AD 56-06-01

56-06-01 CONTINENTAL: Applies to O-470 Series and E Series Engine Serial Numbers Below Excepting Any Remanufactured Engine Shipped From Continental Motors Corp. After May 1, 1955, and Engine Serial Numbers Designated "Exceptions."

Compliance required as soon as possible but not later than July 1, 1956.

To prevent serious engine damage in flight, the following must be accomplished:

1. Replace present piston pin assembly with piston pin assembly P/N 539467 in the following serially numbered engines:

Engine Model O-470-A, Serial Nos. 41258 to 41679, 40015-2-A, 40021-2-A, 40028-2-A, 40045-2-A, 40054-2- A, 40074-3-A, 40110-3-A, 40125-3-A, 40154-3-A, 40168-3-A, 40176-3-A, 40177-3-A, 40203-3-A, 40204-3-A, 40242-3-A, 40264-3-A, 40267-3-A, 40293-3-A, 40334-3-A, 40371-3-A, 40418-3-A, 40424-3-A, 40438-3-A, 40444-3- A, 40485-3-A, 40494-3-A, 40567-3-A, 40579-3-A, 40581-3-A, 40601-3-A, 40619-3-A, 40647-3-A, 40651-3-A, 41008-3-A, 41025-3-A, 41032-3-A, 41033-3-A, 41038-3-A, 41039-3-A, 41068-3-A, 41094-3-A, 41109-4-A, 41175-4- A, 41181-4-A, 41187-4-A, 41189-4-A, 41196-4-A, 41251-4-A, 41254-4-A.

Engine Model O-470-B, Serial Nos. 50001 to 50256. Exceptions - 50189, 50241, 50245, 50246, 50247, 50250, 50251, 50252.

Engine Model O-470-J, Serial Nos. 45001 to 45533. Exceptions - 45520, 45521, 45525, 45529.

Engine Models E-225-4, E-225-8, Serial Nos. 30163 to 30715.

Engine Models E-185-8, E-185-11, Serial Nos. 22200 to 22269.

Engine Model E-185-9, Serial Nos. 6128 to 6135.

In addition, replace piston pin assembly, P/N 535145, with piston pin assembly, P/N 539467, in any O-470 or E Series engine that was overhauled in the field and in which it is known that P/N 535145 was installed at time of overhaul.

(Continental Motors Corp. Service Bulletin No. M56-2, Supplement No. 1, dated March 12, 1956, further discusses this subject.)

2. Replace present oil pump gear assembly with oil pump gear assembly P/N 539525 in the following serially numbered engines:

Engine Model O-470-B, Serial Nos. 50076 to 50256. Exceptions - 50189, 50241, 50245, 50246, 50247, 50250, 50251, 50252.

Engine Model O-470-J, Serial Nos. 45001 to 45533. Exceptions - 45447, 45448, 45456, 45457, 45462, 45463, 45466, 45468, 45473, 45474, 45481, 45484, 45489, 45491, 45494, 45495, 45500, 45503, through 45514, 45516, 45519, 45520, 45522, 45523, 45525, 45526, 45528, 45529, 45532.

3. Replace present exhaust valve with exhaust valve P/N 539449 in the following serially numbered engines:

Engine Model O-470-A, Serial Nos. 40001 to 40673.

Engine Model O-470-A, Serial Nos. 41001 to 41679.

Engine Model O-470-J, Serial Nos. 45001 to 45489. Exception - 45487.

(Continental Motors Corp. Service Bulletin M56-2, dated February 14, 1956, further discusses this subject and offers special discounts for replacement parts ordered prior to July 1, 1956, from bona fide Continental aircraft engine spare parts distributors.)