AD 79-12-07

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AD Number:
79-12-07
Document Type:
AD Final Rules
Docket Number:
Unknown
Subject Heading:
Airworthiness Directives; BENDIX: Applies to Bendix Model D-2000/D-2200 Series (Green Distributor ...Show more
Subject:
Magnetos
Status:
Current
Citation:
This information is not available.
Citation Publish Date:
Effective Date:
06/19/1979
Make:
Bendix | Lycoming Engines | Textron Lycoming, AVCO Corporation
Model:
Magnetos | TIO-540-F2BD | TIO-540-N2BD | TIO-540-R2AD | IO-720-B1BD | IO-720-D1CD
Product Type:
Appliance
Product Subtype:
Affected AD:
Superseded AD:
Affected By:
Superseded By:
Service/Office:
Office of Primary Responsibility:
CFR Part Reference:
Part 39
Comments:
AIRWORTHINESS DIRECTIVES FINAL RULES: 79-12-07
CITATION:   This information is not available.

PAGE NUMBER:  

DOCKET NUMBER:   Unknown

AMENDMENT:   39-3495

AD NUMBER:   79-12-07

SUBJECT HEADING:   Airworthiness Directives; BENDIX: Applies to Bendix Model D-2000/D-2200 Series (Green Distributor Block Only) Six-and-Eight-Cylinder Magnetos

ACTION:  

SUMMARY:  

DATES:   Effective June 19, 1979.

ADDRESSES:  

FOR FURTHER INFORMATION CONTACT:  

SUPPLEMENTARY INFORMATION:  

REGULATORY TEXT:  
79-12-07 BENDIX: Amendment 39-3495. Applies to Bendix Model D-2000/D-2200 series (green distributor block only) six-and-eight-cylinder magnetos identified as follows:

Magneto

Model	
Part No.

D6LN-2031	
10-382560-53

D8LN-2200	
10-382620-51

D6LN-2230	
10-382910-53

D8LN-2200	
10-382920-51

D6RN-2230	
10-382910-58

D6RN-2230	
10-382910-12

D6LN-2230	
10-382910-17

D6LN-2230	
10-382610-53

These magnetos are installed on but not limited to the following aircraft engines or aircraft engine/aircraft combinations:

AVCO Lycoming Engines	Installations
TIO-540-R2AD	
TIO-540-F2BD	
TIO-540-N2BD	
IO-720-B1BD	
IO-720-D1CD	
IO-720-D1CD	Piper, PA-36-375
IO-720-D1CD	Cessna 414
IO-720-B1BD	per Riley STC SA2680-SW
IO-720-B1BD	Rockwell 500S, 560S, and 680S modified by STC SA2691WE
IO-720-B1BD	Rockwell 680F, 680FL and 680FLP modified by STC SA2891WE

To detect loose distributor block bushings, accomplish the following within the next 10 hours in service after the effective date of this A.D. unless previously accomplished, and every 25 hours thereafter until green distributor blocks are replaced by comparable black distributor blocks with part numbers as follows:

P/N 10-382978 by 10-382998 and

P/N 10-382976 by 10-382972, or equivalent FAA approved parts and procedures.

a. Remove the ventilator plugs, threaded bushing, or solid plug from both ends of the magneto housing, as applicable.

b. Remove gear axle retaining ring P/N 10-92815-37, plain washer P/N 10-50753, and felt washer P/N 10-50752 from both distributor gear axle positions.

c. Fabricate a 1/4 in. round probe of non-metallic material, preferably wood dowel rod, approximately six inches long, with one end approximately 1/8 in. wide by 1/8 in. thick by 1 in. long to resemble a screw driver blade.

d. Insert the formed end of the tool thru the inspection hole at one end of the magneto housing and between two teeth of the distributor gear. Gently so as not to damage the gear teeth, attempt to push the gear back and forth sideways, while observing the corresponding bronze bushing in the distributor block. If there is no movement between the bushing and the block, insert the tool under the flat surface of the gear on its outside diameter. Exert pressure on the end of the tool to lift the gear towards the distributor block. Inspect for movement between the bushing and the block. If no bushing movement is detected by either of these two inspections, repeat the procedures at the gear bushing location at the opposite end of the magneto.

e. If no movement is detected, reassemble the magneto per maintenance and overhaul instructions listed in Bendix publications L-928-1 and L-945 or other approved procedures.

f. If bushing movement is detected at either end, the distributor block must be replaced prior to further flight. When replacing distributor block, center the block relative to any lateral movement of block.

g. Tighten distributor block screws to a torque value of 25 to 30 inch lbs. Reassemble the magneto according to applicable instructions in D-2000/D-2200 series magneto overhaul publication, Bendix Form L-945 and tighten the magneto cover screws to a torque value of 30-35 in. lb for black magnetos and 40-45 in. lb for gray magnetos.

h. If replacing the green distributor block with a black distributor block, reidentify the magneto system P/N and magneto P/N by stamping the numeral 1 over the first digit of the dash number suffixes. For example:

System P/N -201 becomes -101

Magneto P/N -51 becomes -11

Record magneto serial number in aircraft engine log. Equivalent methods of compliance must be approved by
the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. As permitted by FAR 21.197, aircraft may be flown to a base where maintenance required by this airworthiness directive can be accomplished.

Bendix Service Bulletin No. 606 pertains to this problem.

This amendment is effective June 19, 1979, except for those persons to whom it was made effective by emergency airmail letter dated April 19, 1979.

FOOTER: