Airworthiness Directive · Amendment 39-14297 · Teledyne Continental Motors GTSIO-520 Series Reciprocating Engines
Teledyne Continental Motors GTSIO-520 Series Reciprocating Engines
Superseded. A later AD replaced this one: AD 2007-05-15. Comply with the one in force.
This AD applies to Teledyne Continental Motors (TCM) GTSIO-520 series reciprocating engines. These engines are installed on, but not limited to, Twin Commander (formerly Aero Commander) model 685, Cessna model 404, 411 series, and 421 series, British Aerospace, Aircraft Group, Scottish Division model B.206 series 2 and Aeronautica Macchi, model AM-3 airplanes.
The FAA is adopting a new airworthiness directive (AD) for Teledyne Continental Motors (TCM) GTSIO-520 series reciprocating engines. This AD requires initial and repetitive visual inspections of the starter adapter assembly and crankshaft gear. This AD also requires unscheduled visual inspections of the starter adapter assembly and crankshaft gear due to a rough-running engine. This AD also requires replacement of the starter adapter shaft gear needle bearing with a certain bushing. Also, this AD requires installation of a certain TCM service kit at the next engine overhaul, or at the next starter adapter replacement, whichever occurs first. This AD results from six service difficulty reports and one fatal accident report received related to failed starter adapter assemblies. We are issuing this AD to prevent failure of the starter adapter assembly and or crankshaft gear, resulting in failure of the engine and possible forced landing.
You are responsible for having the actions required by this AD performed within the compliance times specified unless the actions have already been done.
If, during an inspection required by paragraph (g), (h), (i), or (j) of this AD, you find needle bearing, part number (P/N) 537721, installed in the crankcase, replace it with bushing, P/N 654472, before reassembling components. Use the bushing installation procedure specified in Part 4 of TCM Mandatory Service Bulletin (MSB) No. MSB94-4F, dated July 5, 2005.
For any engine that experiences rough running conditions regardless of time-in-service (TIS), do the following:
(1) Before further flight, perform the inspection procedures specified in Part 1 and Part 3 of TCM MSB No. MSB94-4F, dated July 5, 2005, and replace components as necessary.
(2) An engine is considered rough-running if there is a sudden increase in the perceived vibration levels that cannot be cleared by adjustment of the engine controls; particularly the fuel mixture setting. Information on a rough running engines can be found in the aircraft manufacturer's Airplane Flight Manual, Pilot's Operating Handbook, or Aircraft Owners Manual.
For any engine, at the next 100-hour or annual inspection, whichever occurs first, do the following:
(1) Perform the inspection procedures specified in Part 2 of TCM MSB No. MSB94-4F, dated July 5, 2005, and replace components as necessary.
(2) Thereafter, at each 100-hour inspection, (plus or minus 10 hours), and annual inspection, perform repetitive inspections and component replacements as specified in paragraph (h)(1) of this AD.
(i) For any starter adapter with 400 hours or more TIS or unknown TIS on the effective date of this AD, do the following:
(1) Within 25 hours TIS, perform the inspection procedures specified in Part 3 of TCM MSB No. MSB94-4F, dated July 5, 2005, and replace components as necessary.
(2) Thereafter, at 400-hour TIS intervals, (plus or minus 10 hours), perform repetitive inspections and component replacements specified in Part 3 of TCM MSB No. MSB94-4F, dated July 5, 2005, and replace components as necessary.
For any starter adapter with fewer than 400 hours TIS on the effective date of this AD, do the following:
(1) Upon accumulation of 400 hours TIS, (plus or minus 10 hours), perform the inspection procedures specified in Part 3 of TCM MSB No. MSB94-4F, dated July 5, 2005, and replace components as necessary.
(2) Thereafter, at 400-hour TIS intervals, (plus or minus 10 hours), perform repetitive inspections and component replacements, as specified in Part 3 of TCM MSB No. MSB94-4F, dated July 5, 2005, and replace components as necessary.
At the next engine overhaul or starter adapter replacement after the effective date of this AD, whichever occurs first, do the following:
(1) Install TCM service kit, P/N EQ6642R. Use the service kit installation procedures specified in Part 5 of TCM MSB No. MSB94-4F, dated July 5, 2005.
(2) Continue performing the inspections and component replacements specified in paragraphs (g), (h), and (i) of this AD.
Special flight permits are prohibited for rough-running engines described in paragraph (g)(2) of this AD.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
