AD 76-13-09
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Continental Motors | TSIO-520-L | TELEDYNE CONTINENTAL MOTORS Model TSIO-520-L Engines |
Unsafe Condition
Cracks in the left hand rear exhaust elbow, P/N 640708, and left and right hand flanges on the exhaust to turbo adapter, P/N 640712, and insufficient end clearance between connector tube assembly, P/N 640711, and connector tube, P/N 640710.
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Required Actions
Inspect for cracks and distortion in the exhaust components per specified steps. Replace cracked or distorted parts with new elbow P/N 642067 and flange P/N 642066 when available. Adjust or replace elbows to ensure gap between flanges is between 0.250 and 0.500 inches. Inspect turbo adapter wall thickness and replace if below 0.075 inches. Reinstall components with specified torque settings.
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Compliance Time
within the next ten hours time in service after the effective date of this AD
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Affected Aircraft
Teledyne Continental Motors Model TSIO-520-L engines with serial numbers 508000 through 508164, and 508166 through 508261.
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Federal Register Abstract
Left Hand Rear Exhaust Elbow, And Left And Right Hand Flanges
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_76-13-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 76-13-09 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: TELEDYNE CONTINENTAL MOTORS Model TSIO-520-L Engines Subject: Left Hand Rear Exhaust Elbow, And Left And Right Hand Flanges Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/26/1976 Make: Continental Motors Model: TSIO-520-L Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 76-13-09 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2691 AD NUMBER: 76-13-09 SUBJECT HEADING: TELEDYNE CONTINENTAL MOTORS Model TSIO-520-L Engines ACTION: SUMMARY: DATES: Effective August 26, 1976. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 76-13-09 TELEDYNE CONTINENTAL MOTORS: Amendment 39-2655 as amended by Amendment 39- 2691. Applies to Teledyne Continental Motors Model TSIO-520-L, serial numbers 508000 through 508164, and serial numbers 508166 through 508261. Compliance required within the next ten hours time in service after the effective date of this AD, unless already accomplished. Inspections covered in steps 1, 2, 3 and 4 below must be repeated each 25 hours time in service from the initial inspection until replaced by a new elbow TCM Part Number 642067 and new exhaust flange TCM Part Number 642066. To detect cracks in the left hand rear exhaust elbow, P/N 640708, and the left and right hand flanges on the exhaust to turbo adapter, P/N 640712, and to provide sufficient end clearance between the connector tube assembly, P/N 640711, and the connector tube, P/N 640710, inspect, repair or replace, as required, in accordance with the following procedure: 1. Remove couplings, P/N 641284, from each side of the adapter. 2. Remove the left hand elbow, (2-4-6 side), P/N 640708, and carefully inspect in the area of the weld closest to the flange, and the flange fillet radius (see illustration for cracks). 3. Check elbow (2-4-6 side), P/N 640708, for distortion in the area shown below (see illustration). 4. If any cracks are evident and/or distortion is readily discernible, replace the elbow (2-4-6), P/N 640708. (Replace with new elbow 642067 and flange 642066 when parts become available.) 5. Slip the connector, P/N 640711, to the right on the elbow (1-3-5 side), P/N 640710, until it bottoms out. With the flanges aligned, the gap between the flange on the turbo adapter (P/N 640712) and the flange on the connector (P/N 640711) must exceed .250 inches but not exceed .500 inches all the way around as shown in illustration. If this gap is less than .250 inches, remove sufficient material from the end of the elbow (1-3-5 side), P/N 640710, to provide .250 to .380 inch gap. If the gap exceeds .500 inches, replace the elbow (1-3-5 side), P/N 640710, with one meeting this inspection requirement. 6. Remove the turbo adapter, P/N 640712, from the engine. Carefully inspect the turbo adapter, P/N 640712, for cracks in the flange fillet radii (see illustration). If cracks are observed, replace. 7. Using suitable micrometers or dial indicator calipers, inspect the turbo adapter, P/N 640712, wall thickness in the machined area adjacent to the flange fillet radius on the entire circumference. The minimum allowable thickness is .075 inches (see illustration). If the wall thickness is less than .075 inches in any local area, replace the turbo adapter, P/N 640712, with one meeting this inspection requirement. 8. Reinstall couplings, P/N 641284. Insure flanges are symmetrically aligned. Tighten couplings to approximately 42 in. lbs. torque. Tap outer periphery of band to distribute tension, then tighten to 50 to 60 in. lbs. of torque. TCM Service Bulletin M76-14 covers this subject. Amendment 39-2655 became effective July 15, 1976. This amendment 39-2691 becomes effective August 26, 1976. FOOTER:
Document Text
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AD Final Rules - DRS_76-13-09.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 76-13-09 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: TELEDYNE CONTINENTAL MOTORS Model TSIO-520-L Engines Subject: Left Hand Rear Exhaust Elbow, And Left And Right Hand Flanges Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/26/1976 Make: Continental Motors Model: TSIO-520-L Product Type: Engine 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: 76-13-09 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2691 AD NUMBER: 76-13-09 SUBJECT HEADING: TELEDYNE CONTINENTAL MOTORS Model TSIO-520-L Engines ACTION: SUMMARY: DATES: Effective August 26, 1976. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 76-13-09 TELEDYNE CONTINENTAL MOTORS: Amendment 39-2655 as amended by Amendment 39- 2691. Applies to Teledyne Continental Motors Model TSIO-520-L, serial numbers 508000 through 508164, and serial numbers 508166 through 508261. Compliance required within the next ten hours time in service after the effective date of this AD, unless already accomplished. Inspections covered in steps 1, 2, 3 and 4 below must be repeated each 25 hours time in service from the initial inspection until replaced by a new elbow TCM Part Number 642067 and new exhaust flange TCM Part Number 642066. To detect cracks in the left hand rear exhaust elbow, P/N 640708, and the left and right hand flanges on the exhaust to turbo adapter, P/N 640712, and to provide sufficient end clearance between the connector tube assembly, P/N 640711, and the connector tube, P/N 640710, inspect, repair or replace, as required, in accordance with the following procedure: 1. Remove couplings, P/N 641284, from each side of the adapter. 2. Remove the left hand elbow, (2-4-6 side), P/N 640708, and carefully inspect in the area of the weld closest to the flange, and the flange fillet radius (see illustration for cracks). 3. Check elbow (2-4-6 side), P/N 640708, for distortion in the area shown below (see illustration). 4. If any cracks are evident and/or distortion is readily discernible, replace the elbow (2-4-6), P/N 640708. (Replace with new elbow 642067 and flange 642066 when parts become available.) 5. Slip the connector, P/N 640711, to the right on the elbow (1-3-5 side), P/N 640710, until it bottoms out. With the flanges aligned, the gap between the flange on the turbo adapter (P/N 640712) and the flange on the connector (P/N 640711) must exceed .250 inches but not exceed .500 inches all the way around as shown in illustration. If this gap is less than .250 inches, remove sufficient material from the end of the elbow (1-3-5 side), P/N 640710, to provide .250 to .380 inch gap. If the gap exceeds .500 inches, replace the elbow (1-3-5 side), P/N 640710, with one meeting this inspection requirement. 6. Remove the turbo adapter, P/N 640712, from the engine. Carefully inspect the turbo adapter, P/N 640712, for cracks in the flange fillet radii (see illustration). If cracks are observed, replace. 7. Using suitable micrometers or dial indicator calipers, inspect the turbo adapter, P/N 640712, wall thickness in the machined area adjacent to the flange fillet radius on the entire circumference. The minimum allowable thickness is .075 inches (see illustration). If the wall thickness is less than .075 inches in any local area, replace the turbo adapter, P/N 640712, with one meeting this inspection requirement. 8. Reinstall couplings, P/N 641284. Insure flanges are symmetrically aligned. Tighten couplings to approximately 42 in. lbs. torque. Tap outer periphery of band to distribute tension, then tighten to 50 to 60 in. lbs. of torque. TCM Service Bulletin M76-14 covers this subject. Amendment 39-2655 became effective July 15, 1976. This amendment 39-2691 becomes effective August 26, 1976. FOOTER:
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