AD 74-26-04
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Piper Aircraft Inc. | PA-31 | Airworthiness Directives; Piper Models PA-31 and PA-31-300 Airplanes |
| aircraft | Piper Aircraft Inc. | PA-31-300 | Airworthiness Directives; Piper Models PA-31 and PA-31-300 Airplanes |
Unsafe Condition
Fuel leaking from the heater manual shut-off and solenoid shut-off valves in the nose compartment creates explosion hazards.
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Required Actions
Conduct a pressure check of P/N 492107 manual heater shut-off valve and P/N 756513 solenoid fuel regulator shut-off valve within 25 hours time in service. Replace or repair leaking valves and repeat the pressure check. Remove P/N 492107 and bracket P/N 41948-00 within 125 hours. Install shroud assembly P/N 43493 with associated components over P/N 756513 within 125 hours for serial numbers 31-2 to 31-103.
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Compliance Time
Within 25 hours time in service after the effective date of this AD
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Affected Aircraft
Piper Models PA-31 and PA-31-300, serial numbers 31-2 to 31-7401258 inclusive.
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Federal Register Abstract
Explosion Hazards
Applicability Source Text
Show captured applicability text from the source AD
AD Final Rules - DRS_74-26-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 74-26-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Piper Models PA-31 and PA-31-300 Airplanes Subject: Explosion Hazards Status: Current Citation: This information is not available. Citation Publish Date: 12/12/1974 Effective Date: 12/19/1974 Make: Piper Aircraft Inc. Model: PA-31 | PA-31-300 Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: AIR-700: Compliance & Airworthiness Division Office of Primary Responsibility: AIR-720: Operational Safety Branch CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 74-26-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2044 AD NUMBER: 74-26-04 SUBJECT HEADING: Airworthiness Directives; Piper Models PA-31 and PA-31-300 Airplanes ACTION: SUMMARY: DATES: Effective December 19, 1974. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 74-26-04 PIPER: Amendment 39-2044. Applies to Models PA-31 & PA-31-300 S/N 31- 2 to 31-7401258 inclusive. Compliance required as indicated unless already accomplished: In order to eliminate explosion hazards associated with fuel leaking from the heater manual shut-off and solenoid shut-off valves in the nose compartment, accomplish the following: a. Within 25 hours time in service after the effective date of this AD, conduct a pressure check of the P/N 492107 manual heater shut-off valve and P/N 756513 solenoid fuel regulator shut-off valve. This may be accomplished by operating the right electric fuel pump, turning on the heater manual fuel valve and visually inspecting for fuel seepage around the valve body and connecting line fittings of both shut-off valves. If any leakage is observed, the valve must be replaced or repaired and the pressure check repeated. b. Within 125 hours time in service after the effective date of this AD for Serial Numbers 31-2 to 31-7401258 inclusive, remove manual heater fuel shut-off valve P/N 492107 and bracket P/N 41948-00 in accordance with Piper Service Bulletin No. 417 and subsequent approved revisions. c. Within 125 hours time in service after the effective date of this AD for Serial Numbers 31-2 to 31-103 inclusive, install shroud assembly Piper P/N 43493 with associated cover, overboard drain tube, sealing grommets and clamp over heater solenoid shut-off valve P/N 756513 in accordance with Piper installation drawing No. 41923 and Parts Catalog No. 753703 Fig. 38. d. Alternate equivalent modifications to those described above must be approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. Aircraft may be flown to a base where the maintenance required by this Airworthiness Directive may be performed per FAR's 21.197 and 21.199. (Piper Service Bulletin No. 417 dated August 26, 1974, pertains to this subject.) This amendment is effective December 19, 1974. FOOTER:
Document Text
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AD Final Rules - DRS_74-26-04.html Copy URL Print/Save as PDF Document Versions Feedback Details AD Number: 74-26-04 Document Type: AD Final Rules Docket Number: Unknown Subject Heading: Airworthiness Directives; Piper Models PA-31 and PA-31-300 Airplanes Subject: Explosion Hazards Status: Current Citation: This information is not available. Citation Publish Date: 12/12/1974 Effective Date: 12/19/1974 Make: Piper Aircraft Inc. Model: PA-31 | PA-31-300 Product Type: Aircraft Product Subtype: Small Airplane Affected AD: Superseded AD: Affected By: Superseded By: Service/Office: AIR-700: Compliance & Airworthiness Division Office of Primary Responsibility: AIR-720: Operational Safety Branch CFR Part Reference: Part 39 Comments: AIRWORTHINESS DIRECTIVES FINAL RULES: 74-26-04 CITATION: This information is not available. PAGE NUMBER: DOCKET NUMBER: Unknown AMENDMENT: 39-2044 AD NUMBER: 74-26-04 SUBJECT HEADING: Airworthiness Directives; Piper Models PA-31 and PA-31-300 Airplanes ACTION: SUMMARY: DATES: Effective December 19, 1974. ADDRESSES: FOR FURTHER INFORMATION CONTACT: SUPPLEMENTARY INFORMATION: REGULATORY TEXT: 74-26-04 PIPER: Amendment 39-2044. Applies to Models PA-31 & PA-31-300 S/N 31- 2 to 31-7401258 inclusive. Compliance required as indicated unless already accomplished: In order to eliminate explosion hazards associated with fuel leaking from the heater manual shut-off and solenoid shut-off valves in the nose compartment, accomplish the following: a. Within 25 hours time in service after the effective date of this AD, conduct a pressure check of the P/N 492107 manual heater shut-off valve and P/N 756513 solenoid fuel regulator shut-off valve. This may be accomplished by operating the right electric fuel pump, turning on the heater manual fuel valve and visually inspecting for fuel seepage around the valve body and connecting line fittings of both shut-off valves. If any leakage is observed, the valve must be replaced or repaired and the pressure check repeated. b. Within 125 hours time in service after the effective date of this AD for Serial Numbers 31-2 to 31-7401258 inclusive, remove manual heater fuel shut-off valve P/N 492107 and bracket P/N 41948-00 in accordance with Piper Service Bulletin No. 417 and subsequent approved revisions. c. Within 125 hours time in service after the effective date of this AD for Serial Numbers 31-2 to 31-103 inclusive, install shroud assembly Piper P/N 43493 with associated cover, overboard drain tube, sealing grommets and clamp over heater solenoid shut-off valve P/N 756513 in accordance with Piper installation drawing No. 41923 and Parts Catalog No. 753703 Fig. 38. d. Alternate equivalent modifications to those described above must be approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region. Aircraft may be flown to a base where the maintenance required by this Airworthiness Directive may be performed per FAR's 21.197 and 21.199. (Piper Service Bulletin No. 417 dated August 26, 1974, pertains to this subject.) This amendment is effective December 19, 1974. FOOTER:
Source: Official FAA Source ↗
Retrieved: Apr 8, 2026
Rights: U.S. Government Public Domain
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