AD 2023–17–04 Replaces AD 2022–04–04 

The FAA is superseding Airworthiness Directive (AD) 2022–04–04 for certain Continental Aerospace Technologies, Inc. (Continental) Model C–125, C145, IO–360, IO–470, IO–550, O–300, O–470, TSIO–360, and TSIO–520 series engines and certain Continental Motors IO–520 series engines with a certain oil filter adapter installed. AD 2022–04–04 required replacing the oil filter adapter fiber gasket (fiber gasket) with an oil filter adapter copper gasket (copper gasket). This AD was prompted by reports of two accidents that were the result of power loss due to oil starvation. This AD requires replacing the fiber gasket with a copper gasket or a stainless steel embedded within polytetrafluoroethylene gasket (stainless steel PTFE gasket). This AD also revises the applicability to include Continental model engines equipped with an F&M Enterprises, Inc. (F&M) or a Stratus Tool Technologies, LLC (Stratus) oil filter adapter installed. The FAA is issuing this AD to address the unsafe condition on these products. 

The new AD (2023–17–04) is effective October 26, 2023.

Supplementary Information 

The FAA determined that additional model engines are affected by the unsafe condition and also discovered that certain model engines, with permold type crankcases, were inadvertently included in the applicability paragraph of the NPRM, which the FAA removed in the SNPRM. In the SNPRM, the FAA proposed to require replacing the fiber gasket with a copper or stainless steel PTFE gasket. The FAA also proposed to revise the applicability to include Continental model engines equipped with an F&M or a Stratus oil filter adapter installed per Supplemental Type Certificate SE8409SW, SE09356SC, or SE10348SC. In addition, the FAA also proposed to include the revised service information. The FAA is issuing this AD to address the unsafe condition on these products. 

Required Actions 

Before accumulating 50 flight hours after the effective date of this AD or at the next scheduled oil change after the effective date of this AD, whichever occurs first, remove any F&M or Stratus oil filter adapter fiber gasket from service and replace it with an oil filter adapter copper gasket, part number (P/N) AN900–28 or P/N AN900–29, or a stainless steel polytetrafluoroethylene gasket, P/N ST07, as applicable, in accordance with the Compliance Instructions, paragraph 6., pages 6 through 10 (including all detailed instructions for Figure 5 through Figure 16), of Stratus Tool Technologies Mandatory Service Bulletin SB–001 Rev C, dated June 16, 2022. 

Special Flight Permit 

A special flight permit may be issued in accordance with 14 CFR 21.197 and 21.199 to permit a one-time non-revenue ferry flight to operate the airplane to the nearest location where the maintenance action can be performed provided that the engine oil pressure and engine oil temperatures are in their allowable ranges and there is no noticeable increase in engine noise. This flight must be performed with no passengers on board. 

For the full AD, download the PDF here.