# CFM International Service Bulletin CFM56-7B 72-1054: Revision 02 - Rights: © CFM International. Filed by the FAA in regulations.gov docket FAA-2022-1405; AD 2023-05-05 incorporates this document by reference. Not covered by OpenAirDocs’ CC0 dedication. - Document: [CFM International Service Bulletin CFM56-7B 72-1054](https://openairdocs.org/service-documents/cfm/cfm56-7b-72-1054.md) - Title as filed: CFM56-7B Service Bulletin 72-1054-R02 - Pages: 23 - PDF: https://openairdocs.org/files/sha256/ec/51/ec51187e73fa6a81a933f69c9eb3b7150ef200e8313d3120951d79b99185b8b4 - Page: https://openairdocs.org/service-documents/cfm/cfm56-7b-72-1054/file/ec51187e73fa ## Text Some pages are 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 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb CFM PROPRIETARY INFORMATION The information contained in this document is CFM proprietary information and is disclosed in con fi- dence. It is the property of CFM and shall not be used, disclosed to others or reproduced without the express written consent of CFM, including, but wit hout limitation, it is not to be used in the creation, manufacture, development, or derivation of any repairs, modi fications, spare parts, design, or con fig- uration 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 w hole or in part. The information contained in this document may also be controlled by U.S. export control laws. Unauthorized export or re-export is prohibited. April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 1 of 23 ### Page 2 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb TRANSMITTAL INFORMATION REVISION 2 TO SERVICE BULLETIN 72-1054 Revision 2 is issued to update paragraphs 1., P LANNING INFORMATION,2 . ,M ATERIAL INFORMATION, and 3., A CCOMPLISHMENT INSTRUCTIONS. Revision 1 was issued January 15, 2020. The original was issued April 23, 2019. Revision bars in the left margin identify changes. 1. PLANNING INFORMATION A. Effectivity CFM56-7B20, -7B20/2, -7B20/3, -7B20E, -7B22, -7B22/2, -7B22/3, -7B22/3B1, -7B22/B1, -7B22E, -7B22E/B1, -7B24, -7B24/2, -7B24/3, -7B24/3B1, -7B24/B1, -7B24E, -7B24E/B1 CFM56-7B26, -7B26/2, -7B26/3, -7B26/3B1, -7B26/3B2, -7B26/3B2F , -7B26/3F , -7B26/B1, -7B26/B2, -7B26E, -7B26E/B1, -7B26E/B2, -7B26E/B2F , -7B26E/F , -7B27, -7B27/2 CFM56-7B27/3, -7B27/3B1, -7B27/3B1F , -7B27/3B3, -7B27/3F , -7B27/B1, -7B27/B3, -7B27A, -7B27A/3, -7B27AE, -7B27E, -7B27E/B1, -7B27E/B1F , -7B27E/B3, -7B27E/F The stationary high pressure turbine (HPT) inner stator seal (HPT inner stationary seal) P/N 1808M56G01 that has one of the serial numbers listed in T able 1 is affected by this Service Bulletin. T able 1. Suspect HPT Inner Stationary Seals HPT Inner Stationary Seal Serial Number Engine Serial Number (ESN) ALF019DL 877408 ALF04DL4 890317 ALF04DL5 891288 ALF04DL9 890371 ALF06DL1 892244 ALF098DL 876337 ALF10DL7 891300 ALF124GT 892676 ALF12DL6 890303 ALF13DL2 890425 ALF13DL9 890418 April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 2 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 3 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb HPT Inner Stationary Seal Serial Number Engine Serial Number (ESN) ALF155DL 876518 ALF158DL 876506 ALF16DL6 890324 ALF175DL 876538 ALF178DL 889130 ALF1DL10 888478 ALF1DL12 889479 ALF1DL13 575248 ALF1DL61 889860 ALF1DL96 888849 ALF224DL 876474 ALF243DL 876560 ALF255DL 889155 ALF263DL 876548 ALF267DL 876653 ALF276DL 876570 ALF27DL3 892212 ALF2DL16 888585 ALF2DL27 888592 ALF2DL55 888606 ALF2DL76 889697 ALF30DL5 890662 ALF315DL 876598 ALF32DL4 890457 ALF32DL9 890858 ALF331DL 876552 ALF33DL2 890436 ALF343DL 876639 ALF36DL9 875258 ALF376DL 876671 ALF380DL 888125 April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 3 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 4 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb HPT Inner Stationary Seal Serial Number Engine Serial Number (ESN) ALF391DL 876693 ALF3DL17 888636 ALF3DL18 888635 ALF3DL20 889677 ALF3DL45 888651 ALF3DL48 888821 ALF3DL67 888717 ALF3DL80 888711 ALF3GT34 697137 ALF3GT40 892118 ALF410DL 877164 ALF420DL 874120 ALF42DL0 890670 ALF42DL5 891538 ALF43DL3 890516 ALF446DL 888128 ALF44DL1 890535 ALF46DL4 874368 ALF48DL6 890668 ALF49DL5 890700 ALF4DL10 890523 ALF4DL35 888748 ALF4DL52 575356 ALF4DL70 888827 ALF4DL87 888806 ALF50DL4 890669 ALF53DL0 890901 ALF53DL8 890587 ALF548DL 889219 ALF5DL41 888866 ALF5DL71 888892 April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 4 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 5 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb HPT Inner Stationary Seal Serial Number Engine Serial Number (ESN) ALF5DL75 888850 ALF5DL79 889751 ALF5DL84 874209 ALF60DL3 890749 ALF61DL2 890783 ALF62DL5 890748 ALF63DL6 890656 ALF65DL9 890639 ALF66DL7 891647 ALF6DL25 894454 ALF6DL96 876689 ALF6DL99 888918 ALF709DL 888233 ALF70DL4 890692 ALF70DL6 890708 ALF73DL8 890684 ALF745DL 888269 ALF746DL 888284 ALF74DL2 891305 ALF762DL 888417 ALF78DL9 890848 ALF7DL15 575476 ALF81DL7 891794 ALF826DL 889432 ALF836DL 888400 ALF83DL4 890733 ALF87DL8 890810 ALF89DL3 891539 ALF8DL07 890110 ALF8DL14 575477 ALF8DL16 575469 April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 5 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 6 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb HPT Inner Stationary Seal Serial Number Engine Serial Number (ESN) ALF8DL38 575470 ALF90DL6 876544 ALF90DL8 891859 ALF915DL 888440 ALF91DL4 890853 ALF91DL7 890860 ALF934DL 888390 ALF943DL 888447 ALF961DL 888562 ALF965DL 888543 ALF983DL 575249 ALF986DL 888441 ALF987DL 890179 ALF990DL 888477 ALF991DL 889536 ALF9DL62 890202 ALF9DL81 875134 ALF9DL84 891273 ALF9DL90 890339 ALF9DL98 890222 ALFDL085 890504 ALFDL140 874390 ALFDL143 874374 ALFDL149 874388 ALFDL152 875613 ALFDL165 875398 ALFDL180 874526 ALFDL230 875578 ALFDL245 874628 ALFDL337 874564 ALFDL355 875612 April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 6 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 7 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb HPT Inner Stationary Seal Serial Number Engine Serial Number (ESN) ALFDL365 874285 ALFDL383 890734 ALFDL418 889170 ALFDL439 890986 ALFDL455 874219 ALFDL479 875795 ALFDL537 877511 ALFDL544 874721 ALFDL546 874819 ALFDL549 894750 ALFDL551 874870 ALFDL554 876460 ALFDL577 874928 ALFDL578 874803 ALFDL593 874773 ALFDL597 874760 ALFDL603 875915 ALFDL628 874850 ALFDL641 875838 ALFDL654 875861 ALFDL657 874877 ALFDL665 877152 ALFDL688 875862 ALFDL689 876461 ALFDL693 874869 ALFDL699 874829 ALFDL707 874863 ALFDL721 779658 ALFDL726 876144 ALFDL736 874913 ALFDL747 874918 April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 7 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 8 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb HPT Inner Stationary Seal Serial Number Engine Serial Number (ESN) ALFDL793 876109 ALFDL828 876181 ALFDL864 877257 ALFDL885 890806 ALFDL891 876243 ALFDL911 876239 ALFDL978 876253 ALFDL981 779731 ALFG7503 893353 ALFGT030 890925 ALFGT096 876312 ALFGT120 890937 ALFGT128 890970 ALFGT174 893194 ALFGT293 893164 ALFGT332 890743 ALFGT386 892243 ALFGT410 888908 ALFGT570 893342 ALFGT572 893341 ALFGT581 892358 ALFGT601 892356 ALFGT608 892381 ALFGT767 892477 ALFJW093 803811 ALFKK208 874102 ALFKK264 874112 ALFKK412 890458 ALFKK451 874127 ALFKK471 874352 April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 8 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 9 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb HPT Inner Stationary Seal Serial Number Engine Serial Number (ESN) ALFKK556 875942 ALFKK558 875175 ALFKK596 874422 ALFKK602 875340 ALFKK614 875199 ALFKK642 874217 ALFKK644 874212 ALFKK668 888901 ALFKK686 874435 ALFKK696 875245 ALFKK725 890592 ALFKK727 875334 ALFKK737 875287 ALFKK738 874268 ALFKK757 875310 ALFKK772 874286 ALFKK824 874336 ALFKK828 875344 ALFKK904 874460 ALFKK915 888883 ALFKK950 875527 ALFKK990 875586 ALFKL025 877153 ALFKL047 874643 ALFKL109 874736 ALFKL130 874792 ALFKL134 875802 ALFKL136 875785 ALFKL140 875796 ALFKL147 875904 ALFKL160 874901 April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 9 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 10 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb HPT Inner Stationary Seal Serial Number Engine Serial Number (ESN) ALFKL202 874924 ALFKL212 874969 ALFKL233 874940 ALFKL270 874955 ALFKL304 876105 ALFKL326 890844 ALFKL346 876148 ALFKL348 876135 ALFKL363 876203 ALFKL383 876194 ALFKL421 888708 ALFKL437 877422 ALFKL445 877587 ALFKL481 876467 ALFKL488 890737 ALFKL511 575199 ALFKL540 876420 ALFKL548 876448 ALFKL558 874389 ALFKL563 876468 ALFKL589 876495 ALFKL604 876502 ALFKL609 876501 ALFKL615 875220 ALFKL628 876494 ALFNB126 895953 ALFPB985 802195 TRIT1077 877695 TRIT1079 779873 TRIT1108 876623 TRIT1115 876652 April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 10 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 11 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb HPT Inner Stationary Seal Serial Number Engine Serial Number (ESN) TRIT1126 888604 TRIT1161 876649 TRIT1262 876662 TRIT1266 779894 TRIT1269 876687 TRIT1453 888436 TRIT3209 888531 TRIT3210 575252 TRIT3252 888446 TRIT3262 875476 TRIT3590 874227 TRIT3627 888183 TRIT3872 888567 TRIT3886 889598 TRIT3920 888560 TRIT3930 888589 TRIT3932 888605 TRIT3939 888559 TRIT4633 875186 TRIT4947 888760 TRIT4959 888753 TRIT5067 888756 TRIT5636 890838 TRIT5645 890886 TRIT5723 890400 TRIT6637 890707 These serial numbers are the best available data. NOTE: The ESNs listed in T able 1 are the last known location for a given HPT inner stationary seal. This information is intended to help determine the current location of the HPT inner stationary seal. April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 11 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 12 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb B. Description This Service Bulletin provides actions needed on the affected HPT inner stationary seal with its serial number listed in T able 1 of paragraph 1.A., E ffectivity. C. Compliance Category 3 CFM recommends that you do this Service Bulletin at the next shop visit of the engine as follows: The following quick turn shop visit type is exempt from compliance to this Service Bulletin: - The removal of a disk, hub, or spool for purposes other than LLP expiration, and which does not require the separation of a major module flange. Impact A This recommendation is to address a condition that may affect Flight Safety. NOTE 1: This Service Bulletin can be accomplished in shop. This Service Bulletin is offered to improve the reliability or performance of your CFM 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 decisi on will be taken into consideration by CFM in evaluating future product performance issues that may arise in the operator’s fleet. NOTE 2: Some steps in paragraph 3., A CCOMPLISHMENT INSTRUCTIONS are identified as Required for Compliance (RC). If this Service Bulletin is mandated by an Airworthiness Dir ective (AD), the steps identi fied as RC must be done to comply with the AD. Steps not identi fied with RC are recommended and may be deviated from; done as a part of other actions; or done with accepted methods different from those given in the Service Bulletin if the RC steps can be done and the airplane returned to a serviceable condition. D. Concurrent Requirements None. E. Reason (1) Objective: T o repair the HPT inner stationary seal that may have a condition that could affect flight safety. April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 12 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 13 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb (2) Condition: The affected HPT inner stationary seal may have a condition, generated during a field replacement of honeycomb, which could lead to a localized separation of the replaced honeycomb. Separated honeycomb could affect the life of the rotating air HPT front seal. (3) Cause: The affected HPT inner stationary seals, at the time of the honeycomb replacement, may not have received the correct braze heat treat cycle specified in the repair. (4) Improvement: The braze condition on the HPT inner stationary seal honeycomb will no longer be suspect if the honeycomb is replaced after December 31, 2012. (5) Substantiation: Substantiation is by analysis and fleet experience. F. Approval The technical content of this Service Bulletin is approved by the FAA and under the Authority of DOA No. EASA.21J.086. G. Manpower No additional man-hours are required to comply with this Service Bulletin. H. Weight and Balance Weight and balance are not changed. I. References (Use the latest version of these documents) CFM56-7B Engine Shop Manual (ESM), CFMI-TP .SM.10 CFM56-7B Illustrated Parts Catalog (IPC), CFMI-TP .PC.14 EASA Airworthiness D irective (AD) 2020-0044 FAA Airworthiness Directive (AD) 2021-10-09 J. Publications Affected None. K. Interchangeability Not applicable. April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 13 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 14 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb L. Software Accomplishment Summary Not applicable. 2. MATERIAL INFORMATION A. Material - Price and Availability (1) Parts necessary to do this Service Bulletin: None. (2) Other Spare Parts: Part Number Qty/ Eng Part Name Unit ($) Price Pkg Qty Lead Time Days 1808M56G01 (1) Seal, Stationary HPT Inner Stator 132,100.00 (1) 5 NOTE: Prices are provided for planning purposes and are subject to change. (3) Consumables: None. B. Industry Support Information None. C. Configuration Chart None. D. Parts Disposition Report information listed on T able 3 to the CFM Customer Support Center (CSC) or Fleet Support to the following address: April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 14 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 15 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb T able 2. CFM Contact Information CFM SA ZONE CFM Inc. Zone Customer Support Center: http://mycfmportal.com Widget AskCFM OR E-mail: cfm.csc@safrangroup.com OR PSE CFM SAFRAN Aircraft Engines Site de MELUN MONTEREAU BP 1936 - 77019 Melun Cedex FRANCE OR Phone: +33 1 64 14 88 66 F a x : + 3 316 41 48 76 5 GE Aviation Fleet Support: http://www.geaviation.com/support OR E-mail (USA): aviation. fleetsupport@ge.com E-mail (China and Asia): aviation. fleet- support.cn@ge.com OR GE Aviation M/D Rm. 285 One Neumann Way OH 45215 USA OR USA Phone: 877-432-3272 International Phone: (513) 552-3272 China and Asia Phone: +86 21 38777666 For engines applicable to the steps in paragraph 3., A CCOMPLISHMENT INSTRUCTIONS marked below, report the following data to CFM: T able 3. Data Needed Data Needed Step 3.A.(1)(a) Step 3.C.(2) Step 3.C.(3) ESN Applicable Applicable Applicable HPT inner stationary seal serial number Applicable Applicable Applicable Shop where honeycomb was replaced Applicable -- -- Date and engine cycle since new (CSN) when the honeycomb was replaced or when the part was removed from service Applicable -- -- Inspection report of the HPT inner stationary seal (if available) Applicable -- -- April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 15 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 16 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb Data Needed Step 3.A.(1)(a) Step 3.C.(2) Step 3.C.(3) Part number and serial number of the rotating air HPT front seal -- Applicable -- Photos of the honeycomb separation -- Applicable -- Deleted Deleted Deleted Deleted Discard of the No. 3 ball bearing -- Applicable -- Inspection results of the HPT rotor -- -- Applicable Date and CSN of the Service Bulletin compliance Applicable Applicable Applicable Parts that are speci fied in step 3.C.(2) of paragraph 3., A CCOMPLISHMENT INSTRUCTIONS must be sent back to CFM. Please contact your Field Service Engineer (FSE) or Fleet Support for detailed instructions on where to return the removed HPT inner stationary seal and rotating air HPT front seal. E. Tooling - Price and Availability None. 3. ACCOMPLISHMENT INSTRUCTIONS A. General (1) For a suspect HPT inner stationary seal (Figure 1) that had a honeycomb replaced as speci fied in the CFM56-7B ESM, 72-41-03, REPAIR 003 after December 31, 2012, or that was removed from service, do as follows: (a) Report information to CFM. Refer to paragraph 2.D., P arts Disposition. (b) No action is necessary. Con firmation of repair or removal from service is considered the terminating action for this Service Bulletin. (2) For a suspect HPT inner stationary seal (Figure 1) which did not have a honeycomb replacement as speci fied in the CFM56-7B ESM, 72-41-03, REPAIR 003 after December 31, 2012, continue with paragraph 3.B., Removal. B. Removal (1) Remove the HPT rotor. Removal instructions have not changed. Refer to the CFM56-7B ESM, 72-00-52, REMOVAL. April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 16 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 17 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb (2) Remove the combustion assembly. Removal instructions have not changed. Refer to the CFM56-7B ESM, 72-00-41, REMOVAL 001. (3) Refer to the CFM56-7B ESM, 72-41-00, DISASSEMBLY for HPT inner stationary seal removal instructions. (4) RC - Remove the suspect HPT inner stationary seal (Figure 1). (5) Continue with paragraph 3.C., I nspection. C. Inspection (1) RC - Do an inspection of the suspect HPT inner stationary seal (Figure 1) for honeycomb condition. NOTE 1: Honeycomb separation is described as a section of missing honeycomb if it measures as follows: – Radially, more than 0.30 inch (7.6 mm). – Axially, more than 0.75 inch (19.1 mm). – Circumferentially, any amount. NOTE 2: Missing honeycomb is caused by an unsatisfactory braze quality condition that creates areas where the honeycomb is separated from the backing plate. (2) If you see honeycomb separation (Figure 1), then remove the suspect HPT inner stationary seal and do as follows: (a) Contact CFM if the information of the honeycomb separation is uncertain. Refer to paragraph 2.D., P arts Disposition. (b) Send the HPT inner stationary seal (Figure 1) back to CFM. Please contact your FSE or Fleet Support for detailed instructions on where to return the removed HPT inner stationary seal. (c) Refer to the CFM56-7B ESM, 72-52-00, DISASSEMBLY for HPT rotating front seal removal instructions. (d) RC - Remove the rotating air HPT front seal (Figure 2). (e) Send the removed rotating air HPT front seal (Figure 2) back to CFM. Please contact your FSE or Fleet Support for detailed instructions on where to return the removed rotating air HPT front seal. (f) Refer to the CFM56-7B ESM, 72-52-00, DISASSEMBLY for HPT blade removal instructions. (g) RC - Remove the HPT blades (Figure 2) from the HPT rotor. April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 17 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 18 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb 1 If you do not plan to return the HPT blade set to service, discard the blade set. 2 If you do plan to return the HPT blade set to service, return the HPT blade set to an approved repair source for overhaul. NOTE: Overhauled HPT blades can be returned to service. (h) Refer to the CFM56-7B ESM, 72-61-00, DISASSEMBLY for No. 3 ball bearing removal instructions. (i) RC - Remove and discard the No. 3 ball bearing (Figure 3). (j) Report the information of the removed HPT inner stationary seal (Figure 1) and rotating air HPT front seal (Figure 2) to CFM. Refer to paragraph 2.D., P arts Disposition (k) Continue with paragraph 3.D., I nstallation. (3) If you do not see honeycomb separation as speci fied in step 3.C.(2), then do as follows: (a) Report to CFM unusual honeycomb condition that does not look like the normal wear caused by mating rotating air HPT front seal (Figure 2) teeth. (b) RC - If you do not plan to discard the HPT inner stationary seal, replace the honeycomb (Figure 1). (c) Refer to the CFM56-7B ESM, 72-41-03, REPAIR 003. (d) Do an inspection of the exposed areas as speci fied in the applicable ESM inspection criteria. (e) Report the information to CFM. Refer to paragraph 2.D., P arts Disposition. (f) Continue with paragraph 3.D., I nstallation. D. Installation (1) Install the repaired or new HPT inner stat ionary seal (Figure 1). Installation instructions have not changed. Refer to the CFM56-7B ESM, 72-41-00, ASSEMBLY . NOTE: A serviceable HPT inner stationary seal is necessary if the removed suspect HPT inner stationary seal was sent back to CFM as speci fied in step 3.C.(2)(b). (2) Install a serviceable rotating air HPT front seal (Figure 2). Installation instructions have not changed. Refer to the CFM56-7B ESM, 72-52-00, ASSEMBLY and do as follows: April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 18 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 19 ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb (a) Install the HPT rotor blades (Figure 2) if you removed or replaced them. Installation instructions have not changed. Refer to the CFM56-7B ESM, 72-52-00, ASSEMBLY . (3) Install the combustion assembly. Installation instructions have not changed. Refer to CFM56-7B ESM, 72-00-41, INSTALLATION. (4) Install the HPT rotor module. Installation instructions have not changed. Refer to CFM56-7B ESM, 72-00-52, INSTALLATION. (5) Install the No. 3 ball bearing (Figure 3) if it was removed. Installation instructions have not changed. Refer to CFM56-7B ESM, 72-61-00, ASSEMBLY . April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 19 CFM Des ignated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 20 (OCR) cim SERVICE BULLETIN THE POWER CFM56-7B OF FLIGHT ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb MIDFLANGE 00006 AFT FLANGE 0000 COMBUSTION DIFFUSER CASE FORWARD HPT INNER STATIONARY 1 00000000 SEAL 6002571-00 Location of HPT Inner Stationary Seal and Honeycomb Figure 1, ( Sheet 1 of 2) April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 20 CFM Designated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 21 (OCR) letm SERVICE BULLETIN THE POWER CFM56-7B. OF FLIGHT ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb DETAIL A HPT INNER STATIONARY FORWARD SEAL RADIAL DEPTH HONEYCOMB SECTION VIEW B HONEYCOMB SECTION WITH MISSING HONEYCOMB SECTION HONEYCOMB WITH NORMAL WEAR AXIAL LENGTH CIRCUMFERENTIAL LENGTH FORWARD HPT INNER STATIONARY SEAL 6002572-00 Location of HPT Inner Stationary Seal and Honeycomb Figure 1, ( Sheet 2) April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 21 CFM Designated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 22 (OCR) letm SERVICE BULLETIN THE POWER CFM56-7B. OF FLIGHT ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb HPT ROTOR BLADE ROTATING AIR HPT FRONT SEAL 98883808 FORWARD SECTION A-A ROTATING AIR HPT FRONT SEAL FORWARD 6002060-00 Location of Rotating Air HPT Front Seal and HPT Rotor Blades Figure 2 April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 22 CFM Designated: - CONFIDENTIAL Subject to the restrictions on the media ### Page 23 (OCR) cim SERVICE BULLETIN THE POWER CFM56-7B. OF FLIGHT ENGINE - Combustion Assembly (72-41-00) - Repair of HPT Inner Stationary Seal Honeycomb NO. 3 BALL BEARING FORWARD HORIZONTAL BEVEL GEAR NO. 3 BEARING LOCKING NUT RADIAL BEVEL GEAR 6002573-00 Location of No. 3 Ball Bearing Figure 3 April 23, 2019 CFM56-7B S/B 72-1054 Revision 02, August 10, 2022 PAGE 23 CFM Designated: - CONFIDENTIAL Subject to the restrictions on the media --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). 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