64-16-05 LYCOMING: Amdt. 765 Part 507 Federal Register July 10, 1964. Applies to O-320, O-340, O-360 and O-540 Series Engines Equipped With AC Fuel Pumps, AC 5623-467 (Lycoming P/N 74082), AC 5656880 (Lycoming P/N 74082) and AC 6440152 (Lycoming P/N 74798), and to IO-320-B1A, IO-360-A1A, -B1B, HIO-360-B1A, -B1B and IO-540-C-B5 Engines Equipped With AC Fuel Pumps, AC 5623466 (Lycoming P/N 73973) and AC 5656696 (Lycoming P/N 73870), Except for Recent Production Engines and Remanufactured Engines Listed in Lycoming Service Bulletin No. 298, Which Have Already Incorporated the Modification.
Compliance required within 25 hours' time in service after the effective date of this AD unless already accomplished.
To preclude the possibility of engine oil being drained overboard as a result of oil seal failure in AC light weight fuel pumps, modify AC pumps with part numbers listed herein in accordance with the instructions contained in Lycoming Service Bulletin No. 298.
This directive effective July 10, 1964.