS AVAILABLE IN A VARIETY OF AIRCRAFT/ENGINE INSTALLATIONS. THIS OPERATOR IS NO LONGER USING THE DISTRIBUTOR BLOCK, BECAUSE OF THIS REOCCURRING PROBLEM. THE DISTRIBUTOR BLOCK APPEARS TO BE TO SOFT.