AD 78-23-08
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| engine | Lycoming Engines | IO-540-G1B5 | AVCO LYCOMING Model IO-540-G1B5, -K1F5, -P1A5 and -S1A5 Series Engines |
| engine | Lycoming Engines | IO-540-K1F5 | AVCO LYCOMING Model IO-540-G1B5, -K1F5, -P1A5 and -S1A5 Series Engines |
| engine | Lycoming Engines | IO-540-P1A5 | AVCO LYCOMING Model IO-540-G1B5, -K1F5, -P1A5 and -S1A5 Series Engines |
| engine | Lycoming Engines | IO-540-S1A5 | AVCO LYCOMING Model IO-540-G1B5, -K1F5, -P1A5 and -S1A5 Series Engines |
Unsafe Condition
Fuel leakage due to failure of the fuel pump to fuel injector tube elbow.
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Required Actions
Replace the fuel pump to fuel injector tube part number LW-10445 and the fuel pump to fuel injector tube elbow part number LW-10446 with flexible hose assembly part number LW-12877-6-051.
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Compliance Time
within the next 50 hours' in service after the effective date of this AD, unless already accomplished
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Affected Aircraft
AVCO Lycoming Model IO-540-G1B5, -K1F5, -P1A5, and -S1A5 series engines with serial numbers up to and including L-17835-48 or -45A and engines overhauled by Lycoming prior to March 30, 1978.
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Federal Register Abstract
Fuel Pump To Fuel Injector Tube Elbow
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_78-23-08.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 78-23-08 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: AVCO LYCOMING Model IO-540-G1B5, -K1F5, -P1A5 and -S1A5 Series Engines Subject: Fuel Pump To Fuel Injector Tube Elbow Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/07/1978 Make: Lycoming Engines Model: IO-540-G1B5 | IO-540-K1F5 | IO-540-P1A5 | IO-540-S1A5 Product Type: Engine Product Subtype: Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: Office of Primary Responsibility: CFR Part Reference: Part 39 Comments: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 78-23-08 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3334 AD NUMBER: 78-23-08 SUBJECT HEADING: AVCO LYCOMING Model IO-540-G1B5, -K1F5, -P1A5 and -S1A5 Series Engines ACTION: SUMMARY: DATES: Effective November 7, 1978. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 78-23-08 AVCO LYCOMING: Amendment 39-3334. Applies to all IO-540-G1B5, -K1F5, -P1A5 and - S1A5 series engines with serial numbers up to and including L-17835-48 or -45A and all IO-540-G1B5, -K1F5, - P1A5, -S1A5 series engines overhauled (also known as remanufactured) by Lycoming prior to March 30, 1978. Compliance required within the next 50 hours' in service after the effective date of this AD, unless already accomplished. To prevent possible fuel leakage due to failure of the fuel pump to fuel injector tube elbow replace the fuel pump to fuel injector tube part number LW-10445 and the fuel pump to fuel injector tube elbow, part number LW-10446 with flexible hose assembly, part number LW-12877-6-051. Upon submission of substantiating data through an FAA Maintenance Inspector, the Chief, Engineering and Manufacturing Branch, Federal Aviation Administration (FAA), Eastern Region, may adjust the compliance time specified in this AD. (NOTE: AVCO Lycoming Service Bulletin No. 421 covers this subject.) This amendment is effective November 7, 1978. FOOTER:
Document Text
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AD Final Rules - DRS_78-23-08.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 78-23-08 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: AVCO LYCOMING Model IO-540-G1B5, -K1F5, -P1A5 and -S1A5 Series Engines Subject: Fuel Pump To Fuel Injector Tube Elbow Status: Current Citation: This information is not available. Citation Publish Date: Effective Date: 11/07/1978 Make: Lycoming Engines Model: IO-540-G1B5 | IO-540-K1F5 | IO-540-P1A5 | IO-540-S1A5 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: Updated RGL applicability to match AD applicability; CAR C-11-185 AIRWORTHINESS DIRECTIVES FINAL RULES: 78-23-08 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-3334 AD NUMBER: 78-23-08 SUBJECT HEADING: AVCO LYCOMING Model IO-540-G1B5, -K1F5, -P1A5 and -S1A5 Series Engines ACTION: SUMMARY: DATES: Effective November 7, 1978. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 78-23-08 AVCO LYCOMING: Amendment 39-3334. Applies to all IO-540-G1B5, -K1F5, -P1A5 and - S1A5 series engines with serial numbers up to and including L-17835-48 or -45A and all IO-540-G1B5, -K1F5, - P1A5, -S1A5 series engines overhauled (also known as remanufactured) by Lycoming prior to March 30, 1978. Compliance required within the next 50 hours' in service after the effective date of this AD, unless already accomplished. To prevent possible fuel leakage due to failure of the fuel pump to fuel injector tube elbow replace the fuel pump to fuel injector tube part number LW-10445 and the fuel pump to fuel injector tube elbow, part number LW-10446 with flexible hose assembly, part number LW-12877-6-051. Upon submission of substantiating data through an FAA Maintenance Inspector, the Chief, Engineering and Manufacturing Branch, Federal Aviation Administration (FAA), Eastern Region, may adjust the compliance time specified in this AD. (NOTE: AVCO Lycoming Service Bulletin No. 421 covers this subject.) This amendment is effective November 7, 1978. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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