Continental MSB 23-01: Revision A

ISSUED REVISED DOC NO REVISION PAGE 2023/02/13 2023/02/16 MSB23-01 A 1 of 8 ©2023 Continental Aerospace Technologies, Inc. P.O. Box 90 Mobile, AL 251.436.8299 CATEGORY 1 MSB23-01A

TECHNICAL PORTIONS

FAA APPROVED CONTINENTAL AEROSPACE TECHNOLOGIES™

MANDATORY SERVICE BULLETIN Subject Matter of This Document may be Incorporated, in Whole or in Part, in an FAA Issued Airworthiness Directive SUBJECT: Crankshaft counterweights PURPOSE: Inspect affected crankshafts for proper counterweight installation.

COMPLIANCE: For Engines with less than 200 operating hours:  Accomplish immediately; an additional five flight hours acceptable to move to a maintenance facility with minimum e ssential crew, if necessary. Compliance time begins upon Service Bulletin receipt For Engines with more than 200 operating hours: No further action required MODELS AFFECTED: New and rebuilt Continental Aerospace Technologies aviation gasoline (AvGas) engines or crankshaft assemb lies with serial numbers listed in Appendix 1 or Appendix 2:  IO-360-A, AB, AF, C, CB, D, DB, E, ES, G, GB, H, HB, J, JB, K, KB;  LTSIO-360-E, EB, KB, RB;  TSIO-360-A, AB, B, BB, C, CB, D, DB, E, EB, G, GB, H, HB, JB, KB, LB, MB, RB, SB;  O-470-A, B, E, G, H, J, K, L, M, N, R, S, T, U;  IO-470-D, E, G, H, J, K, L, M, N, P, R, S, T, U, V , VO;  GTSIO-520-C, D, H, K, L, M, N, S;  IO-520-A, B, BA, BB, C, CB, D, E, F, J, K, L, M, MB;  LTSIO-520-AE;  TSIO-520-A, AE, AF, B, BB, BE, C, CE, D, DB, E, EB, G, H, J, JB, K, KB, L, LB, M, NB, P, R, T, UB, VB, WB; IO-550-A, B, C, D, E, F, G, L, N, P, R;  TSIO-550-A, B, C, E, G, K, N;  TSIOL-550-A, B, C;  TSIOF-550-K.

I. GENERAL INFORMATION Continental discovered a potential assembly error affecting approximately 2000 crankshaft assemblies. It is possible one or more counterw eight retaining rings were not properly seated in the crankshaft counterwei ght groove. This condition coul d allow the counterweight to depart from the crankshaft during engine operation resulting in catastrophic engine damage.

II. SCOPE The engines and crankshaft as semblies affected by this bulletin are identified by Serial Number in Appendix 1 (engines) and Appendix 2 (crankshaft assemblies sold as replacement parts). Only the engine or cra nkshaft assembly seri al numbers listed in the two tables are subject to inspection. Inspectio n is not required on engines and crankshaft assemblies not included in the two tables.

ISSUED REVISED DOC NO REVISION PAGE 2023/02/13 2023/02/16 MSB23-01 A 2 of 8 The engine data plate is mounted to the 1-3-5 side of the engine. Inspect the serial number on the data plate to determine if the engine is affected by this service bulletin. The crankshaft serial number is stamped in the perimeter of the propeller flange.

III. ACTION REQUIRED

1. Locate the affected crankshaft assemblies:

a. For spare crankshaft assemb lies, collect affected spare crankshaft assemblies from protected storage and relocate to a workbench with V-blocks and a surface plate and proceed to Section III, step 2.

b. For crankshaft assemblies installed in engines, remove cylinders from the odd (1-3-

5) side of the crankcase according to the in structions in the primary Instructions for Continued Airworthiness (ICA ). The number of cylinders required to be removed for inspection is determined by the number of and location of the counterweights on the crankshaft assembly. Crankshaft assemblies differ by engine model.

CAUTION: Cylinder removal from the crankcase relieves throughbolt preload. Use of torque plates or spacers to maintain tension on the crankcase is recommended befo re rotating th e crankshaft with cylinders removed.

2. After cylinder removal, rotate the cra nkshaft for best access to the counterweight plates. Inspect crankshaft counterweights w ith an inspection mirror and flashlight for security and proper installation of the reta ining clip in the counterweight groove. The following illustrations, as well as detailed disassem bly, inspection, and assembly instructions are contained in M-0, Section 10-9.1.

a. If a counterweight retaini ng ring, plate, or pin is miss ing, terminate the inspection and remove the engine for disassembly. Inspect and repair, as necessary.

b. Verify the installed retaining rings are installed in counterweight grooves and match the installed specifications in Figure 2 or Figure 3.

1) Refer to the installation instructions in M-0, Section 10-9.1.5 for “Crankshaft Counterweight Bushing Replacement” step 6. instructions.

2) Consult online illustrated parts ca talogs for assembly part numbers.

NOTE: The leading edge of the gage must contact the surface of the retaining plate squarely for an acc urate measurement. Slide the gage between the retaining ring ears until the gage contacts the edge of the counterweight. Blue Dykem may be present on the counterweight assembly or the counterweight plate, or the retaining ring; removing excess Dykem is acceptable to complete the inspection. There may be slight resistance when trying to insert the gage - this is acceptable and expected.

Engine Model Cylinders to be removed O-470-R and  IO/LTSIO/TSIO-360 1 GTSIO-520 1, 3, and 5 All others 1 and 3

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3) Measure installed counterweight re taining ring minimum gap (Figure 1) between ears with a copy of the gage block manufactured to meet the specifications in Figure 4 or Figure 5. All three conditions specified in Figure 1 must be met. Inspection gages are available to borrow upon request from Continental or the tool may be locally manufactured according to the specifications provided in Figure 4 or Figure 5.

Figure 1. Gage Inserted to Measure Retaining Ring Gap

WARNING

DO NOT INSTALL LOOSE FITTING PRESS BUSHING FLUSH

RETAINER PLATES IN COUNTERWEIGHTS WITH THESE SURFACES

POSITION BUSHING

LEAD-IN TOWARD

RETAINER PLATES FEATURE AN COUNTERWEIGHT

EXTRUDED POINT FOR AN INTERFERENCE DURING INSTALLATION

FIT (EXAGGERATED FOR CLARIFICATION) SEE "A" DIAMETER FOR BUSHING I.D. PIN PLATE

RETAINING RING

INSTALL RETAINING RING WITH SHARP EDGE (FLAT INSTALL RETAINING RING

WITH GAPS TOWARD SURFACE) FACING

CRANKSHAFT CENTERLINE OUTBOARD

AS SHOWN

INSPECT THESE AREAS

FOR PLATE WEAR

MINIMUM GAP BETWEEN RETAINING RING EARS:

ALL 360 ENGINES = 0.212" FOR 470, 10520, L/TSIO520, 10550, TSI0550, TSIOF550, AND TSIOL550 ENGINES = 0.179" Figure 2. Counterweight Inspection (Applicable to 360, 470, 10520, L/TSIO-520, and 550 Series Engines Only) Figure 3 is NOT applicable to GTSIO-520 (See Figure 3) INSTALL RETAINING RING EARS TOWARD •MINIMUM GAP BETWEEN

THE CRANKSHAFT CENTERLINE RETAINING RING AS SHOWN EARS - 0.212 INCH GTSIO-520 COUNTERWEIGHT RETAINER PLATES HAVE A 0.0037 TO 0.0062 LOOSE

FIT IN THE COUNTERWEIGHT

RETAINER PLATE BORE Figure 3. Counterweight Inspection (Applicable to GTSIO-520 Only)

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AEROSPACE TECHNOLOGIES

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c. If all the components appear to be installed but the counterweight retaining ring does not exhibit the proper orientatio n or the minimum distance between the retaining ring ears is not met, attempt to reposition or reseat the retaining ring with retaining ring pliers or a small drift or punch.

NOTE: If counterweight retainin g ring(s) are removed from the counterweight, new retaining ring(s) are required for reassembly.

d. If repositioning or reseat ing the retaining rings is not successful, remove the retaining rings, retaining plat es and the counterweight pi ns from one side of the counterweight and remove the counterweight from the crankshaft hanger blade to determine the cause of non-conformity using the instructions in Section 10-9.1.

NOTE: Record the position from which the counterweight pins are removed. The counterweight pin pa rt numbers determine the magnitude of vibration the counterweight is desi gned to inhibit. Installing incorrect pin in the counterweight assembly could increase engine vibration.

3. Rotate the crankshaft, as necessary, to gain access to the remaining counterweight assemblies on the crankshaft until all counterweight assemblies have been inspected and proper installation of the counterweight plates an d retaining rings has been verified.

4. Re-install cylinders according to th e instructions in the primary ICA.

5. Perform an engine start and ground run-up according to the AFM/POH to verify engine operation after installation and perform a engine visual leak check.

6. Record compliance with this service bulletin on crankshaft s installed in the engine in the engine log book. For repl acement crankshafts, apply a 0.375” dot of white enamel paint to the outer face of each counterweight after completing the inspection.

IV. TOOL DRAWINGS

0.30 | Ø0.10

4.00 179"

0.25 1800 1790 10.40 4142 STEEL BREAK ALL SHARP EDGES (4140 IS PERMISSABLE İF HARDENED 28-32 ROCKWELL C) .010" MAX AND REMOVE BURRS Figure 4. 0.179 Inch Gage (470, 10520, L/TSIO-520, and 550 Series Engines Only)

0.30 Ø0.10 THRU 4.00 .212"

0.22

(0.40 00 4142 STEEL BREAK ALL SHARP EDGES (4140 IS PERMISSABLE IF .010" MAX AND REMOVE BURRS HARDENED 28-32 ROCKWELL C) Figure 5. 0.212 Inch Gage (IO/LTSIO/TSIO-360 and GTSIO-520 Series Engines Only)

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AEROSPACE TECHNOLOGIES

ISSUED REVISED DOC NO REVISION PAGE 2023/02/13 2023/02/16 MSB23-01 A 7 of 8 V . WARRANTY The actions required to comply with this Service Do cument are covered, up to the Eligible Allowance provided for reimbursement, as shown below. Standard warranty practices apply. Visit the Continental web site at www.continental.aero to obtain copies of Continental Warranty Policies.

Please provide details of discrepancy with the completed compliance form as verification of nonconformity. Photos are preferred, a detailed description is acceptable.

Complete and email a copy of the linked Compliance Form, along with a copy of the work invoice and a copy of the repair agency’s W-9, for reimbursement. To prevent delays in reimbursement processing, the following inform ation MUST be included in th e “Details and Description of Troubleshooting” section of the compliance form.

1. Non-conformity found? Yes or No

2. If yes, what condition of non-conformity was found?

Continental reserves the right to request copies of invoices and maintenance records to verify warranty applicability.

Allowances/Reimbursements Continental has established a dedicated telephone line and em ail address to field questions regarding this service document.

Direct Dial ................. 251-441-4460 Main Line ................. 251-308-9100 - Option 9 Email: ........................ MSB23Support@continental.aero If unable to reach our representatives using the dedicated lines, the numbers below are also active:

1.888.826.5465 Toll Free in the United States +1.251.436.8299 International Callers Eligible Allowances for Reimbursement (not installed in engine) Labor Hours1

1. at published shop rate 1 Inspect crankshaft counterweight reta ining rings (per counterweight) 0.15 2 Reposition, Reseat, or Remove and Install Crankshaft Counterweight Assemblies (per counterweight assembly) 0.25 Eligible Allowances for Reimbursement (installed in aircraft) Labor Hours1

1. at published shop rate 1 Remove and install one cylinder (see table in Section III) 10.0 Remove and install two cylinders (see table in Section III) 18.0 Remove and install three cylinders (see table in Section III) 22.0 2 Inspect crankshaft counterweight reta ining rings (per counterweight) 0.25 3 Reposition, Reseat, or Remove and Install Crankshaft Counterweight Assemblies (per counterweight assembly) 0.50

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ISSUED REVISED DOC NO REVISION PAGE 2023/02/13 2023/02/16 MSB23-01 A 1 of 30 Appendix 1. Affected Engine Serial Numbers Affected engines and crankshafts are listed below, sorted by en gine serial number and grouped under engine model headings.

0470L Engine Model Engine Serial No. Crankshaft Serial No.

1042828 N12KA175 0470R Engine Model Engine Serial No. Crankshaft Serial No.

1041340 N21AA291 1041398 N21AA295 1041437 N21AA293 1041530 N21AA285 1041531 N21AA296 1041560 N21AA281 1041561 N21AA274 1041562 N21AA280 1041564 N21AA297 1041938 N21BA059 1041974 N21BA071 1042336 N21BA070 1043161 N21FA203 1043162 N21FA210 1043165 N21FA211 1043181 N21FA190 1043246 N21FA197 1043271 N21FA169 1043688 N21KA247 1043696 N21KA249 1043705 N21KA255 1043799 N21KA259 1043800 N22CA193 1043858 N22CA197 1043867 N22CA198 1043945 N22CA199 1043981 N21KA228 1044021 N22CA217 1044024 N22CA220 1044382 N22CA228 1044394 N22CA221 1044395 N22CA230 1044396 N22CA219 1044444 N22CA218 1044448 N22CA216 1044931 N22CA226 0470S Engine Model Engine Serial No. Crankshaft Serial No.

1041563 N21AA287 1041567 N21BA066 1043272 N21FA213 1043668 N21KA254 1043671 N21KA265 0470U Engine Model Engine Serial No. Crankshaft Serial No.

1041937 N21BA076 1043207 N21FA167 1043208 N21FA175 1043209 N21FA170 1043252 N21FA166 1043305 N21FA188 1043384 N21FA182 1043385 N21KA241 1043664 N21KA223 1043684 N21KA235 1043706 N21KA234 1043713 N21KA244 1043760 N21KA236 1044012 N21FA177 1044389 N22CA205 GTSI0520H Engine Model Engine Serial No. Crankshaft Serial No.

1042536 N21CA007 1042575 N21CA034 0470R Engine Model Engine Serial No. Crankshaft Serial No.

ISSUED REVISED DOC NO REVISION PAGE 2023/02/13 2023/02/16 MSB23-01 A 2 of 30 GTSI0520L Engine Model Engine Serial No. Crankshaft Serial No.

1042500 N21CA009 1042499 N21CA035 I0360CB Engine Model Engine Serial No. Crankshaft Serial No.

1043507 N07HA042 1044728 N22DA076 I0360DB Engine Model Engine Serial No. Crankshaft Serial No.

1044430 N22DA066 I0360ES Engine Model Engine Serial No. Crankshaft Serial No.

1042000 N20KA258 1043551 N21GA029 1044403 N22DA065 1044404 N21GA023 1044435 N22DA077 1044443 N22DA057 1044447 N22DA072 I0360GB Engine Model Engine Serial No. Crankshaft Serial No.

1043390 N21GA050 I0360HB Engine Model Engine Serial No. Crankshaft Serial No.

1040497 F019916N 1043391 N21GA010 I0360KB Engine Model Engine Serial No. Crankshaft Serial No.

1041994 N21BA099 1042402 N21BA109 1044538 N22DA064 1044687 N22DA058 I0470L Engine Model Engine Serial No. Crankshaft Serial No.

1043227 N21FA224 1043241 N21FA216 1043249 N20FA199 1043250 N20FA198 1043251 N20FA195 1043670 N22BA016 1043784 N22BA014 1043785 N22BA015 1043786 N22BA010 I0470N Engine Model Engine Serial No. Crankshaft Serial No.

1043589 N21FA225 1043789 N22BA012 1043812 N22BA025 I0520A Engine Model Engine Serial No. Crankshaft Serial No.

1044709 N21KA063 I0520BB Engine Model Engine Serial No. Crankshaft Serial No.

1041898 N21BA332 1041908 N21BA348 1041969 N21BA331 1043024 N21DA204 1043206 N21DA195 1043918 N21KA147 1044035 N21KA140 1044046 N21KA144 1044586 N22IA132 1044799 N22IA170 I0520CB Engine Model Engine Serial No. Crankshaft Serial No.

1041894 N21BA313 1041895 N21BA298 1043163 N21DA200 1043164 N21DA202

ISSUED REVISED DOC NO REVISION PAGE 2023/02/13 2023/02/16 MSB23-01 A 3 of 30 1044042 N21DA208 1044043 N21KA149 1044581 N22IA160 I0520D Engine Model Engine Serial No. Crankshaft Serial No.

1042189 N21AA248 1043260 N21FA098 1043587 N21AA250 1043639 N21AA227 1043787 N22CA080 1043882 N22CA062 1044222 N22FA121 1044234 N22CA136 1044467 N22FA158 1044695 N22CA138 1044704 N21KA091 1044708 N22FA146 1044711 N21KA092 1044712 N21KA086 1044809 N22LA008 1044878 N21KA071 I0520E Engine Model Engine Serial No. Crankshaft Serial No.

1043562 N21AA260 I0520F Engine Model Engine Serial No. Crankshaft Serial No.

1042342 N21AA229 1043268 N21FA072 1043674 N21FA074 1043725 N22CA103 1043779 N22CA063 1043788 N22CA086 1043801 N22CA065 1043827 N22CA107 1043906 N22CA131 1044175 N22FA125 I0520CB Engine Model Engine Serial No. Crankshaft Serial No.

1044178 N22FA147 1044333 N22FA134 1044557 N21AA225 1044629 N22FA118 1044694 N21KA089 1044714 N21KA088 1044772 N21KA093 1044825 N22LA009 I0520L Engine Model Engine Serial No. Crankshaft Serial No.

1041465 N21AA261 1043261 N21FA084 1044215 N22FA123 I0520MB Engine Model Engine Serial No. Crankshaft Serial No.

1043176 N21DA206 1043177 N21DA193 1043869 N21KA137 1044737 N22IA172 1044800 N22IA130 I0550A Engine Model Engine Serial No. Crankshaft Serial No.

1043709 N22DA203 1043711 N22DA198 I0550B Engine Model Engine Serial No. Crankshaft Serial No.

1041409 N21BA147 1042310 N21JA118 1042374 N21JA154 1042518 N21JA141 1042618 N21JA157 1042619 N21JA052 1042671 N21FA231 1042672 N21FA233 1042712 N21JA053 I0520F Engine Model Engine Serial No. Crankshaft Serial No.

ISSUED REVISED DOC NO REVISION PAGE 2023/02/13 2023/02/16 MSB23-01 A 4 of 30 1043000 N22AA056 1043001 N22CA045 1043068 N21KA016 1043111 N22BA086 1043150 N22BA085 1043239 N22BA087 1043248 N22BA088 1043405 N22BA105 1043470 N22CA005 1043495 N22CA050 1043500 N22CA060 1043502 N22CA240 1043503 N22CA236 1043509 N22CA055 1043511 N22CA234 1043529 N22CA252 1043545 N22CA274 1043552 N22CA039 1043576 N22CA283 1043584 N22DA015 1043630 N22DA170 1043672 N22DA188 1043673 N22DA175 1043698 N22DA197 1043749 N22EA038 1043803 N22EA055 1043849 N22EA210 1043872 N22EA246 1043950 N22EA141 1043961 N22FA030 1043971 N22EA193 1043972 N22FA020 1043975 N22EA136 1044104 N22FA096 1044196 N22GA103 1044197 N22GA110 1044198 N22GA096 1044363 N22DA196 1044374 N22DA190 1044392 N22HA084 I0550B Engine Model Engine Serial No. Crankshaft Serial No.

1044401 N22HA176 1044449 N22FA028 1044471 N22HA117 1044473 N22CA279 1044481 N22HA132 1044486 N22HA077 1044490 N22FA005 1044495 N22HA067 1044496 N22HA104 1044497 N22HA069 1044501 N22BA092 1044511 N22HA116 1044516 N22FA081 1044572 N22HA159 1044576 N22IA056 1044579 N22IA028 1044690 N22JA038 1044723 N22JA079 1044741 N22JA107 1044760 N22KA176 1044761 N22JA026 1044900 N22KA133 I0550C Engine Model Engine Serial No. Crankshaft Serial No.

1041264 J229911N 1042691 N21JA168 1042692 N21JA051 1042693 N21JA189 1042694 N21JA190 1042992 N21KA022 1042996 N21KA028 1042997 N22AA103 1043116 N22AA028 1043117 N22AA025 1043178 N22BA107 1043179 N22BA109 1043180 N22BA089 1043195 N22BA104 I0550B Engine Model Engine Serial No. Crankshaft Serial No.