# Diamond Aircraft Mandatory Service Bulletin F4-037: Revision 3 - Rights: © Diamond Aircraft. Filed by the FAA in regulations.gov docket FAA-2025-5397; AD 2026-06-03 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. - Document: [Diamond Aircraft Mandatory Service Bulletin F4-037](https://openairdocs.org/service-documents/diamond/f4-037.md) - Title as filed: Diamond Aircraft Industries Work Instruction WI-MSB F4-037 Rev 0 - Pages: 4 - PDF: https://openairdocs.org/files/sha256/08/09/08096d7c9eddfb15ce6a2016ff596a87645adbe29ee73afe500d955bdda9fded - Page: https://openairdocs.org/service-documents/diamond/f4-037/file/08096d7c9edd ## Text This text is OCR from a scan. OCR can misread letters and numbers. Each page's text from the PDF; open the PDF at a page with #page=N. ### Page 1 (OCR) Diamond Aircraft Industries WORK INSTRUCTION win Diamond AIRCRAFT Model DA 40 F WORK INSTRUCTION WI-MSB F4-037 REV. 0 GENERAL INFORMATION I.1 Subject Replacement of fuel tank connection hoses (flexible couplings). 1.2 Reference Documents DA 40 series Airplane Maintenance Manual, Doc. No. 6.02.01, latest effective issue. 1.3 Remarks 1. All work must be done by a certified aircraft service station or a certified aircraft maintenance mechanic. 2. All work, in particular if not described in this work instruction, must be done in accordance with the referenced maintenance manual. 3. For conversion factors between SI units and US/Imperial units, refer to AMM Chapter 02. 4. In case of doubt, contact Diamond Aircraft Industries Inc. DRAWINGS, SPECIAL TOOLS & MATERIALS II.1 Drawings None. 11.2 Special Tools None. II.3 Material Qty Part Number Description 2 D41-2817-10-70 Fuel tank connection hose (flexible coupling) for DA 40 F standard tank 4 D41-2817-10-70 Fuel tank connection hose (flexible coupling) for DA 40 F long range tank (OÄM 40-071) WI-MSB F4-037 Rev. 0 © DAI 2019 ALL RIGHTS RESERVED, PROPRIETARY DOCUMENT Internet: www.diamondair.com Page 1 of 4 Email: Techpubs@diamondair.com 01 July 2019 ### Page 2 (OCR) Diamond Aircraft Industries Diamond WORK INSTRUCTION AIRCRAFT Model DA 40 F INSTRUCTIONS NOTE: the following images show the difference between the two types of fuel tank connection hoses (flexible couplings) in the field. BENOLPRESS, this fuel tank connection hose has a light blue layer in the cross-section. Only a fraction of these hoses come from the affected two batches. BENOLPRESS D41-2817-10-70, this fuel tank connection hose has an all black cross section and is not affected D41-2817-10-70 not affected WI-MSB F4-037 Rev. 0 © DAI 2019 ALL RIGHTS RESERVED, PROPRIETARY DOCUMENT Internet: www.diamondair.com Page 2 of 4 Email: Techpubs@diamondair.com 01 July 2019 ### Page 3 (OCR) Diamond Aircraft Industries Diamond WORK INSTRUCTION AIRCRAFT* Model DA 40 F ..1 Replacement of Main Fuel Tank Connection Hoses 1. Remove the main fuel tank assembly from the aircraft in accordance with AMM Chapter 28-10. 2. Disassemble the main fuel tank assembly in accordance with AMM Chapter 28-10. 3. Examine the fuel tank connection hoses for damage, deterioration, and detached rubber parts. 4. If the fuel tank connection hoses are found to be damaged, inspect the fuel tank chambers, and remove detached rubber material in accordance with Section III.2 of this service bulletin. 5. Assemble the main fuel tank assembly with the new fuel tank connection hoses (P/N D41-2817- 10-70) in accordance with AMM Chapter 28-10. 6. Install the main fuel tank assembly in to the aircraft in accordance with AMM Chapter 28-10. 7. Do steps 1 to 6 on the opposite side of the aircraft. 8. Clean working areas, and check for foreign objects. 9. Check all altered, replaced, repaired parts for proper function. 10. Test all systems in working area for proper function. 11. Make all necessary entries in the airplane logs. 12. Fill in the execution report, and send it to Techpubs@diamondair.com. II.2 Inspection of Main Fuel Tank Chambers and Removal of Detached Rubber Parts 1. Examine all fuel tank chambers for detached rubber material. Remove any detached rubber material from the fuel tank chambers. CAUTION: pay increased attention to areas with limited access of the inner chamber of the main fuel tank, especially the area in the fuel trap and the area underneath the fuel trap (sediment trap & drain). NOTE: to improve access and inspectability of these areas, the fuel low level switch, the fuel finger filter, and the fuel drain valve can be removed. NOTE: optionally, use a borescope to inspect areas with limited access. 2. If removed during examination of the fuel tank chambers for detached rubber particles: A. Install the fuel low level switch. B. Install the fuel finger filter. C. Install the fuel drain valve. 3. Remove, clean, and re-install the fuel gascolator filter in accordance with AMM Chapter 28-20. WI-MSB F4-037 Rev. 0 © DAI 2019 ALL RIGHTS RESERVED, PROPRIETARY DOCUMENT Internet: www.diamondair.com Page 3 of 4 Email: Techpubs@diamondair.com 01 July 2019 ### Page 4 (OCR) Diamond Aircraft Industries « Diamond WORK INSTRUCTION AIRCRAFT Model DA 40 F 4. Remove, and clean the fuel servo inlet screen with methyl-ethyl-keytone or acetone, then re- install. 5. Flush all fuel lines connecting the main fuel tanks to the gascolator with clean fuel. WI-MSB F4-037 Rev. 0 © DAI 2019 ALL RIGHTS RESERVED, PROPRIETARY DOCUMENT Internet: www.diamondair.com Page 4 of 4 Email: Techpubs@diamondair.com 01 July 2019 --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain, except the copies of manufacturers’ service documents, which belong to their rights holders.