# AD 81-12-06 R1: Magnetos - Type: Airworthiness directive - Status: Current - Products: Bendix Magnetos, LTIO-540-J2BD and TIO-540-J2BD - Effective: November 12, 1981 - Superseded by: Nothing supersedes this AD - Product type: Appliance - Amendment: 39-4249 - Registered aircraft: 5,106 may be affected, by airframe or engine model (OpenAirDocs) - FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/1C46A9DCA3A4F6BE86256A340061A2D7.0001 - DRS record last changed: May 30, 2024 - Page: https://openairdocs.org/ad/81-12-06-R1 ## The airworthiness directive 81-12-06 R1 BENDIX: Amendment 39-4249. Applies to Bendix Engine Products Division D-3000 and D-3200 (Blue) series magnetos identified as follows, unless previously identified by the letter "X", on the upper left area of magneto data plate: a. D-3000 series (see models specified under "MAGNETO IDENTIFICATION") pressurized (dark blue) magnetos with serial numbers below 1423, installed on AVCO Lycoming TIO, LTIO-540-J2BD engines. MAGNETO IDENTIFICATION MODEL PART NO. D6LN-3200 10-682910-13 D6RN-3200 10-682910-18 These magnetos are installed on but not limited to the following aircraft engines or aircraft engine/aircraft combinations: AVCO LYCOMING ENGINES AIRCRAFT INSTALLATIONS TIO-540-J2BD Piper PA-31-350; LTIO-540-J2BD STC SA1151SO and SA970SO Colemill conversion of Piper PA-31, PA-31-325 and PA-31-350; STC SA980NW Machen Industries conversion of Piper Aerostar 600 STC SA762NW Machen Industries conversion of Beechcraft Bonanza B35 and A36 series.To detect loose distributor gear rotating electrodes on magnetos having 100 hours or more in service since new or overhaul, accomplish paragraph c, before further flight, unless previously accomplished, and every 50 hours in service thereafter until the gears are replaced with laser welded gear assemblies identified by the presence of the letter "Z" or the letters "XO" on the retaining ring end of the gear axle. b. All D-3000 and D-3200 series (blue) magnetos with serial numbers 100 through 1968 not covered by paragraph a, unless previously accomplished. To detect loose distributor gear rotating electrodes on magnetos having 100 hours or more in service since new or overhaul, accomplish paragraph c, before the expiration of 50 hours in service since new or overhaul after the effective date of this AD unless previously accomplished and every 50 hours in service thereafter until the gears are replaced with laser welded gear assemblies identified by the presence of the letter"Z" or the letters "XO" on the retaining ring end of the gear axle or the letter "L", stamped on the distributor gear electrode. c. 1. Remove the distributor block from the magneto and the gears from the block. 2. (A). Inspect distributor gears and block for the presence of bronze colored particles and for indications of metal to metal contact of electrodes. (B). Inspect rotating electrode for looseness by holding the gear in one hand while attempting to move the distributor gear electrode relative to the axle, clock-wise and vertically. Any looseness of the rotating electrode is reason for rejection of distributor gear. 3. If the distributor block is contaminated with brass filings or bronze colored dust, inspect the engine as follows: (A). Observe engine pistons through spark plug hole for evidence of burning. (B). Check valve dry tappet clearance per engine manufacturer's instructions. If piston damage or lower than specified dry tappet clearance is present, the engine must be inspected, in accordance with the engine manufacturer's instructions, for continued airworthiness. 4. Reinstall serviceable distributor gears into a clean serviceable distributor block. Reassemble the magneto and check timing as appropriate. 5. (A). Make an engine log entry of compliance, including magneto serial number. (B). When the laser beam welded distributor gear has been installed in a D-3000 or D-3200 series magneto, identify that magneto by metal stamping the letter "X", on the upper left area of magneto data plate and make the appropriate log entry. Equivalent inspections and procedures must be approved by the Chief of the Engineering and Manufacturing Branch, AEA-210, Federal Aviation Administration (FAA) Eastern Region. As permitted by FAR 21.197, aircraft may be flown to a base where maintenance required by this AD can be accomplished. (Bendix Service Bulletins 618 and 619 pertain to paragraphs a and b respectively.) This Airworthiness Directive is effective November 12, 1981, and paragraph a. was effective upon receipt for all recipients of airmail letter dated June 5, 1981, which covered that subject. ## Affected data sheets (1) (OpenAirDocs) The type certificate data sheets whose models the AD names. - [TCDS E14EA](https://openairdocs.org/tcds/E14EA): Lycoming Engines; names 2 of 40 models: TIO-540-J2BD, LTIO-540-J2BD ## 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: 5,106 (0 by airframe model, 5,106 by engine model) - Makers: Piper 3,676, Cessna 632, Mooney 222, Aero Commander 117, Bellanca 111, Smith 98, Rockwell International 93, Socata 51, Commander 21, Aerofab 17 Models with the most aircraft: - [Lycoming TI0-540 series](https://openairdocs.org/engine/lycoming-ti0-540-series): 4,886 aircraft (engine model) - [Lycoming TIO-540 series](https://openairdocs.org/engine/lycoming-tio-540-series): 191 aircraft (engine model) - [Lycoming TIO-540-J2BD](https://openairdocs.org/engine/lycoming-tio-540-j2bd): 24 aircraft (engine model) - [Lycoming LTIO-540-J2BD](https://openairdocs.org/engine/lycoming-ltio-540-j2bd): 5 aircraft (engine model) All 5 models: https://openairdocs.org/ad/81-12-06-R1/models.md Every aircraft: https://openairdocs.org/ad/81-12-06-R1/aircraft.md ## Related documents - [STC SA1151SO](https://openairdocs.org/stc/SA1151SO): Installation of Hartzell four-blade Propellers, cowling changes, winglets or wingtip extension, optional governor arm adaptor, and optional engine isolator mounts. Mike Jones Aircraft Sales Inc., Cited in the text - [STC SA762NW](https://openairdocs.org/stc/SA762NW): Installation of a Lycoming TIO-540-J2BD (MB) engine, Hartzell HC-F3YR-1RF/F8468AB-8Q propeller and associated systems.. Machen Inc, Cited in the text - [STC SA970SO](https://openairdocs.org/stc/SA970SO): Installation of Lycoming TIO-540-J2BD or TIO-540-J2B engines and Hartzell propellers HC-C4YR-2/FC7663D-4R or HC-C4YR-2/FC7663D-6Q, additional fuel pump and related cowling changes.Modification Drawing Piper Navajo PA-31 Navajo-Panther-Drawing 68000, Revision D, Dated 5/17/82. Installation Instructions for Modification of Piper Navajo Model PA-31 and PA-31-325, Drawing 68000, change D dated 5/17/82 and Supplemental Type Certificate (STC) SA970SO. Installation Procedures Boost Pump PA-31 Drawing 62000 A Change dated November 30, 1977. (PA-31 Only) Piper Kit 760-905 Colemill Enterprises, Inc., Process Specification for Drawings 64000 and 66000, dated August 31, 1977. Colemill Enterprises, Inc., Process Specification #500 for Piper Wing Caps and Winglets, dated September 1, 1981. Later FAA approved revisions of the above data are acceptable.. Mike Jones Aircraft Sales Inc., Cited in the text - [STC SA980NW](https://openairdocs.org/stc/SA980NW): Installation of Lycoming engines, Hartzell propellers, aerodynamic performance package and associated systems. (See STC for model numbers).. Machen Inc, Cited in the text --- 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.