What was found
(CAN) FLOAT EQUIPPED AIRCRAFT IN CRUISE AT APPROXIMATELY 2,000 AGL, PILOT NOTED AN IRREGULAR SOUND FROM FRONT OF AIRCRAFT. NOISE CEASED AFTER WHICH THE PILOT CONTINUED TO A NEARBY LAKE AND LANDED. 6 OF 12 VIBRATION ISOLATORS HAD PULLED THRU THE BACK OF THE SECURING EYE BOLTS WHICH ATTACH THE RING ASSEMBLY TO THE CYLINDER HEADS. RING RE-SECURED. MINOR DAMAGE TO LEADING EDGE OF TOP COWL AND FACE/TRAILING EDGE OF PROP.