COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Teledyne Continental Motors Piston Engines AD/CON/57 Amdt 1 Oil Scavenge Pump Gears 10/90 Applicability: TSIO-520B, BB, D, DB, E, EB, J, JB, K, KB, N, NB, UB and VB engines as detailed in TCM Service Bulletin M90-6. Requirement: Replace scavenge pump gears P/N 635334 and 639388 in accordance with the requirements of TCM SB M90-6. Note: FAA AD 89-24-01 R1 refers. Compliance: Effective 4 October 1990; Within 500 hours time in service or at next access to affected parts, whichever occurs first. Background: This amendment and FAA AD 89-24-01 Rev 1 reflect advice received after the original issue of these Directives. The advice indicates concern with the integrity of scavenge pump gears is limited to certain part number gears. This advice is reflected in TCM Service Bulletin M90-6.