Service Instruction No. 1125 D
Alternate Crankcase Parting Surface Sealants
Supersedes Service Instruction No. 1125C
October 17, 2008
All Lycoming opposed cylinder engines.
TIME OF COMPLIANCE
During engine assembly.
The use of POB No. 4 Perfect Seal sealant (POB) and silk thread has been used generally for sealing finished parting surfaces that do not employ gaskets. This practice has always been satisfactory when correctly applied. However, we have tested and approved General Electric Company’s RTV-102 and LOCTITE-515 as alternate sealants which may be used at field service overhaul facilities where trouble may have been experienced in applying POB and silk thread.
Get It Exchanged
Use our Engine Exchange Program to order a new, rebuilt, or overhauled engine to experience more airtime and less downtime.