# AD 97-15-01: Pistons

- Type: Airworthiness directive
- Status: Historical
- Products: Teledyne Continental Motors E165-2, E165-3, E165-4, E185-1, E185-10, E185-11, E185-2, E185-3, E185-5, E185-8, E185-9, E225-2 and 52 more
- Superseded by: [AD 97-21-02](https://openairdocs.org/ad/97-21-02)
- Product type: Engine
- Docket: 97-ANE-34-AD
- Registered aircraft: 19,950 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/87EC974C1022F7A386256CC5005F9879.0001
- DRS record last changed: August 7, 2025
- Page: https://openairdocs.org/ad/97-15-01

## The airworthiness directive

97-15-01 Teledyne Continental Motors: Priority Letter issued on July 17, 1997. Docket No. 97-ANE-34-AD.

Applicability: Teledyne Continental Motors (TCM) new and rebuilt Model O-470 and IO-470 series engines with serial numbers (S/Ns) listed in Table 1 of TCM Critical Service Bulletin (CSB) No. CSB97-10, dated June 19, 1997; and TCM Model E-165, E-185, E-225, O-470 and IO-470 series engines, regardless of S/N, which have cylinder(s) with part number and purchase date as shown in Table 2 of TCM CSB No. CSB97-10, dated June 19, 1997. These engines are installed on but not limited to the following aircraft: Bellanca Models 14-19-2 and 14-19-3; Cessna Models 180, 180A through K, 182, 182A through R, 185, 185A through E, 188, 188A, 188B, 210, 210A through C, 210-5 (205), 210-5A (205A), 305A, 305C, 305D, 305F, 310, 310A through Q, E310H, E310J, 310J-1; Frontier-Aerospace, Inc. (Fletcher) Models FU-24 and FU-24A; Luscombe Aircraft Corporation Model 11A; Navion models Navion, NavionA, and Navion D through G; Prop-Jets, Inc. Models 200, 200A through C; Raytheon (formerly Beech) Models 35, A35 through P35, 35R, 35-33, 35-A355, 35-B33, 35-C33, E33, F33, 45 (YT-34), A45 (T-34A, B-45), D45(T-34B), 95-55, 95-55A, 95-B55, 95-B55A and 95-B55B; Reims models F182P and F182Q; and Twin Commander Aircraft, Inc. Model 500-A.

Note 1: This airworthiness directive (AD) applies to each engine identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For engines that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (c) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously.

To prevent extreme side loading of the piston, and consequent failure of the piston and engine, accomplish the following:

  (a) For the TCM O-470 and IO-470 series engines listed by S/N in Table 1 of TCM CSB No. CSB97-10 dated June 19, 1997, within 10 hours time in service (TIS) after receipt of this priority letter AD, accomplish the following:

  (1) Remove from service the cylinders, six each, and the piston pins, six each, in accordance with the Inspection Instructions, Part 2A, and Appendix A of TCM CSB No. CSB97-10, dated June 19, 1997.

  (2) Obtain serviceable replacement parts and reassemble the engine in accordance with the Inspection Instructions, Part 2B, of TCM CSB No. CSB97-10, dated June 19, 1997.

  (b) For the E-165, E-185, E-225, series engines and those O-470 and IO-470 series engines not listed by S/N in Table 1 of TCM CSB No. CSB97-10 dated June 19, 1997, within 10 hours TIS after receipt of this priority letter AD, accomplish the following:

  (1) Determine from engine log books or maintenance records if a cylinder has been replaced with a cylinder purchased in the time frames shown in Table 2 of TCM CSB No. CSB97-10, dated June 19, 1997.

  (2) If a cylinder was not replaced with a cylinder purchased during those time frames listed in the CSB, or if a cylinder is identified with the letter "M" or "P" steel stamped after the cylinder position number, as cylinders marked with "M" or "P" have a surface finish that has been found to be within specification, no further action is required. The cylinder position number is located at the 12 o'clock position on the cylinder mounting flange.

  (3) If a cylinder has been replaced with a cylinder purchased during those time frames listed in the CSB, remove from service the affected cylinders and piston pins in accordancewith the Inspection Instructions, Part 2A, and Appendix A of TCM CSB No. CSB97-10, dated June 19, 1997.

  (4) Obtain serviceable replacement parts and reassemble the engine in accordance with the Inspection Instructions, Part 2B, of TCM CSB No. CSB97-10, dated June 19, 1997.

  (c) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Atlanta Aircraft Certification Office. Operators shall submit their requests through an appropriate FAA Maintenance Inspector, who may add comments and then send it to the Manager, Atlanta Aircraft Certification Office.

Note 2: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the Atlanta Aircraft Certification Office.

  (d) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14CFR 21.197 and 21.199) to operate the aircraft to a location where the requirements of this AD can be accomplished.

  (e) Copies of the applicable service information may be obtained from Teledyne Continental Motors, P.O. Box 90, Mobile, AL 36601; telephone (334) 438-3411. This information may be examined at the FAA, New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Burlington, MA.

  (f) Priority Letter AD 97-15-01, issued July 17, 1997, becomes effective upon receipt.

## Rule preamble

### Supplementary information

97-15-01 Teledyne Continental Motors

This priority letter Airworthiness Directive (AD) is prompted by a report from Teledyne Continental Motors (TCM) of an engine equipped with factory new cylinders with approximately 28 hours time in service (TIS) that was discovered to have high aluminum particulates during an oil analysis. Further investigation revealed the piston pin plug was experiencing increased wear, which was, in turn, traced to the roughness of the cylinder bore. A stock sweep at the factory revealed 10 additional cylinders with this condition. The cylinder bore surface finish on some cylinders is rougher than specified. This condition was caused during a manganese phosphate coating process on the cylinder barrel bore. The cylinders are exposed to the phosphate process in batches of 10 cylinders. The manganese phosphate coating provides resistance to corrosion during the first hours of operation. The problem occurred because of extended exposure of the cylinder bore to the manganese phosphate treatment which results in the surface finish being rougher than specified, although the piston pin plug will wear first; it will, in turn, wear a groove in the cylinder wall which will cause massive oil consumption in the near future. This will result in accelerated piston pin plug wear, as the piston pin plug is made of aluminum while the cylinder barrel is made of nitrided steel. The FAA has determined that one side of the piston pin could disconnect from the piston if the wear of the pin plug becomes excessive. This condition, if not corrected, can result in extreme side loading of the piston, and consequent failure of the piston and engine.

The FAA has reviewed and approved the technical contents of TCM Critical Service Bulletin (CSB) No. CSB97-10, dated June 19, 1997, that provides a list of serial numbers (S/Ns) of new and rebuilt model O-470 and IO-470 engines with affected cylinders installed, and a list of cylinders with part number and purchase date that may be installed on E-165, E-185, E-225, O-470 and IO-470 series engines, regardless of serial number. This CSB describes procedures for removal and shipment to the factory of affected cylinders, and procedures for reassembly with serviceable parts.

Since an unsafe condition has been identified that is likely to exist or develop on other engines of this same type design, this AD requires, within 10 hours TIS after receipt of this priority letter AD, for new and rebuilt TCM O-470 and IO-470 series engines listed by S/N in the CSB, removal from service of affected cylinders, and reassembly with serviceable parts. For all other engines listed in the applicability paragraph, this AD requires determining from engine log books or maintenance records if a possibly defective cylinder has been purchased and installed in the time frames shown in the CSB, and, if so, removal from service, and reassembly of the engine with serviceable parts. Cylinders marked with "M" or "P"have a surface finish that has been found to be within specification, and therefore are not affected by this AD. The actions are required to be accomplished in accordance with the CSB described previously.

This rule is issued under 49 U.S.C. Section 44701 (formerly section 601 of the Federal Aviation Act of 1958) pursuant to the authority delegated to me by the Administrator, and is effective immediately upon receipt of this priority letter.

## Affected data sheets (6) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS E-273](https://openairdocs.org/tcds/E-273): Continental Aerospace Technologies, Inc.; names 21 of 21 models: O-470-G-CI, O-470-T, O-470-B-CI, O-470-N, O-470-R, IO-470-C, O-470-H, O-470-A…
- [TCDS 3E1](https://openairdocs.org/tcds/3E1): Continental Aerospace Technologies, Inc.; names 18 of 19 models: IO-470-H, IO-470-D, IO-470-R, IO-470-J, IO-470-LO, IO-470-M, IO-470-L, IO-470-P…
- [TCDS E-246](https://openairdocs.org/tcds/E-246): Continental Aerospace Technologies, Inc.; names 11 of 11 models: E185-3, E185-1, E185-2, E165-2, E165-3, E185-11, E185-9, E185-10…
- [TCDS E-269](https://openairdocs.org/tcds/E-269): Continental Aerospace Technologies, Inc.; names 8 of 8 models: O-470-11, O-470-15, O-470-11B-CI, O-470-13, O-470-11-CI, O-470-11B, O-470-4, O-470-13A
- [TCDS E-267](https://openairdocs.org/tcds/E-267): Continental Aerospace Technologies, Inc.; names 4 of 4 models: E225-8, E225-9, E225-4, E225-2
- [TCDS E-281](https://openairdocs.org/tcds/E-281): Continental Aerospace Technologies, Inc.; names 1 of 2 models: O-470-2

## Registered aircraft it may apply to (OpenAirDocs)

Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment.

- Aircraft: 19,950 (0 by airframe model, 19,950 by engine model)
- Makers: Cessna 14,089, Beech 4,805, Ryan 277, North American 235, Navion 161, Bellanca 106, Downer 41, Luscombe 23, Aero Commander 16, Stinson 16

Models with the most aircraft:

- [Continental O-470 series](https://openairdocs.org/engine/continental-o-470-series): 12,779 aircraft (engine model)
- [Continental I0-470 series](https://openairdocs.org/engine/continental-i0-470-series): 4,499 aircraft (engine model)
- [Continental E185 series](https://openairdocs.org/engine/continental-e185-series): 1,108 aircraft (engine model)
- [Continental E225 series](https://openairdocs.org/engine/continental-e225-series): 979 aircraft (engine model)
- [Continental IO-470 series](https://openairdocs.org/engine/continental-io-470-series): 225 aircraft (engine model)
- [Continental O-470R](https://openairdocs.org/engine/continental-o-470r): 107 aircraft (engine model)
- [Continental O-470-U](https://openairdocs.org/engine/continental-o-470-u): 56 aircraft (engine model)
- [Continental IO-470-L](https://openairdocs.org/engine/continental-io-470-l): 22 aircraft (engine model)
- [Continental O-470-S](https://openairdocs.org/engine/continental-o-470-s): 22 aircraft (engine model)
- [Continental O-470-L](https://openairdocs.org/engine/continental-o-470-l): 19 aircraft (engine model)
- [Continental O-470-K](https://openairdocs.org/engine/continental-o-470-k): 13 aircraft (engine model)
- [Continental IO-470-N](https://openairdocs.org/engine/continental-io-470-n): 12 aircraft (engine model)
- [Continental IO-470-F](https://openairdocs.org/engine/continental-io-470-f): 9 aircraft (engine model)
- [Continental E165 series](https://openairdocs.org/engine/continental-e165-series): 8 aircraft (engine model)
- [Continental IO-470-VO](https://openairdocs.org/engine/continental-io-470-vo): 8 aircraft (engine model)
- [Continental E225-4](https://openairdocs.org/engine/continental-e225-4): 7 aircraft (engine model)
- [Continental E225-8](https://openairdocs.org/engine/continental-e225-8): 7 aircraft (engine model)
- [Continental IO-470-D](https://openairdocs.org/engine/continental-io-470-d): 7 aircraft (engine model)
- [Continental IO-470-S](https://openairdocs.org/engine/continental-io-470-s): 7 aircraft (engine model)
- [Continental O-470-J](https://openairdocs.org/engine/continental-o-470-j): 6 aircraft (engine model)

All 40 models: https://openairdocs.org/ad/97-15-01/models.md
Every aircraft: https://openairdocs.org/ad/97-15-01/aircraft.md

## Related documents

- [AD 97-21-02](https://openairdocs.org/ad/97-21-02): Cylinders · Continental Motors E165-2, E165-3, E165-4 and 61 more. Effective Oct 27, 1997. Supersedes this AD

Its text cites no advisory circulars or STCs.

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