Service Instruction No. 1280 D

SERVICE INSTRUCTION NO. 1280 D

DATE:

July 20, 2021

SUBJECT:

Rotator Type Intake Valves

MODELS AFFECTED:

All Lycoming engines built with the conventional, large head intake valve No. 73117 including: IO-360-A, -C, -D; AIO-360-A, -B; HIO-360-A, -C; LIO-360, TIO-360-A, IO-720-A, -B, -C; VO, IVO, TVO, TIVO-540; IGO, IGSO-540, IO-540-A,B,E,G,K,L,M,P,S; TIO-540-A,F,J,N and LTIO-540-F,J,N. Engines modified in accordance with factory approval no. 2158 to incorporate rotator intake valves are not subject to the modification described herein. In addition to the engines mentioned above, all O-360-J2A and O-540-F1B5 engines are eligible for rotator type intake valves.

TIME OF COMPLIANCE:

At owners discretion

REASON FOR REVISION

Added engine models O-360-J2A and O-540-F1B5. Updated publication format and part numbers. Added IO-540 and (L)TIO-540 models back into Models Affected that were omitted from prior revision.