# STC SA3-674 - Type: Supplemental type certificate - Status: Current, Reissued - Holder: D'Shannon Products Ltd., United States - Description: Installation of Lycoming O-360-A1D engine and McCauley 2D36C14/78KM-4 or Hartzell HC-C2YK-1A/7666-2 propeller in accordance with Doyn Aircraft Drawing List for Model 1700 conversion dated May 6, 1964; for Cessna Model 175B: Atlas Aviation Oil Cooler Installation dated September 12, 1967, is required. - Applied: July 21, 1961 - Status date: July 14, 2011 - Product: Aircraft, Single-Engine - Certification basis: Part 3, Part 21 - Data sheets: [TCDS 3A17](https://openairdocs.org/tcds/3A17) - Certificate PDF: https://openairdocs.org/files/sha256/d6/00/d600ba19c23872876040b824d5c3b1681c1b32b2ca68a1922baaca0f76183522 - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/54DE227D58951D8A862578EF00466407.0001 - DRS record last changed: December 6, 2025 - Page: https://openairdocs.org/stc/SA3-674 ## ADs that name it (2) - [AD 82-07-02](https://openairdocs.org/ad/82-07-02): Engine Crankcase Breather · Lycoming O-360-A1A engine and Hartzell HC-C2YK-1B/7666A-2… (Avcon Industries STC SA1324CE or 14 others). Effective Apr 8, 1982. Named in the applicability - [AD 69-15-03](https://openairdocs.org/ad/69-15-03): Muffler Assembly · Lycoming O-320-A1A, A1B, A3A, A3B or Lycoming O-320-B1A, B1B… (D'Shannon Products STC SA135CE or 8 others). Effective Aug 20, 1969. Named in the applicability ## Approved models (3) - Cessna Aircraft Company 175 ([TCDS 3A17](https://openairdocs.org/tcds/3A17)) - Cessna Aircraft Company 175A ([TCDS 3A17](https://openairdocs.org/tcds/3A17)) - Cessna Aircraft Company 175B ([TCDS 3A17](https://openairdocs.org/tcds/3A17)) ## What the certificate says Read from the PDF's text layer, without the form's printed wording; the layout is lost and the order can differ. The PDF is the record. This certificate issued to Part 3 of the Civil Air Regulations. Installation of Lycoming O-360-A1D engine and McCauley 2D36C14/78KM-4 or Hartzell HC-C2YK-1A/7666-2 propeller in accordance with Doyn Aircraft Drawing List for Model 1700 conversion dated May 6, 1964; for Cessna Model 175B: Atlas Aviation Oil Cooler Installation dated September 12, 1967, is required. For Cessna Model 175B, Serial No. 17556895. Registration No. N8195T only is eligible. Compatibility of this modification with other previously approved modifications must be determined by the installer. D’Shannon Products, Ltd. 1309 County Road 134 Buffalo, MN 55313 3A17 Make : Cessna Model : 175, 175A, 175B Date of application : July 21, 1961 Date of issuance : July 21, 1961 Date reissued : 7/5/63; 5/7/64; 1/25/66; 12/6/67; 5/17/78; 5/12/11; 7/14/11 ( Signature) Melvin D. Taylor Manager Atlanta Aircraft Certification Office ( Title) ## Every issue (2) - July 14, 2011: Reissued, Current. [certificate](https://openairdocs.org/files/sha256/d6/00/d600ba19c23872876040b824d5c3b1681c1b32b2ca68a1922baaca0f76183522) - May 12, 2011: Reissued, Historical. [certificate](https://openairdocs.org/files/sha256/b7/99/b7998ed66de1a5d1ea7ff7ef4689951763a6b4c9bd0ea76b8760e3364acb4ace) --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.