66-20-04 LYCOMING: Amdt. 39-277, Part 39, Federal Register August 18, 1966. Applies to Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines Equipped With AC Oil Filters Except O-320- A, -E Series, Engine Serial Number 16128-27 and Higher; O-320-B, -C, and -D Series, Engine Serial Number 6217-39 and Higher; IO-320 Series, Engine Serial Numbers 2110-55A, 2113-55A and Higher; O-360 Series, Engine Serial Number 9346-36A and Higher; O-540 Series, Engine Serial Numbers 9770-40, 9800-40, 9803-40 and Higher; and IO-540 Series, Engine Serial Numbers 2831-48, 2835-48, 2840-48 and Higher.
Compliance required within the next 50 hours' time in service after the effective date of this AD, unless already accomplished.
To prevent further failures of oil filter adapter gasket, P/N 74904, accomplish the following:
(a) Replace gasket, P/N 74904, with gasket, P/N 76691.
(b) Inspect the stud, cap screws, and tapped holes in the accessory housing mounting padfor proper length or depth, as applicable, in accordance with Lycoming Service Bulletin No. 307 or later FAA-approved revision. Replace studs and cap screws of improper length and retap holes of insufficient depth as necessary in accordance with Bulletin No. 307 or later FAA-approved revision.
This directive effective August 27, 1966.