What was found
BUTTERFLY IN WASTEGATE FOUND WARPED AT EACH 100-HOUR INSPECTION. WARPED WASTEGATE AND WORN BUTTERFLY AND SHAFT CAUSE THROTTLE BINDING. BUTTERFLY MUST BE STRAIGHTENED FOR PROPER RIGGING. ON SOME AIRCRAFT, BUTTERFLIES COME OFF OF SHAFT AND BIND THROTTLE. COMMON TO ALL 'F' AND 'FX' MODELS. SUBMITTER STATED WASTEGATES NEED TO BE REPLACED AT 900 HOURS MAXIMUM TIME IN SERVICE.