 | GEnx-1B SERVICE BULLETIN - 73-0057 R03 | Revised: 05/23/2019 |
| SB 73-0057 R03 ENGINE FUEL AND CONTROL - Fuel Injection Nozzles (73-11-30) - Fuel Nozzle Machine Bolt Replacement | Issued: 07/13/2017 | |
| GEnx-1B SERVICE BULLETIN - 73-0057 R03 | Revised: 05/23/2019 |
| SB 73-0057 R03 ENGINE FUEL AND CONTROL - Fuel Injection Nozzles (73-11-30) - Fuel Nozzle Machine Bolt Replacement | Issued: 07/13/2017 | |
| GE Designated: -CONFIDENTIAL- | |
| The information contained in this document is GE proprietary information and is disclosed in confidence. It is the property of GE and shall not be used, disclosed to others or reproduced without the express written consent of GE, including, but without limitation, it is not to be used in the creation, manufacture, development, or derivation of any repairs, modifications, spare parts, designs, or configuration changes or to obtain FAA or any other government or regulatory approval to do so. If consent is given for reproduction in whole or in part, this notice and the notice set forth on each page of this document shall appear in any such reproduction in whole or part. | |
| This technical data is considered subject to the Export Administration Regulations (EAR) pursuant to 15 CFR Parts 730-774. Transfer of this data by any means to a Non-U.S. Person, whether in the United States or abroad, without the proper U.S. Government authorization (e.g., License, exemption, NLR, etc.), is strictly prohibited. | |
| Copyright (2019) General Electric Company, U.S.A. |
| TRANSMITTAL INFORMATION |
| REVISION 3 TO SERVICE BULLETIN 73-0057 |
| Revision 3 is issued to update paragraphs 1., PLANNING INFORMATION, 2., MATERIAL INFORMATION, and 3., ACCOMPLISHMENT INSTRUCTIONS. |
| Revision 2 was issued May 31, 2018. Revision 1 was issued September 14, 2017. The original was issued July 13, 2017. Revision bars in the left margin identify changes. |
| 1. | PLANNING INFORMATION |
| A. | Effectivity |
| * * * FOR GEnx-1B64, -1B64/P1, -1B64/P2, -1B67, -1B67/P1, -1B67/P2, -1B70, -1B70/75/P1, -1B70/75/P2, -1B70/P1, -1B70/P2, -1B70C/P1, -1B70C/P2, -1B74/75/P1, -1B74/75/P2, -1B76/P2, -1B76A/P2 |
| This Service Bulletin is applicable to these GEnx-1B engines: |
| GEnx-1B engines, serial numbers 956-101 through 956-943. |
| These serial numbers are the best available data. |
| The machine bolts P/N AS3237-14 are affected by this Service Bulletin. |
| B. | Description |
| This Service Bulletin provides instructions to replace all 88 machine bolts P/N AS3237-14 with longer machine bolts P/N J1494P15A or P/N AS3237-16 to prevent future occurrences of loose or missing machine bolts, and any subsequent damage that can result to the under-cowl hardware. |
| C. | Compliance |
| Category 3 |
| GE recommends that you do this Service Bulletin at the next shop visit of the engine/module. |
| Impact C |
| This recommendation is to address a condition that may result in a Non-Event operational disruption, Unscheduled Engine Removals (UER), Out-Station-Removals or Aircraft on the Ground (AOG). |
| NOTE: |
|
| This Service Bulletin is offered to improve the reliability or performance of your GE product, or to help prevent the occurrence of the event or condition described in this Service Bulletin. If the operator elects not to participate in the bulletin, that decision will be taken into consideration by GE in evaluating future product performance issues that may arise in the operator's fleet. |
| D. | Concurrent Requirements |
| None. |
| E. | Reason |
| (1) | Objective: |
| To introduce new parts and reduce significant events. |
| (2) | Condition: |
| Three engines have been found with loose or missing machine bolts from the fuel nozzle. |
| (3) | Cause: |
| It has been determined that at 34 of the 88 fuel nozzle bolt locations, where additional support brackets are mounted to the combustor diffuser nozzle (CDN) case, the current machine bolt length is insufficient to supply an adequate margin of proper thread engagement with the secondary retention feature of the threaded inserts. |
| (4) | Improvement: |
| The current fuel nozzle machine bolt is being replaced with a longer bolt at all 88 locations. This will ensure that, at the 34 locations identified with brackets, there will be sufficient thread engagement. Changing all 88 locations will eliminate any possible misassembly issues due to different machine bolt lengths. |
| (5) | Substantiation: |
| Substantiation is by comparative analysis. |
| F. | Approval |
| The data contained in this Service Bulletin has been reviewed by the FAA or authorized entity representing the FAA and the repair(s) and modification(s) herein comply with the applicable Aviation Regulations and are APPROVED for installation in the model(s) listed in this Service Bulletin. |
| G. | Manpower |
| No additional man-hours are required to comply with this Service Bulletin. |
| H. | Weight and Balance |
| The complete compliance with this Service Bulletin increases weight by 0.12 lb (0.05 kg). |
| I. | References (Use the latest version of these documents) |
| Deleted |
| GEK 112851, GEnx-1B Engine Manual (EM) |
| GEK 112862, GEnx-1B Cleaning, Inspection, and Repair Manual (CIR) |
| GEK 112864, GEnx-1B Engine Illustrated Parts Catalog (EIPC) |
| NOTE: |
|
| J. | Publications Affected |
| Deleted |
| GEK 112851, GEnx-1B Engine Manual (EM) |
| GEK 112862, GEnx-1B Cleaning, Inspection, and Repair Manual (CIR) |
| GEK 112864, GEnx-1B Engine Illustrated Parts Catalog (EIPC) |
| K. | Interchangeability |
| Replace the old bolt with the new longer bolt. Do not replace the new longer bolt with the old bolt. |
| L. | Software Accomplishment Summary |
| Not applicable. |
| 2. | MATERIAL INFORMATION |
| A. | Material - Price and Availability |
| (1) | Parts necessary to do this Service Bulletin: |
|
| *Part not supplied by GE Engine Services Distribution L.L.C. Procure through local purchase. |
| NP = Not Provisioned |
| NOTE: |
|
| (2) | Other Spare Parts: |
|
| NOTE: |
|
| (3) | Consumables: |
|
| B. | Industry Support Information |
| None. |
| C. | Configuration Chart |
|
| Operation Codes AD=Add RE=Replace RM=Remains |
| Change Codes 5=Qualified interchangeability. Refer to paragraph 1.K., Interchangeability. |
| Support Codes E=Old parts will be supplied, and can be used at other engine locations. |
| D. | Parts Disposition |
| Use serviceable old parts at other engine locations. |
| E. | Tooling - Price and Availability |
| None. |
| 3. | ACCOMPLISHMENT INSTRUCTIONS |
| A. | General |
| (1) | Remove the 88 machine bolts installed on the fuel nozzles. Refer to the GEnx-1B EM, 72-41-00, DISASSEMBLY 001, CONFIG 01, Subtask 72-41-00-040-024 or CONFIG 02, Subtask 72-41-00-040-044, Figure 1 of this Service Bulletin, and do as follows: |
| WARNING: |
|
| CAUTION: |
|
| (a) | Apply C02-026 penetrating oil to the bolts to be removed. Wait 15 minutes for C02-026 penetrating oil to soak into the joint. |
| (b) | Remove the 88 bolts that attach the fuel nozzles to the combustor case and discard them. |
| NOTE: |
|
| (c) | Do a visual inspection of the threaded inserts of the fuel nozzle pads in the combustion case as follows: |
| 1 | Thread damage is not permitted. |
| 2 | If thread damage exists, repair the insert. Refer to the GEnx-1B CIR, 72-41-01, REPAIR 001. |
| NOTE: |
|
| (2) | Install the new machine bolts (Figure 1) one at a time as follows: |
| WARNING: |
|
| (a) | Apply C02-097 lubricant on the threads of the new bolts. |
| (b) | Make sure that the bolthole on the support bracket aligns with the hole on the fuel nozzle pad. |
| (c) | Install the new machine bolt and torque it to 129 to 151 lb in. (14.5 to 17.0 Nm). |
| (d) | Do this procedure again for each affected bolt identified. |
