What was found
INSTALLED 3-BLADE PROPELLER IAW STC SA 4529NM. STC MAKES NO MENTION OF PROPELLER GOVERNOR. AFTER 3 HOURS OF OPERATION, PROPELLER BEGAN SURGING 100-200 RPM FROM 2,400 RPM. AFTER NUMEROUS TESTS, DETERMINED THE EDO AIRE (GARWIN) PROPELLER GOVERNOR CANNOT SUPPLY THE VOLUME OF OIL REQUIRED BY THIS PROPELLER. REMOVED THIS PROPELLER AND RETURNED TO THE ORIGINAL 2-BLADE HC-C2YK-1BF/F7666A PROPELLER. OPERATES NORMALLY AFTER 8 HOURS.