AD 66-20-04
final rule
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Lycoming Engines | IO-320-A1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-320-A2A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-320-B1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-320-B1B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-320-B1C | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-320-B1D | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-320-B2A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-320-C1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-320-E2A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-360-A1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-360-A1B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-360-A2A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-360-A2B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-360-B1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-360-B1B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-360-B1C | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-360-B1D | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-360-B1E | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-360-C1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-360-C1B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-360-D1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-A1A5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-B1A5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-B1B5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-B1C5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-C1B5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-C1C5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-C2C | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-C4B5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-C4C5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-D4A5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-E1A5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-E1B5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-G1A5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-G1B5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-G1C5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-J4A5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-K1A5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | IO-540-K1B5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-A1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-A1B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-A2A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-A2B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-A2C | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-A3A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-A3B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-A3C | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-B1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-B1B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-B2A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-B2B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-B2C | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-B3A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-B3B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-B3C | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-C1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-C1B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-C2A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-C2B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-C2C | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-C3A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-C3B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-C3C | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-D1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-D1B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-D2A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-D2B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-D2C | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-E1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-E1B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-E2A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-E2B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-320-E2C | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-340-A1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-340-A2A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-340-B1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-A1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-A1C | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-A1D | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-A2A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-A2D | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-A2E | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-A3A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-A3D | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-A4A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-B1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-B1B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-B2A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-B2B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-C1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-C1C | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-C2A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-C2B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-C2C | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-C2D | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-D1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-D2A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-360-D2B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-A1A | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-A1A5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-A1B5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-A1C5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-A1D | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-A1D5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-A2B | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-A3D5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-A4A5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-A4B5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-A4C5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-A4D5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-B1A5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-B1B5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-B2A5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-B2B5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-B4A5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-B4B5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-D1A5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-E4A5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-E4B5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-E4C5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-F1A5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-F1B5 | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-J1A5D | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
| engine | Lycoming Engines | O-540-J2A5D | LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines |
Unsafe Condition
Failure of oil filter adapter gasket, part number 74904.
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Required Actions
Replace gasket P/N 74904 with P/N 76691. Inspect studs, cap screws, and tapped holes in the accessory housing mounting pad for proper length or depth per Lycoming Service Bulletin No. 307 or later FAA-approved revision. Replace studs, cap screws, and retap holes as necessary per the bulletin.
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Compliance Time
within the next 50 hours' time in service after the effective date of this AD
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Affected Aircraft
Lycoming Engines models O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines equipped with AC oil filters, excluding specific serial ranges as listed in the AD.
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Federal Register Abstract
Oil Filter Adapter Gasket
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_66-20-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 66-20-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines Subject: Oil Filter Adapter Gasket Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/27/1966 Make: Lycoming Engines Model: IO-320-A1A | IO-320-A2A | IO-320-B1A | IO-320-B1B | IO-320-B1C | IO-320-B1D | IO-320-B2A | IO-320-C1...Show more 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: 66-20-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-277 AD NUMBER: 66-20-04 SUBJECT HEADING: LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines ACTION: SUMMARY: DATES: Effective August 27, 1966. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 66-20-04 LYCOMING: Amdt. 39-277, Part 39, Federal Register August 18, 1966. Applies to Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines Equipped With AC Oil Filters Except O-320- A, -E Series, Engine Serial Number 16128-27 and Higher; O-320-B, -C, and -D Series, Engine Serial Number 6217-39 and Higher; IO-320 Series, Engine Serial Numbers 2110-55A, 2113-55A and Higher; O-360 Series, Engine Serial Number 9346-36A and Higher; O-540 Series, Engine Serial Numbers 9770-40, 9800-40, 9803-40 and Higher; and IO-540 Series, Engine Serial Numbers 2831-48, 2835-48, 2840-48 and Higher. Compliance required within the next 50 hours' time in service after the effective date of this AD, unless already accomplished. To prevent further failures of oil filter adapter gasket, P/N 74904, accomplish the following: (a) Replace gasket, P/N 74904, with gasket, P/N 76691. (b) Inspect the stud, cap screws, and tapped holes in the accessory housing mounting pad for proper length or depth, as applicable, in accordance with Lycoming Service Bulletin No. 307 or later FAA-approved revision. Replace studs and cap screws of improper length and retap holes of insufficient depth as necessary in accordance with Bulletin No. 307 or later FAA-approved revision. This directive effective August 27, 1966. FOOTER:
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AD Final Rules - DRS_66-20-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 66-20-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines Subject: Oil Filter Adapter Gasket Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 08/27/1966 Make: Lycoming Engines Model: IO-320-A1A | IO-320-A2A | IO-320-B1A | IO-320-B1B | IO-320-B1C | IO-320-B1D | IO-320-B2A | IO-320-C1...Show more 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: 66-20-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-277 AD NUMBER: 66-20-04 SUBJECT HEADING: LYCOMING Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines ACTION: SUMMARY: DATES: Effective August 27, 1966. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 66-20-04 LYCOMING: Amdt. 39-277, Part 39, Federal Register August 18, 1966. Applies to Model O-320, IO-320, O-340, O-360, IO-360, O-540, and IO-540 Series Engines Equipped With AC Oil Filters Except O-320- A, -E Series, Engine Serial Number 16128-27 and Higher; O-320-B, -C, and -D Series, Engine Serial Number 6217-39 and Higher; IO-320 Series, Engine Serial Numbers 2110-55A, 2113-55A and Higher; O-360 Series, Engine Serial Number 9346-36A and Higher; O-540 Series, Engine Serial Numbers 9770-40, 9800-40, 9803-40 and Higher; and IO-540 Series, Engine Serial Numbers 2831-48, 2835-48, 2840-48 and Higher. Compliance required within the next 50 hours' time in service after the effective date of this AD, unless already accomplished. To prevent further failures of oil filter adapter gasket, P/N 74904, accomplish the following: (a) Replace gasket, P/N 74904, with gasket, P/N 76691. (b) Inspect the stud, cap screws, and tapped holes in the accessory housing mounting pad for proper length or depth, as applicable, in accordance with Lycoming Service Bulletin No. 307 or later FAA-approved revision. Replace studs and cap screws of improper length and retap holes of insufficient depth as necessary in accordance with Bulletin No. 307 or later FAA-approved revision. This directive effective August 27, 1966. FOOTER:
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