STANDARD PRACTICE

MAINTENANCE
MANUAL

SPARK IGNITED ENGINES

Technical Portions Accepted by the Federal Aviation Administration

Publication M-0, Revision 1  

©2019
CONTINENTAL MOTORS, INC. SEP 2019
 Supersedure Notice
This manual incorporates maintenance and service information contained in Continental Aerospace Technologies™
Service Documents common to the horizontally opposed, spark ignition, aviation gasoline (AvGas) engines
conforming to Type Certificate held by Continental Motors, Inc. This document is supplemental to the Instructions
for Continued Airworthiness provided in the manuals listed in Section 1-1.1. Instructions contained in the Service
Documents listed in Section 1-2.4 are superseded by instructions in this manual upon release, except for those
Mandatory Service Bulletins (MSBs) and Critical Service Bulletins (CSBs).

Effective Changes for this Manual

0 ............15 Sep 2019

List of Effective Pages

Document Title: Standard Practice Maintenance Manual
Publication Number: M-0 Initial Publication Date: 15 August 2019
Page Change Page Change Page Change Page Change
Cover............. Revision 1 B-1 thru B-16 ................0
A................................... 0 C-1 thru C-26................0
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Published and printed in the U.S.A. by Continental Motors, Inc. dba Continental Aerospace Technologies™

Available exclusively from the publisher: P.O. Box 90, Mobile, AL 36601
Copyright © 2019 Continental Motors, Inc. All rights reserved. This material may not be reprinted, republished, broadcast, or otherwise altered
without the publisher's written permission. This manual is provided without express, statutory, or implied warranties. The publisher will not be
held liable for any damages caused by or alleged to be caused by use, misuse, abuse, or misinterpretation of the contents. Content is subject to
change without notice. Other products and companies mentioned herein may be trademarks of the respective owners.

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 Preface
This manual was developed in accordance with Title 14, Code of Federal Regulations (CFR) Part
33, §33.4 as the Instructions for Continued Airworthiness (ICA) for Standard Practices.
Continental Motors, Inc. provides ICAs based on the design, testing, and certification of engines
and parts. Continental Motors, Inc. is the holder of the Type Certificate (TC) or Parts Manufacture
Approval (PMA) issued by the Federal Aviation Administration (FAA). Instructions in
Continental manuals, which include maintenance, repair limits, and overhaul instructions, are
applicable only to Continental Aerospace Technologies™ (Continental®) engines and parts.

Except for authorized owner preventive maintenance (defined in Title 14, Code of Federal
Regulations (CFR) Part 43 §§43.3 and 43.13), Continental ICAs are written for exclusive use by
FAA (or equivalent authority) licensed mechanics or FAA (or equivalent authority) certified
repair station employees.

Information and instructions contained in this manual anticipate the user possesses and applies the
knowledge, training, and experience commensurate with the requirements to meet the prerequisite
FAA license and/or certification requirements. No other use is authorized. It is the responsibility
of the owner to verify the mechanic or facility operating, maintaining, or servicing the engine uses
the most current ICA, including manual change pages, service documents, and FAA
Airworthiness Directives (ADs), to perform those functions.

Aftermarket parts installed on a Continental engine constitutes a deviation from type-design

criteria. Continental has not participated in design, test, or certification of any aftermarket parts.
Continental does not provide product manufacturing specifications to aftermarket parts
manufacturers and accepts no liability for the suitability, durability, longevity, or safety of such
parts installed on Continental engines. Installation of aftermarket parts on a Continental engine
must be performed using ICAs prepared by the manufacturer and found acceptable by the FAA
for the subject installation. Continental ICAs must not be used for such parts.
WARNING
Ensure you have the latest revision of this manual, any
applicable change pages, FAA Airworthiness Directives and
Continental service documents prior to commencing engine
service, inspection, maintenance, or overhaul.
To facilitate the use of current data, Continental provides the latest information on the Continental
web site (http://www.continental.aero). This information (applicable to current versions) includes
an index of manuals, links to active service documents, FAA Airworthiness Directives, and other
information applicable to the ICAs. Additionally, Continental technical publications (the current
version in electronic or printed format) are available through our publications distributor, Aircraft
Technical Publishers (ATP) (www.atp.com). Refer to “Related Publications” in Section 1-2.5. for
additional information about service subscriptions and ATP contact information (see Table 1-2).

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 Table of Contents
TABLE OF CONTENTS

Chapter 1. Introduction
1-1. Scope and Purpose of This Manual.............................................................................................. 1-1
1-1.1. Instructions for Continued Airworthiness........................................................................... 1-1
1-1.2. Advisories ........................................................................................................................... 1-3
1-1.3. Effectivity Symbols ............................................................................................................ 1-3
1-1.4. Using this Manual............................................................................................................... 1-4
1-1.5. Compliance ......................................................................................................................... 1-6
1-1.6. Order of Precedence ........................................................................................................... 1-7
1-2. Publications .................................................................................................................................. 1-7
1-2.1. Publication Access.............................................................................................................. 1-7
1-2.2. Publication Changes ........................................................................................................... 1-7
1-2.3. Update/Change Distribution ............................................................................................... 1-8
1-2.4. Service Documents ........................................................................................................... 1-10
1-2.4.1. Service Documents Incorporated in this Manual .................................................... 1-11
1-2.4.2. Service Documents Released After Publication ..................................................... 1-13
1-2.5. Related Publications ......................................................................................................... 1-15
1-2.5.1. Suggestions and Corrections ................................................................................... 1-15
1-3. Contact Information ................................................................................................................... 1-16
1-4. Service Parts............................................................................................................................... 1-16
1-4.1. Service Part Applicability and Availability....................................................................... 1-16
1-4.2. Part Supersedure ............................................................................................................... 1-16

Chapter 2. Tools
2-1. Special Tools ................................................................................................................................ 2-1
2-1.1. Vendor Contact Information ............................................................................................... 2-7
2-2. Mechanic’s Tools ....................................................................................................................... 2-23

Chapter 3. Lubricants, Sealants, and

Adhesives
3-1. Engine Oil Specifications............................................................................................................. 3-1
3-2. Oil Change Intervals .................................................................................................................... 3-3
3-3. Additives ...................................................................................................................................... 3-3
3-3.1. General Sealant Application Instructions ..........................................................................3-11
3-3.1.1. Four Cylinder Engine Crankcase Threading........................................................... 3-12
3-3.1.2. Six Cylinder Engine Crankcase Threading ............................................................. 3-14
3-3.2. Scavenge Pump Body Sealant and Threading .................................................................. 3-18
3-3.3. Oil Pump Assembly Sealant and Threading ..................................................................... 3-19
3-3.4. Starter Adapter Assembly Sealant and Threading ............................................................ 3-23
3-3.5. Starter Adapter Accessory Drive Cover Sealant and Threading....................................... 3-24

Chapter 4. Airworthiness Limitation Section

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Chapter 5.Engine Removal & Installation
5-1. Engine Removal ........................................................................................................................... 5-1
5-1.1. Tools and Consumable Supplies ......................................................................................... 5-1
5-1.2. Engine Removal Procedure ................................................................................................ 5-1
5-2. Engine Installation........................................................................................................................ 5-2
5-2.1. Common Tools and Consumable Supplies ......................................................................... 5-2
5-2.2. Engine Receipt and Handling ............................................................................................. 5-3
5-2.3. Uncrating the Engine .......................................................................................................... 5-3
5-2.4. Crating an Engine for Shipping .......................................................................................... 5-3
5-2.5. Acceptance Inspection ........................................................................................................ 5-3
5-2.6. Engine Transport................................................................................................................. 5-4
5-2.7. Engine Installation Procedures ........................................................................................... 5-4
5-2.8. Engine Adjustments and Component Replacement by OEMs and STC Converters.......... 5-5
5-2.9. Engine Pre-oiling ................................................................................................................ 5-7

Chapter 6. Engine Inspection and Service

6-1. Engine Inspection Introduction .................................................................................................... 6-1
6-2. Inspection and Maintenance Schedule ......................................................................................... 6-1
6-3. Time Between Overhaul ............................................................................................................... 6-1
6-4. Scheduled Inspections .................................................................................................................. 6-5
6-4.1. One Time Post - Installation Inspections ............................................................................ 6-6
6-4.2. 25-Hour Initial Operation Inspection.................................................................................. 6-6
6-4.3. 50-Hour Engine Inspection ................................................................................................. 6-8
6-4.4. 100-Hour (Annual) Engine Inspection ............................................................................... 6-9
6-4.5. 500-Hour Engine Inspection ............................................................................................. 6-11
6-4.6. Visual Inspection............................................................................................................... 6-12
6-4.7. Engine Operational Check ................................................................................................ 6-14
6-4.7.1. Fuel Injection System Specifications ...................................................................... 6-15
6-4.7.2. Maintenance Preflight Inspection............................................................................ 6-20
6-4.7.3. Oil Pump Operational Check .................................................................................. 6-22
6-4.7.4. Fuel System Operational Check .............................................................................. 6-23
6-4.7.5. Magneto RPM Drop Check..................................................................................... 6-31
6-4.7.6. Engine Shutdown .................................................................................................... 6-32
6-4.8. Engine Oil Servicing......................................................................................................... 6-33
6-4.8.1. Check and Replenish Engine Oil Level .................................................................. 6-33
6-4.8.2. Oil Change............................................................................................................... 6-49
6-4.8.3. Check for Oil Leaks ................................................................................................ 6-52
6-4.8.4. Oil Sample Collection ............................................................................................. 6-52
6-4.8.5. Oil Trend Monitoring and Spectrographic Oil Analysis ......................................... 6-53
6-4.9. Ignition System Maintenance ........................................................................................... 6-54
6-4.9.1. Ignition Timing ....................................................................................................... 6-54
6-4.9.2. Spark Plug Maintenance.......................................................................................... 6-62
6-4.9.3. Ignition Harness Maintenance................................................................................. 6-66
6-4.10. Engine Adjustments ........................................................................................................ 6-68
6-4.10.1. Oil Pressure Adjustment........................................................................................ 6-68
6-4.10.2. Fuel System Adjustment ....................................................................................... 6-70
6-4.10.3. Manifold Pressure Adjustment.............................................................................. 6-91
6-4.10.4. Belt Tension Check and Adjustment..................................................................... 6-96

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6-4.11. Cylinder Inspections ..................................................................................................... 6-102
6-4.11.1. Cylinder Visual Inspection.................................................................................. 6-103
6-4.11.2. Differential Pressure Test.................................................................................... 6-105
6-4.11.3. Cylinder Borescope Inspection ........................................................................... 6-113
6-4.11.4. Cylinder to Crankcase Mounting Deck Inspection ............................................. 6-117
6-4.11.5. Baffle Inspection ................................................................................................. 6-118
6-4.11.6. Cowling Inspection ............................................................................................. 6-122
6-4.12. Crankcase Inspection .................................................................................................... 6-122
6-4.12.1. Crankcase Critical Stress Areas .......................................................................... 6-125
6-4.13. Engine Mount Inspection.............................................................................................. 6-129
6-4.14. Induction System Inspection ........................................................................................ 6-129
6-4.15. Ignition System Inspection ........................................................................................... 6-131
6-4.15.1. Impulse Coupling Functional Check................................................................... 6-133
6-4.15.2. Starting Vibrator Functional Check .................................................................... 6-134
6-4.15.3. Magneto Drive Coupling Inspection................................................................... 6-134
6-4.16. Engine Gauge Inspection.............................................................................................. 6-135
6-4.17. Fuel System Inspection................................................................................................. 6-136
6-4.18. Throttle and Mixture Control Lever Inspection............................................................ 6-137
6-4.19. Engine Control Linkage Inspection .............................................................................. 6-139
6-4.20. Induction System Drain Inspection .............................................................................. 6-141
6-4.20.1. Induction System Drain Inspection (Naturally Aspirated Engines).................... 6-142
6-4.20.2. Induction System Drain Inspection (Turbocharged Engines)............................. 6-143
6-4.21. Turbocharger and Exhaust System Inspection.............................................................. 6-144
6-4.21.1. Turbocharger Oil Supply Check Valve Inspection ............................................. 6-149
6-4.22. Alternator Inspection .................................................................................................... 6-153
6-4.22.1. Alternator Drive Coupling Inspection ................................................................ 6-154
6-4.22.2. Alternator Drive Coupling Inspection ................................................................ 6-155
6-5. Unscheduled Maintenance ....................................................................................................... 6-158
6-5.1. Propeller Strike ............................................................................................................... 6-158
6-5.1.1. Propeller Strike Inspection.................................................................................... 6-158
6-5.2. Hydraulic Lock Inspection ............................................................................................. 6-159
6-5.3. Engine Overspeed Inspections........................................................................................ 6-160
6-5.3.1. Category I Overspeed Inspection .......................................................................... 6-161
6-5.3.2. Category II Overspeed Inspection......................................................................... 6-161
6-5.3.3. Category III Overspeed Inspection ....................................................................... 6-162
6-5.4. Turbocharger Overboost ................................................................................................. 6-162
6-5.5. Lightning Strike Inspection ............................................................................................ 6-162
6-5.6. Contaminated Fuel System Inspection ........................................................................... 6-163
6-5.7. Foreign Object Contamination Inspection...................................................................... 6-163
6-5.8. Sticking or Stuck Valves................................................................................................. 6-164
6-6. Inspection Checklists ............................................................................................................... 6-166

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Chapter 7. Engine Operation
7-1. Introduction .................................................................................................................................. 7-1
7-2. Flight Prerequisites....................................................................................................................... 7-1
7-2.1. Oil Change Interval............................................................................................................. 7-1
7-2.2. Engine Fuel Requirements.................................................................................................. 7-2
7-2.3. Engine Operation after Cylinder Replacement and/or Major Overhaul ............................. 7-6
7-2.4. Flight Check and Break-In.................................................................................................. 7-8
7-2.4.1. Engine Break-In ........................................................................................................ 7-8
7-2.4.2. Flight Check .............................................................................................................. 7-9
7-3. Normal Operation....................................................................................................................... 7-18
7-3.1. Pre-operational Requirements........................................................................................... 7-18
7-3.2. Engine Start....................................................................................................................... 7-19
7-3.2.1. Cold Start................................................................................................................. 7-20
7-3.2.2. Flooded Engine ....................................................................................................... 7-20
7-3.2.3. Hot Start .................................................................................................................. 7-21
7-3.3. Ground Run-up ................................................................................................................. 7-22
7-3.4. Engine Shutdown .............................................................................................................. 7-24
7-4. Engine Operation in Abnormal Environments ........................................................................... 7-25
7-4.1. Engine Operation in Extreme Cold................................................................................... 7-25
7-4.1.1. Engine Preheating ................................................................................................... 7-26

Chapter 8. Troubleshooting
8-1. General Troubleshooting .............................................................................................................. 8-2
8-1.1. General Troubleshooting for Engines equipped with a Carburetor .................................... 8-2
8-1.2. General Troubleshooting for Engines with Continuous Flow Fuel Injection Systems....... 8-3
8-1.3. Engine Runs Rough ............................................................................................................ 8-4
8-1.3.1. Engine Runs Rough (equipped with Carburetor) ...................................................... 8-4
8-1.3.2. Engine Runs Rough (equipped with Continuous Flow Fuel Injection System) ....... 8-5
8-1.4. Engine Will Not Run........................................................................................................... 8-6
8-1.5. Engine Indication Malfunctions.......................................................................................... 8-7
8-1.6. Engine Performance Malfunctions ..................................................................................... 8-8
8-2. Induction System .......................................................................................................................... 8-9
8-2.1. Engine Will Not Start.......................................................................................................... 8-9
8-2.2. Engine Will Not Run......................................................................................................... 8-10
8-2.3. Engine Lacks Power/Manifold Pressure Low (Naturally Aspirated Models) .................. 8-10
8-2.4. Engine Lacks Power/Manifold Pressure Low (Turbocharged Models)............................ 8-11
8-3. Continental Continuous Flow Fuel Injection System................................................................. 8-12
8-3.1. Engine Will Not Start........................................................................................................ 8-12
8-3.2. Fluctuating or Erroneous Fuel Flow ................................................................................. 8-13
8-3.3. Poor Acceleration.............................................................................................................. 8-13
8-3.4. Fuel Injector Operational Check....................................................................................... 8-14
8-4. Charging System ........................................................................................................................ 8-16
8-5. Starting System........................................................................................................................... 8-16
8-6. Ignition System........................................................................................................................... 8-17
8-6.1. Ignition Harness and Spark Plug Diagnostics................................................................... 8-18
8-7. Lubrication System..................................................................................................................... 8-19
8-8. Engine Cylinders ........................................................................................................................ 8-21
8-9. Crankcase ................................................................................................................................... 8-23
8-9.1. Excess Crankcase Pressure ............................................................................................... 8-24
8-10. Turbocharger and Exhaust System ........................................................................................... 8-25

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Chapter 9. Engine Preservation and Storage
9-1. Preserving and Storing an Engine ................................................................................................ 9-1
9-1.1. Engine Preservation Checklist............................................................................................ 9-1
9-1.2. New or Unused Engine Storage.......................................................................................... 9-1
9-1.3. Installed Engine, Temporary Storage ................................................................................. 9-1
9-1.4. Installed Engine, Indefinite Storage ................................................................................... 9-3
9-1.5. Crated Engine, Indefinite Storage ...................................................................................... 9-4
9-1.6. Return an Engine to Service after Storage.......................................................................... 9-6

Chapter 10.Non-Overhaul Repair and

Replacement
10-1. Parts Replacement.................................................................................................................... 10-1
10-2. Fuel Injector Replacement ....................................................................................................... 10-3
10-2.1. Nozzle Identification ...................................................................................................... 10-3
10-2.2. Fuel Injector Removal (Turbocharged Engines) ............................................................ 10-4
10-2.3. Fuel Injector Installation (Turbocharged Engines)......................................................... 10-4
10-2.4. Fuel Injector Removal (Naturally Aspirated Engines) ................................................... 10-6
10-2.5. Fuel Injector Installation (Naturally Aspirated Engines)................................................ 10-6
10-3. Induction Drain Connector Replacement................................................................................. 10-8
10-3.1. Induction Drain Connector Removal and Cleaning ....................................................... 10-8
10-3.2. Induction Drain Connector Installation .......................................................................... 10-8
10-4. Alternator Replacement............................................................................................................ 10-9
10-4.1. Gear Driven Alternator Replacement, Forward Mount ................................................ 10-9
10-4.1.1. Gear Driven Alternator Removal ......................................................................... 10-9
10-4.1.2. Alternator Drive Coupling Removal .................................................................. 10-11
10-4.1.3. Alternator Drive Coupling Installation .............................................................. 10-11
10-4.1.4. Alternator Drive Coupling Slippage Inspection ................................................. 10-12
10-4.1.5. Gear Driven Alternator Installation ................................................................... 10-13
10-4.2. Gear Driven Alternator Replacement, Aft Mount ....................................................... 10-14
10-4.2.1. Gear Driven Alternator Removal ....................................................................... 10-14
10-4.2.2. Alternator Drive Hub Removal .......................................................................... 10-16
10-4.2.3. Alternator Drive Hub Installation ...................................................................... 10-16
10-4.2.4. Gear Driven Alternator Installation ................................................................... 10-18
10-4.3. Alternator Service Instructions ..................................................................................... 10-19
10-5. Magneto Replacement............................................................................................................ 10-21
10-5.1. Continental Magneto Removal..................................................................................... 10-21
10-5.2. Continental Magneto Installation ................................................................................. 10-22
10-5.3. Champion (Slick) Magneto Removal ........................................................................... 10-24
10-5.4. Champion (Slick) Magneto Installation ....................................................................... 10-25
10-5.5. Magneto Filter Replacement ........................................................................................ 10-27
10-5.5.1. Continental Magneto Filter Replacement ........................................................... 10-27
10-5.5.2. Champion (Slick) Magneto Filter Replacement ................................................. 10-29
10-6. Cylinder Repairs..................................................................................................................... 10-31
10-6.1. Cylinder Replacement .................................................................................................. 10-32
10-6.1.1. Cylinder Removal ............................................................................................... 10-32
10-6.1.2. Cylinder Installation............................................................................................ 10-34
10-6.1.3. Cylinder Torque .................................................................................................. 10-37
10-6.2. Cylinder Position Numbers .......................................................................................... 10-38
10-6.3. Cylinder Head Repair ................................................................................................... 10-38

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10-6.4. Cylinder Fin Tip Repair ................................................................................................ 10-39
10-6.5. Cylinder Bore Inspection .............................................................................................. 10-39
10-6.6. Cylinder Barrel Repair.................................................................................................. 10-39
10-6.7. Cylinder Bore Honing................................................................................................... 10-40
10-6.8. Cylinder Stud Replacement .......................................................................................... 10-41
10-6.9. Spark Plug Heli-coil Replacement................................................................................ 10-42
10-6.10. Cylinder Protective Coatings ...................................................................................... 10-43
10-6.11. Cylinder Bore and Piston Fit Specifications ............................................................... 10-44
10-6.12. Legacy Product Replacement Valves.......................................................................... 10-53
10-7. Crankcase Repair.................................................................................................................... 10-56
10-8. Piston Replacement ................................................................................................................ 10-56
10-9. Crankshaft Repair................................................................................................................... 10-57
10-9.1. Crankshaft Counterweight Inspection and Repair ........................................................ 10-57
10-9.1.1. Crankshaft Counterweight Removal ................................................................... 10-76
10-9.1.2. Counterweight Identification............................................................................... 10-77
10-9.1.3. Crankshaft Counterweight Inspection ................................................................. 10-82
10-9.1.4. Crankshaft Counterweight Bushing Bore Inspection.......................................... 10-83
10-9.1.5. Crankshaft Counterweight Bushing Replacement .............................................. 10-85
10-9.1.6. Crankshaft Hanger Blade Bushing Inspection .................................................... 10-88
10-9.2. Oil Control Plug Replacement ...................................................................................... 10-90
10-9.3. Crankshaft Plating Overhaul......................................................................................... 10-92
10-9.4. Connecting Rod Replacement ...................................................................................... 10-93
10-9.4.1. Connecting Rod Dimensional Inspection............................................................ 10-93
10-9.4.2. Connecting Rod Piston Pin Bushing Replacement ............................................. 10-98
10-9.4.3. Connecting Rod Piston Pin Bushing Boring ..................................................... 10-100
10-10. Crankshaft Nose Oil Seal Replacement ............................................................................. 10-101
10-10.1. Solid Nose Oil Seal Removal ................................................................................... 10-101
10-10.2. Solid Nose Oil Seal Installation................................................................................ 10-102
10-10.3. Split Nose Oil Seal Removal .................................................................................... 10-104
10-10.4. Split Type Nose Oil Seal Installation........................................................................ 10-104
10-11. Exhaust Flange to Cylinder Installation ............................................................................. 10-106

Chapter 11. Non-Destructive Inspection

11-1. Visual Inspection ...................................................................................................................... 11-1
11-1.1. Gear Tooth Inspection ..................................................................................................... 11-2
11-2. Fluorescent Penetrant Inspection.............................................................................................. 11-3
11-3. Magnetic Particle Inspection .................................................................................................... 11-4
11-3.1. Connecting Rod Magnetic Particle Inspection................................................................ 11-6
11-4. Ultrasonic Inspection................................................................................................................ 11-7
11-4.1. Ultrasonic Inspection Certification ................................................................................. 11-7
11-4.2. Crankshaft Ultrasonic Inspection.................................................................................... 11-8

Chapter 12. Engine Cleaning

12-1. Engine and Component Cleaning............................................................................................. 12-1
12-1.1. Cylinder Cleaning ........................................................................................................... 12-6
12-1.2. Piston Cleaning ............................................................................................................... 12-7
12-1.3. Cleaning Exhaust Parts ................................................................................................... 12-8
12-1.4. Cleaning Aluminum Alloy Parts ..................................................................................... 12-8
12-2. Dry Blasting ............................................................................................................................. 12-9

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12-3. Vapor Blasting .......................................................................................................................... 12-9
12-4. Protective Coatings ................................................................................................................ 12-10
12-4.1. Alodine.......................................................................................................................... 12-10
12-4.2. Aviation Oil................................................................................................................... 12-10
12-4.3. Paint ...............................................................................................................................12-11

Appendix A.Glossary
A-1. Acronyms ....................................................................................................................................A-1
A-2. Terms and Definitions .................................................................................................................A-3

Appendix B.Torque Specifications

B-1. General Information ....................................................................................................................B-1
B-1.1. Torque Tips ........................................................................................................................B-2
B-2. Part Supersedure..........................................................................................................................B-3
B-3. Torque Wrench and Extension Calculations................................................................................B-4

Appendix C.Maintenance Standards

C-1. Handling Parts .............................................................................................................................C-1
C-2. Replacement Parts .......................................................................................................................C-3
C-2.1. Background ........................................................................................................................C-3
C-2.2. Acceptable Replacement Parts...........................................................................................C-3
C-2.2.1. Know Your Supplier ................................................................................................C-3
C-2.3. 100% Parts Replacement Requirements ............................................................................C-4
C-2.4. Mandatory Overhaul Replacement Parts ...........................................................................C-5
C-2.5. Authorized Oversize/Undersize Parts ................................................................................C-8
C-2.6. Special Instructions............................................................................................................C-8
C-2.7. Engine Data Plate Replacement.........................................................................................C-8
C-2.7.1. Removal and Installation of Engine Data Plate........................................................C-8
C-3. Safety Wiring Hardware ............................................................................................................C-10
C-4. Tab Washer Installation .............................................................................................................C-12
C-5. Heli-Coil® Insert Replacement .................................................................................................C-13
C-5.1. Heli-Coil Removal ...........................................................................................................C-14
C-5.2. Heli-Coil Insertion ...........................................................................................................C-15
C-6. Stud Replacement......................................................................................................................C-16
C-6.1. Stud Removal...................................................................................................................C-16
C-6.1.1. Size-on-Size Rosan® Stud Removal......................................................................C-16
C-6.1.2. Step-Type Rosan® Stud Removal..........................................................................C-17
C-6.2. Stud Installation ...............................................................................................................C-18
C-6.2.1. Rosan® Stud Installation........................................................................................C-19
C-7. Cotter Pin Installation................................................................................................................C-20
C-8. Fuel System Service ..................................................................................................................C-21
C-8.1. Fuel System Purge ...........................................................................................................C-21
C-9. Gasket Maker® Application......................................................................................................C-22
C-10. Gasket Installation ...................................................................................................................C-23
C-10.1. Crush Washer Installation ..............................................................................................C-23
C-11. Hose and Tubing Installation ...................................................................................................C-24
C-12. Harness Routing ......................................................................................................................C-25

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LIST OF TABLES

Table 1-1. Service Documents Incorporated in Manual ..............................................1-11

Table 1-2. Related Publications ...................................................................................1-15

Table 2-1. Special Tools List .........................................................................................2-1

Table 2-2. Tools, Accessories, and Supply Vendors .....................................................2-7
Table 2-3. Common Tools ...........................................................................................2-24

Table 3-1. Qualified SAE J1899 Ashless Dispersant Engine Oil ..................................3-2
Table 3-2. Qualified SAE J1966 Non-Dispersant Mineral Oil ......................................3-2
Table 3-3. Break-in Oil ..................................................................................................3-2
Table 3-4. Preservative Oil ............................................................................................3-2
Table 3-5. Sealants .........................................................................................................3-4
Table 3-6. Lubricants .....................................................................................................3-5
Table 3-7. Adhesives .....................................................................................................3-8
Table 3-8. Miscellaneous ...............................................................................................3-9

Table 5-1. Authorized Adjustments and Replacements .................................................5-6

Table 6-1. Engine Time Between Overhaul (TBO) .......................................................6-3

Table 6-2. Engine Inspection and Maintenance Schedule .............................................6-5
Table 6-3. Engine Operation Prerequisites ..................................................................6-14
Table 6-4. Fuel System Adjustment Values ................................................................6-15
Table 6-5. Static Ground Setup Compensation Table .................................................6-19
Table 6-6. IO-240-A, B With Standard Fuel Pump .....................................................6-20
Table 6-7. Magneto Timing Specifications - Geared Engines .....................................6-54
Table 6-8. Magneto Timing Specifications - Direct Drive Engines ............................6-54
Table 6-9. Spark Plug Application Chart .....................................................................6-63
Table 6-10. Spark Plug Rotation Chart ..........................................................................6-65
Table 6-11. IO-360-D/DB Engine Altitude Leaning Schedule .....................................6-84
Table 6-12. IO-360-ES Engine Altitude Leaning Schedule ..........................................6-85
Table 6-13. IO-360-ES (Cirrus SR20) Engine Altitude Leaning Schedule ...................6-86
Table 6-14. IO-550-A Engine Altitude Leaning Schedule ............................................6-87
Table 6-15. IO-550-B Engine Altitude Leaning Schedule ............................................6-88
Table 6-16. IO-550-C Engine Altitude Leaning Schedule ............................................6-89
Table 6-17. IO-550-D, E, F, & L Engine Altitude Leaning Schedule ...........................6-90
Table 6-18. VAPC Parameters .......................................................................................6-95
Table 6-19. Cylinder Inspection Tasks and References ...............................................6-102
Table 6-20. Additional Cylinder Service Document References .................................6-102
Table 6-21. Differential Pressure Test Results ............................................................6-111
Table 6-22. Borescope Inspection Objectives and Corrective Actions .......................6-114
Table 6-23. Crankcase Casting Numbers .....................................................................6-122
Table 6-24. Exhaust Inspection Criteria ......................................................................6-144
Table 6-25. Overspeed Categories ...............................................................................6-160
Table 6-26. Engine Operational Checklist ...................................................................6-167

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Table 6-27. 25-Hour Initial Operation Inspection Checklist .......................................6-169
Table 6-28. 50-Hour Engine Inspection Checklist ......................................................6-171
Table 6-29. 100-Hour Engine Inspection Checklist ....................................................6-173
Table 6-30. 500-Hour Engine Inspection Checklist ....................................................6-175
Table 6-31. Cylinder Inspection Checklist ..................................................................6-177

Table 7-1. Aviation Fuel Specifications ........................................................................7-3

Table 7-2. Authorized Fuels by Engine Model .............................................................7-3
Table 7-3. IO-360-D/DB Engine Altitude Leaning Schedule .....................................7-11
Table 7-4. IO-360-ES Engine Altitude Leaning Schedule ..........................................7-12
Table 7-5. IO-360-ES (Cirrus SR20) Engine Altitude Leaning Schedule ...................7-13
Table 7-6. IO-550-A Engine Altitude Leaning Schedule ............................................7-14
Table 7-7. IO-550-B Engine Altitude Leaning Schedule ............................................7-15
Table 7-8. IO-550-C Engine Altitude Leaning Schedule ............................................7-16
Table 7-9. IO-550-D, E, F, & L Engine Altitude Leaning Schedule ...........................7-17

Table 9-1. Engine Preservation Checklist .....................................................................9-7

Table 10-1. Non-Overhaul Parts Replacement Reference .............................................10-1

Table 10-2. Parts Repair Reference ...............................................................................10-2
Table 10-3. Parts Handling Guidelines ..........................................................................10-2
Table 10-4. Alternator Drive Coupling Slippage ........................................................10-12
Table 10-5. Alternator Cross Reference ......................................................................10-20
Table 10-6. Cylinder Repair vs. Replacement Guidelines ..........................................10-31
Table 10-7. Cylinder Bore Surface Finish Specifications ...........................................10-41
Table 10-8. 5.250 Inch Cylinder Barrel Dimensions ...................................................10-45
Table 10-9. 5.250 Inch Cylinder Barrel Dimensions ...................................................10-46
Table 10-10. 5.250 Inch Piston to Cylinder Clearance ..................................................10-46
Table 10-11. 5.250 Inch Piston to Cylinder Clearance ..................................................10-46
Table 10-12. 5.250 Inch Piston to Cylinder Clearance ..................................................10-46
Table 10-13. 5.000 Inch Cylinder Barrel Dimensions ...................................................10-47
Table 10-14. 5.000 Inch Piston to Cylinder Clearance ..................................................10-47
Table 10-15. 5.000 Inch Piston to Cylinder Clearance ..................................................10-47
Table 10-16. 4.438 Inch Cylinder Barrel Dimensions ...................................................10-48
Table 10-17. 4.438 Inch Piston to Cylinder Clearance ..................................................10-48
Table 10-18. 4.062 Inch Cylinder Barrel Dimensions ...................................................10-49
Table 10-19. 4.062 Inch Piston to Cylinder Clearance ..................................................10-49
Table 10-20. Ring Gap Specifications ...........................................................................10-50
Table 10-21. Ring Gap Specifications ...........................................................................10-51
Table 10-22. Ring Gap Specifications ...........................................................................10-51
Table 10-23. Ring Gap Specifications ...........................................................................10-51
Table 10-24. Ring Gap Specifications ...........................................................................10-51
Table 10-25. Engine to Piston Cross Reference ............................................................10-52
Table 10-26. Engines Serial Number Applicability ......................................................10-53
Table 10-27. Replacement Components for Low Compression Ratio Cylinders .........10-54
Table 10-28. Cylinder Part Number Conversion ...........................................................10-54

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Table 10-29. Engine Power Train ..................................................................................10-58
Table 10-30. Crankshaft Assembly Part Number History .............................................10-65
Table 10-31. Crankshaft Assemblies .............................................................................10-70
Table 10-32. Crankshaft Hanger Blade Bushing Sizes ..................................................10-73
Table 10-33. Wide Rod Crankshaft ...............................................................................10-74
Table 10-34. Counterweight Supersedure ......................................................................10-76
Table 10-35. Counterweight Bushing Bore Dimensions ...............................................10-84
Table 10-36. Counterweight Bushing Bore Dimensions ...............................................10-87
Table 10-37. Counterweight Hanger Blade Bushing Dimensions .................................10-89
Table 10-38. Crankshaft Oil Plug Installation Specifications .......................................10-90
Table 10-39. Connecting Rod Specifications ................................................................10-96
Table 10-40. Exhaust Gaskets, Nuts, and Nut Torque Values .....................................10-107

Table 11-1. Parts Requiring Fluorescent Penetrant Inspection ......................................11-3

Table 11-2. Magnetic Particle Inspection Reference .....................................................11-5
Table 11-3. Connecting Rod Magnetic Particle Inspection Criteria ..............................11-6
Table 11-4. Crankshaft Ultrasonic Inspection Pass/Fail Action ....................................11-8

Table 12-1. Aircraft Engine Parts Cleaning Guidelines ................................................12-2

Table 12-2. Cleaning Tips ..............................................................................................12-5
Table 12-3. Painting External Parts .............................................................................12-11

Table B-1. Appendix B, Quick Table Reference ........................................................... B-1

Table B-2. Component Specific Torque Specifications ................................................ B-6
Table B-3. Specific Torque Specifications (Non-Lubricated Hardware) .................... B-13
Table B-4. FADEC Components (Non-Lubricated Hardware) ................................... B-13
Table B-5. General Torque Specifications .................................................................. B-14
Table B-6. Hydraulic Line Torque Specifications ....................................................... B-14
Table B-7. Straight Thread Fitting Torque Specifications .......................................... B-15
Table B-8. Hose Fitting (“B” Nut) Torque Specifications .......................................... B-15

Table C-1. Mandatory Overhaul Replacement Parts ..................................................... C-5

Table C-2. Rosan® Stud Primary & Secondary Bore Specifications ......................... C-17

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LIST OF FIGURES

Figure 1-1. Figure and Index Reference ..........................................................................1-5

Figure 1-2. Change Page Identification ...........................................................................1-8
Figure 1-3. List of Effective Pages ..................................................................................1-9

Figure 2-1. Model E2M Differential Pressure Tester (built in Master Orifice Tool) .....2-9
Figure 2-2. Borescope (Autoscope®) .............................................................................2-9
Figure 2-3. Pulley Alignment Tool ...............................................................................2-10
Figure 2-4. Porta-Test Model 20 ATM-C .....................................................................2-10
Figure 2-5. Gear Driven Alternator Drive Hub Torque Tool ........................................2-11
Figure 2-6. Alternator Drive Hub Torque Tool .............................................................2-12
Figure 2-7. Worm Shaft Tool and Starter Adapter Disassembly Tool ..........................2-12
Figure 2-8. Oil Control Plug Installation Tool - 360 Engines .......................................2-13
Figure 2-9. Oil Control Plug Installation Tool - 470 Engines .......................................2-13
Figure 2-10. Oil Control Plug Installation Tool - 520/550 Permold Engines .................2-14
Figure 2-11. Oil Control Plug Installation Tool - 470/520/550 Sandcast Engines .........2-14
Figure 2-12. Oil Control Plug Leak Test Fixture ............................................................2-15
Figure 2-13. Needle Bearing Installation Tool - Part 1 ...................................................2-16
Figure 2-14. Needle Bearing Installation Tool - Part 2 ...................................................2-17
Figure 2-15. Bearing Installation Tool ............................................................................2-18
Figure 2-16. Crankcase Needle Bearing Installation Tool, Permold ..............................2-19
Figure 2-17. Crankcase Needle Bearing Installation Tool, Sandcast ..............................2-19
Figure 2-18. Valve Guide Seal Installation Tool ............................................................2-20
Figure 2-19. O-Ring Installation Tool .............................................................................2-21
Figure 2-20. Oil Seal Tool ...............................................................................................2-21
Figure 2-21. Helical Coil Extraction Tool ......................................................................2-22
Figure 2-22. Helical Coil Insertion Tool .........................................................................2-22
Figure 2-23. Helical Coil Expanding Tool ......................................................................2-23
Figure 2-24. Rosan® Stud Removal Tool .......................................................................2-23

Figure 3-1. Anti-Seize Lubricant Application ...............................................................3-11

Figure 3-2. Fuel Injection Sealant Application .............................................................3-11
Figure 3-3. Crankcase Threading Diagram - C75, C85, C90, O200 .............................3-13
Figure 3-4. Crankcase Threading Diagram - O240, IO240, IOF240 ............................3-13
Figure 3-5. Crankcase Threading Diagram - O300 .......................................................3-15
Figure 3-6. Crankcase Threading Diagram - IO360, L/TSIO360 .................................3-15
Figure 3-7. Crankcase Threading Diagram - 520/550 Permold ....................................3-16
Figure 3-8. Crankcase Threading Diagram - 470/520/550 Sandcast ............................3-16
Figure 3-9. Crankcase Threading Diagram - GTSIO520 ..............................................3-17
Figure 3-10. Scavenge Pump Body Threading Diagram ................................................3-18
Figure 3-11. Oil Pump Assembly Threading Diagram ...................................................3-19
Figure 3-12. Oil Pump Assembly Threading Diagram ...................................................3-20
Figure 3-13. Oil Pump Assembly Threading Diagram ...................................................3-21
Figure 3-14. Oil Pump Assembly Threading Diagram ...................................................3-22
Figure 3-15. Oil Pump Assembly Threading Diagram ...................................................3-22
Figure 3-16. Starter Adapter Assembly Threading Diagram ..........................................3-23
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Figure 3-17. Accessory Drive Cover Threading Diagram ..............................................3-24

Figure 6-1. Part No. MS51523-B4 Swivel Tee .............................................................6-25

Figure 6-2. Porta-Test Model 20 ATM-C .....................................................................6-26
Figure 6-3. Typical Naturally Aspirated Fuel System Schematic ................................6-27
Figure 6-4. Typical Naturally Aspirated Fuel System Schematic ................................6-27
Figure 6-5. Typical Turbocharged Fuel System Schematic ..........................................6-28
Figure 6-6. Typical Turbocharged Fuel System Schematic ..........................................6-28
Figure 6-7. C-75, C-85, C-90 & O-200-A Oil Servicing Points, typical ......................6-34
Figure 6-8. O-200-D & X Oil Servicing Points, typical ...............................................6-34
Figure 6-9. IO-240-B Oil Servicing Points, typical ......................................................6-35
Figure 6-10. IO-360 Oil Servicing Points, typical ..........................................................6-36
Figure 6-11. IO-360-AF/ES Oil Servicing Points, typical ..............................................6-37
Figure 6-12. TSIO-360 Oil Servicing Points, typical .....................................................6-38
Figure 6-13. O-470 Oil Servicing Points, typical ...........................................................6-39
Figure 6-14. IO-470/TSIO-470 Oil Servicing Points, typical .........................................6-40
Figure 6-15. GTSIO-520 Oil Servicing Points, typical ..................................................6-41
Figure 6-16. IO-550-A, B & C Oil Servicing Points, typical .........................................6-42
Figure 6-17. IO-550-D, E & F Oil Servicing Points, typical ..........................................6-43
Figure 6-18. IO-550-G & N Oil Servicing Points, typical ..............................................6-44
Figure 6-19. IO-550-L Oil Servicing Points, typical ......................................................6-45
Figure 6-20. IO-550-P Oil Servicing Points, typical ......................................................6-46
Figure 6-21. IO-550-R Oil Servicing Points, typical ......................................................6-47
Figure 6-22. TSIO-550 Oil Servicing Points, typical .....................................................6-48
Figure 6-23. Disposable Oil Filter and Integral Screen ..................................................6-49
Figure 6-24. Oil Filter with Anti-Stick Gasket Label, typical ........................................6-51
Figure 6-25. O-200 28° BTC Timing .............................................................................6-56
Figure 6-26. O-200 24° BTC Timing .............................................................................6-56
Figure 6-27. Timing Disk and TDC Locator Installed ....................................................6-57
Figure 6-28. No. 1 Cylinder Positioned at Top of Intake Stroke ....................................6-58
Figure 6-29. Crankshaft Positioned at TDC ....................................................................6-58
Figure 6-30. Cylinder No. 1 Top of Compression Stroke ...............................................6-59
Figure 6-31. No. 1 Cylinder Full Advance Firing Position ............................................6-60
Figure 6-32. Spark Plug Inspection Criteria ...................................................................6-62
Figure 6-33. Lubricate Ignition Wire with MS-122AD ..................................................6-66
Figure 6-34. Elbow Kit Assembly ..................................................................................6-67
Figure 6-35. Oil Pressure Relief Valve Adjustment Screw Locations ...........................6-69
Figure 6-36. Fuel Pump, Naturally Aspirated Engine without Integral Mixture Control ... 6-72
Figure 6-37. Fuel Pump, Naturally Aspirated Engine with Integral Mixture Control ....6-72
Figure 6-38. Throttle and Metering Assembly ................................................................6-73
Figure 6-39. Throttle and Control Assembly, Front View ..............................................6-73
Figure 6-40. Throttle and Control Assembly, Side View ...............................................6-74
Figure 6-41. Altitude Compensating Fuel Pump (Auto-Lean), ......................................6-77
Naturally Aspirated Engine (without adjustable orifice)
Figure 6-42. Altitude Compensating Fuel Pump (Auto-Lean), ......................................6-77
Naturally Aspirated Engine (with adjustable orifice)
Figure 6-43. Aneroid Equipped Fuel Pump, Turbocharged Engine ...............................6-78
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Figure 6-44. Aneroid and Mixture Control Equipped Fuel Pump, .................................6-78
Turbocharged Engine
Figure 6-45. Fuel Pressure Regulator, Turbocharged Engine .........................................6-80
Figure 6-46. Altitude Leaning Schedule Adjustment Example ......................................6-82
Figure 6-47. Altitude Leaning after Correction ..............................................................6-83
Figure 6-48. IO-360-D/DB Altitude Leaning Schedule ..................................................6-84
Figure 6-49. IO-360-ES Altitude Leaning Schedule .......................................................6-85
Figure 6-50. IO-360-ES in Cirrus SR20 Altitude Leaning Schedule ..............................6-86
Figure 6-51. IO-550-A Altitude Leaning Schedule ........................................................6-87
Figure 6-52. IO-550-B Altitude Leaning Schedule .........................................................6-88
Figure 6-53. IO-550-C Altitude Leaning Schedule .........................................................6-89
Figure 6-54. IO-55-D, E, F & L Altitude Leaning Schedule ..........................................6-90
Figure 6-55. Fixed Wastegate, typical ............................................................................6-92
Figure 6-56. Fixed Wastegate (TSIO-520-T), typical .....................................................6-93
Figure 6-57. Sloped Controller, typical ...........................................................................6-94
Figure 6-58. Variable Absolute Pressure Controller .......................................................6-95
Figure 6-59. Air Conditioning Compressor Belt Tensioning ..........................................6-96
Figure 6-60. Optional Compressor Belt Tensioning, typical ..........................................6-97
Figure 6-61. Alternator Belt Tensioning .........................................................................6-98
Figure 6-62. 85 Amp Alternator Belt Adjustment ..........................................................6-99
Figure 6-63. Front Mount Belt Driven Alternator .........................................................6-100
Figure 6-64. Aft Mounted Alternator Belt Tension Adjustment ...................................6-101
Figure 6-65. Cylinder Power Stroke Areas ...................................................................6-103
Figure 6-66. Model E2M Differential Pressure Tester .................................................6-107
Figure 6-67. Differential Pressure Test Equipment Usage ...........................................6-109
Figure 6-68. Normal Combustion Chamber ..................................................................6-115
Figure 6-69. Burned Exhaust Valve ..............................................................................6-115
Figure 6-70. Phosphate-Coated Cylinder with Revised Hone Pattern ..........................6-115
Figure 6-71. Phosphate-Coated Cylinder with Corrosion .............................................6-115
Figure 6-72. Cylinder Barrel Scoring and Piston Rub ..................................................6-116
Figure 6-73. Typical Wear in Upper Ring Travel .........................................................6-116
Figure 6-74. Typical Cylinder Wear .............................................................................6-116
Figure 6-75. Improperly Positioned Baffle Seals ..........................................................6-118
Figure 6-76. Improperly Positioned Baffle Seals ..........................................................6-119
Figure 6-77. Improperly Positioned Aft and Side Peripheral Baffle Seals ...................6-119
Figure 6-78. Improperly Positioned Aft and Side Peripheral Baffle Seals ...................6-120
Figure 6-79. Aft and Side Baffles with Air Gaps ..........................................................6-120
Figure 6-80. Cooling Loss Due to Gaps in Baffle Seals ...............................................6-121
Figure 6-81. Cooling Loss Due to Gaps in Baffle Seals ...............................................6-121
Figure 6-82. Crack in Non-Critical Area of Crankcase, typical ....................................6-124
Figure 6-83. O-200 Engine Crankcase ..........................................................................6-125
Figure 6-84. IO/IOF-240 Engine Crankcase .................................................................6-126
Figure 6-85. O-300 Engine Crankcase ..........................................................................6-126
Figure 6-86. IO/LTSIO/TSIO-360 Series Engine Crankcase .......................................6-127
Figure 6-87. 520/550 Permold Engine Crankcase ........................................................6-127
Figure 6-88. 470/520/550 Sandcast Engine Crankcase .................................................6-128

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Figure 6-89. GTSIO-520 Engine Crankcase .................................................................6-128
Figure 6-90. Induction Tube Bead Location .................................................................6-130
Figure 6-91. Properly Installed Induction Tube, Hose and Clamps ..............................6-130
Figure 6-92. Serviceable Throttle/Mixture Control Lever & Shaft Splines .................6-137
Figure 6-93. Worn Throttle and Mixture Control Lever & Shaft Splines ....................6-138
Figure 6-94. Throttle and Control Assembly Lubrication Points .................................6-140
Figure 6-95. Throttle and Metering Assembly Lubrication Points ...............................6-140
Figure 6-96. Induction Port Drain Connectors ..............................................................6-141
Figure 6-97. Exhaust Slip joint Inspection ....................................................................6-145
Figure 6-98. V-band Clamp Inspection .........................................................................6-145
Figure 6-99. Wastegate Lubrication Points, typical ......................................................6-147
Figure 6-100. Check Valve, Detail .................................................................................6-150
Figure 6-101. Single Turbocharger Lubrication (check valve location), typical ............6-150
Figure 6-102. Dual Turbocharger (check valve location), typical ..................................6-151
Figure 6-103. Check Valve Functional Check ................................................................6-152
Figure 6-104. Alternator Drive Coupling .......................................................................6-155
Figure 6-105. Alternator and Coupling Assembly ..........................................................6-157

Figure 7-1. IO-360-D/DB Altitude Leaning Schedule ..................................................7-11

Figure 7-2. IO-360-ES Altitude Leaning Schedule ......................................................7-12
Figure 7-3. IO-360-ES in Cirrus SR20 Altitude Leaning Schedule .............................7-13
Figure 7-4. IO-550-A Altitude Leaning Schedule ........................................................7-14
Figure 7-5. IO-550-B Altitude Leaning Schedule ........................................................7-15
Figure 7-6. IO-550-C Altitude Leaning Schedule ........................................................7-16
Figure 7-7. IO-55-D, E, F & L Altitude Leaning Schedule ..........................................7-17

Figure 10-1. Fuel Injector Nozzle Identification, typical ................................................10-3

Figure 10-2. Turbo Fuel Injector Nozzle Assembly, typical ..........................................10-5
Figure 10-3. Naturally Aspirated Engine Fuel Injector Nozzles ....................................10-7
Figure 10-4. Alternator and Drive Coupling .................................................................10-10
Figure 10-5. Alternator Drive Hub Spanner Wrench ....................................................10-12
Figure 10-6. Alternator and Drive Hub .........................................................................10-15
Figure 10-7. Alternator and Drive Hub .........................................................................10-15
Figure 10-8. Multi-Part Alternator Drive Hub ..............................................................10-17
Figure 10-9. One Piece Alternator Drive Hub ..............................................................10-17
Figure 10-10. Continental Ignition System .....................................................................10-23
Figure 10-11. Champion (Slick) Ignition System ...........................................................10-26
Figure 10-12. Continental Pressurized Magneto Filter, typical ......................................10-28
Figure 10-13. Champion (Slick) Pressurized Magneto Filter, typical ............................10-30
Figure 10-14. Cylinder Base O-Ring supporting Connecting Rods ...............................10-33
Figure 10-15. Cylinder Base (Flange) Fasteners ............................................................10-35
Figure 10-16. Cylinder Torque Sequence .......................................................................10-37
Figure 10-17. Cylinder Position Number Location ........................................................10-38
Figure 10-18. NiC3 Cylinder Bore Cross Hatch .............................................................10-41
Figure 10-19. 5.250 Inch Cylinder Measurement Locations ..........................................10-45
Figure 10-20. 5.000 Inch Cylinder Measurement Locations ..........................................10-47

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Figure 10-21. 4.438 Inch Cylinder Measurement Locations ..........................................10-48
Figure 10-22. 4.062 Inch Cylinder Measurement Locations ..........................................10-49
Figure 10-23. Ring Gap Measurement Location .............................................................10-50
Figure 10-24. Intake Valve Angle ...................................................................................10-55
Figure 10-25. Part No. 530864 Counterweight Assembly ..............................................10-77
Figure 10-26. Part No. 531017 Counterweight Assembly ..............................................10-77
Figure 10-27. Part No. 639196 Counterweight Assembly ..............................................10-78
Figure 10-28. Part No. 639197 Counterweight Assembly ..............................................10-78
Figure 10-29. Part No. 639195 Counterweight Assembly ..............................................10-79
Figure 10-30. Part No. 639199 Counterweight Assembly ..............................................10-79
Figure 10-31. Part No. 652833 Counterweight Assembly ..............................................10-80
Figure 10-32. Part No. 627821 Counterweight Assembly ..............................................10-80
Figure 10-33. Part No. 639205 and 639210 Counterweight Assemblies ........................10-81
Figure 10-34. Crankshaft Counterweight Bump Service Inspection ..............................10-82
Figure 10-35. Counterweight Bushing Bore Inspection ..................................................10-84
Figure 10-36. Counterweight Inspection, Repair and Installation ..................................10-86
Figure 10-37. GTSIO-520 Counterweight Inspection, Repair and Installation ..............10-87
Figure 10-38. Crankshaft Hanger Blade Bushing Replacement .....................................10-89
Figure 10-39. Crankshaft Oil Control Plug Leak Test ....................................................10-91
Figure 10-40. Crankshaft Helix Pattern ..........................................................................10-92
Figure 10-41. Connecting Rod Dimensions ....................................................................10-95
Figure 10-42. Retainer Plate and Screws on Front of Crankcase ..................................10-101
Figure 10-43. Crankshaft Nose Oil Seal Parts ..............................................................10-102
Figure 10-44. Split Nose Oil Seal Parts ........................................................................10-105

Figure 11-1. Gear Inspection Criteria .............................................................................11-2

Figure 11-2. Crankshaft Ultrasonic Inspection Method Location ...................................11-8

Figure B-1. Torque Wrench ............................................................................................ B-4

Figure B-2. Drive Extensions ......................................................................................... B-4
Figure B-3. Adjusted Torque Wrench Setting ................................................................ B-4
Figure B-4. Extension, Increases Adjusted Torque Wrench Setting .............................. B-5
Figure B-5. Extension, Decreases Adjusted Torque Wrench Setting ............................. B-5

Figure C-1. Right-Hand Thread Safety Wire Installation ............................................. C-10

Figure C-2. Safety Wire Patterns for Right-Hand Threads ........................................... C-11
Figure C-3. Tab Washer Installation ............................................................................. C-12
Figure C-4. Heli-Coil Extraction Tool .......................................................................... C-14
Figure C-5. Installing a Helical Coil Insert ................................................................... C-15
Figure C-6. Rosan® Stud Removal .............................................................................. C-17
Figure C-7. Stud Sizes .................................................................................................. C-18
Figure C-8. Minimum Material Thickness for Helical Coil insertion .......................... C-18
Figure C-9. Rosan® Stud Installation Dimensions ....................................................... C-19
Figure C-10. Cotter Pin Installation ................................................................................ C-20
Figure C-11. Installing Hoses and Fittings ..................................................................... C-24

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 Introduction
Chapter 1. Introduction
1-1. Scope and Purpose of This Manual
This manual provides maintenance instructions for spark ignition, piston aircraft engines
operating on aviation gasoline (AvGas). These Instructions for Continued Airworthiness
(ICAs) are supplied to the owner with the engine. Instructions in this manual are standard
practices, with differences identified by model, for A-65, A-75, C-75, C-85, C-90, C-125, C-
145, E-165, E-185, E-225, O-200, O-240, IO-240, IOF-240, GO-300, O-300, IO-346, IO-
360, LTSIO-360, TSIO-360, O-470, IO-470, TSIO-470, GTSIO-520, IO-520, LTSIO-520,
TSIO-520, IO-550, IOF-550, TSIO-550, TSIOF-550, TSIOL-550 and TIARA (6-285 and 6-
320) series aircraft engines. For information specific to the Continental engine series,
accessories, or the airplane, refer to the appropriate manual. For the specific instructions
regarding the electronic equipment on FADEC engines, or for unlisted engine models, refer
to the primary ICA.
A list of tools for all applicable engines is provided in Chapter 2. Consumables items, such
as lubricants, sealants, and adhesives are listed in Chapter 3. Airworthiness limitations are
in Chapter 4. Chapter 5 contains generic installation instructions applicable to our engines.
Chapter 6 provides schedule inspection and service intervals and instructions, as well as
unscheduled maintenance instructions. Chapter 7 contains general engine operating
instructions, applicable to all models. Chapter 8 contains engine troubleshooting
instructions. Engine preservation and storage instructions are in Chapter 9. Non-overhaul
engine part replacement instructions are in Chapter 10. Chapter 11 contains Non-
Destructive Inspection guidelines. Chapter 12 contains part cleaning instructions.
Appendix A contains a glossary of common terms and acronyms used throughout the
manual; Appendix B provides torque specifications, and Appendix C contains
maintenance standards.
1-1.1. Instructions for Continued Airworthiness
CAUTION: Instructions in Continental document number 
M-0, Standard Practice Maintenance Manual, do not apply and shall
not be used to maintain Continental Prime or Titan engine products.
Continental document Part No. M-0, is supplemental, as defined by Title 14 CFR§33.4, to
the maintenance and overhaul manuals listed below. Together, this manual and those listed
below comprise the instructions for continued airworthiness for applicable engines. This
manual, and the overhaul manuals and component service manuals (as applicable to
engine specification) listed below are delivered to the customer with the engine. Service
documents and Airworthiness Directives may also affect ICAs. Refer to Section 1-2.5 for
instructions to check current publication status.
Part No. Title Applicability
M-2 Maintenance and Overhaul Manual O-200-D, X
M-6 Maintenance and Overhaul Manual IO-240
M-7 Maintenance and Overhaul Manual IO-360
M-8 Maintenance and Overhaul Manual L/TSIO-360

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Introduction
M-11 Maintenance Manual IO-520 Permold
M-16 Maintenance and Overhaul Manual IO-550 Permold
M-18 Maintenance and Overhaul Manual TSIO-550 Permold
M-22 Maintenance and Overhaul Manual IOF-240
M-24 Maintenance Manual IOF-550-A, B, C, G, N, P & R
M-26 Maintenance and Overhaul Manual TSIOF-550
OH-15 Overhaul Manual TSIOL-550-C
OH-24 Overhaul Manual IOF-550
OMI-15 Operation, Maintenance and TSIOL-550-C
Installation Manual
X30008 Overhaul Manual A-65, A-75
X30010 Overhaul Manual C-75, C,85, C90, O-200-A, B
X30013 Overhaul Manual C-125, C-145, O-300
X30016 Overhaul Manual E-165, E-185, E-225
X30019 Overhaul Manual GO-300
X30027 Overhaul Manual IO-346
X30033 Overhaul Manual TSIO-470
X30039 Overhaul Manual IO-520
X30045 Overhaul Manual GTSIO-520
X30092 Overhaul Manual O-240 (Rolls-Royce)
X30144 Overhaul Manual TIARA 6-285 and 6-320
X30531 Alternator Service Instructions Continental alternators
X30574 Overhaul Manual TSIO-520-B, BB, BE, D, DB,
DB, E, EB, J, JB, K, KB, L, 
LB, N, NB, U, UB, VB, 
WB Permold series
X30575 Overhaul Manual LTSIO-520-AE
TSIO-520-C, CE, G, H, M, P,
R, T, AE, AF Sandcast series
X30586 Overhaul Manual O-470-A, B, E, G, J, K, L, M
R, S, U
X30588 Overhaul Manual IO-470-C, D, E, F, G, H, J, K,
L, M, N, P, R, S, U, V, VO
X30592 Starter Service Instructions Energizer® starters
X30600 Overhaul Manual TSIOL-550-A
X30601 Maintenance and Operator’s Manual TSIOL-550-A
X30605 Maintenance Manual IO-550-D, E, F & L
X30607 Overhaul Manual IO-550-D, E, F & L

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 Introduction
1-1.2. Advisories
This manual utilizes three types of advisories; defined as follows:
WARNING
A warning emphasizes information which, if disregarded, could
result in severe injury to personnel or equipment failure.
CAUTION: Emphasizes certain information or instructions, which if
disregarded, may result in damage to the engine or accessories.
NOTE: Provides special interest information, which may facilitate
performance of a procedure or operation of equipment.
Warnings and cautions precede the steps to which they apply; notes are placed in the
manner which provides the greatest clarity. Warnings, cautions, and notes do not impose
undue restrictions. Failure to heed advisories will likely result in the undesirable or unsafe
conditions the advisory was intended to prevent. Advisories are inserted to ensure
maximum safety, efficiency, and performance. Abuse, misuse, or neglect of equipment can
cause eventual engine malfunction or failure.
1-1.3. Effectivity Symbols
Variations in engine configuration may require specific instructions or illustrations. When
information pertains to only a subset of the applicable engine models, an effectivity
symbol will precede the information. Effectivity symbols found in this publication are:
FWD Forward Mounted Gear Driven Alternator
AFT Aft Mounted Gear Driven Alternator
EZR Energizer Starter
SKY SkyTec Starter

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Introduction
1-1.4. Using this Manual
This manual, the primary engine ICA listed in Section 1-1.1, applicable FAA ADs and
Continental service documents, the accessory manuals listed in Table 1-2, and all changes
incorporated in the ICAs as revisions constitute the Instructions for Continued
Airworthiness (ICAs) prepared by Continental and accepted by the FAA. We prepared this
manual in a user-friendly format suited equally for electronic viewing and print.
Illustrations in this manual are for reference only, depicting the most prominent
configuration in the engine series. Consult the electronic illustrated parts catalog for
engine model-specific illustrated parts breakdowns. The current information available
from Continental must be used to perform engine service, repair or overhaul.
Continental provides Instructions for Continued Airworthiness based on the design,
testing, and certification of engines and parts for which Continental Motors, Inc. is the
holder of the Type Certificate (TC) or Parts Manufacture Approval (PMA) issued by the
Federal Aviation Administration (FAA).
WARNING
Continental ICAs are applicable only to Continental engines
conforming to the approved, type certified engine model
configuration. Continental ICAs must not be used for
aftermarket parts or products modified by Supplemental Type
Certificate.
Installation of aftermarket parts on a Continental engine constitutes a deviation from type-
design criteria. Continental has not participated in design, test, or certification of any
aftermarket parts. Continental does not provide product manufacturing specifications to
aftermarket parts manufacturers and accepts no liability for the suitability, durability,
longevity, or safety of such parts installed on Continental engines. Installation of
aftermarket parts on a Continental engine must be performed using Instructions for
Continued Airworthiness prepared by the manufacturer and approved by the FAA for the
subject installation. For work with the engine installed in the aircraft, the aircraft
maintenance manual may also be required to gain access to, perform maintenance, or
install some items. Use only the current information from the aircraft manufacturer.
Exploded assembly illustrations accompany instructions throughout the manual. Parts in
illustrations (Figure 1-1) are identified with either alpha or numerical callouts (indexes).
Corresponding parts listings follow the illustrations for reference. The first time
instructions refer to an illustration, the figure number is identified in parentheses, followed
by the callout. In subsequent parts references, only the callout will be specified unless the
referenced illustration changes.

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 Introduction

Figure 1-1. Figure and Index Reference

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Introduction
1-1.5. Compliance
The owner/operator is responsible for ensuring the engine is maintained in an airworthy
condition, including compliance with FAA Airworthiness Directives. Engine service life
is calculated based on compliance with the aircraft and engine manufacturer’s required
instructions, inspections, and maintenance schedule. Failure to comply may void the
engine warranty.
WARNING
Prior to authorizing engine maintenance, the owner must
ensure the facility or mechanic meets the Federal Aviation
Administration (or equivalent authority) regulatory
requirements. The engine owner must verify the repair facility
or mechanic uses the most current revision, including change
pages of the applicable ICA. Use of Instructions for Continued
Airworthiness which have been designated as obsolete,
superseded, or inactive is prohibited.
Continental ICAs are written for use by maintenance personnel who possess and apply the
knowledge, training, and experience commensurate with persons holding a valid license
or certification granted by the governing airworthiness authority to return the engine to an
airworthy condition. No other use is authorized.
WARNING
Failure to comply with ICAs may result in personal injury,
death and subsequent engine failure. Each person performing
maintenance, alteration or preventive maintenance on an
engine or accessory must use methods, techniques and practices
set forth in the Instructions for Continued Airworthiness or
other methods, techniques, and practices found acceptable to
the Administrator.
This manual shall be used in conjunction with the latest revision of FAA Advisory
Circular 43.13-1, “Acceptable Methods, Techniques, and Practices” as well as related
publications and accessory manufacturer’s instructions. Pursuant to Title 14 CFR Part 43,
§43.13(a), each person performing maintenance, alteration, or preventive maintenance on
the engine or accessories must use methods, techniques, and practices prescribed in the
ICAs or other methods, techniques, and practices found acceptable by the Administrator.

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 Introduction
1-1.6. Order of Precedence
Continental engine operating instructions are generated prior to and independently of the
aircraft operating instructions. Continental operating instructions are developed using
factory controlled parameters that are not necessarily the same as those specifications
required to satisfy a specific aircraft/engine installation.
WARNING
The aircraft operator must use the aircraft manufacturer’s
operating instructions found in the Airplane Flight Manual/
Pilot’s Operating Handbook (AFM/POH) and applicable
Airplane Flight Manual Supplements (AFMS) while operating
the engine in the aircraft unless the AFM/POH directs
otherwise.
Refer to the AFM/POH published by the aircraft manufacturer for operating instructions
and specifications relative to your aircraft.
Prior to commencing engine maintenance, consult the Continental web site
(www.continental.aero) to verify the current status of the ICAs relating to the intended
procedure.
1-2. Publications
This most current approved version of this manual is delivered to the customer at time of
purchase. This manual and all subsequent revisions or changes are published in Adobe
portable document format (PDF) and available to view or download from Aircraft
Technical Publishers (ATP) web site (www.atp.com).
1-2.1. Publication Access
Printed technical publications may be ordered through Continental technical publications
distributor, Aircraft Technical Publishers (ATP). Contact an ATP customer service
representative to discuss service subscription options and pricing or visit their web site
(www.atp.com).
1-2.2. Publication Changes
WARNING
Use only the latest revision of all publications. Using superseded
information may jeopardize engine airworthiness. Service
documents, published by the manufacturer, or Airworthiness
Directives, published by the FAA, may alter or provide
supplemental information to the Maintenance and Overhaul
Manual. Verify and use only the current versions of all
instructions.
The instructions in this manual represent the best and most complete information available
at the time of publication. Product or process improvements may trigger changes to
existing product design specifications or procedures contained in publications. As new
technical information becomes available, Continental will make the information available
to the customer.

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Introduction
Continental releases publication changes in the form of either change pages or complete
publication revisions, depending upon the extent of change.
Continental issues service documents in the form of Service Bulletins on a wide variety of
topics. Some service documents may affect or supplement information in this manual and
should be reviewed prior to performing maintenance. All active service documents
applicable to standard maintenance practices have been incorporated in these instructions
as of the date of publication.
1-2.3. Update/Change Distribution
Document updates are available on our web site upon notification of FAA document
acceptance/approval. Printed publication subscribers receive printed changes and
revisions as they are released.

Figure 1-2. Change Page Identification

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 Introduction
Document revisions are released if the update changes more than 50% of the contents of a
publication. Revisions replace the previous version of a publication from cover to cover.
Minor corrections are released as change pages to the original publication, identified with
a change number and effective change date in the page footer. Information on the page that
changed from the previous edition is identified by a vertical, six-point black line
(Figure 1-2), referred to as a “change bar” in the outside margin of the page.
A change page replaces only the previous edition of the affected page. In the event a
change page forces repagination, a new page will be inserted with a decimal extension
added to the page number. For example, if additional pages are required between pages 1-
6 and 1-7, the inserted page numbers will be 1-6.1, 1-6.2, and so on until sufficient pages
are added to incorporate the new material.
Page A of the manual contains the original publication date and an itemized list of changes
issued for the technical manual (Figure 1-3). If change pages are issued for the manual, the
change will be identified, with an effective date under the heading “Effective Changes for
This Manual” on Page A. The list of effective pages, itemizes the pages in each section, by
change number. Original pages are designated by a 0 in the List of Effective Pages
“Change” column.

Figure 1-3. List of Effective Pages

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Introduction
1-2.4. Service Documents
Continental may issue Service Documents in one of six categories ranging from mandatory
(Category 1) to informational (Category 6). Definitions of the categories are listed below:

NOTE: Upon FAA approval, Continental publishes service documents for

immediate availability on our web site. The service document cover page
indicates the engine models affected by the service document. Service
documents may alter or replace the manufacturer’s Instructions for
Continued Airworthiness. Insert a copy of applicable Service Documents
in affected manuals until the service document instructions are
incorporated in the manual, or the service document is canceled or
superseded.
1Procedure

Category 1: Mandatory Service Bulletin (MSB)

Used to identify and correct a known or suspected safety hazard which has been incorporated in whole or in
part into an Airworthiness Directive (AD) issued by the FAA or have been issued at the direction of the FAA
by the manufacturer requiring compliance with an already-issued AD (or an equivalent issued by another
country’s airworthiness authority). May contain updates to Instructions for Continued Airworthiness to
address a safety issue.
Category 2: Critical Service Bulletin (CSB)
This category identifies a condition that threatens continued safe operation of an aircraft, persons or property
on the ground unless some specific action (inspection, repair, replacement, etc.) is taken by the owner or
operator. Documents in this category are candidates for incorporation into an FAA Airworthiness Directive.
May contain updates to Instructions for Continued Airworthiness to address a safety issue.
Category 3: Service Bulletin (SB)
Information which the product manufacturer believes may improve the inherent safety of an aircraft or
aircraft component; this category includes the most recent updates to Instructions for Continued
Airworthiness.
Category 4: Service Information Directive (SID)
The manufacturer directs the owner/operator/mechanic in the use of a product to enhance safety,
maintenance or economy. May contain updates to Instructions for Continued Airworthiness in the form of
maintenance procedures or specifications.
Category 5: Service Information Letter (SIL)
This category includes all information (not included in categories 1 through 4) that may be useful to the
owner/operator/technician. May contain updates to Instructions for Continued Airworthiness for optional
component installations, which are not covered in the Applicable Operator, Maintenance, or Overhaul
Manuals.
Category 6: Special Service Instruction (SSI)
This category is used to address an issue limited to specific model and/or serial number engines. We will
distribute SSI notification directly to the affected engine’s owners. SSIs will not be included in the general
service document set but will be made available through our Customer Service Department to owners of the
affected engines only. An SSI may update the applicable engine’s Instructions for Continued Airworthiness.

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 Introduction
1-2.4.1. Service Documents Incorporated in this Manual
Applicable technical maintenance and service information contained in the Service
Documents listed below, relevant to the engine models covered by this engine manual,
have been incorporated in this M-0, Standard Practice Maintenance Manual. This manual
supersedes and retires these Service Documents (and all revisions, where applicable)
excluding Mandatory Service Bulletins (MSBs) and Critical Service Bulletins (CSBs)
identified with an asterisk (*) in Table 1-1 below.
The full content of active Continental Service Documents is a vailable a t
www.continental.aero. Refer to Section 1-3, “Contact Information” for Continental web
site details.
Table 1-1. Service Documents Incorporated in Manual
Affected
Service Document Subject Chapter
M67-12, Overboost of Turbocharged Engines Unscheduled Maintenance 6
M72-17R1, Maximum Weight Difference Between Connecting Rods Parts Replacement 10
and Pistons in the Same Engine
M76-4, Propeller Shaft or Crankshaft Oil Seal Replacement Unscheduled Maintenance 10
M76-8, Intake Valve Change Unscheduled Maintenance 10
M77-3, Use of Alternate Fuels in Engines Originally Certified for 80/ Engine Operation 7
87, 91/96 and 100/130 Grade Fuels
M84-5, Gear Driven Alternator Inspection Procedure Alternator Replacement 10
M85-10, Cylinder Hold Down Nuts Cylinder Replacement 10
M87-15, Alternator Ground Strap Alternator Replacement 10
M88-9, Lightning Strikes Unscheduled Maintenance 6
M88-10, Contaminated Fuels Unscheduled Maintenance 6
M89-7R1, Engine Operation after Cylinder Replacement and/or Unscheduled Maintenance 7
Major Overhaul
M89-9, Excessive Crankcase Pressure Unscheduled Maintenance 8
M90-17, Crankcase Inspection Criteria Scheduled Maintenance 6
SIL93-11B, Service Document Format Service Documents 1
SIL93-15, General Practices for Installation of Lock Wire, Tab Standard Practices Appendix C
Washers, and Cotter Pins
* MSB94-8D, Magneto to Engine Timing Scheduled Maintenance 6
SB95-2, Inspection and Maintenance of Engine Control Cables and Inspection 6
Linkage
SB95-3B, Alternator/Generator Drive Coupling Alternator Maintenance 6, 10
SIL95-5, Hose and Tubing Installation Hose and Tubing Installation Appendix C
SB96-7D, Torque Limits Fastener Torque Appendix B
* MSB96-10B, Crankshaft Ultrasonic Inspection Engine Overhaul or 10
Crankshaft Repair

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Introduction
Table 1-1. Service Documents Incorporated in Manual
Affected
Service Document Subject Chapter
SB96-11B, Propeller Strikes and Hydraulic Lock Unscheduled Inspection 6
SB96-12, Cylinder Continued Airworthiness Scheduled Inspection 6 & 10
SID97-2B, Design, Operation Maintenance and Warranty of Engine Maintenance 6
Cylinders
SID97-3G, Continuous Flow Fuel Injection Systems Adjustment Operational Checks and 6
Specifications and Instructions Adjustments
SID97-4F, Cylinder Bore and Piston Fit Specifications Overhaul & Service Limits 10
SB97-6B, Mandatory Replacement Parts Engine Inspection & Assembly Appendix C
SIL98-9E, Time Between Overhaul Periods Scheduled Maintenance 6
SIL99-1, Engine Preservation for Active and Stored Aircraft Engine Preservation and 9
Recovery
SIL99-2C, Sealants, Lubricants and Adhesives Authorized by CMI Materials 3
SB00-3A, Crankshaft, Counterweight and Connecting Rod Repair Repair Specifications 10
Information
SIL00-9A, Engine Data Plates Data Plate Replacement Appendix C
SIL00-11B, Release of new Cylinder Induction Port Drain Connector Cylinder Assembly 10
SIL03-1, Cold Weather Operation - Engine Preheating Engine Operation 7
SIL03-2C, Currently Active Approved Spark Plug Application Spark Plugs 6
SB03-3, Differential Pressure Test and Borescope Inspection Inspection Criteria 6
SIL04-12A, Authorized Engine Adjustments, Component Engine Specification 5
Replacement and Repositioning
SB05-2, Overspeed Limitations Unscheduled Maintenance 6
*CSB08-3C, Throttle & Mixture Control Levers Fuel Injection System 6
Assembly
SB08-13, Induction System Hose and Clamp Installation Induction System Inspection & 6
Assembly
SB11-3, Alternator and Drive Coupling Installation Alternator Replacement 6, 10
SIL13-2A, Alternator Instructions for Continued Airworthiness Alternator Replacement 6, 10
SB14-8, Exhaust Flange to Cylinder Installation Exhaust System Installation 10
SB16-3, Turbocharger Check Valve Inspection and Cleaning Exhaust System Inspection 6
SB17-01A, Flanged Nut Inspection and Corrosion Prevention Cylinder Inspection 6
SIL17-02, Turbocharger Check Valve Filter Installation, Inspection, Maintenance Criteria 6, 8,
and Cleaning Appendix C
SIL17-03, Oil Filter Anti-stick Gasket Oil and Filter Change 6
* Documents remain active in the service bulletin set.

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 Introduction
1-2.4.2. Service Documents Released After Publication
Continental strives to provide clear, concise, and accurate information and instructions
based on best known engineering data at the time of publication. Ongoing process
improvements may change a specification or procedure after a manual is released. Service
documents, defined in Section 1-2.4, expedite customer notification until the new
information is incorporated in the manual text. As service documents are received, note
the service document number, release date, title, and applicable section affected by the
service document in the blank cells below and insert a copy of the service document
behind the last page of this section. Make pen & ink corrections, where appropriate, to the
original text in the manual with a citation to the service document; i.e. see SB9X-1. For
paragraphs or entire sections, draw an “X” through the affected information in the manual
and reference the service document containing the correction
Service Documents Release After This Manual
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:

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Introduction
Service Documents Release After This Manual
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:
Document Number: Release Date: / / Affected Sections:
Title:

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 Introduction
1-2.5. Related Publications
The table below lists the publications, source, and accessibility relevant to Standard
Practice installation, maintenance, and overhaul.
WARNING
Use only the latest revision of all publications. Using superseded
information can jeopardize engine airworthiness.
CAUTION: Instructions in M-0, Standard Practice Maintenance Manual, do
not apply and shall not be used to maintain Continental Prime or Titan
engine products.

Table 1-2. Related Publications1

Electronic Printed
Document Part Supplied Download Manual
Number (P/N) Publication Title With Engine Available Available
Instructions for Continued Airworthiness
M-0 
(this manual) Standard Practice Maintenance Manual2 Yes Yes Yes
X30531 Alternator Service Support Manual Yes Yes Yes
X42001 Magneto Service Support Manual (S-1200 Series) Yes Yes Yes
X42002 Magneto Service Support Manual (S-20/200 Series) Yes Yes Yes
Illustrated Parts Catalogs
by Engine
Model/ Electronic Engine Product Catalog No Yes (view only) No
Specification
1. Our web site (www.continental.aero) provides daily 24-hour access to current service documents and the technical publications Index.
Continental is partnered with Aircraft Technical Publishers (ATP, (www.atp.com) to distribute our technical publications on their subscription
web site. If you have not subscribed to ATP and are using printed manuals, verify & confirm you have the latest applicable revision with
either a service representative (using the “Contact Information” in Section 1-3) or the Service Document Index.
2. Instructions in M-0, Standard Practice Maintenance Manual, do not apply and shall not be used to maintain Continental Prime or Titan
engine products.

1-2.5.1. Suggestions and Corrections

Continental solicits and encourages user comments regarding suggested changes to this
manual. Direct recommended changes or questions to the attention of “Publications” at the
address listed in Section 1-3, “Contact Information” or send comments via e-mail to
cm.techpubs@continental.aero.
Notify our Customer Service Department immediately if you discover incorrect
information which adversely affects safety.

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Introduction
1-3. Contact Information
Continental factory representatives are available to answer technical questions and
encourages suggestions regarding products, parts, or service. If customers have an inquiry
or require technical assistance, they should contact their local Continental distributor or
field representative. To contact a factory representative, refer to the contact information
below:
Continental Aerospace Technologies
P. O. Box 90
Mobile, AL 36601
Customer Service Department:
Toll free within the continental United States: 1-888-826-5465
International: 1-251-438-8299
Internet: www.continental.aero
1-4. Service Parts
Continental engineering staff develops a complete bill of materials for every engine model
specification manufactured. Due to our diverse customer base of aircraft OEM and STC
application builders, engine model specifications are developed to accommodate the
aircraft manufacturer’s specifications. While many parts fit multiple engine model
specifications, interchangeability of parts from one engine model, or model specification,
to another is not guaranteed.
1-4.1. Service Part Applicability and Availability
Major engine assemblies and components are permanently identified (steel stamped,
engraved, laser etched, or ink-stamped) with a unique part number during the
manufacturing process. The latest revision of the Illustrated Parts Catalogs is available on
our web site to locate Continental parts for current production engine model specifications
and heritage products (no longer in production).
Some parts of assemblies are not available for aftermarket sale for various reasons. Some
assemblies are not intended to be disassembled, such as cylinder heads and barrels. For
this reason, only the next higher assembly (NHA) is available for aftermarket sales.
1-4.2. Part Supersedure
Innovation and continuous improvements are core values at Continental. The original part
numbers used to manufacture your aircraft engine may or may not be available when
replacement parts are needed to restore the engine to an airworthy condition. Due to
design improvements to the form, fit, or function of the engine part or assembly, it may be
necessary to supersede the older part number (used to build the original engine model
specifications) and provide a new replacement part or assembly number.
The simplest way to determine the correct part number can be found by comparing the
markings on the existing part(s) to part numbers in the Illustrated Parts Catalog (IPC).
To determine if a part number used to assemble your engine has been superseded, consult
the Parts Supersedure History page on our web site.

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 Tools
Chapter 2. Tools
2-1. Special Tools
NOTE: Special tools listed in Table 2-1 are for reference only, not for the
purpose of promoting or requiring the customer to purchase from a
particular provider. The providers listed are potential sources for the
items based on information available at the time of printing. Customers
are free to obtain equivalent items from alternate sources which meet or
exceed specifications of the listed tools. For FADEC special tools,
reference the primary ICA.

Items with Continental part numbers may be purchased directly from
Continental.

Special tool vendor contact information is listed in Table 2-2.
Table 2-1. Special Tools List

Special Tool Use or Reference Suggested Providers Part Number1

Maintenance
0-60 psi Pressure
Gauge (graduated in 1- Engine Operational Check Davis Instruments Various
psi increments)
0-30 psi Pressure
Engine Operational Check
Gauge (graduated in Davis Instruments Various
(normally aspirated engines only)
0.2-psi increments)
0-30 psid Differential
Pressure Gauge Engine Operational Check
Davis Instruments Various
(graduated in 0.2 psi (turbocharged engines only)
increments)
Alternator Drive Hub Forward Mounted Alternator Drive Hub
Ideal Aviation 9001-IA
Spanner Wrench Assembly Inspection
Alternator Drive Hub Forward Mounted Alternator Drive Hub Fabricate according to
---
Torque Tool Slippage Inspection Figure 2-5
Alternator Drive Hub Aft Mounted Alternator Drive Hub Slippage Fabricate according to
---
Torque Tool Inspection Figure 2-6
Bearing Installation Tool
Fabricate according to
(Worm Gear Roller 90° offset Starter Adapter Assembly ---
Figure 2-15
Bearing)
Belt Tension Gage Drive Belt Tension Adjustment Ideal Aviation BT-33-73FIA
AUTOSCOPETM
Borescope Cylinder Borescope Inspection Q.A. Technologies Lenox Instrument
Company
Differential Pressure Eastern Technology
Cylinder Differential Pressure Test Model E2M
Tester Corporation
Commercial, off the
Digital Multimeter Troubleshooting ---
shelf
High Tension Lead Test Eastern Technology
Ignition Harness Troubleshooting E5
Kit Corporation

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15 Sep 2019
Tools
Table 2-1. Special Tools List

Special Tool Use or Reference Suggested Providers Part Number1

7/16” Injector Nozzle
Removal/Installation Fuel Injector Removal And Installation Ideal Aviation 8167-IA
Tool
1/2” Injector Nozzle
Removal/Installation Fuel Injector Removal And Installation Ideal Aviation 8168-IA
Tool
Aircraft Tool Supply AA470
Oil Filter Can Cutter Cut Oil Filter Can Aircraft Tool Supply FC-2000
Champion Aerospace CT-923
Aircraft Tool Supply AA472
Oil Filter Torque Wrench Oil Filter Installation
Champion Aerospace CT-921
Approved Aircraft
Porta-Test Unit Engine Operational Check Model 20 ATM-C
Accessories (Aero Test)
Portable Digital EGT/
Verify EGT/CHT/TIT Accuracy Alcor, Inc. ALCAL 2000
CHT Tester
Protractor/Timing
Eastern Technology
Indicator Disc and Engine Timing E25
Corporation
TDC Locator
Pulley Alignment Tool Belt Drive Pulley Alignment Ideal Aviation 8082-IA
Pulley Puller Remove Generator/Alternator Sheave Ideal Aviation 61-5IA
Eastern Technology
Timing Light Magneto to Engine Timing E50
Corporation
Worm Shaft Tool &
Fabricate according to
Starter Adapter Starter & Starter Adapter Disassembly ---
Figure 2-7
Disassembly Tool
Overhaul
Bearing Puller Component Maintenance Borroughs*** 8093C
8116-1B through -
Boring Bars Cylinder Repair Borroughs***
15B
2847-2CP
Carbide Tipped Reamer Valve Guide Reaming Kent-Moore***
2847-1CP
Common Drive Handle Cylinder Repair Borroughs*** 8122A
Common Parts Kit Valve Seat Replacement Borroughs*** 8116
Connecting Rod Boring Connecting Rod Piston Bushing
Borroughs*** 8111A
& Alignment Fixture Replacement
Connecting Rod
Connecting Rod Piston Bushing
Bushing Removal/ Borroughs*** 8098
Replacement
Installation Set
Connecting Rod
Bushing Installation and Connecting Rod Piston Pin Bushing
Borroughs*** 8042C
Removal Tool Adapter Replacement
Kit
Connecting Rod Kent-Moore*** 5008
Connecting Rod Bushing Bore Honing
Bushing Reamer Borroughs*** 8071
Commercial, off the
Contact Profilometer Cylinder Bore Honing N/A
shelf

2-2 Standard Practice Maintenance Manual

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 Tools
Table 2-1. Special Tools List

Special Tool Use or Reference Suggested Providers Part Number1

Counterweight Hanger Blade Bushing
Counterweight Bushing
Replacement And Counterweight Bushing Borroughs*** 4965A
Remover/Replacer Tool
Replacement
Fabricate according to
Crankcase Needle
Crankcase Assembly Figure 2-16 (Permold) ---
Bearing Installer Tool
Figure 2-17 (Sandcast)
Crankcase Splitter Separate The Crankcase Kent-Moore*** L423
Crankcase Through
Crankcase Disassembly Borroughs*** 8114-8
Bolt Remover
Crankshaft
Counterweight Bushing
Crankshaft Overhaul Borroughs*** 8077C
Removal/Installation
Fixture
Crankshaft Hanger
Blade Bushing
Crankshaft Overhaul Borroughs*** 8077A
Removal/Installation
Tool
Crankshaft Nose Oil Crankshaft Nose Oil Seal Installation
Kent-Moore*** 5209
Seal Installer Tool Not require for split type nose oil seals
5203, 5204, &
Cylinder Base Nut Kent-Moore*** 8158A, 3882, &
Cylinder Maintenance 3882-2
Wrenches
Borroughs*** 8079
Cylinder Heating Stand Cylinder Maintenance Borroughs*** 8156
Valve Seat Replacement
Cylinder Holding Fixture Valve Guide Replacement Borroughs*** 5221B
Valve Seat Machining
Valve Seat Replacement 5221-13A
Cylinder Holding Fixture
Valve Guide Replacement Borroughs*** 5221-15A
Adapters
Valve Seat Machining 5221-16A
Cylinder Hone Engine Cylinder Bore Honing Snap On Tools CFL10
Commercial, off the
Dial Indicator Gear Backlash Measurement ---
shelf
Exhaust Valve Seat
Grinding Stone Valve Seat Machining Aircraft Tool Supply K95
(Roughening 45)
Exhaust Valve Seat
Grinding Stone Intake Or Exhaust Valve Seat Machining Aircraft Tool Supply K25
(Finishing 45)
Expanding Guide 8116-1 through -
Valve Guide Replacement Borroughs***
Bodies 16
Generator Drive Holder Secure The Generator Drive Borroughs*** 4973
Stanley Engineered
Heli-Coil Extracting Tool Helical Coil Insert Replacement ---
Fastening
Heli-Coil Installation Stanley Engineered
Helical Coil Insert Replacement ---
Tool Fastening

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15 Sep 2019
Tools
Table 2-1. Special Tools List

Special Tool Use or Reference Suggested Providers Part Number1

Heli-Coil Expanding Stanley Engineered
Helical Coil Insert Replacement 520-2
Tool No. 520-2 Fastening
High Speed Steel 2847-1HP
Reaming Valve Guides Kent-Moore***
Reamer 2847-2HP
Intake Valve Seat
Grinding Stone Valve Seat Machining Aircraft Tool Supply K106
(Roughening 30)
Intake Valve Seat
Grinding Stone Valve Seat Machining Aircraft Tool Supply K46
(Finishing 30)
Needle Bearing Installer Starter Adapter Housing Worm Shaft Needle
Borroughs*** 23-1
Tool Bearing Replacement
Fabricate according to
O-ring Installation Tool Crankcase Hardware Installation ---
Figure 2-19
Fabricate according to
Oil Control Plug
Oil Control Plug Replacement Figure 2-10 through ---
Installation Tool
Figure 2-11
Oil Control Plug Leak Fabricate according to
Oil Control Plug Replacement ---
Test Fixture Figure 2-12
Oil Pressure Relief Spot
Oil Pressure Relief Valve Seat Refacing Kent-Moore*** 8048
Facer
Crankcase And Accessory Drive Adapter Oil Fabricate according to
Oil Seal Tool ---
Seal Installation Figure 2-20
Piston Ring
Engine Cylinder Installation Kent-Moore*** 3601
Compressor
Piston Ring Removers Piston Ring Removal Kent-Moore*** 8121
Polishing Tool Engine Drive Train Inspection Burroughs*** 8087B
Pushrod Spring
Pushrod Installation Kent-Moore 68-3
Compressor Tool
8116-1R through -
Reamers Valve Guide Reaming Borroughs***
15R
Reamer, Adjustable Magneto Drive Adapters Bushing And Oil Size range 25132-
Borroughs***
Blade Seal Installation 27132
Rocker Arm Bushing Rocker Arm Bushings (Single-Bushing
Kent-Moore*** 8118
Remover/Installer Type) Replacement
Rocker Arm Bushing
Ream Rocker Arm Bushing Kent-Moore*** 7232
Reamer
McMaster-Carr Supply
Rosan Stud Remover Remove Rosan Studs Company
2769A13

Rosan Lock Ring Rosan Studs Installation Kent-Moore*** 8074

Installer
Spark Plug Insert
Spark Plug Heli-coil Insert Removal Borroughs*** 4919
Remover
Spark Plug Insert
Spark Plug Heli-coil Insert Installation Borroughs*** 4918
Replacer

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 Tools
Table 2-1. Special Tools List

Special Tool Use or Reference Suggested Providers Part Number1

Spark Plug Tap 
Repair Damaged Spark Plug Threads/Boss Borroughs*** 445
(18 mm)
Test Club Post-Overhaul Testing Hartzell Propeller, Inc.
Valve Guide Boss 4943-1 HS
Valve Guide Reaming Kent-Moore***
Reamers through -5HS
Valve Guide Floating
Valve Guide Replacement Borroughs*** 3170
Holder
Valve Guide Remover Valve Guide Replacement Kent-Moore*** 4981
Valve Guide Seal Fabricate according to
Valve Guide Seal Installation ---
Installation Tool Figure 2-18
Valve Seat Grinder Set
Machining Intake Or Exhaust Valve Seat Aircraft Tool Supply 1675
“Sioux Brand”
Valve Seat Grinder Pilot
Machining Intake Or Exhaust Valve Seat Aircraft Tool Supply AEX 437
0.437 diameter
Valve Seat (Straight
Valve Seat Repair Kent-Moore*** 5224 & 5225
Side) Insert Cutters
Valve Seat (Step Side) 8135, 8136, &
Valve Seat Repair Kent-Moore***
Insert Cutters 8138
Valve Seat Insert
Valve Seat Replacement Borroughs*** 8086
Remover & Replacer
Valve Spring
Engine Cylinder Assembly Kent-Moore*** 3602
Compressor Tool
Overhaul Inspection
Parker Research
Contour Probe Magnetic Particle Inspection DA-200
Corporation
Federal Dimension Air
Gage (with setting ring
Counterweight Hanger Blade Bushing
and air plug) or
Replacement MAHR Federal D-4000
equivalent with
Counterweight Bushings Replacement
1.1268 Setting Ring
1.1268 Air Plug
Cylinder Bore Inner Diameter Dimensional
Dial Bore Gauges MAHR Federal 545-116
Inspection
Plug Gauge Cylinder Intake Valve Guide Inspection Kent-Moore*** 2848-1
Krautkramer-
Branson P/N:
USK 7D OR7S
Ultrasonic Test
Crankshaft Ultrasonic Inspection Krautkramer-Branson USL 42
Instrument, Portable
USL 48
USN 50
USN 52
Ultrasonic Test DSC Block or
Crankshaft Ultrasonic Inspection
Instrument Calibration Krautkramer-Branson Rompas Block
(Equipment Calibration)
Block (steel)
Coaxial Cable - Grade Crankshaft Ultrasonic Inspection Krautkramer-
74 RG174/U 50 ohm (For Connecting The Transducer To The Krautkramer-Branson Branson P/N
Microdot to BNC (6’) Ultrasonic Equipment) 118140012

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15 Sep 2019
Tools
Table 2-1. Special Tools List

Special Tool Use or Reference Suggested Providers Part Number1

Krautkramer-
Coaxial Cable MMD to
Cylinder Barrel Ultrasonic Inspection Krautkramer-Branson Branson P/N
BNC (6’)
C-047
Krautkramer-
Filter (microhenry BNC
Cylinder Barrel Ultrasonic Inspection Krautkramer-Branson Branson P/N 281-
to BNC)
678-200
Krautkramer-
Fixture 60 Axial Cylinder Barrel Ultrasonic Inspection Krautkramer-Branson Branson P/N
291-678-000
Krautkramer-
Flaw Detector Cylinder Barrel Ultrasonic Inspection Krautkramer-Branson Branson P/N USL-
42 or equivalent
Krautkramer-
Transducer 5.0 MHz, Branson P/N
Cylinder Barrel Ultrasonic Inspection Krautkramer-Branson
0.125 diameter SMSWS 113-214-
585
Krautkramer-
Transducer, Miniature Crankshaft Ultrasonic Inspection
Krautkramer-Branson Branson P/N
(Gamma Series 5 MHz) (Provide Piezoelectric Effect)
MSWS 224-580
Crankshaft Main
Bearing 2.2375 –
Crankshaft Ultrasonic Inspection Continental 654478-1
2.2485 inches (5.6833 –
5.7112 cm) and
Miniature Wedge 
Crankshaft Ultrasonic Inspection Continental 654484
(45 shear wave)
Crankshaft Main
Bearing 2.3630 –
Crankshaft Ultrasonic Inspection Continental 654483-1
2.3750 inches (6.0020 –
6.0325 cm) and
Miniature Wedge 
Crankshaft Ultrasonic Inspection Continental 654578
(45 shear wave)
Crankshaft Main
Bearing 2.6140 –
2.6250 inches  Crankshaft Ultrasonic Inspection Continental 654485-1
(6.6396 – 6.6675 cm)
and
Miniature Wedge 
Crankshaft Ultrasonic Inspection Continental 654484
(45 shear wave)
Micrometers (series 3
Counterweight Hanger Blade Bushing
point contact inside Starrett No. 78
Replacement
micrometers)
Runout Block Set Drive Train Dimensional Inspection Borroughs*** 8117a
*or equivalent
**Providers can be subject to change or discontinue manufacturing tools
*** The rights to manufacture Borroughs and Kent-Moore tools has been acquired by Kell-Strom Tool Company.
1. Items with Continental part numbers may be purchased directly from Continental.

2-6 Standard Practice Maintenance Manual

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 Tools
2-1.1. Vendor Contact Information
Table 2-2. Tools, Accessories, and Supply Vendors

Supplier Address Phone FAX Web Address1

American Lubricants / 1227 Deeds
Moly Motor Oil Dayton, OH 45401 937-222-2851 618-534-5231 molymotoroil.com
P.O. Box 370
800-248-0638
Aircraft Tool Supply 1000 Old U.S. 23 517-739-1448 aircraft-tool.com
517-739-1447
Oscoda, MI 48750
300 Breesport 800-343-7233
Alcor 210-308-8536 alcorinc.com
San Antonio, TX 78216 210-349-6491
Approved Aircraft 8545 Groh Road
734-675-0278 N/A N/A
Accessories Grosse Ile, MI 48138
A. W. Chesterton 500 Unicorn Park Drive 800-835-4135
781-438-8971 chesterton.com
Company Woburn, MA 01801-3345 781-438-7000
100 Barr Harbor Drive 877-909-2786
ASTM N/A astm.org
West Conshohocken, PA 19428 610-832-9585
Borroughs See Kell-Strom Tools
Champion Aerospace, 1230 Old Norris Road championaerospace.co
864-843-1162 864-843-5402
Inc. Liberty, SC 29657 m
CRC Industries/Chemical 885 Louis Drive 800-272-4620 800-272-4560
crcindustries.com
Products Warminister, PA 18974 800-556-5074 215-674-2196
625 E. Bunker Ct. inotek.com
Davis Instruments 800-358-5525
Vernon Hills, IL 60061 davis.com
Daubert Chemical 4700 South Central Ave Chicago, 708-563-8325 78-496-7367 daubertchemical.com
IL 60638
P.O. Box 997
989-496-4400
Dow Corning Corporation South Saginaw Road dowcorning.com
800-662-0661
Midand, MI 48686
Eastern Electronics See Eastern Technology Corporation
Eastern Technology 42 Nelson St.
860-528-9821 860-289-7639 easterntech.com
Corporation East Hartford CT 06108
Federal Mogul Southfield, MI 248-354-7700 federal-mogul.com
Graham Aircraft Engines PO Box 3214
770-252-4995 770-252-5270 www.highaero.com
(Motorstor) Peachtree City, GA 30269
Hartzell Engine Plane Power
Technologies (formerly 2900 Selma Hwy 877-359-5355 334-386-5410 hartzellenginetech.com
Kelly Aerospace) Montgomery, AL 36108
One Propeller Place
Hartzell Propeller Inc. 937-778-4200 937-778-4271 hartzellprop.com
Piqua, OH 45356
32100 Stephenson Hwy
Henkel Aerospace 248-583-9300 248-583-2976 henkel.com
Madison Heights, MI 48071
564 Juanita Avenue
Ideal Aviation 480-963-8890 480-963-8887 idealaviation.com
Mesa, AZ 85204
214 Church Street 800-851-6851
Kell-Strom Tool Company 860-257-9694 kell-strom.com
Wethersfield, CT 06109 860-529-6851

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Tools
Table 2-2. Tools, Accessories, and Supply Vendors

Supplier Address Phone FAX Web Address1

Kent-Moore See Kell-Strom Tool Company
metrologyworld.com/
50 Industrial Park Road 717-242-0327
Krautkramer-Branson storefronts/
Lewistown, PA 17044 334-438-3411
krautkramer.html
1001 Trout Brook Crossing 860-571-5100
Loctite 860-571-5465 loctite.com
Rocky Hill, CT 06067-3910 800-243-4874
4647 Hugh Howell Road 800-241-9334
LPS Laboratories 770-243-8899 lpslabs.com
Tucker, GA 30084 770-243-8800
129 Lockwood St. 973-589-9150
Lubriplate 973-589-4432 lubriplate.com
Newark, NJ 07105 800-733-4755
1144 Eddy Street 401-784-3271
MAHR Federal 401-784-3246 mahr.com
Providence, RI 02905 800-343-2050
McMaster-Carr Supply P.O. Box 4355
630-833-0300 630-834-9427 mcmaster.com
Company Chicago, IL 60680-4355
201 W. Mansville Dr. 800-421-1936
Merit Abrasives 800-472-3094 meritabr.com
Compton, CA 90224 310-639-4242
Miller-Stephenson 6348 Oakton St. 847-966-2022
847-966-8468 miller-stephenson.com
Chemical Company Morton Grove, IL 60053 800-992-2424
P.O. Box 61085
Q.A. Technologies 912-330-0500 912-330-0104 qatek.com
Savannah, GA 31420
Plane Power®, see Plane Power
Hartzell Engine 2900 Selma Hwy 877-359-5355 334-386-5410 hartzellenginetech.com
Technologies Montgomery, AL 36108
Parker Research P.O. Box 1406 800-525-3935
727-797-3941 parkreascorp.com
Corporation Dunedin, FL 34697 727-796-4066
P.O. Box 2463 713-241-4819
Shell Oil Company 713-241-6511 shell-lubricants.com
Houston, TX 77252 800-332-6457
Snap On (Tools) 877-740-1900 877-740-1880 snapon.com
Stanley Engineered 4 Shelter Rock Lane stanleyengineeredfaste
877-364-2781 800-225-5614
Fastening Danbury, CT 06810 ning.com
121 Crescent Street 800-541-8887
L.S. Starrett Company 978-249-8495 starrett.com
Athol, MA 01331 978-249-3551
800-443-2136
Tanair (Tanis Aircraft P14871 Pioneer Trail Suite. 200
In Minnesota: 952-224-4426 tanisaircraft.com
Services) Eden Prairie, MN 55347
952-224-4425
U.S. Industrial Tool & 14083 South Normandie Ave. 310-464-8400
310-464-8880 ustool.com
Supply Gardena, CA 90249 800-464-8400
Worldwide Filter 1689 Abram Court
510-483-5122 734-455-3256 mousemilk.com
(Mouse Milk) San Leandro, CA 94577
1. Unless otherwise indicated, type http://www. followed by the Web Address shown in tis column.

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 Tools

Cylinder
Pressure
Regulator Gauge
Pressure
Gauge

Pressure
Regulator

Cylinder
Adapter AIR Master
Slow Fill
IN Orifice
Valve
Valve

Figure 2-1. Model E2M Differential Pressure Tester (built in Master Orifice Tool)

Figure 2-2. Borescope (Autoscope®)

NOTE: Borescopes are available from multiple manufacturers, with
varying levels of features and resolution. The Autoscope® is only one of
the available products.

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Tools

Figure 2-3. Pulley Alignment Tool

Figure 2-4. Porta-Test Model 20 ATM-C

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 Tools

Figure 2-5. Gear Driven Alternator Drive Hub Torque Tool

Used on Permold 520/550 Permold Series Engines

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Tools

Figure 2-6. Alternator Drive Hub Torque Tool

Used on 200/300/240/360 Series Engines

Figure 2-7. Worm Shaft Tool and Starter Adapter Disassembly Tool

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 Tools
NOTE: The Driver for the Oil Control Plug Installation Tool (Figure 2-8
through Figure 2-11) is the same for all installation tools/engine models.

Figure 2-8. Oil Control Plug Installation Tool - 360 Engines

Figure 2-9. Oil Control Plug Installation Tool - 470 Engines

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Tools

Figure 2-10. Oil Control Plug Installation Tool - 520/550 Permold Engines

Figure 2-11. Oil Control Plug Installation Tool - 470/520/550 Sandcast Engines

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 Tools

Figure 2-12. Oil Control Plug Leak Test Fixture

Standard Practice Maintenance Manual 2-15

15 Sep 2019
Tools

Figure 2-13. Needle Bearing Installation Tool - Part 1

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 Tools

Figure 2-14. Needle Bearing Installation Tool - Part 2

Standard Practice Maintenance Manual 2-17

15 Sep 2019
Tools

Figure 2-15. Bearing Installation Tool

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 Tools
Crankcase needle bearing installation tools vary by the depth the needle bearing is
installed. The needle bearing installed depth for:
• Permold crankcases is 9/16” (see Figure 2-16, 0.625”)
• Sandcast crankcases is 1/2” (see Figure 2-17, 0.50”).

Figure 2-16. Crankcase Needle Bearing Installation Tool, Permold

Figure 2-17. Crankcase Needle Bearing Installation Tool, Sandcast

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Tools

Figure 2-18. Valve Guide Seal Installation Tool

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 Tools

Figure 2-19. O-Ring Installation Tool

Medium Knurl
Stamp P/N
On Flat
Mill Flat 1/16 Radius

5/16 1.200 Dia.

1-1/4 Dia. 1/8x45° 0.783 Dia.

Before Knurl 2.00
1.00
3.00 0.68 1.00

Material 1020
Case Harden

Figure 2-20. Oil Seal Tool

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Tools

Figure 2-21. Helical Coil Extraction Tool

Figure 2-22. Helical Coil Insertion Tool

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 Tools

Figure 2-23. Helical Coil Expanding Tool

Figure 2-24. Rosan® Stud Removal Tool

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Tools
2-2. Mechanic’s Tools
The tools listed below are required to perform overhaul procedures on the engines.
Table 2-3. Common Tools
Open-End Wrenches – 1/4-inch through 1-Inch 1/4-inch Slide hammer
Socket Wrenches:
Ratchets:
1/4-inch drive
• 1/4-inch drive
Socket Sizes: 5/32-inch through 1/2-inch
• 3/8-inch drive
3/8-inch or 1/2-inch drive
• 1/2-inch drive
Socket Sizes: 7/16-inch through 1-1/2-inch
Deep Well Sockets:
Heat Gun
1/2-inch drive
(variable intensity/ equipped with a small tip)
Socket Sizes: 7/16-inch drive through 1-inch
Calibrated Torque Wrenches: • Drill, 0.266 (H) Pneumatic drill
• 0 to 1000 in-lbs • 00.339 Drill High speed borer
• 0 to 500 in-lbs • Drill Index
• 0 to 100 ft-lbs
Micrometers Ball Peen Hammer
Allen Wrenches - assortment Pullers
Slotted Screwdrivers – assortment Blind Bearing Remover
Phillips Screwdrivers – Nos. 1 and 2 Vernier Calipers
Safety Wire Pliers Leather or soft plastic Mallet
Common Pliers Small hole gauges, thickness gauges
Diagonal Cutter Pliers Feeler Gauges (leaf-type)
Needle-Nose Pliers C-Clamps
Duck Bill Pliers Brass Wire Brush
Snap Ring Pliers (with 90-degree bend) Stiff-bristled, Non-wire Scrub Brush
Inspection light/flashlight Dry Blaster Cleaning Tool
Two-inch (2”) Merrit Wheel (flap wheel) Air Impact Tool
T-handle Drive Toolmaker’s Square
Magnifying Glass (10X power) Profilometer
Mirror Chamfer Tool
Utility Knife Morse Adapter
Scissors Heavy Duty Drill Press
Crimp Tool Arbor Press (and 8-inch arbors)
Wire Ties Vertical Mill
Ring Expander Engine Hoist
Bench Vise with Shielded Jaws Engine Stand
Fiber Drift, Brass Drift, Pin or Punch Transport dolly
Magnet Aircraft Tie-downs and Stop-blocks
Stud Extractor Tool V-blocks
Ezy Out Catch Basins (Fuel and Oil)
Wood or Plastic Spatula Permanent Marker
Tank Sprayer Strap Wrench

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 Lubricants, Sealants, and Adhesives
Chapter 3. Lubricants, Sealants, and Adhesives
3-1. Engine Oil Specifications
Lubricating oils qualified for use in Continental aviation gasoline (AvGas) engines are
required to meet Society of Automotive Engineers (SAE) specifications. SAE J1899 is the
specification for aircraft piston engine ashless-dispersant oil. SAE J1966 is the
specification for aircraft piston engine non-dispersant mineral oil.
Lubricating oil meeting these specifications is acceptable; proof of conformity is the
responsibility of the lubricant manufacturer.
Lubricating oil classified by North Atlantic Treaty Organization (NATO) or
Standardization Agreement (STANAG) as interchangeable with oils qualified under SAE
J1899 or SAE J1966 and assigned NATO codes O-123 or O-128 shall be considered
qualified.
The marketers listed in Table 3-1 have supplied data to Continental indicating the products
conform to one or more of the requirements above.
Continental recommended oil grades:
• Above 40°F ambient air, sea level SAE 50 or multi-viscosity
• Below 40°F ambient air, sea level SAE 30 or multi-viscosity

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Lubricants, Sealants, and Adhesives
Table 3-1. Qualified SAE J1899 Ashless Dispersant Engine Oil

Supplier Brand
Castrol Aviator AD Oil
Air BP Lubricants
Castrol Aviator A Oil
ExxonMobil Aviation Exxon Elite
NYCO S.A. Turbonycoil 3570
Pennzoil Company Pennzoil® Aircraft Engine Oil
Phillips 66 Type A 100 AD, 120 AD
Phillips 66 Aviation
Phillips 66 Victory Aviation Oil 100AW
ConocoPhillips
Phillips 66 X/C Aviation Oil SAE 20W-50, SAE 25W-60
Aeroshell Oil, (Mineral) 65, 80, 100, 2F Anti-Corrosion Formula
Aeroshell Multi-grade Oil AD, 15W - 50
Shell Aviation
Aeroshell Oil W65, W80, W100
Aeroshell Oil W80 Plus, W100 Plus Anti Corrosion Formula
Total Aero DM 15W - 50
Total Lubricants
Total Aero XPD 80 (SAE 40), XPD 100 (SAE 50), XPD 120 (SAE 60)

Table 3-2. Qualified SAE J1966 Non-Dispersant Mineral Oil

Supplier Brand
Phillips 66 Aviation Phillips 66 Type M Aviation Oil 20W-50 (Multi-viscosity)
ConocoPhillips Phillips 66 Type M Aviation Oil 100W (Grade 50)
Aeroshell Oil 65 (Grade 30)
Aeroshell Oil 80 (Grade 40)
Shell Aviation
Aeroshell Oil 100 (Grade 50)
Aeroshell Oil 120 (Grade 60)
Total Aero DM 15W - 50
Total Lubricants Total Aero 80 (SAE 40)
Total Aero 100 (SAE 50)

Table 3-3. Break-in Oil

Type Equivalent Application

SAE J1966 Aviation Non-dispersant mineral oil for piston
aircraft engines
First 25 hours of engine operation or
MIL-C-6529 Type II Corrosion until oil consumption stabilizes
Fly-away oil
preventive mineral oil
NOTE: Mineral oil conforming to MIL-C-6529 Type II contains a
corrosion preventive additive and must not be used for more than 25
hours or six months, whichever occurs first. If oil consumption has not
stabilized in this time, drain the mineral oil, replace the oil filter and
replace the discarded mineral oil with SAE J1966 aviation oil.
Table 3-4. Preservative Oil

Type Equivalent Application

Grade 1 Oil, Non-Rust VCI-105 Temporary or Indefinite Storage.
MIL-PRF-46002
Motorstor Engine Protectant Sprayed in cylinders (Section 9)

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3-2. Oil Change Intervals
Refer to the engine maintenance manual and/or the aircraft manufacturer’s or
Supplemental Type Certificate (STC) holder’s AFM/POH for oil specifications, specified
oil change intervals and inspection procedures.
Oil change intervals published in this manual are minimum requirements. Continental
believes more frequent oil and filter changes enhance engine service life. Drain and
replenish engine oil every 25 hours of operation or 4 months for engines that incorporate a
reusable oil screen. On engines with the full flow oil filters, large or small replaceable oil
filter cartridge, change the oil and filter every 50 hours and/or 4 months. Inspect oil screens
and oil filter elements for contaminates at each oil change. Oil analysis may be used in
addition to the oil screen or filter element inspection, but not as a replacement for it.
3-3. Additives
We often receive inquiries regarding the potential use of alternative fuel and oil additives
and/or concentrates (formulated primarily for automotive and industrial engine
applications) for use in our aircraft engines. Most of these additives and concentrates are
not compatible with air-cooled, light aircraft engines in their operating environments.
With the exception of the use of isopropyl alcohol or diethylene glycol monomethyl ether
(DiEGME) compound (described in the following paragraph), we do not recommend the
use of additives or concentrates in any of our aircraft engines. The use of unapproved
additives may void the engine warranty. Use only recommended fuels and lubricants.
WARNING
Mixing of the DiEGME compound with fuel concentration in
excess of the recommended (0.15 percent volume maximum)
could have a harmful effect on engine components. Use only the
manufacturer’s recommended blending equipment and
procedures to achieve proper proportioning.
Under certain ambient conditions of temperature and humidity, sufficient quantities of
water may exist in the fuel to create restrictive ice formation in the fuel supply. To
alleviate this occurrence, it is permitted to add no more than three percent Isopropyl
Alcohol to the fuel supply. Also, DiEGME conforming to military specification MIL-
DTL-85470B, if approved by the aircraft manufacturer, may be added for this purpose.
DiEGME compound must be carefully mixed with the fuel in concentrations not to exceed
0.15% (by volume).

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Table 3-5. Sealants
Continental
Part
Number Type Application Remarks
Non-beaded gaskets; Apply both sides
of starter gasket, oil cooler adapter
gasket, vacuum pump adapter gasket,
and fuel pump pad cover gasket. 0200D, X
Beaded gasket; Apply to non-beaded
side of starter gasket, oil cooler adapter
gasket, vacuum pump adapter gasket,
and fuel pump pad cover gasket.
All press type plugs (Hubbard etc.)
All models
Intake manifold gasket
ACC case to crankcase C-90, O200, IO240, O300,
(crankcase side only) IO360, LTSIO360, TSIO360
Oil drain back tubes C-90, O200, O300
Oil cooler (both sides) IO360, LTSIO360, TSIO360
CRC Copper Coat 401504 Oil seal accessory drive (O.D. only) IO360, LTSIO360, TSIO360
642188 Gasket Sealant
2 bolt suction tube gasket  470, 520 and 550 (where
(both sides) applicable)
470, 520, 550 (Sandcast), and
Gasket and oil filler neck holes GTSIO520
Cam bore cover gasket  470, 520, 550, GTSIO520,
(except beaded gasket) IO240
Idler pin gasket 470, 520, 550, GTSIO520
In parting line area of 3-way joints Sump to crankcase or sump to
crankcase to accessory case
All gaskets (both sides) except magneto
gasket and gaskets between intake
manifold and cylinder head. TIARA 6-285, 6-230
Oil seal at alternator drive 
(O.D. only)
All pipe thread fittings in fuel injection
646940 F/I Sealant Loctite 569 system (except pipe plug threads in See Figure 3-2
Hydraulic Sealant
throttle body units)
Crankcase parting face, between crkc All SI models
and sump gasket
Engine nose seal, scavenge oil pump
covers, between crankcase and sump All SI models (non-beaded
gaskets only)
Gasket Maker gasket, oil pump covers
646942 Loctite 515 Gasket Eliminator Between oil sump and sump gasket All SI models (non-beaded
Flange Sealant gaskets only)
642910 oil seal, O.D. of all uncoated oil
seals, except fuel pump adapter seal All SI models, where applicable
Between starter adapter gasket &
All Permold crankcase models
crankcase
649246 Loctite 290 Sealant Data plate screw installation on All models, where applicable
throttle bodies

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Table 3-5. Sealants
Continental
Part
Number Type Application Remarks
653692 Loctite LocQuic Primer 7649 Crankshaft nose oil seal area All models, where applicable
Crankcase parting face
Starter adapter to accessory case
Loctite 30516 Gasket Sealant Apply according to assembly
654663
(with P/N 641543 Silk Thread) Accessory drive adapter instructions
Pressure oil pump covers
Pressure scavenge pump covers
Use on all pipe threads except as noted
Loctite 567 Teflon PS/T Pipe elsewhere
Sealant. Option - Loctite Pipe All pressure relief valve housing threads All SI models, where applicable
Sealant With Teflon (PS/T) 592. Permold 2 studs engine mount 1-3-5
658769 Age Control Per MHS-223, Affix side bottom
Expiration Date On Each Tube. All threaded fasteners installed in a stud Apply before installing threaded
hole through to an oil source fastener
Option - P/N 657042, Loctite Use on all pipe threads to oil coolers All models (use sparingly on
565 Adhesive Sealant and other oil sources male threads only)
Ignition harness terminals at magneto
N/A Miller-Stephenson MS-122AD block end & spark plug / ECU terminals All models, where applicable

Table 3-6. Lubricants

Continental
Part Type Application Remarks
Number
Fuel injector nozzles 
(at cylinder head) See Figure 3-1
Mechanical tachometer drive housing
threads not connected through to an oil At engine assembly
source.
Exhaust studs (applied to nut end
646943 Loctite 76732 (646943) before torque), exhaust slip joints
All except TSIOL550
Loctite 1999141 (646943-1)
646943-1 Anti-Seize Lubricant Vernatherm plug
All 0.3125 and larger studs unless At engine assembly
otherwise noted
Throttle body air reference fittings Where applicable
Oil sump return fitting IO360ES3B, 14B;
IO360HB9B
Fuel injection linkages At engine assembly
654468 Shell #5 MIL-G-3545-C Grease Apply at pivot points during
Throttle & mixture control linkages assembly and periodic
maintenance
654514 CRC 336 Rust Preventative Spray exhaust end of turbocharger After engine test
Compound
LTSIO360E, EB, RB;
Apply to oil seal lip only (alternator seal) TSIO360E, EB, F, FB, GB, KB,
654561 Shell Gadus S2 V220 2 LB
Apply to crankshaft nose oil seal lip All models, where applicable

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Table 3-6. Lubricants
Continental
Part Type Application Remarks
Number
Starter worm gear & bevel gear teeth
All models during engine
Needle bearings and ball bearings
assembly
Valve stems
Accessory drive splines and couplings Where applicable
Idler gear and pin 470, 520, 550
Magneto rubber drive bushings
656817 Super Molyshield Grease All models
Oil seal lips only
Except 360, TSIO520D, 
Fuel injection controls, o-rings, springs, GTSIO520K, which use 50W
shafts, and bushings
motor oil
Coat gear cavity during pump
Oil pumps (pressure & scavenge)
assembly
Adapter (tach reduction) TSIO & LTSIO360
Use only manufacturer’s
N/A recommended spark plug Spark plugs
thread lubricant
All models
Chesterton #995 Release Induction system hoses and flex duct
N/A Agent connections, pipe plugs in throttle body
or WD-40 units
Rubber oil seal of spin-on oil filters. Do
not apply to oil filter P/N 658753,
658754, or 658755 filters with anti-stick
N/A Dow Corning No. 4 coating on seal. All models where applicable
Governor pad gaskets (both sides)
Starter adapter cover o-rings
N/A Dow Corning G-N Paste Camshaft lobes and tappet faces During engine assembly
N/A LPS 2 Throttle and Mixture Control Valves Apply at pivot points during
Linkages maintenance
N/A LPS Procyon or LPS 3 Flanged Nut (P/N 652541) at Cylinder Apply after inspection
Base
N/A Lubriplate 630 AA (optional) Throttle and Mixture Control Valves Apply at pivot points during
Linkages assembly
N/A Lubriplate 930 AA O.D. of valve guides All models during valve guide
installation
Carbon solvent used on
N/A Mouse Milk Wastegate butterfly and linkage turbocharged engines during
preventive maintenance

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Table 3-6. Lubricants
Continental
Part Type Application Remarks
Number
Quill shaft springs GTSIO520
Crankshaft bearings
Connecting rod bearings
Prop driver, driven gears & bearings
Camshaft bearings
Tachometer gears & adapters During engine assembly
Accessory spur gear teeth
Prop governor transfer collar & sleeve
Starter cone, bushing & nut
Starter clutch spring (ID & OD)
Pistons, piston pins, & piston rings
SAE J1966 Grade 50  Thrust washers
N/A During engine assembly
Aviation Oil Oil filter adapter seals
O-rings (unless otherwise specified)
Carburetor fuel connections Carburetor-equipped models
Valve guide seals Apply to sealing surface
V.T.C. unit pistons & centrifugal valves,
rocker arms, valves and tappets TIARA 6-285, 6-230
Cylinder studs, through bolts,
crankcase studs, connecting rod bolts
and nuts; and engine accessory studs Lubricate bolt thread and nut
unless installed in blind or stud holes seat before tightening nuts
not through to an oil supply or otherwise
specified
Cylinder exhaust port flange studs TSIOL550 ONLY

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Table 3-7. Adhesives
Continental
Part
Number Type Application Remarks
Cylinder deck studs Breakaway torque minimum
100 in-lbs. after two hours
470 & 520 (Sandcast) &
Crankcase breather tubes GTSIO520
Crankcase nose seal retainer bolts All models
Intake manifold mount studs C-75, C-85, C-90 & O-200
Mechanical tachometer drive studs
Where applicable
trough to an oil source
Loctite 271 High Strength IO360, LTSIO360, TSIO360,
646941 Adhesive Sealant O470, IO470, TSIO470,
(used with P/N 653693 Oil gauge rod housing to crankcase IO520A, B, E, G, J, K, L,
Loctite 7471 Primer) IO550D, E, F, TSIO520A, AE,
AF, C, CE, G, H, M, P, R, T
Oil pump gear mounting pin in
accessory cover IO360, LTSIO360, TSIO360

Press fit breather and oil fill necks IO240, IO360, LTSIO360,
TSIO360
Rocker cover studs, rocker arm pivot
studs, push rod retainer stud TIARA 6-285, 6-230
Timing indicator pin GTSIO-520
Top accessory drive gear (breather
slinger) bolts
TIARA 6-285, 6-230
V.T.C. unit bushing retainer screws
V.T.C. unit housing to crankshaft
Solenoid Valve assembly (bracket to Engines with priming system
valve) solenoid valves, as applicable
Manifold valve to bracket screws All models
Coolant pump impeller ring screws All liquid cooled models
Studs 0.25 diameter and smaller
649306 Loctite 222 Sealant (do not use on cylinder exhaust port All models
(optional (or optional Loctite Hydraulic flange)
646940) Sealant 569)
Mag stud holes and stud holes through 0200, IO240, 0300, IO360,
LTSIO360, TSIO360, 470, 520,
an oil source on accessory end of 550 (apply when installing
crankcase
studs)
All pipe thread fittings in fuel injection
system except pipe plug threads in All models
throttle body unit
Magneto housing pressurization fitting
658517
(optional Loctite 243 Bolts for nose seal retainer to All models, where applicable
(optional Loctite 242) crankcase
649366) Starter adapter - all stud locations
Coolant pump mechanical seal,
652983 Loctite 620 Adhesive Sealant standard repair on starter adapter All liquid cooled models
bearing bore

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Table 3-7. Adhesives
Continental
Part
Number Type Application Remarks
O200, O300, IO240, 0470,
654495 Loctite 8531 Adhesive Sealant Starter clutch assembly bearing IO470, IO520, L/TSIO520,
IO550, TSIOL550
Bearing OD installed on starter clutch
654562 Loctite 609 Adhesive / Sealant assembly O200A, B, IO240A, B, O300A
GIO550, GTSIO520, IO520,
655515 Adhesive Sealant (RTV) Alternator assembly IO550, IOF550, TSIOL550,
TSIOF550
I0360AF, ES;
TSI0360MB,RB,SB;
Induction Manifold (Felt to Manifold) LTSI0360RB; I0550G,N,P,R;
I0F550; TSI0520BE; TSI0550;
TSI0F550D,J,K,P;
655700 PBC30 Adhesive IO550G,N,P,R; IOF550N, P, R;
Cylinder Baffle (Grommet to Baffle
658503) TSI0520BE; TSI0550;
TSI0F550;
Baffle Assembly-Oil Cooler (Seal to Baffle
TSI0550K,N
658064)
Bracket-Injection Lines (Bumper To I0550R
3M Scotch-Weld 1300 Bracket 658514)
658493
Adhesive Diverter Valve Bracket (Bumper To
Bracket 656225) I0F550B,C,D,E,F,L
All FADEC (apply to gasket
EMI Gasket
before installing on ECU)
800126 3M Super 77 Adhesive
Cylinder Baffle (Rubber Isolator To 0200D
Cylinder Baffle 657488)

Table 3-8. Miscellaneous

P/N Type Application Remarks

Safety wire -.032 in dia. Steel
535011 Corrosion Resistant Where safety wire is required N/A
Safety wire -.020 in dia. Steel
800154 Where safety wire is required FADEC electronic control units
Corrosion Resistant
626531-1 Enamel - Gold (1 qt) High temperature paint for cosmetic and N/A
corrosion protection
626531-3 Enamel - Gold (1 gal)
High temperature paint for cosmetic and
626531-6 Enamel - Platinum corrosion protection Platinum models only
High temperature paint for cosmetic and
626531-7 Enamel - Black Cylinder barrels
corrosion protection
626531-9 Enamel - Black Gloss  1 gallon enamel and 1/2 gallon catalyst Rocker covers, as required
w/catalyst (1 gal)
“ACCELAGOLD” Corrosion protection interior and
N/A Turco Products exterior aluminum parts N/A

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Table 3-8. Miscellaneous

P/N Type Application Remarks

658555-1 Primer, Zinc Phosphate (Armor Cylinders (through hardened cylinder All Models (w/through hardened
Tech Epoxy Ester Primer) barrel touch-up only) cylinder barrels)
Valve Face to Valve Seat inspection
--- Permatex 8003B Prussian Blue (during valve lapping) N/A

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3-3.1. General Sealant Application Instructions
CAUTION: Never apply anti-seize lubricant to the first two threads
to prevent contaminating fuel supply. Only apply to fitting tapered
ends up to the first two threads.
CAUTION: Never use Teflon® tape on fluid fittings or fuel injector
nozzles. Reference Table 3-5, “Sealants”.

Figure 3-1. Anti-Seize Lubricant Application

CAUTION: Apply P/N 646940, (Loctite 569) fuel injection (F/I)

sealant to the tapered threads of the fitting only (ref. Table 3-5).
Never use Teflon tape on fluid fittings or fuel injector nozzles.

Figure 3-2. Fuel Injection Sealant Application

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3-3.1.1. Four Cylinder Engine Crankcase Threading
WARNING
Do not apply any form of sealant to the crankcase cylinder
deck, chamfer, cylinder mounting flange, cylinder base O-ring,
or cylinder fastener threads. The use of RTV, silicone, Gasket
Maker or any other sealant on the areas listed above during
engine assembly will cause a loss of cylinder deck stud or
through-bolt torque. Subsequent loss of cylinder attachment
load, loss of main bearing crush and/or fretting of the
crankcase parting surfaces will occur. The result will be
cylinder separation, main bearing movement, oil starvation and
catastrophic engine failure. USE ONLY CLEAN 50 WEIGHT
AVIATION ENGINE OIL ON SURFACES LISTED.
1. Use full strength, non-thinned P/N 654663 (gasket sealant). Shake or mix well
before using.
CAUTION: Apply gasket sealant and threading (a continuous, single
piece) only as illustrated. Do not apply gasket sealant to crankshaft
nose seal area.
2. Apply P/N 654663 (gasket sealant) to 2-4 case half according to the manufacturer’s
instructions only in areas where threading is indicated. When applying, use short
light brush strokes until an even thin coat is obtained. The gasket sealant should be
viscous enough that most of the brush marks disappear; if not, discard the old gasket
sealant and reapply with new gasket sealant.
NOTE: Allow the gasket sealant to air dry to a tacky condition before
applying silk threading.
3. Apply a thin translucent coat of P/N 646942 (gasket maker), not to exceed 0.010
inch thick, to the 1-3 case half. Apply gasket maker in all areas that will mate against
areas where gasket sealant was applied on the matching 2-4 case half (except the
through bolt bosses).
4. Apply and position P/N 641543 (a continuous, single piece of grade “D” silk thread)
on the 2-4 case half as specified (see Figure 3-3 or Figure 3-4). Ensure the free ends
of the thread will be covered by gasket material (except at the nose oil seal).
5. Assemble crankcase halves; install and torque all crankcase hardware in proper
sequence in accordance with the applicable overhaul manual as soon as possible.
NOTE: Take care to prevent displacement or damage to the crankshaft oil
seal and silk thread. Ensure thrust washer halves and bearing halves
remain in place.
6. After crankcase torque, follow the instructions in Section 10-10 to install the nose
oil seal.

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Figure 3-3. Crankcase Threading Diagram - C75, C85, C90, O200

Figure 3-4. Crankcase Threading Diagram - O240, IO240, IOF240

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3-3.1.2. Six Cylinder Engine Crankcase Threading
WARNING
Do not apply any form of sealant to the crankcase cylinder
deck, chamfer, cylinder mounting flange, cylinder base O-ring,
or cylinder fastener threads. The use of RTV, silicone, Gasket
Maker or any other sealant on the areas listed above during
engine assembly will cause a loss of cylinder deck stud or
through-bolt torque. Subsequent loss of cylinder attachment
load, loss of main bearing crush and/or fretting of the
crankcase parting surfaces will occur. The result will be
cylinder separation, main bearing movement, oil starvation and
catastrophic engine failure. USE ONLY CLEAN 50 WEIGHT
AVIATION ENGINE OIL ON SURFACES LISTED.
1. Use full strength, non-thinned P/N 654663 (gasket sealant). Shake or mix well
before using.
CAUTION: Apply gasket sealant and threading (a continuous, single
piece) only as illustrated.
2. Apply P/N 654663 (gasket sealant) to 2-4-6 case half according to the
manufacturer’s instructions only in areas where threading is indicated. When
applying, use short light brush strokes until an even thin coat is obtained. The gasket
sealant should be viscous enough that most of the brush marks disappear; if not,
discard the old gasket sealant and reapply with new gasket sealant.
NOTE: Allow the gasket sealant to air dry to a tacky condition before
applying silk threading.
3. Apply a thin translucent coat of P/N 646942 (gasket maker), not to exceed 0.010
inch thick, to the 1-3-5 case half. Apply gasket maker in all areas that will mate
against areas where gasket sealant was applied on the matching 2-4-6 case half
(except the through bolt bosses).
4. Apply and position P/N 641543 (a continuous, single piece of grade “D” silk thread)
on the 2-4-6 case half as specified (see Figure 3-6 through Figure 3-9). Ensure the
free ends of the thread will be covered by gasket material (except at the nose oil
seal).
5. Assemble crankcase halves; install and torque all crankcase hardware in proper
sequence in accordance with the applicable overhaul manual as soon as possible.
NOTE: Take care to prevent displacement or damage to the crankshaft oil
seal and silk thread. Ensure thrust washer halves and bearing halves
remain in place.
6. After crankcase torque, follow the instructions in Section 10-10 to install the nose
oil seal.

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Figure 3-5. Crankcase Threading Diagram - O300

Figure 3-6. Crankcase Threading Diagram - IO360, L/TSIO360

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Figure 3-7. Crankcase Threading Diagram - 520/550 Permold

Figure 3-8. Crankcase Threading Diagram - 470/520/550 Sandcast

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Figure 3-9. Crankcase Threading Diagram - GTSIO520

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3-3.2. Scavenge Pump Body Sealant and Threading
1. Use full strength, non-thinned P/N 654663 (gasket sealant). Shake or mix well
before using.
NOTE: Apply gasket sealant and threading (a continuous, single piece)
only as illustrated.
2. Apply P/N 654663 (gasket sealant) to scavenge pump body according to the
manufacturer’s instructions only in areas where threading is indicated. When
applying, use short light brush strokes until an even thin coat is obtained. The gasket
sealant should be viscous enough that most of the brush marks disappear; if not,
discard the old gasket sealant and reapply with new gasket sealant.
NOTE: Allow the gasket sealant to air dry to a tacky condition before
applying silk threading.
3. Apply a thin translucent coat of P/N 646942 (gasket maker), not to exceed 0.010
inch thick, to areas of the starter adapter cover where gasket sealant was applied on
the mating surfaces.
4. Apply and position P/N 641543 (a continuous, single piece of grade “D” silk thread)
as shown by the dashed lines in Figure 3-10.
5. Assemble and torque as soon as possible in accordance with the applicable overhaul
manual.

Figure 3-10. Scavenge Pump Body Threading Diagram

Applicable to scavenge pump bodies, Part Nos. 640741, 652019, 655713,
used on starter adapters 642087 & corresponding 0.015 oversize adapters

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3-3.3. Oil Pump Assembly Sealant and Threading
1. Use full strength, non-thinned P/N 654663 (gasket sealant). Shake or mix well
before using.
NOTE: Apply gasket sealant and threading (a continuous, single piece)
only as illustrated.
2. Apply P/N 654663 (gasket sealant) to the oil pump housing according to the
manufacturer’s instructions only in areas where threading is indicated. When
applying, use short light brush strokes until an even thin coat is obtained. The gasket
sealant should be viscous enough that most of the brush marks disappear; if not,
discard the old gasket sealant and reapply with new gasket sealant.
NOTE: Allow gasket sealant to air dry to a tacky condition before
applying silk threading.
3. Apply a thin translucent coat of P/N 646942 (gasket maker), not to exceed 0.010
inch thick, to areas of the oil pump cover where gasket sealant was applied on the
mating surfaces.
4. Apply and position P/N 641543 (a continuous, single piece of grade “D” silk thread)
as shown by the dashed lines in Figure 3-11 through Figure 3-15.
5. Assemble and torque as soon as possible according to the overhaul manual
instructions.

Figure 3-11. Oil Pump Assembly Threading Diagram

Applicable to oil pump assembly, Part Nos. 631713, 632481, 632563, & 641993

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Figure 3-12. Oil Pump Assembly Threading Diagram

Applicable to oil pump assembly, Part No. 632623

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Figure 3-13. Oil Pump Assembly Threading Diagram

Applicable to oil pump assembly,
Part Nos. 646194, 653536, 655121, & 643527

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Figure 3-14. Oil Pump Assembly Threading Diagram

Applicable to oil pump assembly, Part Nos. 643716, 643717, 643743, 643778, 643779, 653494,
653538, 653542, 653542, 653553, 655117, 655119, 655123, 655124, & 655127

Figure 3-15. Oil Pump Assembly Threading Diagram

Applicable to oil pump assembly,
Part Nos. 631149, 632970, 632977, 654437, 655349, & 655680

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3-3.4. Starter Adapter Assembly Sealant and Threading
1. Use full strength, non-thinned P/N 654663 (gasket sealant). Shake or mix well
before using.
NOTE: Apply gasket sealant and threading (a continuous, single piece)
only as illustrated.
2. Apply P/N 654663 (gasket sealant) to the starter adapter housing according to the
manufacturer’s instructions only in areas where threading is indicated. When
applying, use short light brush strokes until an thin, even coat is obtained. The
gasket sealant should be viscous enough that most of the brush marks disappear; if
not, discard the old gasket sealant and reapply with new gasket sealant.
NOTE: Allow gasket sealant to air dry to a tacky condition before
applying silk threading.
3. Apply and position P/N 641543 (a continuous, single piece of grade “D” silk thread)
as shown by the dashed lines in Figure 3-16.
4. Temporarily install the starter adapter to make an impression of the silk thread on
the accessory case.
5. Carefully remove the starter adapter so that the shaft gear does not pull out.

Figure 3-16. Starter Adapter Assembly Threading Diagram

Applicable to starter adapter assembly,
Part Nos. 641348, 646220, & 653074
6. Inspect the thread impression for 100% contact between the starter adapter housing
and accessory case.

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7. Apply a thin translucent coat of P/N 646942 (gasket maker), not to exceed 0.010
inch thick, to areas of the accessory case that mate with the gasket sealant on the
starter adapter housing.
8. Install and torque the starter adapter according to the instructions in the applicable
overhaul manual as soon as possible.
9. Wipe excess sealant from the accessory case and starter adapter.
3-3.5. Starter Adapter Accessory Drive Cover Sealant and Threading
1. Use full strength, non-thinned P/N 654663 (gasket sealant). Shake or mix well
before using.
NOTE: Apply gasket sealant and threading (a continuous, single piece)
only as illustrated.
2. Apply P/N 654663 (gasket sealant) to 2-4-6 case half. Apply gasket sealant per the
manufacturer’s instructions only in areas where threading is indicated. When
applying, use short light brush strokes until an even thin coat is obtained. The gasket
sealant should be viscous enough that most of the brush marks disappear; if not,
remove old gasket sealant and reapply with new gasket sealant.
NOTE: Allow gasket sealant to air dry to a tacky condition before
applying silk threading.
3. Apply a thin translucent coat of P/N 646942 (gasket maker), not to exceed 0.010
inch thick, to the mating area of the accessory drive cover.
4. Apply and position P/N 641543 (a continuous, single piece of grade “D” silk thread)
as shown by the dashed lines in Figure 3-17.
5. Assemble and torque as soon as possible according to the overhaul manual
instructions.

Figure 3-17. Accessory Drive Cover Threading Diagram

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 Airworthiness Limitation Section

Chapter 4. Airworthiness Limitation Section

Each aircraft engine certified under Title 14 Code of Federal Regulations (CFR), § 33
Amendment 9 or later requires an Airworthiness Limitation Section in the principal
(primary) Instructions for Continued Airworthiness that is segregated and clearly
distinguishable from the rest of the manual. Consult Section 1-1.1 of this manual to
determine the part number of the primary ICA for your engine.
Continental engine Instructions for Continued Airworthiness with an initial publication
date later than 1984 contain an Airworthiness Limitation Section.
Continental piston aircraft engines certified under CAR 13 or prior to 14CFR § 33
Amendment 9 predate the Airworthiness Limitation Section requirement; consult the
latest revision of Continental SIL97-1 for information regarding engine Instructions for
Continued Airworthiness that do not contain an Airworthiness Limitation Section.

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Airworthiness Limitation Section

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 Engine Removal & Installation
Chapter 5.Engine Removal & Installation
5-1. Engine Removal
5-1.1. Tools and Consumable Supplies
WARNING
Ensure engine hoist and slings are designed to support the
weight of the total engine weight, including accessories.

Use of engine lifting eyes to lift the aircraft is strictly
prohibited.
CAUTION: Keep crankshaft axis horizontal during handling
operations.
1. Engine Hoist (rated for 800 lbs. minimum)
2. Two (2) engine slings (rated for 800 lbs. minimum)
3. Engine Transport Stand
4. Catch Basins (oil and fuel)
5. Tank Sprayer with Stoddard Solvent (exterior engine cleaning)
5-1.2. Engine Removal Procedure
Reference the principal ICA (Section 1-1.1) for the engine being installed for removal
procedures.

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Engine Removal & Installation
5-2. Engine Installation
5-2.1. Common Tools and Consumable Supplies
WARNING
Ensure engine hoist and slings are designed to support the
weight of the total engine weight, including accessories.

Keep crankshaft axis horizontal during handling operations.
1. Engine Hoist (rated for 800 lbs. minimum)
2. Two (2) engine slings (rated for 800 lbs. minimum)
3. Oil conforming to SAE J1966 (break-in oil, non-dispersant mineral oil) MIL-C-
6529 Type II (Fly-away oil)
4. Ashless dispersant oil conforming to SAE J1899
5. MIL-PRF-46002, Grade 1 oil
6. Approved fuel for the engine model (see Section 7-2.2) or Type Certificate Data
Sheet (TCDS)
7. Spark plugs and copper gaskets
8. MS20995 Type A Safety Wire (0.020” and 0.032”)
9. Cable ties or nylon lacing cord
10. Bladder-type pressure pot (at least 1 gallon capacity)
11. Type 1 flammable fuel container (at least one gallon capacity)
12. Clean fuel hoses (fuel system setup)
13. AN union fittings (fuel system setup)
14. Rubber grommets (bulkhead and baffle pass-through)
15. MS-122AD Spray (procured from Miller-Stephenson)
16. Spark Plug Manufacturer’s recommended spark plug thread lubricant
17. Continental P/N 646940, Hydraulic Sealant
18. Continental P/N 646943, Anti-seize Lubricant
19. Continental P/N 658769, PS/T Pipe Sealant
20. Other supplies required by the aircraft manufacturer’s instructions.

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 Engine Removal & Installation
5-2.2. Engine Receipt and Handling
When the engine arrives, inspect the crating for damage. If the engine crating appears
damaged, notify the freight shipping company for resolution. If the crating appears intact,
proceed to Section 5-2.3.
5-2.3. Uncrating the Engine
1. Remove the lag screws attaching the wooden cover to the base.
2. Lift the wooden cover and remove it.
3. Open the plastic bag wrapped around the engine.
4. Inspect the engine according to the “Acceptance Inspection” criteria in Section 5-
2.5.
NOTE: The engine is preserved for long term storage at the factory; if it is
not immediately installed after acceptance, refer to the “Engine
Preservation and Storage” instructions in Chapter 9 for ongoing corrosion
protection instructions. Environmental conditions (humidity), seasonal
changes, and engine usage influence susceptibility to corrosion. In areas
of high humidity, corrosion can occur within two days of uncrating the
engine. The owner/operator is responsible for recognizing the risk of
corrosion and taking the appropriate precautions.
5. If the engine will be stored for any length of time, refer to the “Engine Preservation
and Storage” instructions in Section 9.
5-2.4. Crating an Engine for Shipping
1. Lower the engine onto the container base.
2. Attach the engine using shock mounts and bolts.
3. Cover the engine with a plastic bag.
4. Install and attach the container cover to the base.
5-2.5. Acceptance Inspection
CAUTION: If hidden engine damage or corrosion is discovered,
contact Continental (see “Contact Information” in Section 1-3). Do
not install or place a damaged/corroded engine in storage.
1. Verify the engine serial number and model number on the engine nameplate are the
same as specified in the engine logbook and the packing slip.
2. Inspect the engine for signs of damage or corrosion.
a. If the engine exhibits no sign of damage or corrosion, proceed with installation.
b. If damage or corrosion is discovered, contact the supplier of the engine for
disposition.

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Engine Removal & Installation
5-2.6. Engine Transport
Refer to the “Engine Installation Drawings” in the primary ICA (Section 1-1.1) for lifting
eye locations.
CAUTION: Do not allow chains to become entangled on the engine
or its hardware. Ensure the area is clear when lifting the engine. Do
not allow the front, rear, sides or bottom of the engine to strike any
obstructions as the extreme weight may damage the engine or its
components.
1. Attach a hoist to the engine lifting eyes located at the top of the crankcase backbone.
2. Take up slack on the hoist prior to loosening the engine mount bolts; remove the
bolts from the shipping shock mounts.
3. Lift the engine and install it on a transportation stand or dolly.
5-2.7. Engine Installation Procedures
Refer to the engine installation instructions in the primary ICA for the engine being
installed when installing a like engine as a replacement. For engines being installed for the
first time in a new aircraft, refer to the engine installation manual.
NOTE: The installer is authorized to reposition engine component fittings,
if necessary, to mate with the aircraft interfaces, See Section 5-2.8.

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 Engine Removal & Installation
5-2.8. Engine Adjustments and Component Replacement by OEMs and STC
Converters
Continental supplies engines to aircraft Original Equipment Manufacturer’s (OEM) and
STC Converters. These engines have been assembled, tested and inspected in accordance
with Continental FAA approved quality system standards and FAA issued Production
Certificate.
NOTE: Fitting orientation is determined at the time engine model
specification is designated for the aircraft application. If fitting
orientation adjustment is required for every engine installation, a model
specification change request may be more appropriate than repeated
repositioning of fittings.
Normally, only minor adjustments to the engine fuel system will be necessary at engine
installation (Reference Section 6-4.7, “Engine Operational Check”). Occasionally, minor
adjustment may be necessary to other engine systems, components, or to position fittings
for best routing and fit.
Continental hereby authorizes the specified adjustment and component replacements
listed in Table 5-1 to OEM and STC Converters who are approved by the FAA as an
aircraft production facility or FAA Approved modification facility.
Personnel performing the specified adjustment and component replacements must be a
licensed Airframe and Power Plant mechanic or be approved by the OEM or STC
Converter facilities quality assurance to be capable of performing the specific task. Work
shall be performed in accordance with applicable continued airworthiness instructions
including but not limited to the engine Installation Manual, Maintenance and Overhaul (or
Overhaul) Manual, Service Documents.
All work performed in accordance with these instructions must be documented by the
individual performing the task on the OEM or STC Converters FAA approved Quality
Inspection Document and traceable by engine and/or aircraft serial numbers.
Adjustments and/or replacements accomplished in accordance with these instructions
must be documented by the OEM on the aircraft production paper work. Additionally, the
OEM must provide Continental notification of adjustments and replacements
accomplished in accordance with these instructions. If a component part is replaced, the
OEM must provide the part number and serial number of the component removed and the
part number and serial number of the component installed. Return of any removed
component is to be coordinated with Continental via the OEM/Converter Customer Portal.

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Engine Removal & Installation
Table 5-1. Authorized Adjustments and Replacements
Authorized Adjustments Authorized Replacements
Accessory Drive Belts Alternator
Baffles and Baffle Seals Baffles

Engine Control Cable Support Brackets and Carburetor and/or Carburetor Airbox
Attachment Points Crankshaft/Propeller Shaft Nose Oil Seal
Fluid Lines and Hoses, Attachment and Support Engine Mount Legs
Fuel Pump, Throttle & Fuel Control Unit Fittings Exhaust System Components
• Fuel Drain Fitting(s) Fuel Injector Nozzles
• Fuel Inlet Fitting Fuel Injection Lines and Hoses
• Fuel Return Fittings Ignition Harness
• Fuel Vapor Return Fittings Manifold Valve
Fuel System Adjustment Magnetos
Induction System Hose Clamps Magneto Sensor(s)
Magneto Orientation (positioning) Oil Coolers and adapter plates
Magneto Timing to Engine Oil Filters
Oil Supply and Return Fittings Oil Screens
Reference Air Fittings Oil Pump
Worm Screw Clamps Oil Sump and Gasket
Spark Plugs
Starter Adapter Assembly
Starter Motor
Turbocharger and Turbocharger System
Components

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 Engine Removal & Installation
5-2.9. Engine Pre-oiling
WARNING
Do not use the starter to rotate the engine during engine pre-
oiling. Persistent engagement of the starter to rotate the
crankshaft will exceed the starter duty cycle and may result in
premature starter failure.
1. Install and torque the spark plugs and ignition lead wires according to the “Ignition
System Maintenance” instructions in Section 6-4.9.
2. Verify lubrication lines, fittings, hoses, screens, and filters are in place prior to pre-
oiling.
3. Obtain a 1-gallon capacity bladder-type pressure pot with an output pressure of 50
psi (not to exceed 60 psi).
4. Connect the pre-oiler supply hose to the engine oil pressure output (fitting). It may
be necessary to disconnect the aircraft oil pressure sensor fitting according to the
aircraft manufacturer's instructions.
5. Remove the rocker covers.
6. Open the pre-oiler valve and monitor the rocker arms for oil flow. Depending upon
oil temperature, it may take several minutes to see an indication of oil flow.
7. Close the pre-oiler valve upon verification of oil flow at the rocker arms.
8. Install the rocker covers with new gaskets according to the “Cylinder Installation”
instructions in the primary ICA (Section 1-1.1). Torque the rocker cover fasteners to
Appendix B specifications.
9. Disconnect the pre-oiler supply hose and cap; connect the aircraft oil pressure sensor
to the engine oil pressure output according to the aircraft manufacturer's
instructions.
WARNING
Do not operate the engine unless the oil is properly serviced.
10. Check the oil level in the sump using the oil gauge rod (dip stick). Verify the engine
oil is at the proper level according to instructions in the primary ICA (Section 1-1.1)
for the engine model.

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 Engine Inspection and Service
Chapter 6. Engine Inspection and Service
6-1. Engine Inspection Introduction
Inspections described in this chapter apply only to the Continental engines covered by this
manual. Perform the engine inspections according to the instructions provided. Perform
aircraft inspections according to the aircraft manufacturer's instructions. Refer to the
following sections:
• Section 6-2, “Inspection and Maintenance Schedule”
• Section 6-3, “Time Between Overhaul”
• Section 6-4, “Scheduled Inspections”
• Section 6-5, “Unscheduled Maintenance”
• Section 6-6, “Inspection Checklists”
Some inspections are at predetermined intervals (scheduled) while others are based on
circumstance (unscheduled). Engine servicing is performed at scheduled intervals but may
also be performed “on condition.” The first part of this chapter is devoted to scheduled
maintenance intervals and associated procedures; unscheduled maintenance instructions
follow the scheduled maintenance instructions.
NOTE: Discrepancies discovered by the person conducting the scheduled
or unscheduled inspections, even if the discrepancy is not an itemized
inspection item, should be corrected upon discovery. Fuel and oil system
contamination affects engine performance and service life. If oil or fuel
system contamination is discovered, do not limit the correction to the
symptom; isolate and correct the source of the contamination, including
any residual material left in the engine by the source of the contamination.
6-2. Inspection and Maintenance Schedule
Unless another FAA-approved Inspection Program is established, the Engine Inspection
and Maintenance Schedule shows the inspections for the subject engines covered by this
manual in their original type design. The inspections described in this chapter apply to the
engine and not to the aircraft. Refer to the Aircraft Manufacturer’s manual for airframe
inspection requirements.
The inspections are progressive; commencing from the date the engine is placed in
service. The inspection intervals are tracked by Engine Log entries and designated by
hours of operation or calendar time, whichever occurs first. Inspection techniques must be
executed consistently for reliability.
6-3. Time Between Overhaul
Continental provides operational limitations and instructions for your engine along with the
requirements for continued airworthiness as specified in the engine Operator Manuals,
Maintenance Manuals, Overhaul Manuals, and Service Documents. The Time Between
Engine Overhaul provided in this document applies only to engines that have been operated
and maintained in accordance with these instructions. Engine mounted components and
accessories require overhaul at the same hourly and calendar intervals as the engine, unless
otherwise specified by the component or accessory manufacturer.

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Engine Inspection and Service
An engine’s published TBO DOES NOT mean that every engine will operate the number
of hours or years listed without requiring component replacements and/or unscheduled
maintenance events. Noncompliance with Continental instructions for continued
airworthiness, operational and/or environmental factors may necessitate repair or
replacement of the engine, engine components and accessories earlier than the published
TBO.
TBO periods were established on most Continental engines beginning in the 1960s. Since
that time, Continental has made significant engineering improvements to virtually all
major engine components. Continental has refined manufacturing processes and
implemented computer numerical controlled (CNC) machining tools enabling Continental
factory engines to meet higher standards than possible when the engines were originally
granted FAA Type Certificates. These improvements have enabled Continental to increase
TBO limits for many of our new and rebuilt engines.
Continental recommends the following factors be used, along with the engine’s published
TBO, to determine the engine’s continued airworthiness:
1. Environmental corrosion occurs internally and externally on an engine. This
naturally occurring process can affect continued airworthiness of the engine and
engine mounted components or accessories. Regardless if the engine has been
operated regularly or has been in storage; gaskets, seals, and synthetic and natural
rubber goods deteriorate over time. Replace or overhaul the engine upon
accumulating the operating hours specified in Table 6-1, or twelve (12) years after
being placed in service, whichever occurs first.
2. For engines used in aerial spraying, TBO is 1200 hours or twelve (12) years
whichever occurs first.
3. Engines used in parachute jumping, glider towing, banner towing, blimp propulsion,
or other unusually stressful applications may require more frequent overhauls than
listed.
4. The quality of parts, accessories and workmanship utilized during routine
maintenance, engine top overhaul and major overhaul has a direct effect on the
service life of the engine. Also, the maintenance and condition of engine-related
components - including, but not limited to, propeller, propeller governor, vacuum
pump, gear driven alternator, mount, baffles, instrumentation, and controls has a
direct effect on engine durability. The TBO periods listed are predicated on the
engine having been maintained according to the Instructions for Continued
Airworthiness, (ICA) accepted by the FAA, specified in the engine Maintenance
Manual, Overhaul Manual, and Service Documents, and operated within the
limitations published in the engine operating instructions or the aircraft
manufacturer’s Aircraft Flight Manual / Pilot’s Operating Handbook (AFM / POH).
5. Continental does not provide a TBO for engines that have been:
• Assembled with parts not supplied by Continental
• Assembled with parts that do not conform to the original FAA approved type
design for the engine

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 Engine Inspection and Service
• Modified from the original type certificate configuration
• Overhauled or repaired in a manner that is inconsistent with the specifications,
limits, and instructions provided in the Continental Instructions for Continued
Airworthiness and FAA Airworthiness Directives
6. The “Hobbs Meter” is commonly used by the aviation industry as an acceptable
device to record time elapsed while electrical power is applied to the device. The
conditions under which the Hobbs Meter records operation vary widely within the
aviation industry. Continental does not specify a method to record engine operating
hours, rather, Continental defers to the end application installer.
NOTE: TBO periods specified in this document are only estimates and do
not reflect warranty periods. For engine warranty coverage, refer to the
original Aircraft Engine Warranty received with the engine.
Table 6-1. Engine Time Between Overhaul (TBO)
HOURS/YEARS
ENGINE ENGINE
S/N BEFORE S/N 1006000
ENGINE MODEL SEE NOTE 1006000 AND LATER
A65, A75 and C75, C85, C90 Series 1 1800/12
O-200-A, B 1, 2 1800/12 2000/12
O-200-D 1

1, 2 2000/12 2200/12
IO-240-A, B
1, 2
IOF-240-B
1 1500/12
IO-346-A
1 1800/12
C125, C145 Series and O-300-A, B, C, D
1 1200/12
GO-300-A, C, D, E
1 1500/12
IO-360-A, AB, B, C, D, G, H, J, K
IO-360-CB, DB, GB, HB, JB 1, 2 1500/12 1700/12
IO-360-AF, ES, KB 1, 2 2000/12 2200/12
TSIO-360-A, AB, B, C, D, E, F, H 1
1400/12
1
LTSIO-360-E
1, 2 1400/12 1600/12
TSIO-360-CB, DB, HB, JB
1, 2 1800/12 2000/12
L/TSIO-360-EB, FB, GB, KB, LB, MB, RB, SB
1
E165, E185, E225 Series
1500/12
1
O-470-A, B, E, G, N, P
O-470-J, K, L, M, R, S 1, 2 1500/12 1700/12
O-470-U 1, 2, 3 2000/12 2200/12
IO-470-C, D, E, F, G, H, J, K, L, M, N, P, R, S, U, V, VO 1, 2 1500/12 1700/12
1 1400/12
TSIO-470-B, C, D
1 1700/12
IO-520-B, BA, C, M
1, 2 1700/12 1900/12
IO-520-A, BB, CB, D, E, F, J, K, L, MB
1, 2 2000/12 2200/12
L/IO-520-P

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Engine Inspection and Service
Table 6-1. Engine Time Between Overhaul (TBO)
HOURS/YEARS
ENGINE ENGINE
S/N BEFORE S/N 1006000
ENGINE MODEL SEE NOTE 1006000 AND LATER
1 1200/12
GTSIO-520-F, K
1, 4
GTSIO-520-C, D, H
1600/12
1
GTSIO-520-L, M, N
1 1400/12
TSIO-520-B, D, E, J, K, L, N
TSIO-520-BB, C, DB, EB, G, H, JB, KB, LB, M, P, R, T 1, 2 1400/12 1600/12
TSIO-520-NB 1, 2

TSIO-520-M, P, R 1, 2, 5 1600/12 1800/12

1, 2
TSIO-520-AF, CE, UB, VB, WB
1, 2
L/TSIO-520-AE
2000/12 2200/12
1, 2
TSIO-520-BE
1, 2 1700/12 1900/12
IO-550-A, B, C, D, E, F, L
1, 2
IO-550-G, N, P, R
2000/12 2200/12
1, 2
IOF-550-N
TSIO-550-B, E 1, 2 1600/12 1800/12
TSIO-550-C, G, K, N 1, 2
2000/12 2200/12
1, 2
TSIOF-550-D, J, K, P
1 2000/12
TSIOL-550-A, B, C
1. If an engine consistently accumulates 40 or more hours per month since being placed in service, add 200 hours to recommended TBO.
2. Engines with Serial Number 1006000 or higher include an additional 200 hours to TBO (as noted in Table 6-1, column 3).
3. Applies to: new and rebuilt O-470U Model Specifications 11, 12, 13, 14, 17, 18, and subsequent numbers manufactured, new or rebuilt, or
overhauled (2002 or later).
4. Applies to GTSIO-520-C, D, H engine models listed utilizing cylinder part number 653453, or superseding (cylinder production released
APRIL 1993-verify part number on cylinder flange). Also, all parts must be replaced as directed by the applicable current service bulletins,
illustrated parts catalogs, and overhaul manuals. A log book entry is required.
5. Applies to new and rebuilt TSIO-520-M Spec. 6, 7, and 8; TSIO-520-P Spec. 5 and 6; TSIO-520-R Spec. 7, 9, 10, and 11, or new and rebuilt
TSIO-520-M, P, and R model engines with subsequent specification numbers.

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 Engine Inspection and Service
6-4. Scheduled Inspections
Scheduled inspections are performed at predetermined intervals to verify the system and
subsystem integrity. Scheduled inspections and maintenance are intended to enhance
serviceability by discovering minor discrepancies and correcting them before the
condition degrades. Scheduled inspections are based on calendar days or operating hours
or a combination of both.
NOTE: Inspection intervals listed in Section 6-2 apply to conventional,
spark ignited engines equipped with magnetos. For FADEC equipped
engines, reference the inspection and maintenance instructions in the
primary ICA (reference Section 1-1.1).
Table 6-2. Engine Inspection and Maintenance Schedule
Interval
Cumulative
Operating 
Hours Calendar Task Reference
NOTE: If operating hours and a calendar period are specified, perform the inspection coincident
with the earliest occurrence.

5 --- Drive Belt (optional equipment) Tension Check (One Time) Section 6-4.1
10 --- Hartzell Alternator Initial Inspection (One Time) Section 6-4.1
Initial operation inspection and service after placing a new, rebuilt,
or overhauled engine in service, including cylinder replacement.
25 6 months Section 6-4.2
Repeat this inspection after each 25 hours of operation until oil
consumption stabilizes.
25 4 months Oil Change (with integral oil screen) Section 6-4.8
50 4 months 50-Hour engine inspection and service Section 6-4.3
100 Annual 100-hour engine inspection and service Section 6-4.4
--- Annual Replace FADEC Backup Battery Primary ICA
100 Annual Clean FADEC fuel distribution block1 Primary ICA
100 Annual Clean FADEC fuel filter1 Primary ICA
300 Annual Clean fuel injector nozzles2 Section 6-4.4
500 4 years Magneto inspection2 Section 6-4.4
500 --- 500-hour inspection and service Section 6-4.5

NOTE: At engine TBO (Section 6-3), engine accessories, including the starter, alternator,
magneto, fuel system and turbochargers must be replaced with new assemblies, factory rebuilt
assemblies, or assemblies which have been overhauled according to FAA approved procedures.

1. IOF-240 and IOF-550 only

2. Not applicable to FADEC engines.

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Engine Inspection and Service
6-4.1. One Time Post - Installation Inspections
Check the tension of new drive belts after the first five hours of operation unless a shorter
duration is specified in the primary ICA (Reference Section 1-1.1). Adjust belt tension, as
required, according to the instructions in Section 6-4.10.4, “Belt Tension Check and
Adjustment.”
NOTE: Some 360 Series engines require an initial inspection of a new
alternator or compressor drive belt after twenty minutes of operation.
Refer to the primary ICA to verify inspection belt tension inspection
interval.
1. Perform a visual inspection of the alternator(s) and associated wiring and hardware
after the first ten hours of operation, unless the primary ICA (Ref: Section 1-1.1)
specifies an earlier inspection period.
2. Inspect the bolts and safety wire application.
3. Look for signs of arcing or overheating.
4. Check the cooling duct connections for cleanliness and security.
5. Check terminals and insulators for tightness and condition.
6-4.2. 25-Hour Initial Operation Inspection
Frequency
• Twenty-five (25) hours or six months (whichever occurs first) after:
• Placing a new, rebuilt, or overhauled engine in service
• Replacement of one or more engine cylinder and/or piston rings
• After every 25 hours of engine operation until oil consumption stabilizes
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
Procedure
WARNING
Correct all fuel or oil leaks. Flammable petroleum products
may ignite if exposed to an ignition source.
1. Perform a visual inspection according to instructions in Section 6-4.6; correct any
discrepancies.
NOTE: For FADEC engines, perform an “Engine Operational Check”
according to instructions in the primary ICA rather than a Ground Engine
Run.

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 Engine Inspection and Service
2. Perform a normal “Engine Start” and “Ground Run-up” according to instructions in
the AFM/POH. When the engine reaches normal operating temperatures, check the
following:
a. Idle RPM ..................................................... AFM/POH
b. Idle Mixture Rise ........................................ AFM/POH
c. Acceleration ................................................ Smooth from IDLE to Wide Open
If acceleration is rough or the Idle RPM or Idle Mixture Rise is outside the
parameters specified in Section 6-4.7.1, perform an “Engine Operational Check”
according to Section 6-4.7 and adjust the fuel system accordingly.
3. Determine oil consumption by reviewing engine log book service record. Calculate
the brake specific oil consumption (BSOC) using the formula in the primary ICA
(Ref: Section 1-1.1). If oil consumption exceeds the maximum limit, consumption
is excessive, proceed to step 3a. If consumption is acceptable, proceed to step 4.
a. If oil consumption is excessive, troubleshoot according to the instructions in
Chapter 8, “Troubleshooting.”
b. Perform a “Cylinder Borescope Inspection” according to the instructions in
Section 6-4.11.3.
c. Service the engine with mineral oil conforming to SAE J1966 rather than the
ashless dispersant oil specified in step 4. Repeat this inspection after 25 hours of
operation.
4. Change the oil and filter according to instructions in Section 6-4.8.2, “Oil Change.”
Fill the oil sump to the proper capacity for the engine model (See engine
specification section of Overhaul Manual (Ref: Section 1-1.1)) with fresh, ashless
dispersant aviation engine oil conforming to SAE J1899 (Section 3-1).
5. Remove and inspect the induction air filter. Clean or replace the filter media if
necessary. Verify the induction air filter is installed properly; tighten any loose
fastening hardware. With the induction air filter installed, verify the induction air
filter retainer is properly installed and the attaching hardware is secure in
accordance with the aircraft manufacturer's instructions.
6. Inspect the induction/cylinder drains (if equipped) according to the instructions in
Section 6-4.20.
7. For any other optional engine accessories, refer to the accessory manufacturer’s
maintenance instructions for inspection criteria.

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Engine Inspection and Service
6-4.3. 50-Hour Engine Inspection
Frequency
• 25 hours after the 25-Hour Initial Operation Inspection
• After every 50 hours (or four months) of engine operation
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
Procedure
WARNING
Correct all fuel or oil leaks. Flammable petroleum products
may ignite if exposed to an ignition source.
1. Perform a “Visual Inspection” according to instructions in Section 6-4.6; correct any
discrepancies.
NOTE: For FADEC engines, perform an “Engine Operational Check”
according to instructions in the primary ICA rather than a Ground Engine
Run.
2. Perform a normal “Engine Start” and “Ground Run-up” according to instructions in
the AFM/POH. When the engine reaches normal operating temperatures, check the
following:
a. Idle RPM..................................................... AFM/POH
b. Idle Mixture Rise ........................................ AFM/POH
c. Acceleration ................................................ Smooth from IDLE to Wide Open
If acceleration is rough or the Idle RPM or Idle Mixture Rise are outside the
normal operating parameters specified in the primary ICA (Ref: Section 1-1.1),
perform an “Engine Operational Check” according to the instructions in
Section 6-4.7.
3. Establish an oil analysis profile by collecting an oil sample according to the
instructions in Section 6-4.8.4, “Oil Sample Collection” and Section 6-4.8.5, “Oil
Trend Monitoring and Spectrographic Oil Analysis.”
4. Change the engine oil and filter according to the Section 6-4.8.2, “Oil Change.” Fill
the oil sump to the proper capacity for the engine model (Ref: Section 1-1.1) with
fresh, ashless dispersant aviation engine oil conforming to SAE J1899 (Section 3-1).
5. Perform an “Induction System Inspection” according to Section 6-4.14.
6. For applicable turbocharged engines, lubricate the wastegate butterfly valve and
clean the oil supply check valve according to the instructions in Section 6-4.21 and
Section 6-4.21.1, respectively.
7. Inspect cylinder drains according to the instructions in Section 6-4.20.

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 Engine Inspection and Service
8. Inspect 1/2” cylinder base flange nuts (Part No. 652541) on 470, 520, and 550
engines for a coating of LPS Procyon or LPS 3. If nuts are dry, perform an initial
flange nut inspection according to instructions in Section 6-4.11.1, steps 5 - 9.
9. If a battery serves as the FADEC secondary power source, perform the “FADEC
Backup Battery Inspection” according to instructions in the primary ICA.
10. For any other optional engine accessories, refer to the accessory manufacturer’s
maintenance instructions for inspection criteria.
6-4.4. 100-Hour (Annual) Engine Inspection
Frequency
The 100-Hour Inspection is accomplished under two circumstances:
• After every 100 hours of accumulated engine operation
• Annually, if the engine did not accumulate 100 hours of operation during the calendar
year since the last 100-Hour Engine Inspection.
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
Procedure
WARNING
Correct all fuel or oil leaks. Flammable petroleum products
may ignite if exposed to an ignition source.
NOTE: The fuel injector nozzles must be cleaned after the first 100-Hour
Inspection after installation of a new, rebuilt or overhauled engine.
Thereafter, clean the nozzles every 300 hours or annually.
1. Perform a “Visual Inspection” according to instructions in Section 6-4.6; correct any
discrepancies.
NOTE: For FADEC engines, perform an “Engine Operational Check”
according to instructions in the primary ICA rather than Section 6-4.7.
2. Perform an “Engine Operational Check” according to instructions in Section 6-4.7.
3. Collect an engine oil sample according to the instructions in Section 6-4.8.4, “Oil
Sample Collection” and submit it for analysis according to Section 6-4.8.5, “Oil
Trend Monitoring and Spectrographic Oil Analysis.”
4. Perform the “Cylinder Inspections” according to instructions in Section 6-4.11. The
cylinder inspections consist of multiple inspections and checks including Cylinder
Power Stroke Area, Differential Pressure, Borescope, Baffle, Cowling, and Cylinder
Mounting Deck Inspections.
5. Inspect the 1/2” cylinder base flange nuts (Part No. 652541) on 470, 520, and 550
engines according to instructions in Section 6-4.11.1, steps 5 through 9.
6. Perform a “Crankcase Inspection” according to Section 6-4.12.

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Engine Inspection and Service
7. Perform an “Engine Mount Inspection” according to Section 6-4.13.
8. Perform an “Induction System Inspection” according to Section 6-4.14.
9. Perform an “Ignition System Inspection” according to Section 6-4.15.
10. For the IOF-240-B engine only, perform a “Throttle Position Switch Inspection”
according to instructions in the primary ICA.
11. For FADEC engines only, perform a “Ground Strap Continuity Test” according to
instructions in the primary ICA.
12. For FADEC engines only, perform a “FADEC Backup Battery Inspection”
according to instructions in the primary ICA.
13. Perform an “Engine Gauge Inspection” according to Section 6-4.16.
14. Perform a “Fuel System Inspection” according to Section 6-4.17.
15. Perform an “Engine Control Linkage Inspection” according to Section 6-4.19.
16. Perform an “Induction System Drain Inspection” according to Section 6-4.20.
17. Inspect the Exhaust system according Section 6-4.21.
18. Change the engine oil and filter according to the Section 6-4.8.2, “Oil Change.” Fill
the oil sump to the proper capacity for the engine model (Ref: Section 1-1.1) with
fresh, ashless dispersant aviation engine oil conforming to SAE J1899 (Section 3-1).
19. Inspect installed accessories for mounting security, condition, and proper operation
according to the aircraft maintenance manual or accessory manufacturer’s
instructions. Inspect Hartzell alternator brush holders for soot accumulation. If large
amount of soot is present, inspect brushes (Section 6-4.22) according to the
alternator manufacturer’s ICA.
NOTE: For FADEC engines, perform an “Engine Operational Check”
according to instructions in the primary ICA rather than Section 6-4.7.
20. Perform an “Engine Operational Check” according to instructions in Section 6-4.7.
21. For any other optional engine accessories, refer to the accessory manufacturer’s
maintenance instructions for inspection criteria.

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 Engine Inspection and Service
6-4.5. 500-Hour Engine Inspection
Frequency
After each 500 hours of accumulated engine operation
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
Procedure
1. Complete the “100-Hour (Annual) Engine Inspection” requirements in Section 6-
4.4.
NOTE: The following step does not apply to FADEC engines.
2. Replace non-Continental magnetos with new, rebuilt, or serviceable units. Perform a
500-Hour Magneto Inspection on Continental magnetos according to the
Continental Magneto Service Manual (See Section 1-2.5, “Related Publications.” )
3. Replace paper type induction air filters according to the aircraft manufacturer’s
instructions, regardless of condition.
4. Perform an “Alternator Inspection” according to the instructions in Section 6-4.22.
Inspect and test the alternator for proper operation.
5. For any other optional engine accessories, refer to the accessory manufacturer’s
maintenance instructions for inspection criteria.

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Engine Inspection and Service
6-4.6. Visual Inspection
Frequency
Begin any service interval with a visual inspection
Procedure
1. Verify the engine nacelle is clean and free of fuel leaks, oil leaks, dirt and debris.
2. Inspect all fuel and oil lines for signs of chafing.
3. Inspect the oil cooler and oil filter (or screen) for signs of leaks and physical
discrepancies.
4. Check the following on the engine for cracks, dents, pitting or physical damage:
a. External cylinder barrels
b. Cylinder barrel fins
c. Areas between and adjacent to the cylinder barrel fins.
d. External surfaces of the cylinder head, including areas around
1) Cylinder head fins
2) Top and bottom spark plug bosses
3) Fuel nozzle bosses
4) Crankcase external surfaces
5) Accessories
6) Support structures adjacent to accessories
NOTE: If cylinder discrepancies are discovered during the visual
inspection, perform the “Cylinder Inspections” in Section 6-4.11.
5. Check security of engine and accessory wiring harnesses, including ignition leads.
Check for signs of thermal breakdown, chafing, deterioration or improper routing.
6. Replace broken or damaged cushion clamps and stressed or broken wire ties.
7. Check magnetos for external damage, cracks and mounting security. Ensure the
ignition plate is securely fastened to the magneto and the harness is properly routed.
8. Inspect external drive belts for nicks, cracks and visible wear; replace belts
exhibiting nicks, cracks, or visible wear. Check belt tension and adjust, as required
according to instructions in Section 6-4.10.4.
9. Inspect the exposed area of the crankshaft between the crankshaft nose oil seal and
the propeller flange for evidence of corrosion. If corrosion is detected, use a Scotch-
Brite® pad and a no-corrosive soap solution to remove surface corrosion.
CAUTION: Adequately mask the prop flange bolt holes and the
forward prop contact surface to prevent paint damage to nut/washer
bearing surfaces.
a. If the cleaning process eliminated the corrosion and no evidence of pitting exists,
apply a single coat of high performance rust preventive acrylic enamel (designed
for steel), minimal thickness required for coverage, not on load bearing surfaces

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 Engine Inspection and Service
according to the paint manufacturer’s instructions to the exposed portion of the
crankshaft to prevent further corrosion.
b. If cleaning is unsuccessful (suspected corrosion has advanced to pitting),
disassemble the engine and replace the crankshaft.
10. Check electrical connectors for signs of corrosion or contamination; if external
corrosion or contamination is discovered, disconnect the connectors and inspect the
internal pins for corrosion or contamination.
11. Inspect installed accessories for proper mounting and security. Inspect brush holders
for soot accumulation. If large amount of soot is present, inspect brushes (Section 6-
4.22).
NOTE: For items 12 - 16, inspect for obvious signs of physical damage,
wear or deterioration, loose or missing hardware, leaks or foreign material
that may hinder normal operation. Correct any discrepancies.
12. Inspect the physical security of the fuel system.
13. Inspect the physical integrity of the induction system airbox, ducts, seals and
gaskets.
14. Inspect the physical integrity of the lubrication system.
15. Inspect the physical integrity of the turbocharger and exhaust system.
a. Inspect the stacks, risers, elbows and transitions for burns, cracks or leaks.
b. Inspect turbocharger and exhaust system hardware and joints for stress.
c. Inspect slip joints for leaks, bulges, cracks, deformation, or hot spots.
d. Inspect multi-segment V-band clamp spot welds (or rivets) for cracks or physical
damage.
1) Inspect the corner radii of clamp inner segments for cracks with a flashlight
and inspection mirror.
2) Inspect the V-band clamp outer band for flatness, especially within two
inches of spot-weld tabs that retain the T-bolt fastener variance must be less
than 0.062 in.
e. Inspect the heat exchanger, if installed, seams, joints and transition slip joints for
evidence of leakage or cracks using a mirror or flexible borescope. Replace any
heat exchanger assembly that exhibits cracks or is suspected of leaking.
16. Repair any observable damage or deficiency before the aircraft is returned to
service. Refer to Chapter 10, Non-Overhaul Repair and Replacement Procedures.

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Engine Inspection and Service
6-4.7. Engine Operational Check
WARNING
Flight is prohibited until the engine successfully completes the
operational check and is released for normal operation. If,
during an operational check or engine warm-up, abnormal
operation is observed or leaks occur, do not take-off. Determine
the cause of the problem and take corrective action.
NOTE: The following instructions apply to engines equipped with
Continental continuous flow fuel injection systems only. For engines
equipped with a carburetor (C-75, C-85, C-90, O-200, O-300, O-470
(except GCI model)), a servo controlled fuel injection system (GTSIO-
520-F or K, L/TSIO-360-RB, TSIO-520-WB), FADEC controlled
engines (IOF-240, IOF-550, TSIOF-550), or engines modified by STC,
follow the instructions in the primary ICA to verify the engine meets
operational specifications.
NOTE: For TIARA engines, reference Service Document M75-3 and the
primary ICA (X30144) for fuel system setup instructions.
An engine operational check must be performed after any of the following:
• Engine Installation
• Fuel Injection System parts replacement, maintenance or troubleshooting
• Post-Overhaul
• Return from storage
• After each 100-Hour/Annual
Perform the tasks listed in Table 6-3 on a newly installed, repaired or overhauled engine
before the engine can be released for normal flight. Record engine operational check
results on a copy of the “Engine Operational Checklist”, Table 6-26; substitute forms
created by the organization performing the engine operational check may be used.
Table 6-3. Engine Operation Prerequisites
Sequence Requirement Section Reference
1 Prepare the engine for operation Maintenance Preflight Inspection
2 Check Engine Operation Engine Operational Check
3 Complete the Engine Operational Checklist “Engine Operational Checklist” (Table 6-26)
4 Perform Flight Check “Flight Check” in Section 7-2.41
1. and according to the AFM/POH

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 Engine Inspection and Service
6-4.7.1. Fuel Injection System Specifications
NOTE: Engines may not reach rated full power RPM during ground run-
up due to atmospheric, environmental, or configuration limitations. This
condition is normal, occurring most often when operating naturally
aspirated engines configured with a fixed pitch propeller. A correction
factor must be applied to reduce the fuel pressure to the lower maximum
RPM observed during fuel system adjustments on the ground. See
Section 6-4.7.1.1 for RPM correction factors.
Table 6-4. Fuel System Adjustment Values
Idle and FULL POWER Fuel Pressures and Flows
Manifold
Absolute Metered
Prop. Pressure Unmetered Nozzle Fuel Fuel
Engine1 RPM (MAP) Pump PSI 2
PSI3 (lbs/hr)4 (gal/hr)4
IO-240-A, B 1000 29.5 9.4- 9.8 - - -
Table 6-6 Table 6-6 Table 6-6 Table 6-6 65 - 70 11.0 - 11.9
IO-346-A, B 600 - 7.0 - 7.5 - - -
2700 19.0 - 21.0 12.5 - 14.0 78 - 85 13.3 - 14.5
IO-360-A, AB, C, CB, D5, DB5, G, GB, H, HB 600 - 7.0 - 9.0 -
2800 24.0 - 27.0 15.8 -18.2 100 - 106 17.0 - 18.1
IO-360-AF 600 - 7.0 - 9.0 - -
2800 23.0 - 26.0 14.3 - 16.5 100 - 107 17.0 - 18.1
IO-360-ES 6 600 - 7.0 - 9.0 - -
2800 23.0 - 26.0 14.3 - 16.5 100 - 107 17.0 - 18.1
IO-360-ES (Cirrus - Sea Level) 6, 7 600 - 7.0 - 9.0 - -
2700 21.0 - 24.0 13.8 - 15.5 96 - 102 16.4 - 17.4
IO-360-ES (Cirrus - 1500 ft press. alt.) 6, 7 600 - 7.0 - 9.0 - -
2700 19.0 - 22.0 13.3 - 14.6 94 - 98 16.0 - 16.7
IO-360-J, JB 600 - 7.0 - 9.0 - - -
2600 8 24.0 - 27.0 15.8 -18.2 100 - 106 17.0 - 18.1
IO-360-K, KB 600 - 7.0 - 9.0 - -
2600 21.0 - 24.0 14.3 - 16.3 93.5 - 97.5 15.9 - 16.6
TSIO-360-A, AB 600 - 6.5- 7.5 - - -
2800 32.0 27.2 - 31.2 15.8 - 16.7 119 - 124 20.1 - 21.0
TSIO-360-B, BB 600 - 6.5 - 7.5 - - -
2800 32.0 27.2 - 31.2 15.8 - 16.7 115 - 124 20.1 - 21.0
TSIO-360-C, CB 600 - 6.5 - 7.5 - - -
2800 37.0 34.0 - 37.0 16.7 - 19.3 135 - 145 23.0 - 24.7
TSIO-360-D, DB 600 - 6.5 - 7.5 - - -
2800 36.0 34.0 - 37.0 16.7 - 19.3 135 - 145 23.0 - 24.7
TSIO-360-E, EB, LTSIO-360-E, EB 700 - 6.25 - 6.75 - - -
2575 40.0 43.0 - 46.0 15.8 - 18.3 130 - 140 22.1 - 23.8
TSIO-360-F, FB 700 - 6.25 - 6.75 - - -
2575 41.0 40.0 - 43.0 15.8 - 18.3 130 - 140 22.1 - 23.8
TSIO-360-G, GB 700 - 6.25 - 6.75 - - -
2700 40.0 45.0 - 49.0 16.7 - 19.3 135 - 145 23.0 - 24.7
TSIO-360-H, HB 600 - 6.5 - 7.5 - - -
2800 34.5 29.0 - 33.0 14.9 - 17.3 125 - 135 21.3 - 23.0

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Engine Inspection and Service
Table 6-4. Fuel System Adjustment Values
Idle and FULL POWER Fuel Pressures and Flows
Manifold
Absolute Metered
Prop. Pressure Unmetered Nozzle Fuel Fuel
Engine1 RPM (MAP) Pump PSI2 PSI3 (lbs/hr)4 (gal/hr)4
TSIO-360-JB 600 - 6.5 - 7.5 - - -
2800 37.0 34.5 - 37.5 16.7 - 19.3 134 - 145 22.8 - 24.7
TSIO-360-KB, L/TSIO-360-KB 700 - 6.5 - 7.5 - - -
2800 40.0 36.0 - 39.0 17.7 - 21.2 140 - 155 23.8 - 26.4
TSIO-360-LB 700 - 6.25 - 6.75 - - -
2700 40.0 34.0 - 38.0 14.7 - 16.7 135 - 145 23.0 - 24.7
TSIO-360-MB 700 - 6.25 - 6.75 - - -
2700 36.0 28.0 - 32.0 13.6 - 15.3 125 - 135 21.3 - 23.0
L/TSIO-360-RB 700 - 25 Minimum MFG9 - -
2600 38.0 35.0 - 55.0 - 140 - 150 23.3 - 25.5
TSIO-360-SB 700 - 6.25 - 6.75 - - -
2600 39.0 31 - 36 15.1 - 17.8 131 - 151 22.3 - 25.7
O-470-GCI 600 - 9.0 - 11.0 - - -
2600 23.8 - 25.3 14.7 - 16.9 122 - 129 20.8 - 22.0
IO-470-C, G, P, R 600 - 9.0 - 11.0 - - -
2600 24.7 - 27.7 14.8 - 17.3 123 - 130 21.0 - 22.1
IO-470-D, E, F, H, L, M, N, S, U 600 - 9.0 - 11.0 - - -
2625 25.0 - 28.0 15.0 - 17.5 124 - 131 21.1 - 22.3
IO-470-J, K 600 - 5.5 - 7.0 - - -
2600 24.7 - 27.7 14.8 - 17.3 123 - 130 21.0 - 22.1
IO-470-V 600 - 6.5 - 7.5 - - -
2625 28.3 - 29.8 17.8 - 18.8 123.5 - 131 21.0 - 22.3
IO-470-VO 600 - 6.5 - 7.5 - - -
2625 28.8 - 31.0 17.8 - 18.8 132 - 137.5 22.5 - 23.4
GIO-470-A 450 - 9.0 - 11.0 - - -
2400 26.0 - 28.0 15.5 - 16.5 145 - 155 24.7 - 26.4
TSIO-470-B, C, D 600 - 5.5 - 6.0 - - -
2600 35.0 28.0 - 30.0 15.0 - 17.0 145 - 155 24.7 - 26.4
IO-520-A, J 600 - 9.0 - 11.0 - - -
2700 29.0 - 32.0 15.9 - 18.2 136 - 146 23.2 - 24.9
IO-520-B, BA, BB C, CB 600 - 9.0 - 11.0 - - -
2700 28.0 - 31.0 14.9 - 17.2 136 - 146 23.2 - 24.9
IO-520-D, F, K, L 600 - 9.0 - 11.0 - - -
2850 30.0 - 33.0 17.0 - 19.4 143 - 153 24.4 - 26.1
IO-520-E 600 - 9.0 - 11.0 - - -
2850 29.0 - 32.0 16.1 - 18.3 143 - 153 24.4 - 26.1
IO-520-M, MB 600 - 6.0 - 7.0 - - -
2700 29.0 - 32.0 16.7 - 19.3 136 - 146 23.2 - 24.9
IO-520-P, LIO-520-P 600 - 6.0 - 7.0 - - -
2500 26.2 - 26.9 14.3 - 16.2 130 - 140 22.1 - 23.9
TSIO-520-AE, LTSIO-520-AE 600 - 7.5 - 8.5 - - -
2400 32.5 34.5 - 38.0 15.2 - 16.5 160 - 165 27.3 - 28.1
TSIO-520-AF 600 - 5.5 - 6.5 - - -
2700 35.5 35.0 - 39.0 18.4 - 19.9 180 - 186 30.7 - 31.7
TSIO-520-B, BB 600 - 5.5 - 7.0 - - -
2700 32.0 29.0 - 32.0 16.0 - 17.9 165 - 175 28.1 - 29.8

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 Engine Inspection and Service
Table 6-4. Fuel System Adjustment Values
Idle and FULL POWER Fuel Pressures and Flows
Manifold
Absolute Metered
Prop. Pressure Unmetered Nozzle Fuel Fuel
Engine1 RPM (MAP) Pump PSI2 PSI3 (lbs/hr)4 (gal/hr)4
TSIO-520-BE 600 - 5.5 - 7.0 - - -
2600 38.0 25.0 - 28.0 12.7 - 14.1 214 - 224 36.5 - 38.2
TSIO-520-C, H 600 - 5.5 - 7.0 - - -
2700 32.5 29.0 - 32.0 15.3 - 17.2 160 - 170 27.3 - 29.0
TSIO-520-CE 600 - 5.5 - 6.5 - - -
2700 37.0 33.0 - 36.0 16.2 - 18.0 215 - 225 36.6 - 38.3
TSIO-520-D, DB 600 - 5.5 - 7.0 - - -
2700 32.5 29.0 - 32.0 13.3 - 15.1 160 - 170 27.3 - 29.0
TSIO-520-E, EB 600 - 5.5 - 6.5 - - -
2700 34.5 31.0 - 34.0 15.6 - 17.7 175 - 185 29.8 - 31.5
TSIO-520-G 600 - 5.5 - 6.5 - - -
2700 35.0 31.0 - 34.0 15.8 - 17.6 181 - 191 30.8 - 32.5
TSIO-520-J, JB 600 - 5.5 - 6.5 - - -
2700 36.0 31.0 - 34.0 16.9 - 18.7 170 - 178 29.0 - 30.3
TSIO-520-K, KB 600 - 5.5 - 7.0 - - -
2700 33.0 29.0 - 32.0 15.1 - 17.4 163 - 175 27.8 - 29.8
TSIO-520-L, LB 600 - 25 Minimum MFG10 - -
2700 38.0 45.0 - 55.0 180 - 190 30.7 - 32.4
TSIO-520-M, R 600 - 5.5 - 6.5 - - -
2700 36.5 33.0 - 37.0 16.9 - 19.9 170 - 186 29.0 - 31.7
TSIO-520-N, NB 600 - 5.5 - 6.5 - - -
2700 38.0 32.0 - 35.0 16.9 - 19.9 170 - 186 28.9 - 31.7
TSIO-520-P 600 - 5.5 - 6.5 - - -
2700 36.5 33.0 - 37.0 18.4 - 19.9 180 - 186 30.7 - 31.7
TSIO-520-T 600 - 5.5 - 6.5 - - -
2700 39.5 33.0 - 37.0 16.3 - 18.1 185 - 195 31.5 - 33.2
TSIO-520-UB 600 - 5.5 - 6.5 - - -
2700 36.0 33.0 - 37.0 14.4 - 16.0 195 - 205 33.2 - 34.9
TSIO-520-VB 600 - 5.6 - 6.5 - - -
2700 40.5 36.0 - 39.5 16.9 - 18.7 200 - 210 34.1- 35.8
TSIO-520-WB 600 - 25 Minimum - - -
2700 39.5 45.0 - 55.0 MFG11 190 - 200 32.4 - 34.1
GTSIO-520-C 525 - 4.0 - 7.0 - - -
2400 34.5 30.0 - 33.0 16.5 - 17.5 215 - 225 36.6 - 38.3
GTSIO-520-D, H 467 - 4.0 - 7.0 - - -
2267 39.5 30.5 - 35.0 15.7 - 17.3 250 - 260 42.6 - 44.3
GTSIO-520-F, K11 600 - 6.75 - 7.25 - - -
2267 44.5 38.0 - 41.0 17.4 - 18.8 300 - 310 51.1 - 52.8
GTSIO-520-L, N11 467 39.0 4.0 - 7.0 - - -
GTSIO-520-M 2234 40.0 29.5 - 35.0 16.4 - 17.9 255 - 265 43.4 - 45.1
GIO-550-A 600 - 25 Minimum - - -
2267 45 - 55 MFG11 175 - 185 29.8 - 31.5
IO-550-A 6 600 - 8.0 -10.0 - - -
2700 - 32.0 - 36.0 17.7 -20.0 142 - 150 24.2 - 25.6
IO-550-B 6 600 - 8.0 -10.0 - - -
2700 - 29.2 - 36.2 16.5 - 18.4 146 - 156 24.9 - 26.6

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Engine Inspection and Service
Table 6-4. Fuel System Adjustment Values
Idle and FULL POWER Fuel Pressures and Flows
Manifold
Absolute Metered
Prop. Pressure Unmetered Nozzle Fuel Fuel
Engine1 RPM (MAP) Pump PSI2 PSI3 (lbs/hr)4 (gal/hr)4
IO-550-C 6 600 - 8.0 -10.0 - - -
2700 - 31.6 - 37.8 17.6 - 19.6 152 - 160 25.9 - 27.3
IO-550-D, E, F, L 6 600 - 8.0 - 10.0 - - -
2700 32.0 - 36.0 17.2 - 20.0 143 - 155 24.4 - 26.4
IO-550-G 600 - 8.0 -10.0 - - -
2500 - 22.0 - 26.0 14.7 - 16.0 125 - 130 21.3 - 22.1
IO-550-N, P, R 600 - 8.0 -10.0 - - -
2700 - 28.0 - 30.0 19.0 - 21.3 150 - 160 25.6 - 27.3
TSIO-550-B 600 - 7.0 - 9.0 - - -
2700 38.0 32.0 - 36.0 15.3 - 16.9 241 - 252 41.0 - 42.9
TSIO-550-C 600 - 7.0 - 9.0 - - -
2600 35.5 26.0-29.0 12.7 - 13.9 212 - 224 36.1 - 38.1
TSIO-550- E 600 - 7.0 - 9.0 - - -
2700 38.5 32.0 - 36.0 15.3 - 16.9 244 - 254 41.5 - 43.3
TSIO-550- G 600 - 7.0 - 9.0 - - -
2700 34.0 20.5 - 28.5 12.4 - 13.6 201 - 211 35.2 - 35.9
TSIO-550-G  600 - 7.0-9.0 - - -
MOONEY 12 2500 33.5 20.0-23.0 10.4-11.6 177-180 30.0-30.7
TSIO-550- K, N 600 - 7.0 - 9.0 - - -
2500 37.5 20.5 - 28.5 14.2 - 14.8 210 - 220 35.8 - 37.5
TSIOL-550-A 600 - 5.5 - 6.5 - - -
2600 35.0 32.5 - 35.5 17.0 - 19.0 170 - 180 29.0 - 30.7
TSIOL-550-B 600 - 6.0 - 8.0 - - -
2700 35.0 36.0 - 40.0 20.0 - 22.5 175 - 185 29.8 - 31.5
TSIOL-550-C 600 - 6.0 - 8.0 - - -
2600 39.5 37.0 - 40.0 15.0 – 16.5 204 - 216 34.8 – 36.8

1. The setup procedures contained in this bulletin are only for use on engines that have not been modified from their original configuration as
shipped from the factory by Continental. Engines which have been modified by the installation of aftermarket components such as turbo-
normalizing systems, turbocharging systems, intercoolers, after-coolers, fuel nozzles, etc., whether by STC or field approval, must use the
instructions provided by the STC holder or installer. Continental will not accept responsibility or liability for any modified engine set up
according to the instructions contained in these instructions.
2. FULL POWER unmetered fuel pump pressure limits are provided for reference only. Use metered fuel pressure specifications for adjust-
ments at full power.
3. Use for full power, maximum RPM adjustment only. All other parameters for reference only, Footnote 2 applies.
4. May be determined using a calibrated in-line flow measuring device. Otherwise use metered fuel pressure specifications. Refer to Aircraft
Manufacturer's Maintenance Manual for method of verifying accuracy of fuel flow indicator.
5. IO-360-DB engine model specifications equipped with altitude compensating fuel pumps; Flight Test (Section 7-2.4.2) required after fuel
system adjustment.
6. Engine model equipped with altitude compensating fuel pump; Flight Test (Section 7-2.4.2) required after fuel system adjustment.
7. This engine is installed in Cirrus SR20 aircraft. IO-360-ES engines has been derated by Cirrus from original 210 HP at 2800 RPM to 200 HP
at 2700 RPM. Engine data plate reflects original Continental data of 210 HP at 2800 RPM. Refer to Cirrus SR20 Maintenance Manual and
POH.
8. Engine model certified for five minute rated takeoff power at 2800 RPM. Max. continuous power is 2600 rpm.
9. Refer to the aircraft manufacturer's instructions for adjustment procedures.
10. Refer to the aircraft manufacturer's instructions for adjustment procedures.
11. Refer to the aircraft manufacturer's instructions for adjustment procedures.
12. TSIO-550-G installed in Mooney aircraft has been rated to a power level that is less than the approved Type Certificate Data Sheet. Refer to
the Mooney Aircraft Maintenance Manual for setup instructions.

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 Engine Inspection and Service
6-4.7.1.1. Static RPM Compensation
NOTE: Engine driven fuel pump pressures vary with engine RPM. Rated
FULL POWER RPM may not be achieved during ground run-up. Use the
Fuel Flow Compensation Table to adjust the metered pressures if FULL
POWER RPM cannot be achieved. Fuel Pressure compensation for the
IO-240-A and B engine models is provided in Table 6-6.
Table 6-5. Static Ground Setup Compensation Table
Metered pressure vs. RPM @ 70° F fuel temperature
Corrected Metered Pressure
Static Engine RPM Correction Factor
Minimum Maximum
Rated RPM 1
-20 .991
-40 .982
-60 .973
-80 .964
-100 .955
-120 .946

Procedure
To determine the appropriate correction factor:
1. Subtract the maximum static RPM from the maximum rated RPM.
2. Locate the number closest to the difference between rated RPM and maximum
observed static RPM.
3. The formula is: Metered Fuel Pressure Limits x Correction Factor = Corrected
Metered Pressure Limits @ Static Engine RPM.

Multiply the correction factor adjacent to the maximum static RPM by the rated
metered pressure to determine the corrected metered pressure. If the maximum static
engine RPM = 2640, (-60 RPM); Metered Fuel Pressure Range (in Table 6-4) is 14.9
- 17.2, use the Correction Factor of 0.973
Example: IO-520-BB rated RPM 2700
Maximum static RPM 2640
Difference 60
The corrected minimum metered pressure limit @ 2640 RPM is 14.9 x 0.973 = 14.5
The corrected maximum metered pressure limit @ 2640 RPM is 17.2 x 0.973 = 16.7

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Engine Inspection and Service
Table 6-6. IO-240-A, B With Standard Fuel Pump
Full Throttle Static RPM Metered Fuel Pressure Specifications
Full Throttle Nominal Metered Fuel
Static Engine Pressure
RPM (allowed variation ±0.3)
2400 11.2
2350 10.8
2300 10.5
2250 10.2
2200 9.9
2150 9.6
2100 9.4
2050 9.1
2000 8.8
1950 8.6
1900 8.3
1850 8.1
1800 7.8

6-4.7.2. Maintenance Preflight Inspection

Prior to starting the engine, perform a preflight inspection of the engine, propeller, nacelle,
and aircraft. This inspection must be performed prior to the first flight after engine
installation, inspection, troubleshooting, maintenance, or overhaul work to determine if
the aircraft and engine are in an airworthy condition. Do not release a malfunctioning
engine for flight.
WARNING
Operation of a malfunctioning engine can result in additional
damage to the engine, possible bodily injury or death.
Procedure
1. Turn the Master Power Switch and the Ignition Switch to the OFF position.
2. Remove engine cowling according to the aircraft manufacturer’s instructions.
3. Check the throttle, mixture control, propeller (if equipped), carburetor heat (if
equipped) and alternate air supply controls for freedom of movement and full range
of travel.
WARNING
Ensure the propeller arc is clear of personnel and obstructions
before starting the engine.
4. Drain the aircraft fuel sumps according to the aircraft manufacturer’s instructions.
5. Remove, clean, inspect, and reinstall the aircraft fuel screens according to the
aircraft manufacturer’s instructions.
6. Inspect the aircraft vapor return system (if equipped) for proper operation in
accordance with aircraft manufacturer’s instructions.

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7. Purge the aircraft fuel system.
a. Disconnect the fuel supply hose from the engine driven fuel pump and terminate
the fuel supply hose in a large, clean container suitable for waste fuel.
b. Operate the aircraft fuel boost pump (or gravity drain) to allow a minimum of
one gallon (3.8L) of fuel to flow into the container. Inspect the fuel for
contaminants; locate and correct the source of contaminated fuel, if detected.
c. Reconnect the fuel supply line and torque to Appendix B specifications.
WARNING
Use of inaccurate gauges will result in incorrect fuel system
adjustment, probable accelerated engine wear and possible
engine damage.
8. Verify the fuel system components are properly configured (part numbers conform
to type design and parts are installed properly) according to the engine illustrated
parts catalog.
9. Ensure the fuel manifold valve vent (if equipped) and fuel pump drain lines (if
equipped) are properly installed, open and free of obstructions according to the
installation instructions.
10. Inspect the engine control rod ends for wear, proper installation and security in
accordance with aircraft manufacturer’s instructions.
11. Lubricate engine control rod ends and fuel system moving parts using the approved
lubricants listed in Section 3-1 and the aircraft manufacturer’s instructions.
WARNING
The engine is certified for operation with the aviation fuels
specified on the Type Certificate Data Sheet (TCDS). If the
minimum grade required is not available, use the next higher
grade. Use of lower octane rated fuel or jet fuel will result in
damage to, or destruction of, an engine the first time high
power is applied. If the aircraft is inadvertently serviced with
the wrong grade of fuel, or jet fuel, drain the fuel system
completely and service the fuel tanks in accordance with the
aircraft manufacturer's instructions and perform a
“Contaminated Fuel System Inspection” inspection according
to instructions in Section 6-5.6.
12. Service the aircraft fuel system according to the aircraft manufacturer's instructions.
13. Check the engine oil level. Service the oil sump as required with the oil grade
specified in Section 3-1.
14. Verify the engine crankcase breather is secure with no breather air flow restrictions.
15. If the engine is newly installed or being returned to service after long-term storage,
pre-oil the engine according to the instructions in Section 5-2.9.

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16. Verify the induction air filter is clean and securely in place. Replace the air filter
with a clean one if it is dirty; tighten the filter if it is loose.
17. Visually inspect the engine, propeller hub area, and nacelle for evidence of fuel and
engine oil leaks. Correct any discrepancies.
18. Visually inspect the engine and nacelle for debris, loose, missing or broken lines,
hoses, fittings, clamps and connections. Inspect for restrictions to cooling airflow;
remove any debris.
19. Verify all baffles and baffle seals are installed, correctly positioned, and serviceable.
20. If the engine has been exposed to temperatures below 20ºF (-7 C) for more than 2
hours, preheat the engine according to “Engine Preheating” instructions in
Section 7-4.1.1. If the engine has been exposed to an ambient temperature between
20º to 40ºF (-7º to 4º C), refer to the “Cold Weather Starting Without Preheating”
instructions in Section 7-4.1.1.3.
6-4.7.3. Oil Pump Operational Check
1. Perform a Maintenance Preflight Inspection according to Section 6-4.7.2.
2. Perform a normal “Engine Start” according to instructions in Section 7-3.2 and
“Ground Run-up” according to Section 7-3.3 to allow the engine to warm to normal
operating temperatures.
3. Oil Pressure...................................................... Check
RESULT: Verify oil pressure is between 30 and 60 psi (80 psi for TSIO-360-E, EB,
F, FB, GB, KB, LB, MB, RB & SB) which at cruise power RPM. If necessary, adjust
according to the “Oil Pressure Adjustment” instructions in Section 6-4.10.1. If no oil
pressure is noted, shut down the engine immediately and investigate the cause.
4. If no further checks are required, proceed to “Engine Shutdown” in Section 6-4.7.6.

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6-4.7.4. Fuel System Operational Check
CAUTION: Fuel system operational check instructions in this
section and the adjustments in Section 6-4.10.2 apply only to
Continental continuous flow fuel injection systems. For engines
equipped with carburetors or servo controlled fuel systems, refer to
aircraft and/or equipment manufacturer’s instructions.
A fuel system operational check is required after replacement of fuel injection system
components, such as the fuel pump, fuel manifold valve, or fuel injectors. The fuel system
setup is a critical component of proper engine operation.
Follow the test equipment setup instructions in Section 6-4.7.4.1. When the test equipment
is set up properly, proceed with the “Fuel System Operational Checkout Procedure” in
Section 6-4.7.4.3.
NOTE: Fuel system adjustments are interactive. Once begun, perform the
entire procedure for proper fuel injection system operation.
Required Test Equipment
• Portable Tachometer
• Calibrated pressure gauges (Section 2-1)
OR, if available
• Model 20 ATM-C Porta Test Unit (Section 2-1)
NOTE: Pressure gauges must be accurate within +/- 1%. The calibration
period should not exceed one year.
• A calibrated 0-60 psi gauge, graduated in 1 psi increments, to measure unmetered
pressure.
• On naturally aspirated engines, a calibrated 0-30 psi gauge graduated in 0.2 psi
increments, to measure metered pressure, or
• On turbocharged engines, a calibrated differential pressure gauge, 0-30 psid
maximum, graduated in 0.2 psi increments.
• Two Part No. MS51523-B4 swivel tees, used to insert gauges in line with fuel
lines, for metered and unmetered pressure references.
• Hoses of sufficient length to allow personnel and equipment to perform the test at a
safe distance from the propeller arc and blast area.
• A digital hand-held tachometer, capable of verifying aircraft tachometer accuracy
prior to fuel system adjustment.

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6-4.7.4.1. Fuel System Operational Checkout Setup Instructions
Important Setup Notes
CAUTION: For L/TSIO-360 and TSIO-520 engine models equipped
with a fixed (ground adjustable) exhaust bypass, verify the wastegate
is adjusted according to the aircraft manufacturer's instructions.
Failure to do so can result in an improperly adjusted fuel system and
possible engine damage.
1. Test gauge readings must be taken with the gauges held at the same height above the
ground as the fuel system component being measured.
2. Engine driven fuel pump output pressures vary with engine RPM. During ground
operation, full power RPM may not be obtained. Use the “Static RPM
Compensation” instructions found in Section 6-4.7.1.1 to correct the specified
metered pressures if full power RPM cannot be achieved.
3. On turbocharged engines, ensure manifold pressure is adjusted according to the
aircraft manufacturer’s instructions. Engine driven fuel pumps installed on
turbocharged engines are referenced to turbocharger compressor discharge pressure
(upper deck pressure) to achieve full power fuel pump pressure.
4. Turbocharged engines equipped with fuel pressure regulators must indicate a full
power metered pressure and fuel flow five (5) percent higher than the maximum
specified limit when the regulator is disconnected. This is required to ensure
adequate part-throttle fuel flow.
WARNING
Failure to properly support and stabilize component fittings
can result in fitting and/or component damage and loss of
system pressure.
Procedure
1. Perform a Maintenance Preflight Inspection according to Section 6-4.7.2.
2. Loosen and remove the unmetered fuel supply hose from either the fuel pump outlet
fitting, the fuel control assembly inlet fitting, or the throttle and metering assembly
inlet tee (whichever is most accessible). Some engine models have a fuel pressure
connection fitting in the control assembly inlet screen that may be utilized for
unmetered pressure gauge attachment.
NOTE: Some installations may require multiple fittings to adapt the
metered and unmetered test equipment to the fuel injection system.
Connect the unmetered fuel supply hose to the straight end of the tee
connector.
3. For engine models with throttle and metering assemblies (see Figure 6-38), remove
and set aside the cap fitting (P/N 639494) from the inlet tee. This cap will be
reinstalled after setup is complete.

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4. Connect a tee fitting (P/N MS51523-B4) directly to the fuel connection loosened in
step 2 (see Figure 6-3 through Figure 6-6, as applicable). Torque the tee fitting to the
value specified in Appendix B.

Figure 6-1. Part No. MS51523-B4 Swivel Tee

5. Attach the unmetered fuel supply hose to the straight end of the tee fitting 
(P/N MS51523-B4) and torque to the value specified in Appendix B.
6. GAUGE METHOD: If using the 0 to 60 PSI gauge, connect the gauge to the tee
fitting using a length of hose which will provide proper clearance from the engine
cowling and propeller arc. Torque connections to the value specified in Appendix B.
PORTA-TEST METHOD: Connect the unmetered test hose from the Porta-Test unit
to the tee fitting and torque to the value specified in Appendix B.
7. Loosen and remove the metered fuel supply hose from the fuel manifold valve inlet
fitting.
8. Install and torque the second tee fitting directly to the fuel manifold valve inlet
fitting.
9. Attach the metered fuel supply hose to the straight end of the second tee fitting and
torque to the value specified in Appendix B. On certain models there is an optional
capped fitting on the fuel manifold valve in lieu of second tee fitting.
10. GAUGE METHOD: If using the 0 to 30 PSI gauge, connect to the swivel end of the
tee fitting using a hose long enough to provide proper clearance from the engine
cowling and propeller arc. 
PORTA-TEST METHOD: Connect the metered pressure test hose from the Porta-
Test unit to the second tee fitting and torque to the value specified in Appendix B.
11. Torque all connections to the value specified in Appendix B.
12. On turbocharged engine models: 
GAUGE METHOD: If using the 0 to 30 PSID differential gauge pressure fitting,
connect to the metered pressure tee fitting using a hose of sufficient length to
provide clearance from the aircraft and propeller arc. Connect an equal length of
hose to the “suction” side of the gauge and connect the other end to a location to
reference turbocharger compressor discharge (upper deck) pressure (see Figure 6-5
and Figure 6-6).
PORTA-TEST METHOD: connect the Porta-Test manifold pressure hose and the
upper deck pressure hose to the engine following the instructions provided with the
Porta-Test unit.

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13. Turbocharged engine models (incorporating a fuel pressure regulator) must have the
regulator deactivated during the initial fuel system adjustment. (see Figure 6-45).
a. To deactivate the fuel pressure regulator, loosen and remove the fuel line or hose
from the “center” (outlet) port fitting at the pressure regulator.
b. Install a cap on the “center” (outlet) port fitting.
c. Install a plug in the removed line (or hose).
d. Torque the cap and plug to the values specified in Appendix B.
e. Perform a pressurized leak test on the connections prior to proceeding with fuel
system adjustments.
14. GAUGE METHOD: If using the alternative calibrated test gauges, loosen the test
connections at each gauge to bleed the lines of any air. Hold the gauge at or slightly
above the height of the fuel system component during the bleeding operation.
Operate the boost pump only long enough to allow purging of air from the installed
test equipment. Verify that all fuel lines, hoses and fittings are securely torqued and
that no fuel leaks exist before proceeding. Ensure test hoses have been routed clear
of the exhaust system and are securely supported over their entire length to avoid
inaccurate gauge readings.

PORTA-TEST METHOD: Position the throttle control to the FULL OPEN position
and the mixture control to FULL RICH. Operate the aircraft boost pump in
accordance with the aircraft manufacturer’s instructions. Bleed the air from the test
unit and hoses according to the Porta-Test unit instructions.
WARNING
Drain all fuel from the induction system prior to attempting
engine start. Failure to comply may result in hydraulic lock and
subsequent engine failure.
15. Install the engine cowling or cooling shroud during ground operation.
16. Proceed to Section 6-4.7.4.3.

Figure 6-2. Porta-Test Model 20 ATM-C

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6-4.7.4.2. Test Equipment Connection Schematics

Figure 6-3. Typical Naturally Aspirated Fuel System Schematic

(with Fuel Control Assembly)

Figure 6-4. Typical Naturally Aspirated Fuel System Schematic

(Fuel Pump with Integral Mixture Control)

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Figure 6-5. Typical Turbocharged Fuel System Schematic

(with Fuel Control Assembly and Fuel Pressure Regulator)

Figure 6-6. Typical Turbocharged Fuel System Schematic

(Fuel Pump with Integral Mixture Control)

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6-4.7.4.3. Fuel System Operational Checkout Procedure
Procedure
1. Set the aircraft brakes and block the aircraft main landing gear tires.
2. Verify the accuracy of the tachometer, manifold pressure gauge, and fuel flow
gauges prior to making any adjustments; replace faulty gauges.
3. Locate the IDLE speed stop screw (Figure 6-38 or Figure 6-40) on the throttle
assembly and turn it counter-clockwise two complete turns. During the operational
check, IDLE RPM will be controlled manually using the cockpit throttle control.
WARNING
Ensure the propeller area is clear before starting the engine.
4. Fuel Selector Valve .......................................... ON
5. Mixture Control ............................................... FULL RICH
6. Boost Pump (if equipped) ................................ AFM/POH
7. Perform a normal “Engine Start” according to instructions in Section 7-3.2 and
“Ground Run-up” according to Section 7-3.3 to allow the engine to warm to normal
operating temperatures.
NOTE: A puff of white smoke from a new or rebuilt engine, or an engine
returned from storage is normal. The source of the smoke is the remaining
preservation oil in the burning off in the combustion chamber. The smoke
should dissipate quickly; if smoke persists, shut down the engine and
investigate the cause.
CAUTION: Operating the engine without oil pressure will result in
engine malfunction or failure.
8. Throttle............................................................. 600-1000 RPM (One minute)
RESULT: Operate the engine for one minute, gradually increasing the speed to 1000
RPM in 3 minutes.
9. Oil Temperature ............................................... Check
NOTE: Allow the engine oil to reach normal operating temperature
(100°F (38°C) for turbocharged engines or 75°F (24°C) for naturally
aspirated engines) before proceeding to the next step.
10. Boost Pump ...................................................... OFF
11. Mixture Control ............................................... FULL RICH
12. Throttle............................................................. Set to IDLE RPM (Table 6-4)
13. Unmetered Fuel Pressure Gauge...................... Check
RESULT: Unmetered fuel pressure is within the range specified in Section 6-4.7.1.
Maintain engine speed until CHT is 250°F to 350°F (121°C to 177°C) and engine oil
temperature is 160°-180°F. Record the unmetered fuel pressure, regardless of
setting. If the unmetered fuel pressure is not within the limits specified in Section 6-
4.7.1, adjust the fuel pressure according to the instructions in Section 6-4.10.2.

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WARNING
Do not operate the engine at speeds above 1700 RPM until the
oil temperature reaches minimum takeoff temperature (100°F
(38°C) for turbocharged engines or 75°F (24°C) for naturally
aspirated engines) and oil pressure is within the normal
operating range. Operating at speeds above 1700 RPM before
reaching the minimum oil temperature may result in engine
malfunction or engine failure.
NOTE: To eliminate rough idling after mixture rise check, set engine
RPM to 1500-1800 RPM for 15 seconds before returning to IDLE RPM.
14. Mixture Control ............................................... Retard slowly to IDLE CUT-OFF
RESULT: Monitor engine RPM as mixture is leaned; stop leaning when maximum
RPM is achieved and record engine RPM. IDLE mixture rise should be 25 to 50
RPM (50-75 RPM for IO-240-B only) before beginning to drop toward zero. If
mixture rise is less that 25 RPM (50 for IO-240-B), the mixture is too lean. If the
mixture rise is more that 50 RPM (75 for IO-240-B), the mixture is too rich. Adjust
the idle mixture rise according to instructions in Section 6-4.10.2.
NOTE: The IDLE MIXTURE RISE is the difference (or RISE) between
the IDLE RPM at FULL RICH and the maximum achievable IDLE RPM.
15. Mixture Control ............................................... FULL RICH
16. Propeller Governor .......................................... WIDE OPEN
17. Throttle............................................................. WIDE OPEN
RESULT: Check the engine RPM with a portable tachometer. Record the engine
speed on the checklist. If the engine does not reach the rated, full power RPM,
calculate the corrected metered fuel pressure (Table 6-5 or Table 6-6).
NOTE: If no Manifold Pressure is provided for the engine model in
Table 6-4, skip step 18.
18. Manifold Pressure ............................................ Check
RESULT: Manifold pressure should equal the value specified for the engine model
in Section 6-4.7.1. If manifold pressure is not within the specified limits, adjust the
Wastegate Controller according to instructions in Section 6-4.10.3.
19. Metered Fuel Pressure Gauge ............................. Check
RESULT: The full power, metered fuel pressure should equal the value in Section 6-
4.7.1, with Table 6-5 or Table 6-6 correction factor, if applicable. Record the metered
fuel pressure, regardless of setting. If the full power, metered fuel pressure is not within
the specified limits, adjust the metered fuel pressure according to Section 6-4.10.2.
20. Throttle............................................................. Position to desired IDLE RPM
RESULT: adjust IDLE RPM according to instructions in Section 6-4.10.2.
21. Perform a “Flight Check”, if required, according to the instructions in Section 7-
2.4.2.
22. If no further checks are required, proceed to “Engine Shutdown” instructions in
Section 6-4.7.6.

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6-4.7.5. Magneto RPM Drop Check
WARNING
Absence of RPM drop during magneto check may be an
indication of a faulty ignition circuit (Hot Magneto). Should the
propeller be turned by hand (as in during preflight), the engine
could inadvertently start and cause personal injury or death.
Flight is prohibited until the condition is corrected.
CAUTION: When operating on single ignition, some RPM drop and
slight engine roughness as each magneto is switched off should be
noted. Excessive (greater than 150 RPM) RPM drop may indicate a
faulty magneto or fouled spark plugs.
NOTE: If the engine runs roughly after single magneto operation,
increase engine speed to 2200 RPM in the BOTH position and lean the
mixture control until the RPM peaks for ten seconds before returning to
the full rich position to clear the spark plugs and smooth operation before
returning to single magneto operation.
Procedure
1. Start the engine according to the “Engine Start” instructions in Section 7-3.2.
RESULT: No defects noted. Allow the engine oil to warm to normal (100°F (38°C)
for turbocharged engines or 75°F (24°C) operating temperature.
CAUTION: Avoid prolonged single magneto operation to preclude
spark plug fouling.
NOTE: In the instructions below, the term “Magneto Switch” applies to
the method the aircraft manufacturer uses to control the magnetos. Some
manufacturers use a wafer switch to control the starter with four
additional positions for magneto control, labeled OFF, L, R and BOTH.
Toggle switches may be used to accomplish the same action. Adjust
instructions according to the available aircraft controls.
2. Throttle............................................................. 1700 RPM
3. Magneto Switch ............................................... R
RESULT: RPM drop does not exceed 150 RPM; record Left Magneto channel drop
result. Maximum allowable RPM drop spread between magneto channels is 50
RPM.
4. Magneto Switch ............................................... BOTH
5. Magneto Switch ............................................... L
RESULT: RPM drop does not exceed 150 RPM; record Right Magneto channel drop
result. Maximum allowable RPM spread between magneto channels is 50 RPM.
6. Magneto Switch ............................................... BOTH
7. Throttle............................................................. Reduce to IDLE
8. If no further checks are required, proceed to “Engine Shutdown” on page 32.

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6-4.7.6. Engine Shutdown
Procedure
1. Perform a normal engine shutdown according to the “Engine Shutdown”
instructions in Section 7-3.4.
2. Remove installed test equipment.
a. Disconnect the metered fuel pressure test hose from the aircraft fittings.
b. Disconnect the unmetered fuel pressure test hose from between the fuel pump
and the fuel control assembly.
c. Remove any fittings added to adapt the plumbing to the test equipment.
3. Reconnect and torque the fuel system hoses to Appendix B specifications.
a. Connect the unmetered pressure hose between the fuel pump and the fuel control
assembly.
WARNING
Failure to connect and torque fuel system fittings to the proper
specification will result in a fuel leak and potential fire hazard.
CAUTION: Upon completion of fuel system testing or adjustment,
install and torque P/N 639494 cap, if equipped, at the metered
pressure test connection. Use only P/N 639494 cap on the metered
pressure fitting; installation of a pipe thread cap on the flared fitting
may damage the fitting.
b. Install the protective cap (P/N 639494) (or airframe-installed fitting to cockpit
metered pressure gauge) on the fuel manifold valve (metered pressure) or throttle
and metering assembly (metered pressure) fitting, if equipped, and torque the cap
to standard torque for a #4 steel fitting in Table B-8.
4. Leak Check
a. Master Power Switch .................................. ON
b. Mixture........................................................ FULL RICH
c. Boost Pump Switch (if equipped) ............... ON
d. Throttle........................................................ WIDE OPEN
e. Check for leaks in the following areas and correct any discrepancies before
releasing the engine for flight:
1) Induction System
2) Exhaust System
3) Fuel System
4) Lubrication System
f. Boost Pump................................................. OFF
g. Throttle........................................................ IDLE
h. Mixture........................................................ IDLE CUT-OFF
i. Master Power Switch .................................. OFF

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6-4.8. Engine Oil Servicing
The engine lubrication system provides either pressure or splash oil to areas of the engine
subject to frictional loading. A certain amount of oil consumption is normal if the plane is
flown on a regular basis. However, if oil consumption exceeds the “Brake Specific Oil
Consumption” rate in the primary ICA (reference Section 1-1.1) or there is an abrupt change
in the rate of oil consumption, determine the cause and correct it before further flight.
WARNING
Do not fly the aircraft if oil consumption is abnormal or is
suspect; investigate for oil leakage. If no oil leakage is noted,
perform the “Cylinder Inspections” in Section 6-4.11.
6-4.8.1. Check and Replenish Engine Oil Level
Maintain the oil sump capacity at the specified level. To check the oil level or add oil,
perform the following procedure:
WARNING
Check the oil level before each flight and maintain the engine
oil at the specified level. Engine operation with less than the
specified capacity will cause engine malfunction or failure.
Petroleum based aviation engine oil is flammable. Follow fire
hazard precautions. Store oil in a well-ventilated area away
from heat or ignition sources.
NOTE: Ensure the aircraft is on level grade and the engine has been shut
down for at least five minutes for accurate reading on oil gauge rod.
Procedure
1. Withdraw the oil gauge rod (dipstick) (see Figure 6-7 through Figure 6-22 for
engine oil servicing points).
2. Wipe the oil from the oil gauge rod with a clean, lint-free cloth. Avoid getting any
lint or debris in the oil sump.
3. Insert the cleaned oil gauge rod back into the oil sump and withdraw the rod again.
4. Verify the oil on the rod touches, but does not pass the oil fill line on the rod.
NOTE: Oil sump capacities differ by engine models. Refer to the “Engine
Specifications” in the primary ICA (reference Section 1-1.1).
CAUTION: When adding oil, completely remove the protective seal
from the oil container to prevent the seal from falling into the oil fill
port. Prevent any debris from falling into the oil fill port.
5. If more oil is required, add a sufficient quantity of oil meeting the specifications in
Section 3-1 to reach the fill line on the oil gauge rod.
NOTE: If oil is spilled on the engine or nacelle during servicing, clean the
spilled oil immediately and dispose of oily rags and absorbent materials
according to local environmental regulations.
6. Install and lock the oil gauge rod in the fill tube after servicing the engine oil.

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Oil Gauge Rod

and Fill Cap

Oil Pressure
Relief Valve
Oil Temp. Connection
Oil Screen
Oil Drain Plug Oil Sump
0.88” Hex
Figure 6-7. C-75, C-85, C-90 & O-200-A Oil Servicing Points, typical

Figure 6-8. O-200-D & X Oil Servicing Points, typical

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Figure 6-9. IO-240-B Oil Servicing Points, typical

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Figure 6-10. IO-360 Oil Servicing Points, typical

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Figure 6-11. IO-360-AF/ES Oil Servicing Points, typical

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Figure 6-12. TSIO-360 Oil Servicing Points, typical

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Figure 6-13. O-470 Oil Servicing Points, typical

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Figure 6-14. IO-470/TSIO-470 Oil Servicing Points, typical

(also IO-520/TSIO-520 engine models with Sandcast Crankcase)

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Figure 6-15. GTSIO-520 Oil Servicing Points, typical

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Figure 6-16. IO-550-A, B & C Oil Servicing Points, typical

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Figure 6-17. IO-550-D, E & F Oil Servicing Points, typical

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Figure 6-18. IO-550-G & N Oil Servicing Points, typical

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Figure 6-19. IO-550-L Oil Servicing Points, typical

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Oil Fill & Gauge Rod

Oil Cooler

Oil Temperature
Connection

Oil Sump
Drain
Oil Filter
Oil Cooler

Oil Pressure
Connection

Oil Sump
Drain

Figure 6-20. IO-550-P Oil Servicing Points, typical

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Oil Fill & Gauge Rod

Oil Cooler

Oil Temperature
Connection

Oil Sump
Drain

Oil Filter

Oil Cooler

Oil Pressure
Connection

Oil Sump Drain

Figure 6-21. IO-550-R Oil Servicing Points, typical

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OIL FILL/GAUGE ROD

OIL PRESSURE
PROPELLER GOVERNOR PAD 0.5625-18 UNF-2A
MODIFIED AND 20010

OIL TEMPERATURE
0.625-18 UNF-3B

OIL FILTER

OIL DRAIN PLUG

0.88 Hex
.625-18 UNF-3A

Figure 6-22. TSIO-550 Oil Servicing Points, typical

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6-4.8.2. Oil Change
Perform an oil change within 30 minutes of engine shutdown (to obtain a useful oil
sample) according to the oil changes intervals specified in Section 3-2.
NOTE: More frequent oil changes are recommended under extreme usage
(flight training, shuttle service, or crop dusting) or adverse weather conditions
(desert or arctic climates).
Procedure
1. Place a catch basin (approved for collecting oil) beneath the oil sump drain plug.
Remove the oil sump drain plug (Figure 6-7 through Figure 6-22), or quick drain
fitting, and drain the engine oil into the catch basin. Discard the crush washer
(gasket).
2. Collect an oil sample according to the “Oil Sample Collection” instructions in
Section 6-4.8.4. Inspect the oil sump drain plug for evidence of wear material. Metal
fragments on the drain plug may indicate excessive wear or part disintegration.
Evidence of bronze in the oil sump suggests piston pin bushing loss.
CAUTION: Dispose of used engine oil in accordance with local
environmental standards.
NOTE: Continental recommends customers submit a sample of the oil
drained during each oil change, or if engine trouble is suspected, for
spectrographic oil analysis. The first three samples establish the oil analysis
trend baseline. 

The amount of wear material present in new, rebuilt, or overhauled engines is
typically greater during the engine break-in period, tapering off during
subsequent oil changes. If the amount of wear material does not decrease
during subsequent oil changes, note the wear material characteristics (refer to
Section 6-4.8.5, “Oil Trend Monitoring and Spectrographic Oil Analysis”)
and troubleshoot the engine according to instructions in Chapter 8.

Figure 6-23. Disposable Oil Filter and Integral Screen

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3. This step describes how to change the disposable oil filter or integral oil screen (see
Figure 6-23). To change disposable oil filters, follow the instructions in step a. To
change the integral oil screen, follow the instructions in step b.
NOTE: Engines covered in this manual are equipped with either a spin-
on, disposable oil filter or an integral oil screen (Figure 6-23).
Maintenance pertaining to the filter media is listed in the “Engine
Inspection and Maintenance Schedule” in Section 6-2.
a. Disposable Oil Filters:
1) Remove the oil filter (Figure 6-8 through Figure 6-22). Cut the oil filter in
two parts using an Oil Filter Can Cutter (P/N CT-923 (Table 2-1, “Special
Tools List”)).
2) Inspect the oil filter element for metal debris trapped within the filter to
assess the engine condition. If debris is found, wash the filter media in a clean
glass container to determine content. Use a magnet to differentiate the ferrous
materials from non-ferrous particulate. New, rebuilt, or overhauled engines
exhibit more wear material during the break-in period; material found in the
filter media will diminish over time. If wear material in the oil filter does not
diminish, or increases, note the characteristics of the wear material (reference
Section 6-4.8.5, “Oil Trend Monitoring and Spectrographic Oil Analysis”)
and troubleshoot the engine according to instructions in Chapter 8.
CAUTION: Spin-on oil filters are available with an anti-stick coating on
the gasket. Part numbers 658753, 658754, and 658755 oil filters feature
a dry graphite coating and are designed to be installed dry. Before
applying any lubricant to the oil filter gasket, read the manufacturer’s
instructions (Figure 6-24) on the oil filter. Application of any form of
lubricant to the gasket of the anti-stick spin-on oil filter will defeat the
anti-stick properties.
3) To install a new disposable oil filter, read the label to determine the gasket type
and proceed with installation according to the filter manufacturer’s instructions.
Install the new oil filter; torque the filter to Appendix B specifications and
safety wire the filter according to instructions in Appendix C-3.
b. Integral Oil Screens:
1) The integral oil screen is not a disposable maintenance item. If the engine is
equipped with an integral oil screen (Figure 6-23), cut the safety wire from
the oil screen and remove the fastening hardware. Remove the integral oil
screen from the oil pump, or oil screen adapter.
2) Rinse the integral oil screen with mineral spirits over filter paper to clean the
media. Use a magnet to differentiate the ferrous materials from non-ferrous
particulate.
3) After thorough cleaning, install a new copper gasket on the oil screen flange
and install the integral oil screen in the oil pump, or oil screen adapter. Place
a new copper gasket on the plug (or oil temperature sensor provided by
aircraft manufacturer) and thread the screen (or plug) into the housing.

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4) Torque to Appendix B specifications and safety wire according to
instructions in Appendix C-3.

Figure 6-24. Oil Filter with Anti-Stick Gasket Label, typical

4. Install the oil drain plug with a new crush washer (gasket) in the oil sump according
to instructions in Appendix C-10.1
a. Torque the drain plug to Appendix B specifications.
b. Safety wire the drain plug according to instructions in Appendix C-3 to complete
the drain plug installation.
5. Add fresh oil and check the oil level according to instructions in Section 6-4.8.1.
6. Check for oil leaks according to instructions in Section 6-4.8.3.

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6-4.8.3. Check for Oil Leaks
WARNING
Keep the engine compartment, nacelle, and fuselage adjacent to
the nacelle clean to enable detection of oil leaks.
Procedure
1. Perform a normal “Engine Start” according to instructions in Section 7-3.2 and
“Ground Run-up” according to Section 7-3.3 to allow the engine to warm to normal
operating temperatures. Document engine oil pressure and temperature.
2. Shut down the engine according to the “Engine Shutdown” instructions in
Section 7-3.4.
3. Check the engine nacelle, engine compartment, and adjacent area for oil leaks. If
leaks are found, determine the source and correct the cause of the leak(s).
4. Check the oil level in the sump according to Section 6-4.8.1, “Check and Replenish
Engine Oil Level.”
6-4.8.4. Oil Sample Collection
Oil samples may be collected during the oil change procedure, before new oil is added or
between oil changes. The oil sample must be taken after the engine has been operated
within normal operating limits (See Engine Specifications and Operating Limits in
primary ICA (Ref: Section 1-1.1)), including normal cruise and maximum power settings
for at least 30 minutes.
NOTE: Collect oil samples within 30 minutes of engine shutdown.
Procedure
1. Clean any dirt or debris from around the oil sump drain plug.
2. Use the following sample collection devices:
a. Sampling tube and/or funnel
b. Sample vial
NOTE: Oil sampling equipment must be clean and free of debris, foreign
material, or residue to ensure sample integrity and accurate analysis.
3. Collect oil from one of the following sample collection locations consistently
according to the Oil Analysis Laboratory’s oil sampling kit instructions:
a. Midstream of the oil drain flow after 1/3 of the oil has drained from the oil sump.
b. From the oil fill port, at least 2 to 3 inches above the bottom of the oil sump.
NOTE: Never take an oil sample from the bottom of the oil sump or the
oil filter canister.
4. Fill the oil sample tube or vial 3/4 full and tighten the cap.
5. Label the oil sample vial with the date the sample was taken, the serial number of
engine it was taken from, and the submitter’s name and company.

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NOTE: Duplicate oil samples, submitted to different oil analysis
laboratories will render an equal number of different reports. Establish a
rapport with one laboratory and use it consistently for meaningful trend
analysis.
6. Submit the oil sample for analysis. The following laboratories provide thorough,
detailed oil analysis and reporting:
Aviation Oil Analysis Aviation Laboratories
3319 W. Earll Drive 910 Maria Street
Phoenix, AZ 85017 Kenner, LA 70062
6-4.8.5. Oil Trend Monitoring and Spectrographic Oil Analysis
Spectrographic oil analysis identifies concentration, in parts per million (PPM), of wear
material in an oil sample (see Section 6-4.8.4) collected during an oil change. Analysis
begins with the first oil change sample, and continues with successive oil changes. The
first samples establish a baseline. Subsequent samples, taken over time, establish trends.
These trends help determine if wear material is deviating from the baseline.
(Establishment of the baseline and ensuing wear trends assume analysis is done by the
same laboratory using the same method of analysis.)
Spectrographic oil analysis results will vary for reasons exclusive of engine condition.
Chemical composition of engine oils vary by manufacturer. For consistent, meaningful
analysis, service the engine with the appropriate grade of aviation engine oil from the
same manufacturer, collect engine oil samples at regular intervals and submit the samples
to the same laboratory for analysis.

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6-4.9. Ignition System Maintenance
6-4.9.1. Ignition Timing
Reference (latest revision): MSB94-8
Ignition timing instructions apply only to engine models with magneto ignition. For all
FADEC engines, consult the primary ICA.
Equipment Required
• Eastern Technology Corporation Model E25 Timing Indicator (or equivalent)
• Top Dead Center Locator
• Eastern Technology Corporation Model E50 timing light (or equivalent)
CAUTION: Ignition timing drift greater than 4 degrees between
inspections may be an indication of magneto cam wear or breaker
point erosion. Investigate any timing drift greater than 4 degrees.
NOTE: Instructions provided utilize the Eastern Technology Model E25
timing indicator and E50 timing light. If using alternate timing tools,
reference the manufacturer’s instructions.
NOTE: Instructions to turn the crankshaft clockwise or counterclockwise
in Section 6-4.9.1.1 and Section 6-4.9.1.2 reference the pilot’s
perspective, viewed from behind the propeller. Standing in front of the
engine, all directions are opposite of the printed text.
Table 6-7. Magneto Timing Specifications - Geared Engines
Engine Model Crankshaft Angle Propeller Shaft Ratio Propeller Shaft Angle
GO-300 28° BTC 0.75 21° BTC
GIO-470 24° BTC 0.75 18° BTC
GTSIO-520-C 22° BTC 0.75 16.5° BTC
GTSIO-520-D, F, H, K 20° BTC 0.667 13.3° BTC
GTSIO-520-L, M, N 24° BTC 0.667 16° BTC
TIARA 6-285 and 6-320 30° BTC 0.500 15° BTC

Table 6-8. Magneto Timing Specifications - Direct Drive Engines

Engine Model Right Magneto1 Left Magneto1 Notes

A65 30° BTC 30° BTC

A75, A80 29° BTC 32° BTC

C75, C85 28° BTC 30° BTC

C90 26° BTC 28° BTC

O-200-A, B, C 24° BTC 24° BTC 2

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Table 6-8. Magneto Timing Specifications - Direct Drive Engines

Engine Model Right Magneto1 Left Magneto1 Notes

O-200-D 24° BTC 24° BTC

IO-240-A 22° BTC 22° BTC

IO-240-B 26° BTC 26° BTC

C-125 28° BTC 30° BTC

C-145, O-300 26° BTC 28° BTC

E-165, E-185, E-225 26° BTC 26° BTC

O-470-A, E 26° BTC 26° BTC

O-470-B, G, M, P & U 24° BTC 24° BTC

O-470-J 20° BTC 20° BTC

O-470-K, L, R & S 22° BTC 22° BTC

IO-346 24° BTC 24° BTC

IO-360-A, B, C, D, G, H, J & K 20° BTC 20° BTC 3

IO-360-AF & ES 24° BTC 24° BTC

IO-470-C, G, R & P 26° BTC 26° BTC

IO-470-D, E, F, H, L, M, N, S, U, V & VO 20° BTC 20° BTC

IO-470-J, & K 22° BTC 22° BTC

IO-520-A, B, BA, BB, C, CB, D, E, F, L, M, MB, N,

22° BTC 22° BTC
NB

IO-550-A, B, C, D, E, F, G, L, N, P & R 22° BTC 22° BTC

LTSIO-360-E, EB, KB 20° BTC 20° BTC

LTSIO-360-RB 22° BTC 22° BTC

TSIO-470 22° BTC 22° BTC

LTSIO-520-AE 20° BTC 20° BTC

TSIO-360-A, AB, B, C, CB, D, DB, E, EB, F, FB, G,

20° BTC 20° BTC
GB, H, HB, J, JB, K, KB, LB, MB & SB

TSIO-360-RB 22° BTC 22° BTC

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Table 6-8. Magneto Timing Specifications - Direct Drive Engines

Engine Model Right Magneto1 Left Magneto1 Notes

TSIO-520-B, C, D, E, H, J, K, L, N, VB, WB, AE &

20° BTC 20° BTC 3
CE

TSI0520-M, P, R, T, UB & AF 22° BTC 22° BTC 3, 4

TSIO-520-BE 24° BTC 24° BTC

TSIO-550-A, B, C, E, G, K & N 24° BTC 24° BTC

TSIOL-550-A & C 20° BTC 20° BTC

TSIOL-550-B 24° BTC 24° BTC

1. Allowable tolerance is plus or minus one degree unless otherwise noted.

2. O-200-A and –B model engines that have a complete set (4 each) of Continental Part No. 641917 or subsequent (higher) part number
cylinders installed are eligible to have the timing advanced to 28 degrees BTC. This may include a combination of 641917, 649543,
653246, 654377, 653816, 655483, 657454, 657455 and subsequent (higher) part number cylinders. Part No. 641917 was first produced in
1977. The cylinder part number is stamped on the barrel flange. The absence of a cylinder part number may indicate cylinders
manufactured prior to Part No. 641917. Visual acceptance can be determined by the exampled listed in Figure 6-25 and Figure 6-26. For
those engine that have the applicable cylinders and timing advanced, restamp the engine data plate to indicate magneto timing of 28
degrees BTC and make a log book entry noting the change and the part number of the qualifying cylinders installed. Subsequent
installation of cylinders must be of the part numbers listed above to retain the advanced 28 degree BTC timing. Only cylinders
manufactured by Continental qualify for the advanced timing under this manual.
3. Timing specification for “B” Models (i.e. IO-360-DB, I0-520-BB, TSI0-520-EB, etc.) is the same as standard models.
4. Magneto setting tolerance of TSIO-520-P to be plus zero (0) or minus one (1) degree.

Figure 6-25. O-200 28° BTC Timing Figure 6-26. O-200 24° BTC Timing

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6-4.9.1.1. Crankshaft Top Dead Center Alignment
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
CAUTION: Incorrect timing, in addition to a rough running engine,
can lead to detonation, pre-ignition, possible internal engine
damage, or engine failure.

Gravity affects the timing indicator pendulum position. Prior to
checking or adjusting engine timing, level the aircraft (fore to aft) to
avoid friction on the pendulum.
NOTE: Some starters restrict reverse engine rotation. If the engine does
not freely turn in the opposite direction of normal rotation, temporarily
remove the starter to complete magneto to engine timing.
1. Place the fuel selector valve in the OFF position.
2. Turn the ignition switch to the OFF position. Disconnect the aircraft battery
according to the aircraft manufacturer’s instructions.
3. Remove top spark plugs from each cylinder. Find the No. 1 cylinder compression
stroke by placing a finger over the spark plug hole and rotating the crankshaft. When
the cylinder is on the compression stroke, the valves will be closed and pressure will
build as the piston moves to the top of the cylinder. Pressure buildup in the cylinder
can be felt at your fingertip.
4. Install the Top Dead Center (TDC) locator (Figure 6-27) in the No. 1 cylinder spark
plug hole.

Figure 6-27. Timing Disk and TDC Locator Installed

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NOTE: Ensure the timing disk is securely fastened to the propeller to
prevent movement during engine timing.
5. Securely install the timing disk indicator on the crankshaft flange, propeller spinner
or propeller hub using the supplied elastic bands.
6. Turn propeller slowly in the direction of normal rotation until the piston lightly
touches the top dead center locator.
7. Rotate the timing disc until the TDC mark aligns with the weighted pendulum
pointer.
8. Slowly rotate the crankshaft in the opposite direction of normal rotation until the
piston again lightly touches the top dead center locator (Figure 6-28).
NOTE: DIAL INDICATOR POSITIONS SHOWN ARE EXAMPLES
ONLY. POSITIONS ON THE PROTRACTOR/TIMING INDICATOR
TOP DEAD CENTER DISC WILL DIFFER FROM ENGINE TO ENGINE.
LOCATOR INSTALLED

EXAMPLE 85° POSITION

80 90
# 1 CYLINDER

PISTON LIGHTLY
OPPOSITE OF NORMAL
TOUCHING
DIRECTION OF ROTATION
NOTE: THE PROTRACTOR/TIMING INDICATOR SHOWN IS USED WITH THE PROPELLER AND SPINNER INSTALLED.

Figure 6-28. No. 1 Cylinder Positioned at Top of Intake Stroke

NOTE: DIAL INDICATOR POSITIONS SHOWN ARE EXAMPLES

TOP DEAD CENTER ONLY. POSITIONS ON THE PROTRACTOR/TIMING INDICATOR
LOCATOR INSTALLED DISC WILL DIFFER FROM ENGINE TO ENGINE.

EXAMPLE 42.5° POSITION

30 40 50
# 1 CYLINDER

PISTON LIGHTLY
NORMAL DIRECTION OF
TOUCHING
ROTATION
NOTE: THE PROTRACTOR/TIMING INDICATOR SHOWN IS USED WITH THE PROPELLER AND SPINNER INSTALLED.

Figure 6-29. Crankshaft Positioned at TDC

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9. Determine the difference between Top Dead Center (TDC) and the current pointer
indication (Figure 6-28) and divide by two; turn the timing disk to align the pointer
with the resulting number (Figure 6-29), without turning the timing indicator base.
10. Remove the TDC locator from the No.1 cylinder (Figure 6-30).
11. Rotate the crankshaft in the direction of normal rotation on the compression stroke
until the pointer aligns with the 0° mark. On magnetos equipped with impulse
couplings, continue turning the crankshaft in the direction of normal rotation until
each impulse coupling trips. Couplings may trip a few degrees on either side of
TDC. If one or both couplings trip after TDC, rotate the crankshaft opposite of the
direction of normal rotation a few degrees before TDC, then back in the direction of
normal rotation toward TDC. Impulse couplings should not be armed at this point.
12. For direct drive engines, the crankshaft is now positioned at TDC of the No. 1 cylinder
compression stroke, proceed to step 14. For gear driven engines proceed to step 13.

Figure 6-30. Cylinder No. 1 Top of Compression Stroke

13. To determine TDC for geared engines, see the calculations below for the applicable
engine model and rotate the propeller shaft accordingly.
a. For GO-300, GIO-470 and GTSIO-520-C engine models, add 135 degrees to the
value in step 12.
b. For GTSIO-520-D, F, H, K, L, M & N engine models, add 120 degrees to the
value in step 12.
c. For TIARA engine models, add 90 degrees to the value in step 12.
EXAMPLE: For a geared engine with a 0.75 propeller to crankshaft RPM ratio and timing
specification of 24° BTC, the propeller shaft would be 0.75 X 24 degrees or 18° BTC. If
the propeller shaft to crankshaft ratio is 0.667, the propeller shaft timing would be 0.667 X
24 degrees, or 16° BTC.

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14. Turn the crankshaft in the opposite direction of normal rotation past the engine
timing specification to remove gear backlash. Turn the crankshaft in the direction of
normal rotation until the pointer aligns with the engine crankshaft timing (Direct
Drive Table 6-8) or propeller shaft timing angle (Gear Drive step 13 and Table 6-8)
on the timing disk. The engine is now prepared for magneto removal, installation or
magneto to engine timing.

Figure 6-31. No. 1 Cylinder Full Advance Firing Position

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6-4.9.1.2. Magneto to Engine Timing
WARNING
Failure to properly maintain the magneto, harness and/or
spark plugs will lead to internal engine damage and failure.
CAUTION: Timing Indicator Plate, part number 628760 was
discontinued in 1984 due to timing errors attributed to improper use.
Use of timing indicator, part number 628760 is prohibited.
Procedure
1. Complete Section 6-4.9.1.1, “Crankshaft Top Dead Center Alignment.”
NOTE: Be familiar with the test equipment function prior to use. Some
timing lights indicate proper ignition timing by illuminating a lamp; other
models illuminate a lamp until the magneto cam lobe opens the circuit
and turns the lamp off while other timing indicators use an audible signal
to indicate timing status.
2. Disconnect the P-leads from the magnetos. Connect a timing light right lead to the
right magneto switch or P-lead terminal and the left lead to the left switch or P-lead
terminal. Connect the timing light ground lead to a suitable ground on the engine
such as an unpainted bolt or stud.
NOTE: Engines equipped with impulse coupling magnetos must be
turned in the direction of normal rotation past the impulse coupling trip
point prior to centering the pointer at engine timing mark.
3. With the crankshaft in the correct timing position, turn the crankshaft opposite the
direction of normal rotation a few degrees before the engine timing setting in
Table 6-7 to clear valve backlash. Turn the crankshaft in the direction of normal
rotation toward the point of ignition and observe the timing light as the needle
approaches the engine timing setting. As the pointer aligns with the correct ignition
timing, the timing light should indicate proper timing. Lightly tap the end of the
pointer with a finger to verify the pointer position.
4. If the timing light fails to illuminate, loosen the nuts securing the magneto to the
mounting flange and rotate the magneto to the left or right in the mount until the
lamp illuminates. If magneto timing adjustment is not possible, remove the suspect
magneto and repair according to the magneto manufacturer's service instructions.
CAUTION: Do not exceed the specified magneto to flange torque.
Excessive torque will crack the magneto mounting flange.
5. Torque the magneto fasteners to Appendix B specifications.
6. Remove the protractor and timing disk from the propeller flange, spinner or
propeller hub. Reconnect the switch or P-lead wires to the magnetos.
7. Inspect and install spark plugs according to Section 6-4.9.2.
8. Inspect and install the ignition harness according to Section 6-4.9.3.
9. Connect the aircraft battery according to the aircraft manufacturer’s instructions.

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6-4.9.2. Spark Plug Maintenance
Procedure
1. Remove the ignition harness leads from all spark plugs.
2. Remove the top and bottom spark plug from each cylinder. Mark each plug’s
installed location during removal.
NOTE: Many spark plug manufacturer’s offer erosion (go/no-go) gauges
to determine spark plug serviceability. If the spark plug meets the “go”
criteria, it may remain in use, if no performance issues are noted.
3. Inspect plug condition using Figure 6-32 as a guide to spark plug serviceability.
Discard spark plugs that fail to meet the “normal electrode condition” characteristics
depicted in Figure 6-32.
4. Remove and discard the copper gaskets from all reusable spark plugs.
WARNING
Do not install any spark plug that has dropped or exhibits
physical damage.
5. If a new spark plug is required, select one from the list in Table 6-9.
FINE WIRE ELECTRODE MASSIVE ELECTRODE

NORMAL ELECTRODE CONDITION

•INSULATOR TIP GRAY, TAN OR LIGHT BROWN
•FEW COMBUSTION DEPOSITS
•ELECTRODES NOT BURNED OR ERODED
•PROPER TYPE AND HEAT RANGE PLUG FOR
ENGINE AND SERVICE.
•SPARK PLUG SHOULD BE CLEANED, REGAPPED
AND TESTED BEFORE REINSTALLTION

NORMAL WORN-OUT CONDITION

•ELECTRODES ERODED BY HIGH VOLTAGE

SPARKING AND BY CORROSIVE GASES
FORMED DURING COMBUSTION TO LESS THAN
1/2 ORIGINAL THICKNESS
•MORE VOLTAGE NEEDED TO FIRE SPARK
PLUGS - OFTEN MORE THAN IGNITION
SYSTEM CAN PRODUCE.
•REPLACE WITH NEW APPROVED AVIATION
SPARK PLUGS.

SEVERE WORN-OUT CONDITION

•EXCESSIVELY ERODED CENTER AND GROUND

ELECTRODES PLUS EXTENSIVE NECKING OF
FINE WIRE GROUND ELECTRODES INDICATE
ABNORMAL ENGINE POWER OR PLUGS
LONG OVERDUE FOR REPLACEMENT.
•DISCARD SPARK PLUGS AND CHECK HEAT
RANGE BEFORE INSTALLING NEW ONES.
•REPLACE WITH NEW APPROVED AVIATION
SPARK PLUGS IN APPROPRIATE HEAT RANGE.

Figure 6-32. Spark Plug Inspection Criteria

6. Clean the spark plugs (new or re-used) according to the manufacturer’s
recommendations. Set the spark plug gap to the spark plug manufacturer’s
recommended setting for the spark plug part number. If the manufacturer’s
recommended spark plug gap cannot be located, use the gap specified in Table 6-9.

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 A-80

E-225
A-100

O-470-2
IO-346-A
IOF-240-B

IO-360-AF
A-65; A-75
A-40; A-50

IO-240-A,B

E-165; E-185
C-115; C-125
Engine Model

15 Sep 2019
C-75; C-85; C-90

O-200-A,B,C,D,X

GO-300-A,B,C,D,E,F

JB,KB,LB,MB,RB,SB
C-145; O-300-A,B,C,D

IO-360-A,AB,C,CB,D,DB,
ES,G,GB,H,HB,J,JB,K,KB

D,DB,E,EB,F,FB,G,GB,H,HB,
L/TSIO-360-A,AB,B,BB,C,CB,
Electrode Barrel Continental
Gap Size/ Part Manufacturer 
(recommended) Reach1 Number Part Number

X
X
X
X
X
.016-.021 5/8-24S 656082 UREM37BY

X
X
X
X
.016-.021 5/8-24S 655902 UREM38E

X
X
X
X
.016-.021 5/8-24S 655899 UREM40E

Standard Practice Maintenance Manual

X
X X X X
X X X X
X
X
X X X
X
X X X X
X X X
X X X X
X X X X
.016-.021 3/4-20S 655915 URHM38E

X
.016-.021 3/4-20L 658565 URHM38EL

X
X
X
.017-.020 3/4-20S 658475 URHM38S

X X
X X
X X
X X
X X
X X
X X
X X
X
X X
X
.016-.021 3/4-20S 655914 URHM40E
Tempest Aviation

.017-.020 3/4-20L 658474 URHB32S

.016.-.021 3/4-20L 655908 URHB32E

X
.016-.021 UNSHLD N/A M41E

X X
X X
X X
X X
X X
X X
X X

.016-.021 5/8-24S N/A REM37BY

X
.016-.021 5/8-24S N/A REM38E

X X
X X
X X
.016-.021 5/8-24S N/A REM38S
Table 6-9. Spark Plug Application Chart

X X
X X X X X
X X
X X
X X
X
X X
X

.016-.021 5/8-24S N/A REM40E

X
.016-.021 3/4-20S N/A RHM38E

X X
X X
X X
.016-.021 3/4-20S N/A RHM38S

X X
X X X X X X X X
X X X X X X
X X X X X X X
X X
X X
X X
X X
X
X X
X

.016-.021 3/4-20S N/A RHM40E

.016-.021 3/4-20L N/A RHB32E
.016-.021 3/4-20L N/A RHB32S
Champion Aerospace

.016-.021 3/4-20L N/A RHB36S

.016-.021 3/4-20XL N/A RHU27E
.016-.021 3/4-20XL N/A RHU32E
.016-.021 3/4-20XL N/A RHU32S
Engine Inspection and Service

6-63
Engine Inspection and Service
Table 6-9. Spark Plug Application Chart
Tempest Aviation Champion Aerospace

Manufacturer 

656082 UREM37BY

URHM38EL
Number Part Number

URHM38E

URHM38S
URHM40E
UREM38E
UREM40E

REM37BY
URHB32S
URHB32E

RHM38E
RHM38S
RHM40E
REM38E
REM38S
REM40E

RHU27E
RHU32E
RHU32S
RHB32E
RHB32S
RHB36S
M41E
Continental

655902
655899
655915
658565
658475
655914
658474
655908
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
Part

.016-.021 UNSHLD

.016-.021 3/4-20XL
.016-.021 3/4-20XL
.016-.021 3/4-20XL
.016-.021 5/8-24S
5/8-24S
5/8-24S
3/4-20S

3/4-20S
3/4-20S

5/8-24S
5/8-24S
5/8-24S
5/8-24S
3/4-20S
3/4-20S
3/4-20S
3/4-20L

3/4-20L
3/4-20L

3/4-20L
3/4-20L
3/4-20L
Reach1
Barrel
Size/
(recommended)

.016.-.021
.016-.021
.016-.021
.016-.021
.016-.021
.017-.020
.016-.021
.017-.020

.016-.021
.016-.021
.016-.021
.016-.021
.016-.021
.016-.021
.016-.021
.016-.021
.016-.021
.016-.021
Electrode
Gap

Engine Model
O-470-4,11,13,13A,15 X X X X X X X X X X

O-470-A,E,J,K,L,R,S X X X X X X X X X

O-470-B,G,H,M,N,P X X X X X X X X X X X

O-470-U,T; X X X X X
IO-470-D,E,F,H,L,M,N,S,U,V

IO-470-C,G,R,P,T X X X X X X X X X X X

IO-470-J,K X X X X X X X X X X X

GIO-470-A X X X X X

TSIO-470-B,C,D X X X X X

GTSIO-520-,D,F,G,H,K,L,M,N X X X X X

IO-520-A,B,BA,BB,C,CB,D,F,J,K,L, X X X X X
M,MB,N,NB; L/IO-520-P

L/TSIO-520-B,C,D,DB,E,EB,G,H,J,JB,
K,KB,L,LB,M,N,NB,P,R,T,U,UB,VB, X X X X X
WB,AE,BE,CE

IO-550-A,B,C,D,E,F,L,N,P,R X X X X X

IOF-550-B,C,D,E,F,L,N,P,R X X X X X

TSIO-550-A,B,C,E,G, K, N X X X X X

TSIOF-550-D,J,K X X X X X

TSIOL-550-A,B,C X X

1. Spark plug reach is the distance from the shell gasket to the end of the shell threads. Shell reach is designated as Short, Long or Extra
Long, denoted by an “S”, “L” or “XL” following the barrel size.

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 Engine Inspection and Service
CAUTION: Failure to install a new spark plug gasket on each spark
plug may result in incomplete sealing of the combustion chamber,
loss of spark plug heat transfer, spark plug overheating, possible
pre-ignition / detonation and internal engine damage
NOTE: For engines using spark plug thermocouples to report cylinder
head temperature, copper gaskets are not required.
7. Install new copper gaskets on all spark plugs.
8. Refer to the spark plug rotation chart (Table 6-10); mark serviceable spark plugs
with the respective “TO” cylinder number. For all remaining locations, replace with
a new spark plug.
Table 6-10. Spark Plug Rotation Chart

Six Cylinder Spark Plug Rotation Four Cylinder Spark Plug Rotation
FROM CYLINDER NUMBER TO CYLINDER NUMBER FROM CYLINDER NUMBER TO CYLINDER NUMBER
1 TOP 6 BOTTOM 1 TOP 4 BOTTOM
1 BOTTOM 6 TOP 1 BOTTOM 4 TOP
2 TOP 5 BOTTOM 2 TOP 3 BOTTOM
2 BOTTOM 5 TOP 2 BOTTOM 3 TOP
3 TOP 4 BOTTOM 3 TOP 2 BOTTOM
3 BOTTOM 4 TOP 3 BOTTOM 2 TOP
4 TOP 3 BOTTOM 4 TOP 1 BOTTOM
4 BOTTOM 3 TOP 4 BOTTOM 1 TOP
5 TOP 2 BOTTOM
5 BOTTOM 2 TOP
6 TOP 1 BOTTOM
6 BOTTOM 1 TOP

9. Sparingly apply the spark plug manufacturer’s recommended thread lubricant to all
except the first row of threads on the spark plug.
10. Thread each spark plug by hand into the engine cylinder head within one to two
threads of the gasket. If the spark plug cannot be easily turned, clean the cylinder or
spark plug threads.
11. Torque the spark plugs to 300-360 in. lbs. (ref: Appendix B) using a calibrated
torque wrench and six-point deep well socket.

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Engine Inspection and Service
6-4.9.3. Ignition Harness Maintenance
NOTE: The cable outlet plates are keyed to attach to the magneto in only
one position. No. 1 position marked on the magneto cover aligns with
Cylinder No. 1 spark plug firing position.
Procedure
1. Inspect the spark plug leads for chafing, heat damage, wear, and cracking. Replace
damaged cables, if repair kits are available or replace the harness.
2. Clean and spray the mating surfaces with MS-122AD spray before installing harness
on magneto.
3. Install and tighten three (Champion (Slick)) or four (Continental) screws around the
cable outlet plate alternately to seat the cover squarely on magneto. Torque the
screws to Appendix B specifications.
4. Refer to the aircraft manufacturer's instructions for specific ignition harness routing
instructions. Observe the following when installing the harness on an engine:
a. Support leads with the necessary clamps and cable ties to prevent whipping or
chafing action. Inter-cylinder baffles are fitted with nut plates to secure ignition
harness clamps.
b. Refer to the aircraft manufacturer’s instructions for routing the ignition through
baffling and cushion clamp placement; ensure the ignition harness is not routed
in close proximity to the exhaust system.
c. Wipe the spark plug lead connector clean using a lint-free cloth moistened with
isopropyl alcohol.
d. To prevent the sleeves from sticking and minimize twisting of the ferrule, coat
the insulating sleeves (see Figure 6-33) with MS-122AD spray.

Figure 6-33. Lubricate Ignition Wire with MS-122AD, only where shown
e. Route the ignition leads to the cylinder number and position found on the labels
on the loose end of the cable. If the labels are missing or unclear, refer to the
ignition harness routing illustrations (in Maintenance and Overhaul (or Overhaul)
Manual). Secure the ignition leads to the rocker covers using the ignition lead
cushion clamps and rocker cover screws.

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5. If the ignition harness includes elbow clamps, install the elbow clamps (Figure 6-34)
on the harnesses at the ferrule to prevent harness strain; secure with clamp and
screws and lock washers.

Figure 6-34. Elbow Kit Assembly

6. Verify the inside of the spark plug barrel is clean and dry.
7. Insert the spring-end of the lead into the spark plug barrel. While holding the lead
wire B-nut, firmly push the rubber insulator into the spark plug.
CAUTION: Hold ferrules while torquing or loosening spark plug
coupling nuts to protect against twisting the ignition cable.
8. Push the ferrule against the spark plug and turn the B-nut clockwise. Continue
turning the B-nut until it seats and is finger-tight. While holding the spark plug lead
ferrule stationary, torque the B-nut to Appendix B specifications.
9. If all maintenance is complete, perform an “Engine Operational Check” according
to the instructions in Section 6-4.7.

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6-4.10. Engine Adjustments
NOTE: Before performing any engine fuel system adjustment, verify the
aircraft fuel system and fuel pump are operating according to the aircraft
manufacturer's specifications and perform an “Engine Operational
Check” according to the instruction in Section 6-4.7.
NOTE: For turbocharged engines, Wastegate Controller Adjustment
(Section 6-4.10.3) may be required after an engine is installed, rebuilt,
serviced, or overhauled.
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
WARNING
The procedures listed herein apply to Continental fuel injected
engines in their original type design. For modified engine
designs, refer to the Supplemental Type Certificate holder
information and instructions.
6-4.10.1. Oil Pressure Adjustment
NOTE: Oil pressure on C-75, C-85, C-90, O-200, and O/IO/IOF-240
engine models is not adjustable. Replace the oil pressure relief valve
components on these engine if oil pressure is not within acceptable limits.
Procedure
1. Perform an “Oil Pump Operational Check” according to the instructions in
Section 6-4.7.3. Adjust oil pressure if the recorded pressure is not within the
specified limits.
NOTE: The engine oil temperature must be within normal operating
range (see primary ICA) before oil pressure adjustment.
2. Loosen the jam nut securing the oil pressure adjustment screw (see Figure 6-35 for
adjustment location).
3. Adjust oil pressure to maintain oil pressure (see “Engine Specifications” section of
Primary ICA (30-60 psi for most engines)) at cruise power RPM. To increase oil
pressure, turn the oil pressure adjusting screw (Figure 6-35) clockwise (CW). To
decrease oil pressure, turn the oil pressure adjusting screw counterclockwise (CCW).
NOTE: If the jam nut is a lock nut with nylon insert, safety wire is not
required on the jam nut.
4. Torque the jam nut to Appendix B specifications and safety wire (if required) the
jam nut according to instructions in Appendix C.

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 Engine Inspection and Service

IO/L/TSIO-360 Oil Pressure Adjustment

520/550 Permold Oil Pressure Adjustment 470/520/550 Sandcast Oil Pressure

Adjustment with Oil Screen
Figure 6-35. Oil Pressure Relief Valve Adjustment Screw Locations

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Engine Inspection and Service
6-4.10.2. Fuel System Adjustment
Procedure
Perform the “Fuel System Operational Check” according to instructions in Section 6-
4.7.4. Record operational check results on a copy of the “Engine Operational Checklist.”
Determine adjustment requirements according to results of the Operational Check and
make adjustments according to instructions in Section 6-4.10.2.1, Section 6-4.10.2.2, or
Section 6-4.10.2.3 applicable to the engine model.
WARNING
Make all adjustments with the engine stopped and the Ignition
Switch and Master Power Switch in the OFF position!
6-4.10.2.1. Naturally Aspirated Engine Standard Fuel Pump Adjustments
Procedure
1. Unmetered Fuel Pump Pressure:
a. Loosen the jam nut on the fuel pump low pressure relief valve assembly (Figure
6-36 or Figure 6-37).
b. Turn the low pressure relief valve adjustment screw clockwise (CW) to increase
unmetered fuel pump pressure, or counter-clockwise (CCW) to decrease
unmetered fuel pump pressure.
NOTE: After each fuel system adjustment, restart the engine and operate
the engine at 1500 to 1800 rpm for 15 seconds to clear the engine, then
position throttle for desired checks.
c. Tighten the jam nut on the low pressure relief valve adjustment screw but do not
torque at this time; further adjustment may be required.
NOTE: Maximum part throttle full rich fuel flow will be achieved by
setting the idle RPM unmetered fuel pump pressure to the minimum value
specified. With the idle RPM fuel/air mixture properly adjusted
(after step 2, below), the fuel control metering plate orifices are
indexed to the maximum open position.
2. Idle Mixture Adjustment
a. Identify the illustration (Figure 6-38 or Figure 6-40) that matches the fuel system
being adjusted. Adjust the idle mixture setting to achieve the idle mixture rise
(Section 6-4.7.4, step 14) according to the direction depicted in the illustration.
Recheck the unmetered fuel pressure (Section 6-4.7.4, step 13) and idle mixture
rise (Section 6-4.7.4, step 14) and adjust, as necessary, until the fuel system
settings are adjusted within the specified limits.

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3. Full Power Metered Fuel Pressure Adjustment
WARNING
Wear eye protection when cutting safety wire to avoid injury
from flying debris.
a. If installed in an X-pattern through the adjustable orifice, cut and remove the
safety wire from the adjustable orifice housing (Figure 6-36 or Figure 6-37).
Adjust the safety wire routing through two adjacent sides of the housing and the
adjacent plug, next to the adjustable orifice housing on the fuel pump.
CAUTION: The adjustable orifice screw is a tapered needle and may
become damaged if forced against its seat. This adjustment should
move freely. Do not continue adjustments if rotational resistance
increases suddenly.
b. Turn the adjustable orifice screw clockwise (CW) to increase or
counterclockwise (CCW) to decrease metered fuel pressure.
4. Recheck unmetered fuel pump pressure, idle mixture rise, and full power metered
fuel pressure until all are within the specified limits (Section 6-4.7.1).
5. After final adjustments are complete, carefully torque the jam nut on the low
pressure relief valve to Appendix B specifications without disturbing the fuel system
adjustments. Do not exceed lock nut torque limits.
6. Recheck unmetered fuel pump pressure, idle mixture rise, and full power metered
fuel pressure to verify fastener torque did not affect fuel system adjustments. If
values are not within specified limits, repeat the adjustment procedures.
WARNING
Make all adjustments with the engine stopped and the Ignition
Switch and Master Power Switch in the OFF position!
NOTE: After each fuel system adjustment, restart the engine and operate
the engine at 1500 to 1800 rpm for 15 seconds to clear the engine, then
position throttle for desired checks.
7. IDLE RPM Adjustment
After adjusting fuel pressures to meet specifications, adjust the IDLE RPM to the
desired setting that provided smooth operation with minimal control adjustment for
ground operation. Do not adjust the IDLE setting below the minimum setting.
a. Turn the idle RPM adjustment screw until the end of the screw contacts the
throttle stop pin.
b. Turn the idle RPM adjustment screw clockwise (CW) to increase idle RPM or
counter-clockwise (CCW) to decrease idle RPM.
8. Upon completion of fuel system adjustments, return to Section 6-4.7.4, “Fuel
System Operational Check” to verify the fuel system adjustments meet the engine
model fuel system specifications.

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Engine Inspection and Service

Figure 6-36. Fuel Pump, Naturally Aspirated Engine without Integral Mixture Control

CAUTION: The adjustable orifice screw is a tapered needle and may

become damaged if forced against its seat. This adjustment should
move freely. Do not continue adjustments if rotational resistance
increases suddenly.

Figure 6-37. Fuel Pump, Naturally Aspirated Engine with Integral Mixture Control

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 Engine Inspection and Service

Figure 6-38. Throttle and Metering Assembly

Figure 6-39. Throttle and Control Assembly, Front View

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Engine Inspection and Service

Figure 6-40. Throttle and Control Assembly, Side View

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 Engine Inspection and Service
6-4.10.2.2. Naturally Aspirated Engine with Altitude Compensating Fuel Pump
Adjustments
WARNING
Make all adjustments with the engine stopped and the Ignition
Switch and Master Power Switch in the OFF position!
NOTE: After each fuel system adjustment, restart the engine and operate
the engine at 1500 to 1800 rpm for 15 seconds to clear the engine, then
position throttle for desired checks.
Procedure
1. Unmetered Fuel Pump Pressure:
a. Loosen the jam nut on the fuel pump low pressure relief valve assembly (Figure
6-36 or Figure 6-37).
b. Turn the low pressure relief valve adjustment screw clockwise (CW) to increase
unmetered fuel pump pressure, or counter-clockwise (CCW) to decrease
unmetered fuel pump pressure.
c. Tighten the jam nut on the low pressure relief valve adjustment screw but do not
torque at this time; further adjustment may be required.
NOTE: Maximum part throttle full rich fuel flow will be achieved by
setting the idle RPM unmetered fuel pump pressure to the minimum value
specified. With the idle RPM fuel/air mixture properly adjusted
(after step 2, below), the fuel control metering plate orifices are
indexed to the maximum open position.
2. Idle Mixture Adjustment
a. Identify the illustration (Figure 6-38 or Figure 6-40) that matches the fuel system
being adjusted.
b. Adjust the idle mixture setting to achieve the idle mixture rise (Section 6-4.7.4,
step 14) according to the direction depicted in the illustration. Adjust the idle
mixture setting to achieve the idle mixture rise (Section 6-4.7.4, step 14)
according to the direction depicted in the illustration. Recheck the unmetered fuel
pressure (Section 6-4.7.4, step 13) and idle mixture rise (Section 6-4.7.4, step 14)
and adjust, as necessary, until the fuel system settings are adjusted within the
specified limits.
3. Full Power Metered Fuel Pressure Adjustment:
CAUTION: The adjustable orifice screw is a tapered needle valve
and may become damaged if forced against its seat. This adjustment
should move freely. Do not continue adjustments if rotational
resistance increases suddenly.
a. On naturally aspirated engines with an adjustable orifice screw (Figure 6-42),
turn the adjustable orifice screw clockwise (CW) to increase or counterclockwise
(CCW) to decrease metered fuel pressure.

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Engine Inspection and Service
b. On naturally aspirated engines without an adjustable orifice screw:
CAUTION: The aneroid adjustment screw has an extra fine thread;
exceeding jam nut torque will damage either the adjustable aneroid
stem or housing threads. Jam nut torque value is 25-30 inch pounds.
1) Loosen the aneroid adjustment screw jam nut (Figure 6-41).
2) Turn the aneroid adjustment screw counter-clockwise (CCW) to increase full
power, metered fuel pressure; turn the screw clockwise (CW) to decrease full
power metered fuel pressure.
4. Recheck unmetered fuel pump pressure, idle mixture rise, and full power metered
fuel pressure until all are within the specified limits (Section 6-4.7.1).
5. After final adjustments are complete, carefully torque the jam nut on the low
pressure relief valve to 25-30 in. lbs. without disturbing the fuel system adjustments.
Do not exceed jam nut torque limits.
6. Recheck unmetered fuel pump pressure, idle mixture rise, and full power metered
fuel pressure to verify fastener torque did not affect fuel system adjustments. If
values are not within specified limits, repeat adjustment procedures.
7. IDLE RPM Adjustment
After adjusting fuel pressures to meet specifications, adjust the IDLE RPM to the
desired setting that provided smooth operation with minimal control adjustment for
ground operation. Do not adjust the IDLE setting below the minimum setting.
a. Turn the idle RPM adjustment screw until the end of the screw contacts the
throttle stop pin.
b. Turn the idle RPM adjustment screw clockwise (CW) to increase idle RPM or
counter-clockwise (CCW) to decrease idle RPM.
8. Upon completion of fuel system adjustments, return to Section 6-4.7.4, “Fuel
System Operational Check” to verify the fuel system adjustments meet the engine
model fuel system specifications.

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Figure 6-41. Altitude Compensating Fuel Pump (Auto-Lean),

Naturally Aspirated Engine (without adjustable orifice)

Figure 6-42. Altitude Compensating Fuel Pump (Auto-Lean),

Naturally Aspirated Engine (with adjustable orifice)

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Engine Inspection and Service
6-4.10.2.3. Turbocharged Engine Fuel Pump Adjustments
WARNING
Make all adjustments with the engine stopped and the Ignition
Switch and Master Power Switch in the OFF position!
NOTE: After each fuel system adjustment, restart the engine and operate
the engine at 1500 to 1800 rpm for 15 seconds to clear the engine, then
position throttle for desired checks.
1. Unmetered Fuel Pump Pressure:
a. Loosen the jam nut on the fuel pump low pressure relief valve 
assembly (Figure 6-43 or Figure 6-44).
NOTE: Maximum part throttle full rich fuel flow will be achieved by
setting the idle RPM unmetered fuel pump pressure to the minimum value
specified. With the idle RPM fuel/air mixture properly adjusted
(after step 2, below), the fuel control metering plate orifices are
indexed to the maximum open position.

Figure 6-43. Aneroid Equipped Fuel Pump, Turbocharged Engine

Figure 6-44. Aneroid and Mixture Control Equipped Fuel Pump,

Turbocharged Engine

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b. Turn the low pressure relief valve adjustment screw clockwise (CW) to increase
unmetered fuel pump pressure, or counter-clockwise (CCW) to decrease
unmetered fuel pump pressure.
c. Tighten the jam nut on the low pressure relief valve adjustment screw but do not
torque at this time; further adjustment may be required.
2. Idle Mixture Adjustment
a. Identify the illustration (Figure 6-38 or Figure 6-40) that matches the fuel system
being adjusted. Adjust the idle mixture setting according to the direction depicted
in the illustration to achieve the idle mixture rise (Section 6-4.7.4, step 14).
Adjust the idle mixture setting to achieve the idle mixture rise (Section 6-4.7.4,
step 14) according to the direction depicted in the illustration. Recheck the
unmetered fuel pressure (Section 6-4.7.4, step 13) and idle mixture rise
(Section 6-4.7.4, step 14) and adjust, as necessary, until the fuel system settings
are adjusted within the specified limits.
3. Full Power Metered Fuel Pressure Adjustment
a. On turbocharged engines without a fuel pressure regulator, loosen the jam nut
(Figure 6-43 or Figure 6-44) on the aneroid adjustment screw.
1) Turn the aneroid adjustment screw counter-clockwise (CCW) to increase full
power, metered fuel pressure; turn the screw clockwise (CW) to decrease full
power metered fuel pressure.
2) Tighten the jam nut on the aneroid adjustment screw to secure the setting; do
not torque at this time.
b. On turbocharged engines equipped with a fuel pressure regulator, perform a final
adjustment to the FULL POWER metered fuel pressure and fuel flow:
NOTE: On turbocharged engines equipped with a fuel pressure regulator,
the FULL POWER metered fuel pressure and fuel flow must be adjusted
to five (5) percent higher than the maximum specified limit when
regulator is disconnected to ensure adequate part-throttle fuel flow.
1) Turn the aneroid adjustment screw counter-clockwise (CCW) to increase full
power, metered fuel pressure; turn the screw clockwise (CW) to decrease full
power metered fuel pressure.
2) Tighten the jam nut on the aneroid adjustment screw to secure the setting; do
not torque at this time.
3) Reconnect the fuel pressure regulator (Figure 6-45); torque connections to the
Appendix B specifications.
4) Loosen the jam nut on the regulator adjustment set screw.
5) Turn the regulator adjustment screw clockwise (CW) to increase or
counterclockwise (CCW) to decrease metered fuel pressure and fuel flow.
4. Recheck unmetered fuel pump pressure, idle mixture rise, and full power metered
fuel pressure until all are within the specified limits (Section 6-4.7.1).

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Engine Inspection and Service
5. After final adjustments are complete, carefully torque the jam nut on the low
pressure relief valve to 25-30 in. lbs. without disturbing the fuel system adjustments.
Do not exceed jam nut torque limits.
6. Recheck unmetered fuel pump pressure, idle mixture rise, and full power metered
fuel pressure to verify fastener torque did not affect fuel system adjustments. If
values are not within specified limits, repeat the adjustment procedures.
7. IDLE RPM Adjustment
After adjusting fuel pressures to meet specifications, adjust the IDLE RPM (Figure
6-38 or Figure 6-40) to the desired setting that provided smooth operation with
minimal control adjustment for ground operation. Do not adjust the IDLE setting
below the minimum IDLE RPM setting (Section 6-4.7.1) for the engine model.
a. Turn the idle RPM adjustment screw until the end of the screw contacts the
throttle stop pin.
b. Turn the idle RPM adjustment screw clockwise (CW) to increase idle RPM or
counter-clockwise (CCW) to decrease idle RPM.
8. Upon completion of fuel system adjustments, return to Section 6-4.7.4, “Fuel
System Operational Check” to verify the fuel system adjustments meet the engine
model fuel system specifications.

Figure 6-45. Fuel Pressure Regulator, Turbocharged Engine

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6-4.10.2.4. Fuel Pump Auto-Lean Schedule Adjustment
NOTE: Auto-leaning is a function of naturally aspirated engines equipped
with altitude compensating fuel pumps. Turbocharged engines with
aneroid fuel pumps react to upper deck pressure reference pressure, not
atmospheric pressure.
NOTE: On IO-550-A and C model engines, do not attempt to adjust the
auto-leaning schedule if the aircraft is at a field altitude greater than 1000
feet. On IO-550-B, D, E, F and L model engines, do not attempt to adjust
the auto-leaning schedule if the aircraft is at a field altitude greater than
3000 feet.
1. If not previously accomplished, perform an “Engine Operational Check”
(Section 6-4.7) and “Flight Check” (Section 7-2.4.2), and adjust, as required, to
meet the “Fuel Injection System Specifications” in Section 6-4.7.1.
CAUTION: The aneroid adjustment screw has an extra fine thread;
exceeding jam nut torque will damage either the adjustable aneroid
stem or housing threads. Jam nut torque value is 25-30 inch pounds.
2. Adjustments to the altitude compensating fuel pump aneroid adjustment screw will
result in a change to the auto-leaning schedule (see Figure 6-48 through Figure 6-
54). One complete revolution of the aneroid adjustment screw will increase or
decrease the auto-leaning schedule approximately 1000 feet. Make adjustment in
small increments to avoid drastic changes to fuel pump operating characteristics.
3. Turn the aneroid adjustment screw clockwise (CW) to decrease the altitude (move
horizontally to the left on the chart); turn the aneroid adjustment screw
counterclockwise (CCW) to increase the altitude (moves horizontally to the right on
the chart) at a given pressure altitude.
4. Adjustments to the aneroid may affect the full power unmetered fuel pressure,
metered pressure, fuel mixture, and fuel flow. It is important to maintain the
balance between these adjustments in order to achieve the specified fuel system
parameters. Further re-adjustment of the adjustable orifice (metered fuel pressure
adjustment in Section 6-4.10.2) may be necessary after setting the auto-leaning
schedule.
CAUTION: The adjustable orifice screw is a tapered needle and may
become damaged if forced against its seat. This adjustment should
move freely. Do not continue adjustments if rotational resistance
increases suddenly.
5. If fuel flow on the chart is too lean or too rich, fine adjustments to the adjustable
orifice (see Figure 6-42) will correct vertical offset errors on the chart (Figure 6-46),
by increasing or decreasing fuel flow.
6. Review the Flight Check portion of the “Engine Operational Checklist” to determine
if the auto-leaning schedule is set to the “specified limits” for the engine model
(reference Table 6-17 and Figure 6-54 for IO-550-D engine model). Use the
following example to correct altitude offset errors and set the auto-leaning schedule:

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a. The plotted engine performance depicted by the black stars in Figure 6-46 begins
within the lower limit of the engine operating range, drifts below the minimum
fuel flow, and returns to near the lower limit of the operating range in the chart.
NOTE: Aneroid adjustments move the plotted performance horizontally
across the chart.
b. The goal, during adjustment, is to reposition the plotted performance as close to
the optimum fuel flow (represented by the dashed line) across the fuel pump
specifications in the chart (the midpoint between the upper and lower fuel flow
limits, according to Table 6-17).
c. Select a point along the plotted performance curve. In this example, we will use
4000 feet, as point “A”. In order to make the fuel pump conform to the
performance curve, we move horizontally across the chart to the midpoint
between the upper and lower limits on the target curve, called point “B” (see
Figure 6-46).
d. The horizontal distance between points “A” and “B” is 2000 ft. This value
represents the ALTITUDE OFFSET ERROR (Figure 6-46).
NOTE: Rotating the aneroid adjustment screw (increase/decrease)
corrects the altitude offset in the altitude leaning schedule.

Figure 6-46. Altitude Leaning Schedule Adjustment Example

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e. To achieve the correct altitude offset, rotate the aneroid adjustment screw one
complete revolution counterclockwise for each 1000 ft of correction required.
Thus, to correct a 2000 ft offset requires rotating the aneroid adjustment screw
approximately two turns counterclockwise.
f. Torque the jam nut to 25-30 inch pounds after aneroid adjustment.

Figure 6-47. Altitude Leaning after Correction

7. Perform a complete ground run-up and verify the unmetered and metered pressures,
idle mixture rise, and fuel flows are within the limits specified for the pressure
altitude. If these parameters are not within the limits specified, make adjustments
according to the instructions in Section 6-4.10.2 to achieve the specified values.
8. Once the adjustments are complete, remove the test equipment in accordance with
the instructions in Section 6-4.7.6.
9. Perform a flight check according to instructions in Section 7-2.4.2.
10. Repeat procedures until the engine’s fuel injection system meets all specifications.

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6-4.10.2.5. Altitude Compensating Fuel System Auto-Leaning Schedules
Table 6-11. IO-360-D/DB Engine Altitude Leaning Schedule
Full Throttle RPM, Full Rich Mixture @ 2800 RPM
Fuel Flow Fuel Flow Metered Fuel
Pressure Altitude (lbs/hr) (gals/hr) Pressure PSID
(Set Altimeter at 29.92 in. Hg.) Min. Max. Min. Max. Min. Max.
Sea Level 102.9 112.9 17.5 19.2 16.0 18.8
1,000 98.4 108.4 16.8 18.5 15.0 17.8
2,000 94.1 104.1 16.0 17.7 14.1 16.8
3,000 90.0 100.0 15.3 17.0 13.3 15.9
4,000 86.1 96.1 14.7 16.4 12.6 15.1
5,000 82.3 92.3 14.0 15.7 11.9 14.4
6,000 78.8 88.8 13.4 15.1 11.3 13.7
8,000 72.2 82.2 12.3 14.0 10.2 12.5
10,000 66.4 76.4 11.3 13.0 9.3 11.5
12,000 61.3 71.3 10.4 12.1 8.6 10.7
14,000 56.9 66.9 9.7 11.4 8.0 10.0
16,000 53.3 63.3 9.1 10.8 7.5 9.5
Gasoline = 5.87 lbs per gallon @ 70 F.
IO-360-DB installed in T-41 aircraft, Refer to Cessna SL81-2, dated July 1981 for amplified instructions
120
Fuel - 100/100LL
Full Rich, 2700 RPM
Fuel Temp 70°
110

100

90
Fuel Flow (PPH)

80

70

60

50
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Pressure Altitude (X1000 ft)

Figure 6-48. IO-360-D/DB Altitude Leaning Schedule

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Table 6-12. IO-360-ES Engine Altitude Leaning Schedule
Full Throttle RPM, Full Rich Mixture @ 2800 RPM
Fuel Flow Fuel Flow Metered Fuel
Pressure Altitude (lbs/hr) (gals/hr) Pressure PSID
(Set Altimeter at 29.92 in. Hg.) Min. Max. Min. Max. Min. Max.
Sea Level 100.0 107.0 17.0 18.1 14.3 16.5
1,000 97.7 103.7 16.6 17.7 13.9 15.8
2,000 93.7 99.7 16.0 17.0 13.1 14.9
3,000 90.3 96.3 15.4 16.4 12.3 14.1
4,000 87.3 93.3 14.9 15.9 11.7 13.6
5,000 85.0 91.0 14.5 15.5 11.5 13.2
6,000 83.3 89.3 14.2 15.2 11.1 12.8
8,000 80.0 86.0 13.6 14.7 10.6 12.2
10,000 77.3 83.3 13.2 14.2 10.1 11.8
12,000 74.4 80.4 12.7 13.7 9.6 11.2
14,000 71.3 77.3 12.1 13.2 9.2 10.7
16,000 69.3 75.3 11.8 12.8 8.9 10.3
Gasoline = 5.87 lbs per gallon @ 70 F.
110

Fuel - 100/100LL
Full Rich, 2700 RPM
Fuel Temp 70°
100

90
Fuel Flow (PPH)

80

70

60

50
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Pressure Altitude (X1000 ft)

Figure 6-49. IO-360-ES Altitude Leaning Schedule

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Table 6-13. IO-360-ES (Cirrus SR20) Engine Altitude Leaning Schedule
Full Throttle RPM, Full Rich Mixture @ 2700 RPM
Fuel Flow Fuel Flow Metered Fuel
Pressure Altitude (lbs/hr) (gals/hr) Pressure PSID
(Set Altimeter at 29.92 in. Hg.) Min. Max. Min. Max. Min. Max.
Sea Level 96.0 102.0 16.4 17.4 13.8 15.5
1,000 94.5 99.7 16.0 17.0 13.3 15.0
2,000 89.5 95.7 15.3 16.3 12.5 14.2
3,000 86.3 92.3 14.7 15.7 11.9 13.5
4,000 83.3 89.3 14.2 15.2 11.4 13.0
5,000 81.0 87.0 13.8 14.8 11.0 12.5
6,000 79.3 85.3 13.5 14.5 10.7 12.2
8,000 76.0 82.0 12.9 14.0 10.2 11.7
10,000 73.3 79.3 12.5 13.5 9.7 11.2
12,000 70.4 76.4 12.0 13.0 9.3 10.7
14,000 67.3 73.3 11.5 12.5 8.8 10.2
16,000 65.3 71.3 11.1 12.1 8.6 9.9
Gasoline = 5.87 lbs per gallon @ 70 F.
110

Fuel - 100/100LL
Recommended Setup for
Full Rich, 2700 RPM
Cirrus SR20 Installation
Fuel Temp 70°
100 2700 RPM @ WOT

90
Fuel Flow (PPH)

80

70

60

50
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Pressure Altitude (X1000 ft)

Figure 6-50. IO-360-ES in Cirrus SR20 Altitude Leaning Schedule

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Table 6-14. IO-550-A Engine Altitude Leaning Schedule
Full Throttle RPM, Full Rich Mixture 300 BHP @ 2700 RPM
Fuel Flow Fuel Flow Metered Fuel
Pressure Altitude (lbs/hr) (gals/hr) Pressure PSID
(Set Altimeter at 29.92 in. Hg.) Min. Max. Min. Max. Min. Max.
Sea Level 142 150 24.2 25.6 16.5 17.2
1,000 141 149 24.0 25.4 16.3 17.1
2,000 138 146 23.5 24.9 15.9 16.6
3,000 133 141 22.6 24.0 15.1 15.7
4,000 128 136 21.8 23.2 14.3 14.9
5,000 123 131 21.0 22.3 13.6 14.1
6,000 120 128 20.4 21.8 13.2 13.7
8,000 113 121 19.2 20.6 12.3 12.7
10,000 108 116 18.4 19.8 11.6 12.1
12,000 103 111 17.5 18.9 11.0 11.4
14,000 98 106 16.7 18.1 10.4 10.7
Gasoline = 5.87 lbs per gallon @ 70 F.
160

Fuel - 100/100LL
Full Rich, 2700 RPM
Fuel Temp 70°
150

140

130
Fuel Flow (PPH)

120

110

100

90
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Pressure Altitude (X1000 ft)

Figure 6-51. IO-550-A Altitude Leaning Schedule

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Table 6-15. IO-550-B Engine Altitude Leaning Schedule
Full Throttle RPM, Full Rich Mixture 300 BHP @ 2700 RPM
Fuel Flow Fuel Flow Metered Fuel
Pressure Altitude (lbs/hr) (gals/hr) Pressure PSID
(Set Altimeter at 29.92 in. Hg.) Min. Max. Min. Max. Min. Max.
Sea Level 146 156 24.9 26.6 17.2 18.3
1,000 145.5 155.5 24.8 26.5 17.1 18.2
2,000 145 155 24.7 26.4 17.0 18.1
3,000 144 154 24.5 26.3 16.9 17.9
4,000 142 152 24.2 25.9 16.5 17.5
5,000 139 149 23.7 25.4 16.1 17.0
6,000 135.5 145.5 23.1 24.8 15.5 16.5
8,000 127 137 21.6 23.3 14.2 15.1
10,000 117 127 19.9 21.6 12.8 13.6
12,000 110 120 18.7 20.4 11.9 12.6
14,000 105 115 17.9 19.6 11.3 11.9
Gasoline = 5.87 lbs per gallon @ 70 F.
160

Fuel - 100/100LL
Full Rich, 2700 RPM
Fuel Temp 70°
150

140

130
Fuel Flow (PPH)

120

110

100

90
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Pressure Altitude (X1000 ft)

Figure 6-52. IO-550-B Altitude Leaning Schedule

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Table 6-16. IO-550-C Engine Altitude Leaning Schedule
Full Throttle RPM, Full Rich Mixture 300 BHP @ 2700 RPM
Fuel Flow Fuel Flow Metered Fuel
Pressure Altitude (lbs/hr) (gals/hr) Pressure PSID
(Set Altimeter at 29.92 in. Hg.) Min. Max. Min. Max. Min. Max.
Sea Level 152 160 25.9 27.2 18.2 18.9
1,000 151 159 25.7 27.1 18.0 18.7
2,000 148 156 25.2 26.6 17.5 18.2
3,000 143 151 24.4 25.7 16.7 17.4
4,000 138 146 23.5 24.9 15.9 16.5
5,000 134 142 22.8 24.2 15.3 15.9
6,000 130 138 22.1 23.5 14.7 15.3
8,000 123 131 21.0 22.3 13.6 14.1
10,000 118 126 20.1 21.5 12.9 13.4
12,000 113 121 19.3 20.6 12.3 12.7
14,000 108 116 18.4 19.8 11.7 12.1
Gasoline = 5.87 lbs per gallon @ 70 F.
170
Fuel - 100/100LL
Full Rich, 2700 RPM
Fuel Temp 70°
160

150

140
Fuel Flow (PPH)

130

120

110

100

90
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Pressure Altitude (X1000 ft)

Figure 6-53. IO-550-C Altitude Leaning Schedule

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Table 6-17. IO-550-D, E, F, & L Engine Altitude Leaning Schedule
Full Throttle Static RPM, Full Rich Mixture 300 BHP @ 2700 RPM
Fuel Flow Fuel Flow Metered Fuel
Pressure Altitude (lbs/hr) (gals/hr) Pressure PSID
(Set Altimeter at 29.92 in. Hg.) Min. Max. Min. Max. Min. Max.
Sea Level 143 155 24.4 26.4 17.2 20.0
1,000 142.5 154.5 24.3 26.3 17.1 19.9
2,000 142 154 24.2 26.2 17.0 19.8
3,000 141 153 24.0 26.1 16.9 19.6
4,000 139 151 23.7 25.7 16.5 19.2
5,000 136 148 23.2 25.2 16.0 18.7
6,000 133 145 22.6 24.7 15.5 18.2
8,000 124 136 21.1 23.2 14.0 16.6
10,000 114 126 19.4 21.5 12.5 15.0
12,000 107 119 18.2 20.3 11.5 13.9
14,000 102 114 17.4 19.4 10.8 13.1
Gasoline = 5.87 lbs per gallon @ 70 F.
160
Fuel - 100/100LL
Full Rich, 2700 RPM
Fuel Temp 70°
150

140

130
Fuel Flow (PPH)

120

110

100

90
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Pressure Altitude (X1000 ft)

Figure 6-54. IO-55-D, E, F & L Altitude Leaning Schedule

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6-4.10.3. Manifold Pressure Adjustment
Manifold pressure is based on ambient air pressure on naturally aspirated engines.
Manifold pressure on turbocharged engines is determined by the turbocharger to throttle
interface and varies by engine model. Consult the turbocharger and exhaust system
description in the primary ICA for a description of system functionality.
Some turbocharger system configurations are delivered with the engine, others are
coordinated with, developed by, and configuration controlled by the aircraft manufacturer.
For systems not depicted in this manual, refer to the primary ICA or the Aircraft
Maintenance Manual.
The following turbocharger and exhaust systems, or parts thereof, are provided by the
aircraft manufacturer:
See Aircraft Maintenance Manual for the following Engine
Models: 
GTSIO-520-C, D, H, K, L, M, N;
TSIO-360-A, AB, B, BB, C, CB, D, DB, H, HB, and JB; 
TSIO-470-B, C and D
TSIO-520-B, BB, C, D, DB, E, EB, G, H, J, JB, K, KB, M, N,
NB, P, R, AE, AF, CE, and VB; 
TSIO-550-C (select Cessna specifications)
TSIOL-550-A

6-4.10.3.1. Fixed Wastegate Adjustment

Applicable Engines: TSIO-360-E, EB, F, FB, G, GB, KB, LB;
LTSIO-360-E, EB, KB
Engine manifold pressure is controlled by a ground adjustable fixed wastegate on the
exhaust bypass pipe at the turbocharger location. This adjustment is preset and only minor
changes should be required.
Procedure
NOTE: Takeoff rated manifold pressure and RPM are obtained at
approximately 40% throttle travel
1. Loosen jam nut on adjustment bolt.
2. For initial setting at installation or replacement: Screw the adjustment bolt (Figure
6-55) clockwise (CW) to the fully seated position. Turn the adjustment bolt
counterclockwise (CCW) ten (10) turns and lock in position with the jam nut.
3. Run engine according to AFM/POH. Advance throttle to obtain rated manifold
pressure. Make fine adjustments required to meet the manifold pressure setting for
the engine model in Table 6-4, CW to increase, CCW to decrease.
4. Torque the jam nut on adjustment bolt after adjustments are complete. safety wire
the adjustment bolt to the adjacent anchor point after the jam nut final torque.

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Figure 6-55. Fixed Wastegate, typical

5. Check critical altitude during Flight Check (Section 7-2.4.2); if adjustment is
necessary:
NOTE: Take-off rated MP and RPM are obtained at approximately 40°
throttle travel.
NOTE: Adjusting the exhaust bypass is extremely important. This setting
determines Full Throttle manifold pressure and critical altitude and must
be properly adjusted before the fuel system can be set up accurately.
NOTE: Rated manifold pressure for a given altitude should be achieved
on take-off roll. If rated MAP cannot be obtained, check for exhaust
leaks, turbocharger condition or calibration of overboost valve.
NOTE: To check actual critical altitude, the aircraft must be flown. Refer
to Aircraft Service Manual for test flight procedures. If critical altitude is
not correct and fixed wastegate is readjusted, the metered fuel flow must
be rechecked and set to maximum power (full throttle) values.
6. Make adjustments, as necessary, to the fixed wastegate adjustment. Turning bolt
clockwise (CW) increases critical altitude, turning bolt counter-clockwise (CCW)
decreases critical altitude.
NOTE: One complete turn (360°) of the adjustment bolt changes the
critical altitude by approximately 1000 feet.
7. Torque the jam nut on adjustment bolt after adjustments are complete. safety wire
the adjustment bolt to the adjacent anchor point after the jam nut final torque.

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6-4.10.3.2. Fixed Orifice Wastegate Adjustment
Applicable Engines: TSIO-520-T
The fixed orifice wastegate is a ground adjustable bypass valve located in the turbine
exhaust bypass duct. The position of the fixed orifice wastegate valve remains constant
throughout all modes of engine operation. An overboost pressure relief valve is used with
the fixed orifice wastegate valve to bleed off upper deck pressure that exceeds the limits
set by the aircraft manufacturer.Early Model TSIO-520-T engines use an exhaust system
bypass valve similar to the one depicted in Figure 6-58, A. Current production engines use
an exhaust system bypass valve similar to the one depicted in Figure 6-58, B. The bypass
valve is installed in the exhaust system just forward and to the right of the turbocharger.
Procedure
1. Loosen jam nut on adjustment bolt.
2. If the installed exhaust system bypass resembles Figure 6-56, A:
a. Screw the adjustment bolt clockwise (CW) to the fully seated position. Turn the
adjustment bolt counterclockwise (CCW) two turns and lock in position with the
jam nut.
b. Run engine to check full throttle manifold pressure. Make fine adjustments
required to meet the performance curve in the primary ICA, CW to increase,
CCW to decrease.
3. If the installed exhaust system bypass resembles Figure 6-56, B:
a. Screw the adjustment bolt clockwise (CW) to the fully seated position. Turn the
adjustment bolt counterclockwise (CCW) eight and one-half (8½) turns and lock
in position with the jam nut.
b. Run engine to check full throttle manifold pressure. Make fine adjustments
required to meet the performance curve in the primary ICA, CW to increase,
CCW to decrease.
4. Torque the jam nut on adjustment bolt to Appendix B specifications and safety wire
when complete.

Figure 6-56. Fixed Wastegate (TSIO-520-T), typical

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6-4.10.3.3. Sloped Controller Adjustment
Applicable Engines: TSIO-520-BE; 
TSIO-550-A, B, C, E, G, K, N
TSIOL-550-C
CAUTION: Instructions in this section were verified on TSIO-550-C
engine models. For all other engine models, consult the Aircraft
Maintenance Manual before proceeding.
The sloped controller limits oil flow through the wastegate, which determines the position
of the butterfly valve in the wastegate. Adjustment of the sloped controller may be
required after an engine is installed, rebuilt, serviced, or overhauled, or sloped controller
replacement.
Procedure
1. Orient the aircraft nose into the prevailing wind and run the engine at 1500 to 1800
RPM until the oil temperature is 160 to 180° F (71 to 82°C).
2. Using a handheld digital tachometer set the propeller controls according to the
Section 6-4.7.1.
3. With the throttle in the FULL FORWARD position, set the intake manifold pressure
according to the value in Section 6-4.7.1 for the engine model by turning the
adjusting screw on the bottom of the slope controller (Figure 6-57) using a wide
blade common screwdriver. Turning the screw clockwise (CW) increases manifold
pressure, counter-clockwise (CCW) decreases manifold pressure.
NOTE: 1/8 turn of the adjusting screw = @1.0 inch Hg.

Figure 6-57. Sloped Controller, typical

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6-4.10.3.4. Variable Absolute Pressure Controller Adjustment
Applicable Engines: TSIO-360-MB, RB, SB; LTSIO-360-RB;
TSIO-520-L, LB, N, NB, UB, and WB;
The Variable Absolute Pressure Controller (VAPC) limits oil flow through the wastegate,
which determines the position of the butterfly valve in the wastegate. Adjustment of the
VAPC may be required after an engine is installed, rebuilt, serviced, or overhauled or if
the VAPC is replaced.
Procedure
1. Orient the aircraft nose into the prevailing wind and run the engine at 1500 to 1800
RPM until the oil temperature is 160 to 180° F (71 to 82°C).
2. Using a hand held digital tachometer, set the propeller controls 
according to Table 6-18.
3. With the throttle in the FULL FORWARD position, set the intake manifold pressure
according to the value in Table 6-18 for the engine model by turning the HIGH
SETING adjusting screw on the VAPC (Figure 6-58). Turning the screw clockwise
(CW) decreases manifold pressure, counter-clockwise (CCW) increases manifold
pressure.
NOTE: One complete turn (360°) of the adjusting screw = @1.0 inch Hg
manifold pressure.
Table 6-18. VAPC Parameters
L/TSIO-360- TSIO-520-LB
Parameter TSIO-360-MB RB TSIO-360-SB TSIO-520-NB TSIO-520-UB TSIO-520-WB

Propeller Controls 2700 RPM 2600 RPM 2600 RPM 2700 RPM 2700 RPM 2700 RPM

Rated Manifold Air Pressure 36.0 in. Hg 38.0 in. Hg 39.0 in. Hg 38.0 in. Hg 36.0 in. Hg 39.5 in. Hg
(Full throttle @ sea level) ±0.2 in. Hg

Figure 6-58. Variable Absolute Pressure Controller

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6-4.10.4. Belt Tension Check and Adjustment
Some Continental engines may be fitted with an optional belt driven air conditioning
compressor or belt driven alternator. Belt tension is critical to the function of these
optional devices however; a new belt will stretch and tension will loosen during the break-
in period after installation. Check the belt tension after the break-in period and during
subsequent visual inspections.
6-4.10.4.1. Air Conditioning Compressor Drive Belt Tension Check and Adjustment
Applicable Engines: IO & L/TSIO-520; IO, IOF, TSIO & 
TSIOF-550 Permold Series Engines
Procedure
1. Inspect the drive belt for obvious signs of wear, nicks, or cracks; replace if
necessary.
2. Check the belt tension at the point indicated in Figure 6-59 with a direct reading
tension gauge (50 to 70 pounds) or measure belt deflection with a five pound load at
the center of the longest belt span for 0.30 to 0.40 inches of deflection. If deflection
is within tolerance, document the inspection results. To adjust belt tension, proceed
to the next step.
NOTE: One full turn of the adjusting screw yields approximately 10
pounds change in tension.
3. Loosen the jam nut on the idler pulley. Tighten the adjusting bolt to increase tension,
loosen the adjusting bolt reduce tension. When properly adjusted, secure the
adjusting bolt with the jam nut and torque according to Appendix B specifications.

COMPRESSOR
BRACKET ASSEMBLY

JAM NUT
ADJUSTING BOLT
MEASURE BELT
DEFLECTION HERE

COMPRESSOR
(AIRFRAME SUPPLIED)

DRIVE BELT
DRIVER SHEAVE SLIDE NUT

Figure 6-59. Air Conditioning Compressor Belt Tensioning

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6-4.10.4.2. Air Conditioning Compressor Drive Belt Tension Check and Adjustment
Applicable Engines: IO and L/TSIO-360 Series Engines
Procedure
1. Inspect the drive belt for obvious signs of wear, nicks, or cracks; replace if
necessary.
2. Check the belt tension at the center of the span between the drive sheave and the
compressor with a Direct Reading Tension Gauge (Ideal Aviation BT-33-73FIA in
Section 3) for 45 to 50 pounds (18 to 23 Kg) of belt tension. If tension is within
tolerance, document the inspection results. To adjust belt tension, proceed to the
next step.
3. To adjust belt tension for optional rear mounted compressor, do the following:
a. Loosen the adjustment bolt (Figure 6-60, item 5) securing the compressor (10) to
the top of the rear adjustment bracket (1).
b. Loosen the mounting bolt (4), washers (2), and nut (3) at the bottom of the rear
adjustment bracket (1) to allow the compressor (10) to pivot.
c. Adjust the belt (8) tension and tighten the adjustment bolt (5). Torque the
adjustment bolt (5) to Appendix B specifications.
d. Torque the mounting bolt (4) and nut (3) to Appendix B specifications.

Figure 6-60. Optional Compressor Belt Tensioning, typical

1 Rear Bracket Assembly 4 Bolt 7 Washer 10 Compressor
2 Washer 5 Bolt 8 V-belt
3 Nut 6 Lock Washer 9 Front Bracket Assembly

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Engine Inspection and Service
6-4.10.4.3. Alternator Drive Belt Tension Check and Adjustment
Applicable Engines: IO & L/TSIO-520; IO, IOF, TSIO & 
TSIOF-550 Permold Series Engines with 70 amp alternator
Procedure
1. Inspect the drive belt for obvious signs of wear, nicks, or cracks; replace if
necessary.
2. Inspect the bracket, brace, and associated hardware for cracks or physical damage;
replace if necessary.
3. Check the belt tension at the center of the span between the drive sheave and the
alternator with a Direct Reading Tension Gauge (BT-33-73FIA) for 0.11 inch
deflection with 6-8 pounds of belt tension applied. If deflection is within tolerance,
document the inspection results. To adjust belt tension, proceed to the next step.
4. Loosen the upper bolt (Figure 6-61, item 4), washer (2) and nut (3) securing the
alternator (12) to the bracket (1).
5. Loosen the pivot screw (9) securing the alternator (12) to the adjustable brace (10).
6. Remove the safety wire and loosen the screw (5) at the bottom of the adjustable
brace (10).
7. Adjust the belt tension until deflection is 0.11 inch with 6-8 pounds of belt tension
applied and tighten the adjustment screw (5). Torque the adjustment screw to
Appendix B specifications.
8. Torque the mounting bolt (3) and pivot screw (9) to Appendix B specifications.
Safety wire the adjustment screw (5) to a nearby through bolt according to Appendix
C specifications.

Figure 6-61. Alternator Belt Tensioning

1 Bracket Assembly 4 Bolt 7 Washer 10 Adjustment Brace
2 Washer 5 Bolt 8 Bracket 11 V-belt
3 Nut 6 Lock Washer 9 Bolt 12 Alternator Assembly

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6-4.10.4.4. Alternator Drive Belt Tension Check and Adjustment
Applicable Engines: IO & L/TSIO-520; IO, IOF, TSIO & 
TSIOF-550 Permold Series Engines with 85 amp alternator
Procedure
1. Inspect the drive belt for obvious signs of wear, nicks, or cracks; replace if
necessary.
2. Inspect the bracket, brace, and associated hardware for cracks or physical damage;
replace if necessary.
3. Check the belt tension at the center of the span between the drive sheave and the
alternator for 3.2 to 4.4 pounds of tension at 0.11 inch deflection or with a Direct
Reading Tension Gauge (BT-33-73FIA) for 50-70 pounds of belt tension. If
deflection is within tolerance, document the inspection results. To adjust belt
tension, proceed to the next step.
4. Loosen the adjustment screw (Figure 6-62, item 8) securing the alternator (10) to the
adjustment brace (11).
5. Loosen the alternator mounting bolt (4) and nut (3) at the top of the bracket (1) to
allow the alternator (10) to rotate.
6. Remove the safety wire and loosen the pivot screw (5) at the bottom of the alternator
bracket (1).
7. Adjust the belt tension until deflection is 0.11 inch at 3.2 to 4.4 pounds of tension
and tighten the adjustment screw (8). Torque the adjustment screw (8) to Appendix
B specifications.
8. Torque the alternator mounting bolt (4) and pivot screw (5) to Appendix B
specifications. Safety wire the pivot screw (5) to the hole drilled in the adjustment
brace according to Appendix C instructions.

Figure 6-62. 85 Amp Alternator Belt Adjustment

1 Bracket Assembly 4 Bolt 7 Lock Washer 10 Alternator Assembly
2 Washer 5 Screw 8 Screw 11 Adjustment Brace
3 Nut 6 Lock Washer 9 Washer 12 V-belt

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6-4.10.4.5. Alternator Drive Belt Tension Check and Adjustment
Applicable Engines: IO & L/TSIO-360 with front mount belt
driven alternator
Procedure
1. Inspect the drive belt for obvious signs of wear, nicks, or cracks; replace if
necessary.
2. Inspect the bracket, brace, and associated hardware for cracks or physical damage;
replace if necessary.
3. Check the belt tension at the center of the span between the drive sheave and the
alternator with a Direct Reading Tension Gauge (BT-33-73FIA) for 45-50 pounds of
belt tension. If tension is within tolerance, document the inspection results.
4. To adjust belt tension, do the following:
a. Loosen the bolt (Figure 6-63, item 5) securing the alternator (12) to the
adjustment brace (10).
b. Loosen the pivot bolt (9) and lock nut (15) at the bottom of the bracket (1).
c. Loosen the mounting bolt (4), and nut (3) at the top of the bracket (1) to allow the
alternator (12) to pivot.
d. Adjust the belt (11) tension and tighten the bolt (5). Torque the bolt (5) to
Appendix B specifications.
e. Torque the mounting bolt (4), nut (3), lock nut (15) and pivot bolt (9) to
Appendix B specifications.

Figure 6-63. Front Mount Belt Driven Alternator

1 Bracket Assembly 5 Bolt 9 Bolt 13 Spacer
2 Washer 6 Lock Washer 10 Adjustment Brace 14 Washer
3 Nut 7 Washer 11 V-belt 15 Lock Nut
4 Bolt 8 Washer 12 Alternator

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6-4.10.4.6. Alternator Drive Belt Tension Check and Adjustment
Applicable Engines: IO & L/TSIO-360 with aft mount belt
driven alternator
Procedure
1. Inspect the drive belt for obvious signs of wear, nicks, or cracks; replace if
necessary.
2. Inspect the bracket, brace, and associated hardware for cracks or physical damage;
replace if necessary.
3. Check the belt tension at the center of the span between the drive sheave and the
alternator with a Direct Reading Tension Gauge (BT-33-73FIA) for 45-50 pounds of
belt tension. If tension is within tolerance, document the inspection results.
4. To adjust belt tension, do the following:
a. Loosen the adjustment bolt (Figure 6-64, item 5) securing the alternator (10) to
the top of the rear adjustment bracket (1).
b. Loosen the mounting bolt (4), washers (2), and nut (3) at the bottom of the rear
adjustment bracket (1) to allow the alternator (10) to pivot.
c. Adjust the belt (8) tension and tighten the adjustment bolt (5). Torque the
adjustment bolt (5) to Appendix B specifications.
d. Torque the mounting bolt (4) and nut (3) to Appendix B specifications

Figure 6-64. Aft Mounted Alternator Belt Tension Adjustment

1 Rear Bracket Assembly 4 Bolt 7 Washer 10 Alternator
2 Washer 5 Bolt 8 V-belt
3 Nut 6 Lock Washer 9 Front Bracket Assembly

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6-4.11. Cylinder Inspections
A complete cylinder inspection entails the tasks described in the respective sections
Table 6-19 below. Performing all of the tasks in Table 6-19 ensures items that can affect
cylinder operation have been inspected and verified for proper operation. Use a copy of
the “Cylinder Inspection Checklist” on page 6-177 to record inspection progress and
findings.

Table 6-19. Cylinder Inspection Tasks and References

Task1 Section Reference

Cylinder visual inspection Section 6-4.11.1
Check cylinder differential pressure Section 6-4.11.2
Inspect engine cylinders with borescope Section 6-4.11.3
Inspect cylinder to crankcase mounting deck Section 6-4.11.4
Inspect baffles Section 6-4.11.5
Inspect cowling Section 6-4.11.6
1. All tasks in this table must be performed for a complete cylinder inspection.

In addition to the instructions contained in this section, reference the following Service
Documents to determine compliance requirements, based on engine model applicability.
Table 6-20. Additional Cylinder Service Document References
Document Number Title
M92-8 Application of 4 -1/16 inch Diameter Cylinder Assemblies
M92-6 Rocker Shaft Retention Improvement for Inclined Valve Cylinder
M92-4 IO & L/TSIO-360 Rocker Shaft Stud Inspection
M91-7 Cylinder Barrel Ultrasonic Inspection
M91-6 Cylinder Barrel Inspection
M73-13 Rocker Shaft Bosses
M73-2 Cylinder, Non - H FAA AD #72-20-02

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6-4.11.1. Cylinder Visual Inspection
Procedure
1. Remove the engine compartment cowling according to the aircraft manufacturer’s
instructions and perform steps 2 & 3 without cleaning the engine.
2. Inspect the cylinder barrel power stroke areas (Figure 6-65) with an inspection
mirror and light for cracks, sharp indentations, chafing, damage or pitting. Repair
discrepancies according to instructions in the primary ICA. The power stroke areas
include the:
• Twelve o’clock area on the first six fins below the head on the 1-3-5 side of the
engine as mounted on the crankcase.
• Six o’clock area on the first six fins below the head on the 2-4-6 side of the
engine as mounted on the crankcase.
3. Inspect the external surfaces of the cylinder head including the fins, intake and
exhaust ports, top and bottom spark plug bosses and fuel nozzle bosses for cracks,
exhaust flange leakage or any signs of oil, fuel, or soot leakage indicating cylinder
or the head-to-barrel junction structural integrity breach.
Minor cylinder repairs may be accomplished using the instructions in the applicable
primary ICA; however,
a. replace any cylinder exhibiting cracks or a structural integrity breach.
b. additionally, for liquid cooled cylinders, inspect the cylinder head cooling jackets
for coolant leaks.
4. Thoroughly clean the exterior of the engine according to instructions in Chapter 12
and repeat steps 2 & 3.

1-3-5 CYLINDER
POWER STROKE STRESS AREA

2-4-6 CYLINDER
POWER STROKE STRESS AREA
Figure 6-65. Cylinder Power Stroke Areas

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For all -470, -520, and -550 series engines only:
CAUTION: Reference the latest version of Service Document (SB18-
04) for replacement instructions of through-bolt flange nuts (P/N
652541) identified with the manufacturer’s stamp “ZB” (purchased
after 1 OCT 2017).
NOTE: The following steps supersede SB17-01A, “Flanged Nut (P/N
652541) Inspection and Corrosion Prevention.”
5. Visually inspect the 1/2” through-bolt flanged nuts (P/N 652541) for corrosion.
a. If flanged nuts exhibit no signs of damage or corrosion, proceed to step 6.
b. If the crankcase hardware exhibits corrosion, replace the crankcase hardware
(one nut at a time) according to the primary ICA crankcase hardware installation
instructions.
c. If a flanged nut exhibits a fracture, remove the engine from service and perform
an inspection for possible bearing shift according to the primary ICA.
6. Thoroughly clean the crankcase hardware with mineral spirits to remove any
residual corrosion inhibitor.
CAUTION: When utilizing compressed air, wear OSHA approved
protective eye wear. Never exceed 30 psi when using compressed
gases for cleaning purposes (OSHA 1910.242(b)).
7. Completely dry crankcase hardware with compressed air.
8. Apply a single, light coating of LPS® Procyon (or LPS 3®) heavy duty corrosion
inhibitor to the through-bolts, washers, and (Part No. 652541) flanged nuts
according to the manufacturer’s directions and Safety Data Sheet (SDS).
9. Create a log book entry indicating compliance with the flanged nut inspection.

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6-4.11.2. Differential Pressure Test
Purpose
The Cylinder Differential Pressure Test is a nondestructive method of determining the
internal condition of cylinders and cylinder components. As with any test or inspection,
the Cylinder Differential Pressure Test has certain limitations that may necessitate its use
in conjunction with other non-invasive inspections. The Cylinder Differential Pressure
Test identifies leaks and the source of leaks, with the engine under static conditions (not
running), using a regulated 80 psi pressure source. The Cylinder Borescope Inspection
(Section 6-4.11.3) is used to assess the physical condition of the combustion chamber.
Continental requires a borescope inspection to be performed in conjunction with the
Differential Pressure Test. Marginal or unsatisfactory results of the Cylinder Differential
Pressure Test or Cylinder Borescope inspections may indicate the need to perform
additional inspections.
NOTE: The static leak check does not relate directly to cylinder pressures
developed during actual engine operations.
Monitor and record engine oil consumption, the appearance or color of the engine oil and
any visual indications of high crankcase pressure (combustion blow-by) such as an oily,
wet area on the aircraft belly or lower wing surface.
NOTE: Prior to performing the cylinder differential pressure test,
determine the baseline master orifice calibrated pressure reading
according to instructions in Section 6-4.11.2.1.
Excess cylinder wall or piston ring wear, broken piston rings and burned valves exhibit
additional symptoms that include, but are not limited to the following:
• Excessive cylinder barrel wear and/or piston ring wear:
• Elevated crankcase pressure; see “Excess Crankcase Pressure” in Section 8-9.1.
• Sudden increased oil consumption (based on trend monitoring)
• Oil discolored within first 10 hours after an oil change
• Broken piston rings:
• Scored, grooved cylinder wall, evident via a borescope inspection
• Abnormal debris in oil filter or oil screen
• Burned valves:
• Extremely low cylinder differential pressure test results
• Usually evident during borescope inspection.
Many variables affect Differential Pressure Test results, such as:
• Abnormal amounts of oil in the cylinder
• Engine temperature and cylinder temperature uniformity
• Test equipment accuracy
• Capacity and quality of the compressed air source
• Techniques used by the technician when performing the test

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Frequency
Perform the differential pressure test:
• During 100-hour or Annual inspections
• If excessive oil consumption or blow-by is suspected
• If the cylinder exhibits signs of accelerated wear
Test Equipment
• Dry, oil-free compressed air source capable of providing a minimum line pressure of
125 P.S.I. with a minimum flow capability of 15 Cubic Feet per Minute (CFM).
NOTE: Master Orifice Tool (Part No. 646953A) is no longer available.
Without the Master Orifice Tool, the Model E2A Differential Pressure
Tester is not a valid test equipment option; the Model E2M Differential
Pressure Tester must be used. If the facility performing the repairs is in
possession of both a Model E2A Differential Pressure Tester and the
Master Orifice Tool, the shop may continue to use them as alternatives to
the Model E2M Differential Pressure Tester. Instructions in this manual
apply only to the Model E2M Differential Pressure Tester.

The Eastern Technology web site (eastertech.com) indicates a Model
E2M-1000, with a 0.060 Master Orifice should be used on cylinders with
a bore greater than 5.0 inches however, approved type certificate data
pertaining to engines in this manual were approved by the FAA using a
Model E2M Differential Pressure Tester with a 0.040 inch Master Orifice.
• Eastern Technology Corporation Model E2M (Figure 6-66) Cylinder Differential Pressure
Tester. This Differential Pressure Tester incorporates a 0.040 Master Orifice Tool.
WARNING
Differential Pressure Test equipment must be calibrated
annually. Failure to properly maintain and calibrate the
Differential Pressure Test equipment may result in misleading
or erroneous Differential Pressure Test readings.
Perform the “Differential Pressure Tester Setup” instructions in Section 6-4.11.2.1 to
calibrate the test equipment prior to conducting the Cylinder Differential Pressure Test.
Perform the Cylinder Differential Pressure Test as soon as possible after the aircraft has
returned from flight. If the aircraft cannot be flown prior to performing the Cylinder
Differential Pressure Test, operate it on the ground, with the cowling installed until a
minimum of 300 to 350°F (149 to 177°C) is observed on the aircraft cylinder head
temperature (CHT) gauge.
WARNING
Shut the fuel supply OFF and ground the magnetos prior to
performing the Differential Pressure Test to prevent accidental
engine starts. Take necessary precautions to prevent accidental
rotation of the propeller while performing this test. Differential
pressure tests are best performed with two people, one to adjust
the pressure regulator and one to hold the aircraft propeller.

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The “Master Orifice” is a calibration standard that must be used prior to performing the
Cylinder Differential Pressure Test. The Master Orifice establishes the acceptable cylinder
pressure leakage limit for the test equipment being used and the atmospheric conditions at
the time of the test. Record the acceptable cylinder pressure leakage limit, along with the
individual cylinder readings in the engine logbook and on a copy of “Cylinder Inspection
Checklist” on page 6-177.
6-4.11.2.1. Differential Pressure Tester E2M Setup
Perform this procedure to prepare the Model E2M Differential Pressure Tester (Figure 6-66)
for use and establish the acceptable cylinder pressure leakage limit.
Procedure
1. Turn the Differential Pressure Tester pressure regulator valve OFF.
2. Position the Master Orifice Valve to the OFF position; handle is horizontal and
directly over the OFF label.
3. Position the Slow Fill Valve (next to the pressure regulator) to the OFF position;
handle is vertical, pointing down.
4. With the Slow Fill Valve in the OFF position, connect the air source to the
Differential Pressure Tester male quick disconnect.

Cylinder
Pressure
Regulator Gauge
Pressure
Gauge

Pressure
Regulator

Cylinder
Adapter AIR Master
Slow Fill
IN Orifice
Valve
Valve

Figure 6-66. Model E2M Differential Pressure Tester

5. Adjust the pressure regulator for indicated 80 psi.
6. Set the Master Orifice Valve to the TEST position; handle is vertical, pointing down.
7. Turn the Slow Fill Valve to the PRESSURIZE position.
8. If necessary, adjust the pressure regulator to maintain an 80 psi indication on the
regulator pressure gauge.
9. Record the cylinder pressure gauge indication on a copy of the Cylinder Inspection
Checklist. This is the Acceptable Cylinder Pressure Leakage Limit.

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Engine Inspection and Service
10. Turn the Slow Fill Valve to the OFF position; handle is vertical, pointing down.
11. Turn the Master Orifice Valve to the OFF position; handle is horizontal, directly
over the OFF label.
12. The Differential Pressure Tester is ready for use; proceed to Section 6-4.11.2.4,
“Cylinder Differential Pressure Test.”
6-4.11.2.2. Differential Pressure Tester Reliability Check
Keep the Differential Pressure Tester clean and check it periodically for accuracy:
1. Apply a line pressure of 100 to 120 psi; close the Slow Fill Valve.
2. Adjust the pressure regulator to 80 psi. The pressure in both gauges should stabilize
with no leakage.
6-4.11.2.3. Leak Check
WARNING
Turn the Ignition Switch OFF and disconnect engine power
before commencing maintenance or inspections. Do not stand
or place equipment within the arc of the propeller.
Exercise care when opening the cylinder pressure valve, air
pressure entering the cylinder may cause the crankshaft to
rotate if the piston is not at bottom dead center.
This simple check will identify conditions undetectable by visual inspection that cannot be
repaired. If the cylinder barrel to head junction is compromised, replace the cylinder;
further inspection is unnecessary if the cylinder fails the leak check.
1. Have an assistant hold the propeller when applying air pressure to the cylinder to
prevent propeller rotation.
2. With the compression tester connected, apply 5 psi oil free air to the cylinder.
3. Position the piston as close to bottom dead center on the compression stroke as
possible, ensuring the intake valve remains closed to allow the cylinder to hold
pressure.
4. Increase the pressure slowly to a maximum value of 80 psi. Saturate the exterior of
the cylinder assembly with a mild non-alkaline soap and water solution.
5. Inspect the cylinder for leakage, indicated by an accumulation of air bubbles.
6. After cylinder inspection, relieve cylinder pressure and remove compression tester.
7. Repeat steps 1 through 5 for all cylinders. Rinse the cylinder thoroughly upon
completion to remove the soap residue.

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6-4.11.2.4. Cylinder Differential Pressure Test
Have an assistant hold the propeller when applying air pressure to the cylinder to prevent
propeller rotation.
WARNING
Turn the Ignition Switch OFF and disconnect engine power
before commencing maintenance or inspections. Do not stand
or place equipment within the arc of the propeller.
Procedure
1. Perform the test as soon as possible after engine shut-down to ensure the piston
rings, cylinder walls, and other engine parts are well lubricated and at operating
clearance.
2. Remove the most accessible spark plug from each cylinder. Identify the cylinder
number and position of the removed spark plugs. Examine the spark plugs to aid in
diagnosing engine and cylinder conditions. Refer to the spark plug manufacturer’s
technical data.
3. Turn the crankshaft by hand in the direction of rotation until the piston in the
cylinder under test is positioned just before its compression stroke.
4. Install the cylinder adapter in the spark plug hole and connect the Differential
Pressure Tester to the cylinder adapter (Figure 6-67).

Figure 6-67. Differential Pressure Test Equipment Usage

NOTE: The Slow Fill Valve should be in the CLOSED position.

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WARNING
Exercise care when opening the cylinder pressure valve. Air
pressure entering the cylinder may cause the crankshaft to
rotate if the piston is not at bottom dead center.
5. Have an assistant secure the propeller to prevent rotation and slowly turn the Slow Fill
Valve in the direction of the PRESSURIZE position to pressurize the cylinder to 20 psi.
NOTE: Some Continental engines feature a lightweight starter which
restricts turning the propeller in the opposite direction of normal rotation.
For these engines, remove the starter prior to commencing the test or
continue to turn the propeller in the normal direction of rotation to seek
the TDC position with the highest pressure indication on the cylinder
pressure gauge.
6. Continue turning the propeller in the normal direction of rotation, against the
pressure until the piston reaches Top Dead Center (TDC) indicated by a sudden
decrease in the force required to turn the crankshaft. If the crankshaft is rotated too
far, back up at least one-half revolution and start over again to eliminate the effect of
valve train backlash and to keep the piston rings seated.
WARNING
The probability of air pressure in the cylinders turning the
propeller during this procedure will be highest when the air
pressure in the cylinder is raised to 80 psi in step 7. Stand
outside the propeller arc with balanced footing while holding
the propeller firmly to avoid injury.
7. With the piston at top dead center, open the Slow Fill Valve completely. Observe the
regulator pressure gauge and adjust the pressure regulator, if necessary, for an 80 psi
indication.
8. To ensure the piston rings are seated and the piston is square in the cylinder bore,
move the propeller slightly back and forth with a rocking motion, while applying the
regulated pressure of 80 psi, to obtain the highest indicated pressure reading on the
cylinder pressure gauge. Adjust the pressure regulator, as necessary, to maintain a
regulated pressure indication of 80 psi.
9. Record cylinder pressure gauge indication. The difference between indicated
cylinder pressure and indicated regulator pressure is the amount of cylinder leakage.
Record cylinder pressure indication as: (pressure reading)/80 psi.
NOTE: Repeat steps 3 through 9 on each engine cylinder. Record
Cylinder Differential Pressure Test results for each cylinder on a copy of
the Cylinder Inspection Checklist.
10. Compare the recorded test results with Table 6-21 to determine what action, if any,
is recommended.
11. Turn the Slow Fill Valve to the OFF position.
12. Disconnect the test equipment from the cylinder and proceed to Section 6-4.11.3,
“Cylinder Borescope Inspection.”

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Table 6-21. Differential Pressure Test Results

Symptoms and
Air Discharge Source Pressure Test Value Observations Recommended Action
Cylinder Differential Normal borescope Continue engine in
Pressure Test reading indications. Oil service. Repeat
above the acceptable consumption stable, no Differential Pressure Test
cylinder pressure leakage excessive oil discharge at next 100-hour/annual
limit. out engine breather inspection.
Cylinder Differential Normal borescope Fly aircraft at Cruise
Pressure Test reading indications. Oil Power setting1 and repeat
below the acceptable consumption stable, no Cylinder Differential
cylinder pressure leakage excessive oil discharge Pressure Test.
limit. out engine breather.
Cylinder Differential Not applicable Remove cylinder for
Pressure Test reading repair.
Air discharge at oil filler/
below the acceptable
crankcase breather.
cylinder pressure leakage
limit after re-test.
Cylinder Differential Oil consumption Remove cylinder for
Pressure Test reading abnormal2, with oil repair.
above or below the discharge out engine
acceptable cylinder breather. Borescope
pressure leakage limit inspection reveals heavy
carbon deposits in
combustion chamber and
on piston crown with
excessive oil puddling in
cylinder barrel.
Cylinder Differential Oil consumption Remove cylinder for
Pressure Test reading abnormal2, with oil repair.
abnormally high discharge out engine
Little to no air discharge at breather. Borescope
oil filler/crankcase inspection reveals heavy
breather. carbon deposits in
combustion chamber and
on piston crown with
excessive oil puddling in
cylinder barrel.

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Table 6-21. Differential Pressure Test Results

Symptoms and
Air Discharge Source Pressure Test Value Observations Recommended Action
Cylinder Differential Normal cylinder Continue engine in
Pressure Test reading borescope inspection service.
above the acceptable results.
cylinder pressure leakage
limit.
Cylinder Differential Normal cylinder Fly aircraft at cruise power
Pressure Test reading borescope inspection setting1 and repeat
Air discharge into
below the acceptable results. Cylinder Differential
induction system
cylinder pressure leakage Pressure test.
limit.
Cylinder Differential Not Applicable Remove cylinder for
Pressure Test reading repair.
below the acceptable
cylinder pressure leakage
limit after re-check.
Cylinder Differential Normal cylinder Continue engine in
Pressure Test reading borescope inspection service.
above the acceptable results.
cylinder pressure leakage
limit.
Cylinder Differential Normal cylinder Fly aircraft at cruise power
Pressure Test reading borescope inspection setting1 and repeat
Air discharge into exhaust
below the acceptable results. Cylinder Differential
system
cylinder pressure leakage Pressure test.
limit.
Cylinder Differential Not Applicable Remove cylinder for
Pressure Test reading repair.
below the acceptable
cylinder pressure leakage
limit after re-check.
Cylinder Differential Dye check of area reveals Remove cylinder for
Air escaping at spark plug
Pressure Test readings cracks. replacement.
spot face
not applicable
Cylinder Differential First cylinder head fin Remove cylinder for
Air discharge at cylinder Pressure Test readings above cylinder barrel wet replacement.
head to barrel juncture or above the acceptable with oil or baked on oil
between barrel fins cylinder pressure leakage residue.
limit.
1. Fly the aircraft at cruise power setting between 65 and 75 percent power according to the Aircraft Flight Manual/Pilots Operating Handbook
(AFM/POH) for a duration that will allow engine oil and temperatures to stabilize, or at least 45 minutes. Repeat the differential pressure
test on the suspect cylinder.
2. A sudden increase in oil consumption from the established, normal trend.

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6-4.11.3. Cylinder Borescope Inspection
Regular engine operation provides an oil coating for the cylinder and minimizes rust
formation. New cylinders are particularly sensitive to rust formation if the engine is
infrequently used or not properly preserved during storage.
NOTE: Ground operation of the engine is an unacceptable substitute for
in-flight engine operation. Ground operation does not provide adequate
cylinder cooling and introduces water and acids into the lubrication
system.
Purpose
The cylinder borescope inspection provides a non-destructive method of visually
examining the internal cylinder components and must be used in conjunction with the
“Differential Pressure Test” to assess the condition of the valve, piston top, deposits, and
the hone pattern on the cylinder barrel and identify abnormal wear patterns which can
contribute to low differential pressure readings or increased oil consumption.
The cylinder wall hone pattern consists of engineered surface “scratches” which aid in
ring seating by allowing the ring and wall surface to wear uniformly and provides a
reservoir of oil for lubrication during ring travel. The cylinder walls and rings are designed
to wear over the life of the engine, particularly in the power stroke area. The visible hone
pattern in the upper portion of the bore may disappear during normal operation; and is not
cause for cylinder replacement.
Required Equipment
• Mechanics tools
• Borescope
Frequency
• During 100-hour/Annual inspection
• If oil consumption is excessive
• After an engine overspeed incident
• Whenever an anomaly is suspected
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
Take preventive measures to avoid burns when performing a
Cylinder Borescope Inspection on a hot engine.

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Procedure
1. Remove the engine cowling as necessary to gain access to the top spark plugs.
2. Remove the top spark plug from each cylinder.
3. Position the piston at bottom dead center on the power stroke. The exhaust valve
will be open with the piston in this position.
4. Insert the borescope probe through the upper spark plug hole and inspect the internal
surfaces of each cylinder, including the exhaust valve and exhaust valve seat.
5. Position the piston at bottom dead center at the end of the intake stroke.
6. Insert the borescope through the upper spark plug hole and inspect the intake valve
and valve seat. Use Table 6-22 and Figure 6-68 through Figure 6-71 to interpret
inspection findings.

Table 6-22. Borescope Inspection Objectives and Corrective Actions

Inspection Item Objective If Abnormality Noted

Inspect:
• Valve seat inserts for erosion, burning
Combustion Chamber • Spark plug heli-coils for protrusion into combus- Remove cylinder for repair
tion chamber
• Heavy carbon deposits/presence of excessive oil
Inspect for signs of leakage or damage indicated
by:
• Localized discoloration on the valve face circum-
Exhaust Valve Face Repair or replace cylinder
ference (Figure 6-69)
• Minute cracks
• Erosion (missing material)
Inspect for signs of leakage or damage indicated
by:
Intake Valve Face • Localized discoloration on the valve face circum- Repair or replace cylinder
ference
• Erosion (missing material)
Inspect exposed surface of bore for:
• Heavy scoring/piston rub (Figure 6-72)
Repair or replace cylinder
• Piston pin rub (wide band pattern in horizontal
plane at 3 o’clock and/or 9 o’clock position)
Cylinder Bore Corrosion (Figure 6-71)1
Excessive oil in cylinder/heavy deposits of carbon Remove cylinder for repair
in combustion chamber
Upper portion of cylinder bore has no visible hone Normal indication for in service
pattern (Figure 6-73) and (Figure 6-74) cylinders
Inspect for:
Piston Head • Piston crown for erosion, missing material Remove cylinder for repair
• Visible damage from foreign debris
1. Remove cylinder for repair or replacement. Perform complete inspection of connecting rod bushing for correct installation and finishing.

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Figure 6-68. Figure 6-69.

Normal Combustion Chamber Burned Exhaust Valve
Exhaust valve has reddish deposit in center with dark Note the edge of valve face has lost all combustion
outer edge. Intake valve has light brown combustion residue with striations moving toward center of valve.
deposits. Combustion chamber has light brown
deposits.

Figure 6-70. Figure 6-71.

Phosphate-Coated Cylinder Phosphate-Coated Cylinder
with Revised Hone Pattern with Corrosion
Phosphate coating provides increased corrosion Phosphate coating in valleys of the cylinder bore hone
protection during initial hours of engine operation. pattern. Light corrosion at top of cylinder bore, above
piston ring travel limit in this area is normal.

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Figure 6-72. Cylinder Barrel Scoring and Piston Rub

Figure 6-73. Typical Wear in Upper Ring Travel

Figure 6-74. Typical Cylinder Wear

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6-4.11.4. Cylinder to Crankcase Mounting Deck Inspection
Purpose
Proper cylinder torque requires a solid mounting surface. Foreign materials, such as
grease or unauthorized sealants applied to the mounting base or flange will not allow
proper fastener preload. Proper torque procedures are critical to engine operation.
Frequency
During 100-hour/Annual inspection
WARNING
Do not apply any form of sealant to the crankcase cylinder
deck, chamfer, cylinder mounting flange, cylinder base O-ring,
or cylinder fastener threads. The use of RTV, silicone, Gasket
Maker or any other sealant on the areas listed above during
engine assembly will cause a loss of cylinder deck stud or
through-bolt torque. Subsequent loss of cylinder attachment
load, loss of main bearing crush and/or fretting of the
crankcase parting surfaces will occur. The result will be
cylinder separation, main bearing movement, oil starvation and
catastrophic engine failure. USE ONLY CLEAN 50 WEIGHT
AVIATION ENGINE OIL ON SURFACES LISTED.
Procedure
Inspect the cylinder-to-crankcase mounting deck for evidence of silicone RTV sealant on
the cylinder deck flange. If silicone RTV sealant or any other unauthorized sealant or
adhesive is discovered, the engine must be completely disassembled, cleaned, inspected
and assembled according to the overhaul instructions in the primary ICA.
1. Remove the engine from the aircraft according to instructions in Section 5-1.
2. Disassemble the engine according to the instructions in the primary ICA (Reference
Section 1-1.1).
3. Clean the engine components according to the instructions in the Chapter 12 of this
manual.
4. Inspect the engine components according to the instructions in the primary ICA
(Reference Section 1-1.1).
5. Reassemble the engine according to instructions in the primary ICA (Reference
Section 1-1.1).
6. Perform the “Post-overhaul Testing” according to instructions in the primary ICA
(Reference Section 1-1.1).
7. Install the overhauled engine according to instruction in Section 5-2.

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6-4.11.5. Baffle Inspection
Purpose
To prevent cylinder deterioration and verify baffles are properly fitted and installed. This
inspection performed in concert with the cylinder inspection.
The heat transfer in piston engines requires efficient and reliable operation of cooling
baffles to prevent rapid deterioration of the cylinders and other engine components. Verify
the baffles are installed, intact, and positioned properly.
Frequency
During 100-hour/Annual inspection or whenever the cowling is removed
Procedure
1. Check the following for deterioration, wear, correct position, and proper contact
with the cowl. Figure 6-75 through Figure 6-78 show improperly positioned baffle
seals.
2. Repair or replace worn or distorted baffles in accordance with the aircraft
manufacturer or Supplemental Type Certificate (STC) holder's information.
3. Check and adjust inter-cylinder baffles to ensure a tight fit.
4. Inspect for holes and cracks that would allow cooling airflow to be wasted. Seal any
cracks or holes by applying a non-corrosive silicone adhesive/sealant. Consult the
aircraft manufacturer for application instructions. Baffle conditions shown in Figure
6-79 shows air gaps that lead to inadequate cooling airflow. Figure 6-80 and Figure
6-81 show evidence of cooling air loss at the baffle seals.
5. Check the integrity of all cooling ducts, heater ducts, etc. and repair as necessary.

Figure 6-75. Improperly Positioned Baffle Seals

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Figure 6-76. Improperly Positioned Baffle Seals

Figure 6-77. Improperly Positioned Aft and Side Peripheral Baffle Seals

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Figure 6-78. Improperly Positioned Aft and Side Peripheral Baffle Seals

Figure 6-79. Aft and Side Baffles with Air Gaps

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Figure 6-80. Cooling Loss Due to Gaps in Baffle Seals

Figure 6-81. Cooling Loss Due to Gaps in Baffle Seals

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6-4.11.6. Cowling Inspection
Purpose
Check cowl openings for restrictions and proper operation of the cowl flap. Cowl flap
operation is an integral function of engine cooling control.
Frequency
During 100-hour/Annual inspection
Procedure
1. Verify add-on accessories and their associated hardware do not restrict cowl inlet,
cowl outlet, and air flow through the cooling fins.
2. Verify the cowl flap rigging and operation meet the appropriate aircraft maintenance
manual specifications.
3. Check for cracks and other obvious physical defects.
6-4.12. Crankcase Inspection
Product improvements over time have reduced material porosity and increased thickness
in certain areas of our crankcases to improve structural integrity.
The part numbers for the engine model crankcases are minimum acceptable candidates for
overhaul. Continental will destroy any preceding crankcase part number when obtained as
a core return.
Table 6-23. Crankcase Casting Numbers
Casting Part Number
Engine Model Casting Number Introduction Year
O-300 530836/530837 1948
IO-360, LTSIO-360, TSIO-360 640432/640433 1973
520 Sandcast 640960/640961 1974
520 Permold 642000/642001 1977
GTSIO-520 642080/642081 1977
Purpose
To verify the crankcase is free of oil leaks, cracks, and physical damage.
Frequency
During 100-hour/Annual inspection
Procedure
WARNING
If neglected, crankcase cracks may progress to the point of
causing major oil leakage or engine structural failure.
CAUTION: Dye penetrant inspection must be performed by a
properly qualified mechanic in accordance with the dye penetrant
manufacturer’s instructions.

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1. Visually inspect the exterior of the crankcase halves for cracks. Carefully inspect the
entire external surface of the crankcase using an inspection light and mirror. If
suspected cracks are discovered, perform a dye penetrant inspection according to the
penetrant manufacturer’s instructions to verify the condition.
NOTE: All crankcase cracks require attention, regardless of size or
location. Do not ignore crankcase cracks.

Cracks are frequently accompanied by oil seepage; investigate all
crankcases for indications of oil leaks.
a. Cylinder deck (white/non-shaded in Figure 6-83 through Figure 6-89 = critical
areas) cracks, regardless of size require immediate crankcase replacement.
b. Repair cracks two inch (5.08 cm) or longer in the shaded (non-critical) locations
of Figure 6-83 through Figure 6-89 according to instructions in Section 10-7.
c. If a crack is found in the non-critical (shaded) area less than two inches (5.08 cm)
in length and there is no oil leakage from the crack, the crankcase may remain in
service, if the following conditions are met:
1) If oil is leaking (visibly dripping) from the crack, repair or replace the
crankcase immediately.
2) Scribe the extremities of cracks smaller than two inches in the non-critical
areas to monitor further growth progression.
3) Inspect cracks previously identified in the non-critical stress areas of Figure
6-83 through Figure 6-89 for progression at 50-hour inspection intervals. If a
crack in the non-critical area progresses to two inches or more in length,
repair or replace the crankcase.
4) Inspect the scribed cracks at the next 50 hour engine inspection for
progression. If no progression is noted, repeat the progression inspection at
each 100-hour inspection interval until the crack is repaired or the crankcase
is replaced.
5) Repair or replace the crankcase if cracks in the non-critical area progress to
two inches or beyond in the shaded locations.
NOTE: Crankcase repairs are not possible with the engine mounted in the
aircraft. To accomplish repair, remove the engine from the aircraft,
disassemble the engine and send the crankcase to a Part 145 Repair
Station certified to perform the crankcase repair.
d. Replace the crankcase immediately, if:
1) Any crack is observed in the critical (white/non-shaded) area.
2) A crack is observed in any of the non-critical (shaded) areas two inches (5.08 cm)
or more in length.
3) Any oil is leaking from the crack in the crankcase.
4) At overhaul, crankcase casting part number is listed in Table 6-23.

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Figure 6-82. Crack in Non-Critical Area of Crankcase, typical

2. Investigate oil leaks as possible crack indications. If oil leaks are the result of
damaged or improperly sealed gaskets, replace questionable gaskets according to the
overhaul instructions.
3. Inspect the crankcase breather for cracks or dents; inspect tube ends for scoring or
eccentricity that may prohibit a proper seal. Discard and replace unserviceable
components.
4. Inspect engine mount brackets for cracks, dents and wear. Inspect hardware for
distorted, stripped threads and damaged wrench flats. Discard and replace
unserviceable components.
5. Inspect the crankcase backbone seam for signs of oil leaks. Oil leakage in this area
may be caused by improperly torqued through bolts. If through bolt torque is less
than the minimum specifications, remove, disassemble, and inspect the engine
immediately to determine the cause of through bolt torque loss.
WARNING
The use of sealants or lubricants other than those specified
herein on mating threads and between mating surfaces may
cause incorrect torque application and subsequent engine
damage or failure.
6. Inspect the cylinder deck for signs of RTV Sealant used on the cylinder deck flange.
If RTV Sealant is found, refer to Section 6-4.11.4, “Cylinder to Crankcase Mounting
Deck Inspection” for corrective action.

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6-4.12.1. Crankcase Critical Stress Areas
Illustrations in Figure 6-83 through Figure 6-89 depict critical stress areas on the
crankcase as white/non-shaded; non-critical stress areas of the crankcases are shaded in
the illustrations.

Figure 6-83. O-200 Engine Crankcase

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Figure 6-84. IO/IOF-240 Engine Crankcase

Figure 6-85. O-300 Engine Crankcase

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Figure 6-86. IO/LTSIO/TSIO-360 Series Engine Crankcase

Figure 6-87. 520/550 Permold Engine Crankcase

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Figure 6-88. 470/520/550 Sandcast Engine Crankcase

Figure 6-89. GTSIO-520 Engine Crankcase

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6-4.13. Engine Mount Inspection
Frequency
During 100-hour/Annual inspection
Procedure
1. Inspect engine mounts for signs of cracks, deterioration, proper assembly and
security. If cracks are suspected, perform a nondestructive inspection using
fluorescent penetrant or eddy current methods to determine engine mount condition.
2. Inspect engine mount isolators for signs of deterioration, proper assembly and
security. Replace engine mount isolators exhibiting any of these conditions.
WARNING
Do not allow a cracked engine mount to remain in service.
Replace upon discovery.
3. Replace damaged or deteriorated engine mounts or engine mount isolators.
6-4.14. Induction System Inspection
Purpose
Check the integrity of the air filter, seals, and airbox to prevent particulates from entering
the engine that can abrade cylinder walls and ring faces thereby damaging the engine.
Frequency
During 100-hour/Annual inspection
Procedure
1. Remove and inspect the induction air filter for cleanliness, normal operation and the
absence of gaps or leaks in the filtering element. Verify the air filter seal prevents
airflow except through the filter. Inspect or replace, as required, according to the
aircraft manufacturer/STC holder's instructions.
2. Verify the integrity of the airbox; look for alternate air circuits which can bypass the
filtering system. Any holes or bypass circuits found behind the filtering element
should be repaired, as required, according to the aircraft manufacturer/STC holder's
instructions.
3. Verify operation of the alternate air door and the integrity of the seal in the closed
position. Verify the door operating mechanism closes securely. Replace or repair, as
required, according to the aircraft manufacturer/STC holder's instructions.
4. If oil analyses are done on engine oil samples, check the silicone content of the most
recent oil analysis and the overall silicone trend to further assess the possibility of
Induction System leaks or pilot operational issues such as extensive use of
carburetor heat or alternate air during ground operation.
5. Inspect the induction tube and hose connections to verify proper installation.
Induction tubes incorporate a “bead” (Figure 6-90) which provides an anchor point for
the induction tube clamps and enhances the seal between the induction tube and hose.
Remove, inspect and install induction system according to instructions in the
applicable Maintenance and Overhaul (or Overhaul) Manual if induction tubes, hoses
or clamps are improperly installed or inspection identifies parts as unserviceable.

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a. Visually inspect the induction system clamps for proper fit and positioning.
Clamps should be positioned squarely over the joint between the induction tubes
and hose (Figure 6-91), inboard of the induction tube bead; no part of the end of
the induction tube should be visible with the hose and clamp properly installed.
Loosen the clamps, reposition, and torque the clamps 25-35 in. lbs. If the clamp
will not tighten or remain torqued, the clamp is unserviceable - replace the
clamp.
b. Perform a visual inspection on the induction hoses for proper fit and positioning.
Hoses should be flexible; splits, tears, or cracks are unserviceable conditions.
Replace cracked, split, or torn induction hoses. Hoses should not exhibit “twists”
from misalignment, which can cause stress cracks. Hoses must be positioned
over the induction tubes to secure the induction tube beads within the clamped
portion of the hose.
c. Perform a visual inspection on the induction tubes. Replace tubes exhibiting deep
scratches, dents, cracks, or eroded sealing beads.

Figure 6-90. Induction Tube Bead Location

Figure 6-91. Properly Installed Induction Tube, Hose and Clamps

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6-4.15. Ignition System Inspection
Purpose
Verify the following:
• Magneto housing and flange is free of damage
• Magneto to engine timing is set properly
• Ignition leads are intact and secure
• Spark plugs are clean, operating properly, and correctly gapped
Frequency
During 100-hour/Annual inspection
Procedure
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent an accidental engine start. Do not stand or
place equipment within the arc of the propeller.
1. Ignition Switch................................................. OFF
2. Remove the spark plug leads from the top and bottom spark plugs and ground the
leads to the engine.
3. Verify the magnetos are properly grounded.
4. Clean the ignition leads and visually inspect the ignition leads for chafing,
deterioration and insulation breakdown. Replace worn, frayed or chafed ignition
wires.
5. For engines equipped with impulse coupled magnetos, perform an “Impulse
Coupling Functional Check” according to the instructions in Section 6-4.15.1.
6. Remove the spark plugs from each cylinder. Clean, inspect, and rotate spark plugs
according to instructions in Section 6-4.9.2.
WARNING
Failure to maintain the magneto, spark plugs and ignition leads
can cause engine damage or failure due to misfire.
7. Perform the “Crankshaft Top Dead Center Alignment” in Section 6-4.9.1.1 to
position the crankshaft to the proper position from magneto to engine timing.
8. Visually inspect the external surfaces of the magneto for physical security or
corrosion. Replace non-Continental magnetos exhibiting damage, unusual wear or
corrosion. Correct Continental magneto discrepancies according to the Magneto
Service Manual.
9. For pressurized magnetos:
NOTE: Pressurized magnetos are equipped with a desiccant filter; the
filter media is normally white in color and darkens when contaminated.

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a. Inspect the magneto filter body, pressurization fittings, and hoses for physical
condition and security. Replace missing, cracked or damaged magneto
pressurization parts.
b. Inspect the filter media for contamination; the media within the translucent filter
body should be uniform in color and shape. If the media appears to be
contaminated, discard and replace the filter with a new one (Section 10, “Non-
Overhaul Repair and Replacement”.
c. Verify the filter is installed with the drain positioned farthest from the magneto; if
properly installed, the arrow on the filter body will point toward the magneto and
the drain will be physically lower than the inlet and outlet fittings for proper
drainage. Adjust filter installation to ensure the drain is lower than the fittings.
CAUTION: Verify the magneto pressurization vent is open. If the
vent is clogged, nitric acid formation in the magneto will cause rapid
degradation of the magneto internal components, leading to
imminent magneto failure.
d. Verify the reducer is fully seated in the bottom of the filter drain tube and the
orifice is clear of debris to allow for drainage. If liquid is accumulated in the
bottom of the filter, the drain or magneto vent may be clogged:
1) Replace the desiccant filter.
2) Remove, disassemble and inspect Continental magnetos for corrosion
according to the instructions in the Magneto Service Manual. Remove and
replace Champion (Slick) Magnetos with new or serviceable units.
10. Perform a 100-Hour inspection on Continental magnetos according to instructions in
the Magneto Service Manual.
11. Note the magneto RPM drop test results recorded during the “Engine Operational
Check” in Section 6-4.7. If magneto RPM drop or spread during run-up was not
within published limits, inspect, troubleshoot, repair and adjust as required to
correct discrepancy.
12. Check magneto to engine timing according to the “Magneto to Engine Timing”
instructions in Section 6-4.9.1.2. If magneto timing cannot be adjusted:
a. Remove the magneto from the engine according to the instructions in Section 10-
5, “Magneto Replacement.”
b. Perform a “Magneto Drive Coupling Inspection” according to the instructions in
Section 6-4.15.3.
c. Replace Champion (Slick) magnetos with a new, rebuilt, or serviceable magneto.
Troubleshoot and repair Continental magnetos according to instructions in the
Magneto Service Manual.
13. For engines equipped with a shower of sparks ignition system, perform a “Starting
Vibrator Functional Check” according to the instructions in Section 6-4.15.2 after
verification of magneto to engine timing.

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6-4.15.1. Impulse Coupling Functional Check
This functional check is a simple method to determine if the magneto impulse couplings
are functioning properly without disassembly. This functional check is not a suitable
substitute for the impulse coupling inspection in the Magneto Service Manual.
WARNING
Do not stand or place equipment within the arc of the propeller.
Procedure
1. Disconnect the ignition harness from all spark plugs and ground the ignition harness
leads to the engine.
2. Remove top spark plugs from the engine
3. Mixture Control ............................................... IDLE CUT-OFF
4. Throttle............................................................. CLOSED
5. Fuel Selector Valve .......................................... OFF
6. Master Power Switch ....................................... ON
7. Crank the engine several revolutions using the Start switch (if separate from the
Ignition switch) or Ignition switch (if start function is controlled by the Ignition
switch).
RESULT: Impulse coupling operation is audible and can be felt through the magneto
housing. The “clicking” sound from the impulse couplings should be consistent
while the engine is cranked. If no “clicking” is heard, or the clicking is intermittent,
remove the magnetos and service according to the manufacturer's instructions.
8. Disconnect the aircraft battery according to the aircraft manufacturer's instructions.
9. For shower of sparks ignition only: Turn and hold the Ignition Switch in the START
position and verify continuity between the right magneto P-lead and ground. If
continuity is not present, repair the circuit before proceeding.
10. Ignition Switch................................................. OFF
11. Disconnect the P-lead from each magneto. Verify continuity between both magneto
P-leads and ground with a multimeter. If either circuit is faulty, repair the circuit
before proceeding.
12. Reconnect the magneto P-leads and place the Ignition Switch in the OFF position.
13. If ignition system maintenance is complete, install top spark plugs (with new
gaskets) according to instructions in Section 6-4.9.2 and reconnect the ignition
harness according to the instructions in Section 6-4.9.3.

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6-4.15.2. Starting Vibrator Functional Check
WARNING
Do not stand or place equipment within the arc of the
propeller.
1. Disconnect aircraft electrical power from the starter according to the aircraft
manufacturer's instructions.
2. Perform the “Crankshaft Top Dead Center Alignment” instructions in Section 6-
4.9.1.1 to position the No. 1 cylinder at the proper ignition timing position.
3. Remove the lower spark plug lead from the No. 1 cylinder. Position the tip of the
spark plug lead 3/16” from engine ground.
4. Master Switch .................................................. ON
CAUTION: The starting vibrator duty cycle is 16.6% or 20/120
seconds; do not engage the starting vibrator for longer than 20
seconds in a two minute period. Exceeding the duty cycle will
overheat the circuit and may damage the starting vibrator.
5. Ignition Switch.................................................START (maximum 20 seconds)
RESULT: A strong blue spark emits from the spark plug lead at a few degrees before
top dead center on the No. 1 cylinder compression stroke. If no spark is observed
before the maximum advanced position, inspect the left magneto main and retard
contact point timing circuit according to the appropriate manufacturer's Magneto
Service Manual.
6. Reconnect the spark plug lead to the No. 1 cylinder lower spark plug.
7. Reconnect aircraft electrical power to the starter according to the aircraft
manufacturer's instructions.
6-4.15.3. Magneto Drive Coupling Inspection
1. Remove the magnetos from the engine according to the “Magneto Replacement”
instructions in Section 10-5.
2. Inspect the drive coupling bushings and retainers for serviceability and proper
installation. If the bushings are torn or exhibit missing material, perform a “Foreign
Object Contamination Inspection” according to instructions in Section 6-5.7.
3. Perform a “Gear Tooth Inspection” according to instructions in Section 11-1.1 on
the magneto drive gear and idler gear assembly. Rotate the crankshaft 360° in order
to inspect the circumference of the gear. If the gear teeth are chipped, broken, or
otherwise damaged, remove, inspect and make repairs, if necessary, to the magneto
drive gear or accessory drive adapter according to instructions in the primary ICA
(Ref: Section 1-1.1). Perform a “Foreign Object Contamination Inspection”
according to instructions in Section 6-5.7.

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6-4.16. Engine Gauge Inspection
CAUTION: Inaccurate aircraft engine related gauges can cause
operation outside of engine certification and specification limits.
Aircraft gauge calibration errors can be particularly harmful for
high horsepower engines. Gauges may require re-marking for
modified (STC) engines. Significant aircraft engine gauge
inaccuracies can lead to engine damage.
Purpose
Verify proper gauge operation and ensure reliable condition feedback to the pilot.
Frequency
During 100-hour/Annual inspection
Procedure
Verify the following indicators are working properly according to instructions in the
Aircraft Maintenance Manual. Repair or replace faulty components.
• Tachometer
• Manifold pressure gauge
• Fuel flow gauge
• Oil pressure gauge
• Oil temperature gauge
• Cylinder head temperature gauge
• Exhaust gas temperature gauge
• Turbine inlet temperature gauge (if equipped)
NOTE: Verify the accuracy of the EGT/TIT indicating system. The
aircraft manufacturer may require EGT/TIT reporting be operational for
all categories of flight. Consult the Aircraft Maintenance Manual for
interval and operational requirements. In many cases, EGT/TIT
calibration is a 100-hour inspection requirement.

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6-4.17. Fuel System Inspection
Engine operation and cooling are directly related to the correct fuel-air ratio. Improper
fuel settings can affect engine performance in terms of both power and throttle response.
For FADEC engines, refer to the “Fuel System Inspection” in the primary ICA.
Purpose
• Verify fuel injector operation
• Verify fuel lines are clear
• Verify the fuel pump is properly adjusted
Frequency
• During 100-hour/Annual inspection
• Clean fuel injectors at the first 100-hour inspection and every 300 hours (or annually)
thereafter, whichever comes first.
Procedure
1. Inspect each fuel line to the connection point at the fuel manifold valve for chafing,
wear, or damage. Replace worn, chafed or damaged fuel lines with new fuel lines.
2. Inspect the fuel manifold valve for leaks and security of fittings.
3. Clean the fuel injectors:
a. Remove the fuel injectors (Section 10-2.2 or Section 10-2.4) from the cylinders.
Remove the O-rings from the fuel injectors, if present.
b. Clean the fuel injectors in an ultrasonic cleaner. If an ultrasonic cleaner is not
available, soak the fuel injectors in lacquer thinner. After successful cleaning, use
dry, oil-free compressed air (from inlet to outlet) to remove residual cleaner from
the nozzles.
c. Install the fuel injectors (Section 10-2.3 or Section 10-2.5).
4. Inspect the fuel line and fittings from the fuel pump outlet to the fuel manifold
valve, including the fuel filter (if installed) for wear or damage. Replace faulty parts.
5. Turn the aircraft boost pump (if equipped) to the ON position.
a. Visually inspect the fuel pump, fuel lines, fuel manifold valve, fuel hoses and
fittings for signs of fuel leaks.
b. Verify no fuel is leaking from the fuel pump dry bay drain.
c. Inspect each fuel injector to the fuel line connection point.
6. Turn the aircraft boost pump OFF.
7. Perform the “Fuel System Operational Check” according to instructions in
Section 6-4.7.4.
NOTE: The “Fuel System Operational Check” is part of the “Engine
Operational Check” performed at the beginning and conclusion of the
100-hour scheduled inspections.

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6-4.18. Throttle and Mixture Control Lever Inspection
Reference (latest version): CSB08-3
NOTE: Continental replaced bronze throttle and mixture control levers in
all applications where the lever mated with a splined shaft with improved
stainless steel control levers featuring machined splines in the chamfer
where the control lever contacts the throttle or mixture control shaft
splines. 

This inspection does not apply to throttle and control assembly levers
installed with a pin through the lever and shaft rather than a lock nut on a
threaded shaft.
WARNING
R e p l a c e c o n t r o l l e v e r s or s h a f t s e x h i b i t i n g d a m a g e ,
deformation, or material loss. Improper or negligent control
lever installation may result in loss of engine control.

Replace all bronze control levers on threaded shafts with the
designated stainless steel equivalent during the next 100 hour
or annual inspection or the next maintenance interval requiring
removal of the lock nut on the lever to be removed, whichever
comes first.
1. Inspect the serrated, chamfered edges of the control lever and shaft (Figure 6-92).
Verify the serrations are well defined and mechanically interlock when assembled. If
the splines are malformed or worn, slippage is possible; replace the control lever.

Figure 6-92. Serviceable Throttle/Mixture Control Lever & Shaft Splines

2. At installation, lubricate the shaft threads with clean 50-weight aviation engine oil,
align the control lever to the desired angle, engage the splines in shaft with the
splines in the lever, install a new lock nut and tighten the lock nut to secure the lever.

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Figure 6-93. Worn Throttle and Mixture Control Lever & Shaft Splines
3. Rotate the lever away from the stop pin and apply 100-120 in. lbs. torque to the nut.
Check the control lever after torque application to ensure there is no free play or
movement of the control lever on the component shaft.
a. If free play or movement is felt after the nut is torqued, remove the control lever
and determine the cause for movement (if applicable, reinstall the control lever
and repeat the installation process.
b. If lever continues to exhibit free play after being torqued, replace the control
lever. If the source of the free play is determined to be the fuel pump or throttle
shaft, replace the next higher assembly (fuel pump or throttle assembly).

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6-4.19. Engine Control Linkage Inspection
Purpose
To ensure proper operation and avoid accelerated wear, inspect the engine control linkage
for excessive play, which may restrict control travel or damage control levers or cables.
Frequency
• During 100-hour/Annual inspection
Procedure
1. Inspect the pivot points of levers and linkages for debris, old grease, and oil.
WARNING
If the lock nut securing a bronze throttle or mixture control
lever is loosened for any reason, replace the bronze lever with
the appropriate stainless steel replacement lever.
2. Inspect throttle and mixture control lever condition and security according to the
“Throttle and Mixture Control Lever Inspection” instructions in Section 6-4.18.
Grasp the lever firmly and apply lateral force to the end of the lever. No free play is
permitted between the shaft and control lever.
3. Replace worn or corroded linkage and attaching hardware according to the aircraft
manufacturer's instructions.
CAUTION: When utilizing compressed air, wear OSHA approved
protective eye wear. Never exceed 30 psi when using compressed
gases for cleaning purposes. (OSHA 1910.242(b))
4. Clean pivot point areas thoroughly with Stoddard solvent. After cleaning, dry each
area using compressed air.
5. Unless otherwise specified by the aircraft manufacturer's instructions, apply LPS 2,
Loctite MaintainTM Lubricant, or equivalent, to each pivot point (Figure 6-94 or
Figure 6-95), including the throttle shaft bushings.
6. Consult the aircraft manufacturer’s instructions concerning aircraft engine control
cable attach point inspection, cleaning, repair, installation, and lubrication.
7. Cycle throttle and mixture controls through the full range of motion.
a. Verify each control has full range of travel and the required safeties are in place.
b. Ensure levers and linkages do not bind and control movement is unrestricted by
parts or components in close proximity.

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Figure 6-94. Throttle and Control Assembly Lubrication Points

Figure 6-95. Throttle and Metering Assembly Lubrication Points

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6-4.20. Induction System Drain Inspection
NOTE: This inspection only applies to fuel injected engines. Engines
with carburetors do not offer induction system drains.
Induction system drains are incorporated on all engines featuring cross-flow (induction
tubes above) cylinders. Engine models with updraft induction (below the cylinder)
incorporate drains in the induction tubes to allow excess fuel to drain from the induction
system. A check valve is incorporated in the induction drain to isolate the fuel in the
induction system when the intake valve opens. Naturally aspirated engines use a two-way
check valve. Because the induction system on turbocharged engines can operate in a
negative pressure state, a three-way check valve is required for the turbocharged
induction. An improved drain connector (Figure 6-96) was introduced in 2000 for
improved cold weather starting characteristics. If the cylinder drain terminates at the taper
(Part No. 632068), the drain connector is no longer available, replace with Part No.
655742, or later, if unserviceable, or to improve cold weather operation.
Purpose
Induction system drains evacuate excess fuel from the intake ports. Restricted induction
system drains can accumulate excessive amounts of fuel and may cause hydraulic lock.
Frequency
During all periodic inspections

Figure 6-96. Induction Port Drain Connectors

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6-4.20.1. Induction System Drain Inspection (Naturally Aspirated Engines)
1. Remove the aircraft cowling according to the aircraft manufacturer’s instructions.
2. At each 100-Hour/Annual Inspection, remove the connectors (Figure 6-96) from the
cylinder head and clean according to the instructions in Section 10-3.1 and install
serviceable, or new connector fittings in each cylinder according to the instructions
in Section 10-3.2.
3. Connect a section of clear, fuel rated hose to the aircraft fuel drain outlet.
WARNING
Vacuum pumps are commercially available from a number of
sources. Use only a spark-arrested vacuum pump, designed for
use with flammable liquids.
4. Apply light vacuum (< -5 psi) from a spark-arrested source rated for flammable
liquids to the clear hose connected to the aircraft fuel drain outlet and activate the
aircraft engine fuel priming system for five seconds.
RESULT: Fuel drains from the hose into the container.
5. Apply light positive pressure (< 5 psi) from a spark-arrested source rated for
flammable liquids to the clear hose connected to the aircraft fuel drain outlet and
activate the aircraft engine fuel priming system for five seconds.
RESULT: Drain valve is closed - no fuel flows into the clear hose.
6. Remove air pressure source from the fuel drain hose. Allow the fuel in the hose to
drain into a fuel rated container.
RESULT: Fuel drains from the hose into the container.

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6-4.20.2. Induction System Drain Inspection (Turbocharged Engines)
1. Remove the aircraft cowling according to the aircraft manufacturer’s instructions.
2. At each 100-Hour/Annual Inspection, remove the connectors (Figure 6-96) from the
cylinder head and clean according to the instructions in Section 10-3.1 and install
serviceable, or new connector fittings in each cylinder according to the instructions
in Section 10-3.2.
3. Connect a section of clear, fuel rated hose to the cylinder drain hose.
WARNING
Vacuum pumps are commercially available from a number of
sources. Use only a spark-arrested vacuum pump, designed for
use with flammable liquids.
4. Apply light vacuum (< -5 psi) from a spark-arrested source rated for flammable
liquids to the clear hose and activate the aircraft engine fuel primer system for five
seconds. 
RESULT: No fuel flows into the clear hose.
5. Remove the vacuum source from the drain and allow the residual fuel to drain in to a
fuel rated container.
RESULT: Fuel drains from the hose into the container.
6. Apply light pressure (< 5 psi) from a spark-arrested source rated for flammable
liquids to the clear hose and activate the aircraft engine fuel primer system for five
seconds. 
RESULT: No fuel flows into the clear hose.
7. Remove air pressure source from the cylinder drain hose. Allow the fuel in the hose
to drain into a fuel rated container.
RESULT: Fuel drains from the hose into the container.

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6-4.21. Turbocharger and Exhaust System Inspection
Purpose
Verify the integrity of the turbocharger and exhaust system, including the heater muff (if
installed). Isolate and correct cracks or leaks in the exhaust system.
Frequency
During 100-hour/Annual inspection
CAUTION: Ensure the turbocharger and exhaust system
components are cool before inspection to prevent burns.
Procedure
1. Remove airframe items that hinder visual inspection of the exhaust and turbochargers.
2. Clean the exhaust system, removing oil and grease, by spraying the exhaust systems
parts with Stoddard solvent. Allow the solvent to drain and wipe the parts with a
clean cloth.
CAUTION: Cracks in the exhaust system can release carbon
monoxide in the nacelle or the cabin; correct exhaust leaks before
further flight.
3. Inspect the exhaust system components according to the instructions in Table 6-24.
Table 6-24. Exhaust Inspection Criteria
Part Inspection Action
Check parts for the following:
• Burned areas
Stacks
• Cracks
Risers
• Loose parts/hardware
Elbows
• Pay particular attention to welded areas and seams, checking for cracks.
• Replace parts that are cracked, burned, or worn
Slip joints Check for bulges, cracks, or hot spots (see Figure 6-97)
Inspect spot-weld (or rivet) areas for cracks or physical damage.
Inspect the corner radii of clamp inner segments for cracks with a flashlight and mirror.
Inspect the inner segment spacing.
Multi-segment V-band Inspect the clamp outer band for flatness using a straight edge, especially within 2
clamps inches of spot-weld tabs that retain the T-bolt fastener - clearance must be less than
0.062 inches.
Verify 100% inner and outer band segment contact.
To replace a multi-segment V-band clamp, refer to the primary ICA. Ref: Section 1-1.1
Inspect the heat exchanger seams, joints and transitions with a flashlight and mirror or a
Heater muff flexible borescope for physical damage, cracks, corrosion, and burn-through. Inspect
connecting flanges for security and proper mating.

4. Connect a high volume, dust-free, air pressure source to the exhaust tailpipe outlet.
5. Apply five (5) psi of air pressure to the exhaust system.
6. Apply soapy water to the exhaust system and check for bubbling in areas of the
exhaust other than the slip joints. If bubbling is found, replace the leaking exhaust
components according to the instructions in primary ICA (Reference Section 1-1.1)
or aircraft maintenance manual.

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SLIP JOINTS

INSPECT FOR
CRACKS,
BULGES, OR
HOT SPOTS

Figure 6-97. Exhaust Slip joint Inspection

WARNING
Exhaust system weld repairs may only be performed by an
FAA Part 145 authorized repair station certified to perform the
specific repairs.

Figure 6-98. V-band Clamp Inspection

7. Visually inspect the exhaust stacks and transition unit for wear, leaks, cracks, or
distortion. Replace worn, leaking, cracked, or distorted exhaust parts. Inspect the
exhaust manifold connections at the cylinder to verify the physical security of the
exhaust flange, gasket and exhaust manifold fasteners. Exhaust system removal and
installation procedures may be found in the primary ICA (Ref: Section 1-1.1) or the
aircraft maintenance manual, if disassembly is required. (Reference Section 1-1.1)
8. Remove the multi-segment V-band clamps from the exhaust tailpipes according to
instructions in the primary ICA (Ref: Section 1-1.1) or the aircraft maintenance
manual. Clean the outer band of the multi-segment V-band clamps with crocus cloth.
Inspect the V-band clamps according to the instructions in Table 6-24.

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9. Inspect the turbocharger oil reservoirs, oil inlet and outlet fittings and surrounding
area for signs of leakage. Torque fasteners or fittings to Appendix B specifications
or replace leaking parts, as required to remedy leaking reservoirs or fittings.
10. Remove the induction air supply from the turbocharger compressor according to the
aircraft manufacturer’s instructions. Inspect the induction air supply duct for wear,
deformation, cracks or other physical damage; replace, if necessary.
11. Remove the turbocharger compressor discharge duct from the induction system
according to instructions in the primary ICA (Ref: Section 1-1.1) or the aircraft
maintenance manual. Inspect the hardware for wear, deformation, cracks or other
physical damage; replace, if necessary.
12. Inspect the turbine and compressor housings for cracks or physical damage,
especially at the mounting flanges. If cracks or physical damage is discovered,
replace the turbocharger with a new, rebuilt or serviceable unit.
13. Inspect the turbine and compressor wheel blades for damage. If turbine or
compressor blades are damaged, replace the turbocharger with a new, rebuilt or
serviceable unit.
14. Spin the turbine shaft to check for freedom of movement and end play. If the turbine
or compressor blades touch the housing during rotation, if the shaft does not rotate
freely, or if the shaft exhibits noticeable “wobble” during rotation, replace the
turbocharger with a new, rebuilt or serviceable unit.
15. Inspect the interior of the turbine and compressor housings for oil, indicating oil seal
damage or a faulty check valve. If oil is found inside the housing, troubleshoot to
isolate cause of oil accumulation.
16. Inspect the wastegate for cracks or physical damage. If the wastegate is cracked or
damaged, replace the wastegate with a new, rebuilt or serviceable unit. Inspect the
security of the mounting flange fasteners, retorque if fasteners appear loose.
17. Inspect the wastegate actuator fittings for leaks and physical security; retorque loose
fittings to Appendix B specifications. If leaks persist, replace O-rings, retorque
fittings and repeat leak inspection after a ground engine run. Inspect the wastegate
actuator hydraulic hoses for chafing, nicks, cuts or leaks; replace hoses exhibiting
these conditions.
18. Inspect the wastegate actuator and butterfly valve for general condition and freedom
of movement. Check the link rod pins and levers for wear. If the wastegate actuator,
butterfly valve, link rod pins or levers are worn, binding, or damaged, replace the
wastegate actuator.
19. Clean and lubricate the butterfly valve and associated linkages:
a. Inspect fixed wastegate valves according to the instructions in the primary ICA
(reference Section 1-1.1).
b. For variable wastegate valves resembling the Figure 6-99, lubricate the butterfly
shaft with Mouse Milk® (see Table 3-6) penetrating lubricant at initial
installation and at each 100-hour maintenance interval.

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NOTE: The installed wastegate may be positioned in a manner that differs
from the illustration. The fittings used to connect the hydraulic hoses may
differ from those depicted in the illustration.

Figure 6-99. Wastegate Lubrication Points, typical

20. For applicable engine models: remove, disassemble, and inspect the turbocharger oil
supply check valve according to the instructions in Section 6-4.21.1.
21. Inspect the wastegate controller and fittings for physical condition and security. If
the wastegate controller exhibits physical damage, replace the wastegate controller
with a new, rebuilt, or serviceable unit. Inspect the wastegate controller hoses, or
tubes, for chafing, nicks, cuts or leaks; replace hoses exhibiting these conditions.
Inspect the wastegate controller reference hoses or tubes for bends, dents, nicks or
leaks; replace reference lines exhibiting these conditions.

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22. Inspect the wastegate controller (Figure 6-57) housing for oil leaks around the
diaphragm, deck pressure sensing port, oil inlet, oil outlet, or adjustment screw. If
oil is leaking from a fitting, remove the fitting and replace O-rings, install and torque
the fitting to Appendix B specifications. If oil is leaking from the housing, replace
the wastegate controller with a new, rebuilt, or serviceable unit.

Figure 6-57 Sloped Controller, (repeated for reference) typical

23. Inspect the overboost valve housing for cracks or physical damage; replace cracked or
damaged overboost valve assembly with a new, rebuilt or serviceable unit. Remove
accumulated debris from the overboost valve exposed bellows assembly shaft (behind
the housing flange) and housing according to instructions in the primary ICA (Ref:
Section 1-1.1). Inspect the mounting flange for fastener security; replace missing
fasteners; re-torque loose overboost valve fasteners to Appendix B specifications.
24. Inspect the compressor housing V-band clamp, exhaust housing bolts and lock tabs
for security. Torque loose hardware to Appendix B specifications.
25. Reassemble the turbocharger and exhaust system.
a. Install the induction system air supply according to aircraft manufacturer’s
instructions.
b. Install the turbocharger compressor discharge duct and exhaust pipe/heater muff
according to the instructions in the primary ICA (reference Section 1-1.1) or the
aircraft maintenance manual.

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6-4.21.1. Turbocharger Oil Supply Check Valve Inspection
NOTE: Check valve filter assembly (Part No. 658746) is integrated in the
TSIO-550-K and TSIO-550-N engine designs to protect the check valve
from contaminants. The filter assembly is optional for retrofit on other
engine models.
Applicable Engines: TSIO-520-BE, LB, UB, WB; 
TSIO-550-A, B, C, E, G, K, N;
TSIOF-550-D, J, K, P;
TSIOL-550-B, C
The check valve is designed to prevent oil flow from the engine oil cooler to the
turbocharger when the engine is shut down. If the check valve does not close properly, or
becomes blocked with foreign matter, the check valve may remain open, allowing oil to
continuously flow to the turbocharger (usually accompanied by oil puddling below the
turbocharger).
Purpose
Inspect, clean and lubricate the check valve filter assembly (if equipped) or the check
valve.
Procedure
1. For engines without a check valve filter assembly, proceed to step 2. For engines
with a check valve filter assembly:
a. Visually inspect the oil supply circuit and the turbocharger oil reservoirs for
evidence of oil leaks. If no leakage is evident, check valve disassembly and
inspection is not required.
b. Disconnect the oil supply hose from the oil cooler at the inlet of the filter
assembly. Install a protective plug in the oil hose.
c. Disconnect the check valve filter assembly from the check valve. Install a
protective cap on the check valve fitting.
d. Use a parts washing station with a flexible fluid nozzle, serviced with clean
mineral spirits, to flush the check valve filter assembly screen in the reverse
direction of normal flow. Hold the filter up to a light source to inspect the filter
screen.
1) The check valve filter assembly screen should be intact, with equal mesh
spacing across the screen material. If the check valve filter assembly screen is
missing or damaged, replace the check valve filter assembly. If debris
remains in the screen, repeat the cleaning and inspection process up to two
additional times. If cleaning is unsuccessful, replace the check valve filter
assembly.
2) If the check valve filter assembly screen is clean, proceed to step 10.
2. For engines without a check valve filter assembly, disconnect oil hose from the oil
cooler at the check valve.

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3. Disconnect check valve (where applicable) from:
a. hose servicing turbocharger (see Figure 6-101), or
b. tee fitting (Figure 6-102).

Figure 6-100. Check Valve, Detail

Figure 6-101. Single Turbocharger Lubrication (check valve location), typical

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Figure 6-102. Dual Turbocharger (check valve location), typical

4. To disassemble the check valve (see Figure 6-100), unscrew the check valve cap
from the check valve body. Remove the sealing ball, spring cage, and spring.
CAUTION: Do not use metal cleaning tools such as brass or wire
brushes or steel wool to clean the check valve.
5. In a clean container, clean check valve and all components with mineral spirits.
6. Completely dry the body of the check valve with compressed air.
7. Inspect the check valve and all components for debris, corrosion, or physical
damage. If damage is found, replace the entire check valve according to the
Maintenance and Overhaul Manual instructions. If no damage is found, proceed to
next step.
8. Apply a light coating of 50-weight aviation oil to all components and threads of
check valve body and cap.
CAUTION: Do not force or cross-thread the check valve cap into the
check valve body. Misaligning the internal components could cause
the check valve to malfunction and hinder turbocharger lubrication.

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9. Assemble the check valve (see Figure 6-100, for correct orientation):
a. Stack the spring, spring cage, and sealing ball and properly seat these internal
components in the check valve body.
b. Insert the check valve cap squarely over the check valve body and tighten until
the sealing surfaces make finger tight contact.

Figure 6-100, “Check Valve, Detail,” (repeated for reference)

CAUTION: Do not use sharp metal tools to verify movement of
internal components, as it may damage the check valve’s operation.
c. Carefully insert a clean 3/16” nylon (or equivalent) drift tool into the check valve
(as shown in Figure 6-103). Use light pressure to verify free, unobstructed
movement of the internal components. Normal travel is approximately 0.06 inch.

Figure 6-103. Check Valve Functional Check

d. Torque the check valve cap and body to 100-150 in.-lbs. and repeat step 9, c.

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CAUTION: Check valve and the check valve filter assembly must be
installed with the arrow pointing in the direction of oil flow (from the
oil cooler to the turbocharger) (see Figure 6-101 or Figure 6-102). If
the check valve or the check valve filter assembly is installed
improperly it will cause the check valve to malfunction and prevent
turbocharger lubrication.
10. Connect check valve (with the check valve arrow pointing towards the turbocharger)
to the turbocharger oil supply hose (Figure 6-101) or the tee fitting (reference Figure
6-102) and torque to 150-195 in.-lbs.
11. If equipped, connect the check valve filter assembly (with the arrow pointing
towards the check valve) to the turbocharger check valve and tighten finger tight.
Secure the check valve with a back up wrench and torque the check valve filter
assembly to 150-195 in.-lbs.
12. Connect the oil hose from the oil cooler to the open end of the check valve filter
assembly (if equipped) or check valve and tighten nut finger tight. Torque hose
fittings to 150-195 in.-lbs.
13. Replenish engine oil levels according to the instructions in Section 6-4.8.
14. Perform a “Ground Run-up”; check for oil leaks and correct any discrepancies.
6-4.22. Alternator Inspection
Frequency
During 500-hour inspection
Procedure
1. Remove engine cowling and aircraft components necessary to gain access to the
alternator.
2. Remove the alternator according to instructions in Section 10-4.1.1 or Section 10-
4.1.1. Perform the “Alternator Drive Coupling Inspection” in Section 6-4.22.1 or
Section 6-4.22.2 on all gear driven alternators. For belt driven alternator removal,
refer to the engine primary ICA (Ref: Section 1-1.1).
3. Inspect Continental alternators according to the Alternator Service Manual (“Related
Publications” in Section 1-2.5); correct any discrepancies discovered during the
inspection. For engines equipped with Hartzell (Kelly) ES10024 consult Hartzell
Service Information Letter A-135 for one time inspection requirements. For engines
equipped with Hartzell (Kelly) ES-6012 or ES7024 belt driven alternators, consult
Hartzell Service Information Letters A-137 and A-138 for one time inspection
requirements. For additional instructions regarding Hartzell alternator instructions
for continued airworthiness, consult Section 10-4.3. Remove and replace all other
alternators with a new, rebuilt or serviceable alternators.
4. Install the serviceable alternator according to “Gear Driven Alternator Replacement,
Forward Mount” in Section 10-4.1 or “Gear Driven Alternator Replacement, Aft
Mount” in Section 10-4.2 after successfully completing the alternator

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manufacturer's service and inspection requirements. For belt driven alternator
installation, refer to the engine primary ICA (Ref: Section 1-1.1).
5. Perform the instructions in the normal “Engine Start” (Section 7-3.2) and “Ground
Run-up” (Section 7-3.3) to verify alternator operation.
6. Install airframe components and cowling according to the aircraft manufacturer's
instructions.
6-4.22.1. Alternator Drive Coupling Inspection FWD

Applicable Engines:
GTSIO-520-C, D, F, H, K, L, M, N, IO-520-B, BA, BB, C, CB, M, MB, NB, TSIO-520-B,
BB, BE, D, DB, E, EB, J, JB, K, KB, L, LB, N, NB, UB, VB, WB, IO-550-A, B, C, G, N,
P, R, IOF-550-B, C, N, P, R, TSIO-550- B, C,E, G, K, N, TSIOF-550-D, J, K, P, 
TSIOL-550, A, B, C
NOTE: This procedure only applies to the direct drive alternator. The
alternator drive coupling is designed to slip when abnormal torque is
required to rotate the alternator shaft.
Procedure
1. Remove the top spark plugs according to instructions in Section 6-4.9.2.
2. Remove the alternator according to the instructions in Section 10-4.2.1.
3. Perform a “Gear Tooth Inspection” according to instructions in Section 11-1.1 on
the alternator drive coupling gear and the crankshaft face gear.
a. Rotate the crankshaft 360° in order to inspect the circumference of the face gear.
NOTE: If the alternator drive coupling exhibits damage or missing
material, perform a “Foreign Object Contamination Inspection” according
to the instructions in Section 6-5.7. Remove the foreign material from the
crankcase and perform a visual inspection to determine if surrounding
components were damaged as a result of the component failure.
b. Inspect the drive coupling gear teeth for damage or missing material. If damage
to the drive coupling clutch is suspect, or damage is obvious, perform a “Foreign
Object Contamination Inspection” according to instructions in Section 6-5.7.
4. Alternator couplings with a drive spring assembly were superseded in 1996 by the
elastomer drive coupling. If the alternator is assembled with a drive spring assembly,
remove the drive spring assembly and replace it with an elastomer drive coupling
according to the instructions in Section 10-4.1.2 and Section 10-4.1.3.
NOTE: Do not remove the drive coupling for the slippage inspection.
Perform the drive coupling slippage inspection with the alternator drive
coupling installed and torqued, with the cotter pin intact on the shaft.
5. Inspect the exterior of the alternator for evidence of oil leakage; consult the
alternator service instructions for oil seal replacement instructions. If the oil seal
cannot be replaced, replace the alternator according to instructions in Section 10-4.

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6. Inspect the alternator drive coupling assembly for shearing or tearing of the
elastomeric (rubber) element. Replace worn or damaged parts observed according to
instructions in Section 10-4.1.3, “Alternator Drive Coupling Installation.”
CAUTION: Secure only the outer diameter of the drive coupling
assembly; allow the gear freedom of movement to prevent shearing
the elastomer coupling.
7. Perform an “Alternator Drive Coupling Slippage Inspection” with the coupling
installed on the alternator shaft according to the instructions in Section 10-4.1.4 on
the elastomer drive coupling.
8. Install the alternator according to the instructions in Section 10-4.1.5.
9. Install the top spark plugs according to instructions in Section 6-4.9.2.

Figure 6-104. Alternator Drive Coupling

6-4.22.2. Alternator Drive Coupling Inspection AFT

Subject engines may have a single piece elastomer coupling or a multi-part coupling.
Applicable Engines:
C-75, C-85, C-90, C-115, C-125, C-145, E-165, E-185, E-225, O-200, GO-300, GIO-300,
O-300, IO-240, IOF-240, IO-360, LTSIO-360, TSIO-360
NOTE: This procedure only applies to the direct drive alternator. The
alternator drive coupling is designed to slip when abnormal torque is
required to rotate the alternator shaft.
Procedure
1. Remove the top spark plugs according to instructions in Section 6-4.9.2.
2. Remove the alternator from the accessory case according to the instructions in
Section 10-4.2.1.
3. Perform a “Gear Tooth Inspection” according to instructions in Section 11-1.1 on
the alternator drive coupling gear and the camshaft gear.
a. Rotate the crankshaft through two complete revolutions while inspecting the
circumference of the camshaft gear.
b. Inspect the drive coupling gear teeth for damage or missing material. If damage
to the drive coupling is suspect, or damage is obvious, perform a “Foreign Object
Contamination Inspection” according to instructions in Section 6-5.7.

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4. Remove the alternator drive coupling according to instructions in Section 10-4.2.2.
NOTE: If the alternator drive coupling exhibits damage or missing
material, perform a “Foreign Object Contamination Inspection” according
to the instructions in Section 6-5.7. Remove the foreign material from the
crankcase and perform a visual inspection to determine if surrounding
components were damaged as a result of the component failure.
5. Identify the type of assembly installed and inspect the drive coupling.
a. Inspect the one piece alternator drive coupling assembly:
1) Inspect the assembly for shearing or tearing; pay particular attention to the
condition of the elastomeric (rubber) element. Replace the coupling if worn
or damaged according to Section 10-4.2.2 and Section 10-4.2.3 instructions.
CAUTION: Secure only the outer diameter of the drive coupling
assembly; allow the gear freedom of movement to prevent shearing
the elastomer coupling
2) Secure the alternator drive coupling assembly in a vise with protective
(padded) covers on the jaws. Do not over-tighten the coupling in the vise.
3) Install the Alternator Drive Hub Torque Tool (Figure 2-6) over the drive
coupling and apply 100 inch pounds of torque to the drive coupling with a
calibrated torque wrench. No slippage is permitted at 100 inch pounds of
torque or less. Replace the drive coupling if slippage occurs under 100 inch
pounds of torque.
4) Install the serviceable drive coupling on the alternator according to
instructions in Section 10-4.2.3.
b. Inspect the multi-part drive coupling:
1) Secure the alternator coupling gear (Figure 6-105, item 5) in the jaws of a
padded vice, leaving the gear section free.
NOTE: At 500 Hours, replace the retainer and bushings regardless of
condition, on the multi-piece couplings.
2) Remove the sleeve (6), bushings (8), and retainer (7). Do not remove the
drive coupling (1) unless damage is suspect. Discard the bushings (8) and
retainer (7).
3) Inspect the nut (3), gear (5) and sleeve (6) for wear and replace if necessary.
4) Install a new retainer (7) and two new bushings (8) in the coupling (1) on the
alternator shaft. Install the sleeve (6) and gear (5) on the shaft and secure with
the nut (3).
5) Install the drive coupling assembly according to instructions in Section 10-4.2.3.

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Figure 6-105. Alternator and Coupling Assembly

1 Drive Coupling 3 Castellated Nut 5 Gear 7 Retainer
2 Woodruff Key 4 Cotter Pin 6 Sleeve 8 Bushings

6. Install the alternator according to instructions in Section 10-4.2.4.

7. Install the top spark plugs according to instructions in Section 6-4.9.2.

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6-5. Unscheduled Maintenance
6-5.1. Propeller Strike
A propeller strike is any incident (whether or not the engine is operating) in which the
propeller contacts a foreign object that 1)results in the necessity to repair the propeller
blade(s) (other than minor blade dressing) or 2)results in loss of engine RPM at the time of
contact. Propeller strikes can cause engine and component damage even if the propeller
continues to rotate. This damage can result in catastrophic engine failure.
WARNING
Do not attempt to dress a propeller blade without consulting
the propeller manufacturer's instructions. Stresses imposed on
the propeller are more concentrated in areas that are nicked
and cut. They may act as stress risers. Stress risers weaken the
blade and can eventually cause the blade to fracture.
In cases where a small foreign object such as a small stone, strikes the propeller during
operation, inspect and repair the propeller according to the propeller manufacturer’s
instructions. If foreign object damage requires removal of the propeller for repair(s)
perform the “Propeller Strike Inspection” in Section 6-5.1.1.
6-5.1.1. Propeller Strike Inspection
Following any propeller strike, disassemble and inspect all rotating engine components
prior to further flight; correct all unserviceable conditions. Inspect all engine driven
components according to the manufacturer’s instructions for continued airworthiness.
Procedure
1. Remove the propeller; inspect according to propeller manufacturer’s instructions.
2. Remove the engine from the aircraft according to the instructions in Section 5-1.
3. Disassemble the engine completely according to instructions in the primary ICA
(reference Section 1-1.1).
4. Regardless of condition, replace all counterweight pins, bushings, end plates and
snap rings. Replace all connecting rod nuts and bolts, regardless of condition.
5. Thoroughly clean the crankshaft according to instructions in Chapter 12; all
surfaces, especially those forward of the front main bearing, must be free of paint,
sludge, or any substance that may mask cracks.
6. Perform a “Magnetic Particle Inspection” on the crankshaft, connecting rods, gears
and remaining steel internal engine parts according to instructions in Section 11-3.
7. Strip the crankcase of all paint and clean the crankcase thoroughly according to
instructions in Chapter 12; all surfaces must be free of paint, sludge, or any
substance that may mask reliable inspection.
8. Perform a “Fluorescent Penetrant Inspection” on the crankcase according to
instructions in Section 11-2, paying particular attention to the forward crankcase
bearing support and adjacent structure.
9. Inspect the remainder of the engine according to the instructions in the primary ICA
(Section 1-1.1).

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10. Perform the aircraft inspections required by the aircraft manufacturer.
11. Inspect all engine accessories according to the manufacturer’s instructions.
12. Assemble the engine according to instructions in the primary ICA (Section 1-1.1).
13. Install the engine in the aircraft according to the instructions in Section 5-2.
6-5.2. Hydraulic Lock Inspection
WARNING
Do not attempt to start an engine with an over-primed or
flooded induction system. Starting an engine with a flooded
induction system can result in hydraulic lock and subsequent
engine malfunction or failure. Allow excess fuel to drain from
the intake manifold and/or cylinder prior to attempting to start
the engine.

In the event the operator starts an over-primed/flooded engine
or suspects a hydraulic lock has occurred, perform the steps in
the inspection procedure below.
Hydraulic lock occurs when fluid accumulates in the induction system or the cylinder
assembly. The fluid restricts piston travel during the compression stroke. Engine damage
occurs when the other cylinders fire, forcing the piston in the fluid filled cylinder through
the compression stroke. Engine damage from hydraulic lock can be extensive due to the
high stresses generated, which can adversely affect connecting rods, pistons, cylinder
assemblies, piston pins, the crankcase, and crankshaft. Hydraulic lock may occur because
of any of the following:
• Restricted or improperly maintained induction system or cylinder intake port drains
• Extended operation of electric boost pump
• During failed engine start
• Following loss of power during ground operation
• Following momentary engine shutdown
• During single engine operation for training purposes on twin engine aircraft
• Over priming and attempting engine start with the aircraft parked on an incline that
negates the effective operation of the drain system
• Failure to properly remove preservative oil from an engine returned from storage
WARNING
Do not operate the engine if hydraulic lock is suspected.
Inspection Procedure
1. Remove the engine from the aircraft according to instructions in Section 5-1.
2. Disassemble the engine and remove all cylinders and connecting rods according to
instructions in the primary ICA (reference Section 1-1.1).

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3. Perform a “Connecting Rod Magnetic Particle Inspection” according to the
instructions in Section 11-3.1 and “Connecting Rod Dimensional Inspection”
according to the instructions in the primary ICA (Section 1-1.1). If all connecting
rods pass the inspection criteria, proceed to step 5; otherwise, continue to step 4.
NOTE: Destroy the stressed parts to prevent future installation.
4. If any connecting rod fails the inspection criteria, disassemble the engine completely
according to the instructions in the primary ICA (Section 1-1.1). Clean the
crankcase, cylinders and pistons according to instructions in the Chapter 12.
Perform Magnetic Particle, Fluorescent Penetrant and Ultrasonic Inspections, as
appropriate, on the crankshaft, crankcase and cylinder parts according to
instructions in Chapter 11. Perform the dimensional inspections for the crankcase
and crankshaft according to instructions in the primary ICA (Section 1-1.1). Replace
any part which fails the inspection criteria and destroy the faulty part(s).
5. Reassemble the engine according to instructions in primary ICA (Section 1-1.1).
6. Install the engine according to the instructions in Section 5-2.
6-5.3. Engine Overspeed Inspections
Operating an engine beyond its capacity can damage the engine and result in subsequent
engine failure. Engine overspeed severity is divided into three categories in Table 6-25:
Table 6-25. Overspeed Categories

Category (RPM)
I II III
Engine Model Rated RPM UP TO UP TO OVER
0-200, C-Series 2475-2800 3000 3300 3300
O-240, IO-240, IOF-240 2800 3000 3300 3300
0-300 2700 3000 3300 3300
GO-300 3200 3500 3700 3700
IO-346 2700 3000 3300 3300
IO-360, LTSIO-360, TSIO-360 2500-2800 3000 3300 3300
GIO-470 3200 3500 3700 3700
O-470, IO-470, TSIO-470 2400-2625 2900 3200 3200
GTSIO-520 3200-3400 3500 3700 3700
IO-520, LTSIO-520, TSIO-520 2400-2850 3000 3300 3300
IO-550, TSIO-550, TSIOF-550 2400-2850 3000 3300 3300
TIARA 6-285 4000 4100 4200 4200
TIARA 6-320 4400 4500 4600 4600
TSIOL-550 2600-2700 3000 3300 3300
NOTE: Rated RPM limits for aircraft equipped with digital RPM
measuring equipment may be adjusted to include a +2% deviation for
normal operations. Any operation beyond the rated RPM limit plus the
2% deviation must follow the inspection criteria.

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6-5.3.1. Category I Overspeed Inspection
If the duration of the overspeed event is less than ten seconds, no action is required. If the
overspeed event persists longer than 10 seconds, land the plane and perform the following
inspection:
Procedure
1. Drain oil and inspect for debris. Remove the oil filter (or screen) and inspect the
filter element for debris.
2. Remove the rocker covers and inspect the following for damage or debris:
a. Valves
b. Springs
c. Rocker arms
d. Tappets (lifters)
e. Spring retainers
f. Pushrods
3. Inspect components using the service limits in the primary ICA (Section 1-1.1);
repair and assemble the engine components according to instructions in the primary
ICA (Section 1-1.1).
4. Check accessory drives for excessive backlash.
5. Service the engine with new oil and oil filter according to instructions in Section 6-4.8.2.
6. If no discrepancies are noted, repeat Step 1 after five hours of accumulated flight.

6-5.3.2. Category II Overspeed Inspection

If the overspeed event duration is less than ten seconds, perform the Category I Inspection
and Service requirements specified in Section 6-5.3.1. If the overspeed event lasts longer
than 10 seconds, land the plane and perform the following inspection:
Procedure
1. Complete Category I inspection and service requirements.
2. Remove all cylinder assemblies, including pistons and rods.
3. Remove all counterweights (if applicable) (on TIARA, inspect the VTC unit).
4. Replace all connecting rod nuts and bolts, regardless of condition. Inspect removed
components using service limits and inspection instructions in the primary ICA
(Section 1-1.1) and assemble the engine according to instructions in the primary
ICA (Section 1-1.1).
5. If no discrepancies are noted, replace the engine oil and filter according to the
instructions in Section 6-4.8 after five hours of accumulated flight.

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6-5.3.3. Category III Overspeed Inspection
Overspeed conditions in this category are considered extreme. Category III overspeed
cases must be evaluated based on factors at the time of the incident. A Continental service
representative (see “Contact Information” in Section 1-3) will assist in determining
required actions to return the engine to an airworthy service condition.
Procedure
1. Remove the engine and clearly identify the reason for removal:
“Removed for Excessive Overspeed”
2. Perform a complete engine overhaul. Replace the following without regard to
overhaul inspection limits:
a. Connecting rods
b. Connecting rod bolts and nuts
c. All valve train components
6-5.4. Turbocharger Overboost
Erratic throttle movement, especially during takeoff and landing may cause the turbocharger
to exceed engine manifold pressure limits, a condition referred to as “overboost.” For
overboost below 3 in. Hg, slower throttle movement will prevent future occurrences.
1. Turbocharger overboost events between 3 and 6 in. Hg indicate a hardware
malfunction or improper control calibration. Troubleshoot the malfunction
according to instructions in Section 8-10 and correct before further flight.
2. Turbocharger overboost in excess of 6 in. Hg is an indication of a serious
malfunction. Engine damage is likely and must be assessed. Contact Continental
Customer Service Department for instructions (see “Contact Information” in
Section 1-3). Be prepared to provide details of event, including the duration of the
event and degree of overboost.
6-5.5. Lightning Strike Inspection
Procedure
1. Remove the engine(s) from the aircraft according to the instructions in Section 5-1.
2. Disassemble the engine(s) according to instructions in the primary ICA (reference
Section 1-1.1).
3. Inspect the engine(s) for arcing and heat damage to the crankshaft rod journals, main
journals, counterweights (if applicable), camshaft lobes, bearings, gear teeth, and all
other hardened surfaces. Perform a “Magnetic Particle Inspection” according to
instructions in Section 11-3 and degauss all steel parts of the engine(s) during the
inspection.
4. Perform dimensional inspections on the remaining parts using the instructions and service
limits in the primary ICA (reference Section 1-1.1). Replace all non-conforming parts.
5. Reassemble the engine(s) according to instructions and service limits in the primary
ICA (reference Section 1-1.1).
6. Install the engine(s) according to instructions in Section 5-2.

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6-5.6. Contaminated Fuel System Inspection
Engines described in this manual are certified for operation with the aviation fuel
specifications listed in the Type Certificate Data Sheet (TCDS) located on the FAA web
site. If the fuel tanks are filled with an improper grade of fuel but neither the aircraft boost
pump nor the engine is operated with the improper grade of fuel, purge the fuel tanks
according to the aircraft maintenance manual instructions. If the aircraft boost pump or the
engine are operated with an incorrect grade of aviation fuel or jet fuel:
Procedure
1. Do not fly the aircraft.
2. Drain and purge the aircraft fuel system according to the aircraft manufacturer's
instructions.
3. Remove the engine(s) from the aircraft according to the instructions in Section 5-1.
4. Disassemble, clean, and inspect the engine(s) according to instructions in the
primary ICA (Section 1-1.1). Replace any cylinder, piston, piston pin, connecting
rod or crankshaft exhibiting signs of detonation.
5. Reassemble and test the engine(s) according to instructions in the 
primary ICA (Section 1-1.1).
6. Install the engine(s) according to instructions in Section 5-2.
6-5.7. Foreign Object Contamination Inspection
Foreign Object Damage (FOD) occurs when material that wasn't included in the original
design contacts (internally or externally) and contaminates the engine. FOD can increase
friction, prohibit normal distance of travel, block oil passages, accelerate wear on contact
surfaces or cause immediate catastrophic failure of components or the entire engine. FOD
may be caused by external elements (i.e. sand, grit or metal shavings) or debris from
fractured internal components such as an improperly torqued fasteners.
WARNING
Exercise strict housekeeping standards when performing
aircraft and engine maintenance. Inventory tools before and
after performing maintenance. When replacing engine parts,
remove all remnants (safety wire, gasket material, o-rings,
fragmented parts, etc.) of the removed part from the engine
before installing the new part.
Procedure
1. Drain the engine oil and remove the oil sump from the crankcase.
2. Conduct a thorough inspection of the oil sump, crankcase, crankshaft, camshaft,
cylinder walls and pistons for the presence of, or damage caused by foreign objects.
a. If damage is discovered or any portion of the foreign material is not accounted
for: disassemble, clean, inspect, repair and assemble the engine according to
instructions and service limits in the primary ICA (Section 1-1.1).

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CAUTION: Disassemble and thoroughly inspect the entire engine
before assembly and return to service following a foreign object
contamination event. Minimum inspection requirements are
provided in step b if the owner/operator determines no foreign
material remains in the engine and elects to not perform a complete
inspection. Continental assumes no responsibility for engine
operation or airworthiness after a contamination event.
b. If 100% of the foreign material is retrieved from the oil sump and no further
material is discovered, clean the sump according to “Engine Cleaning”
instructions in the Chapter 12; install the oil sump, service the engine oil and
return the engine to service. Perform the next three oil changes at ten hour
intervals to confirm lack of foreign material in the oil.
3. Correct discrepancies discovered during the inspection. Do not return the engine to
service until the contamination is eliminated and appropriate repairs are made to
correct any discrepancies discovered during the inspection.
6-5.8. Sticking or Stuck Valves
Engines operated infrequently or engines consistently serviced with fuel containing high
levels of lead are prone to deposit buildup in the valve guide and/or the valve stem. If the
condition is ignored, the buildup may lead to sticking valves, or valve train damage.
If one or more valves in the valve train are sticking:
CAUTION: Removing cylinder flange nuts relieves the through-bolt
clamping force on the crankcase. Do not remove cylinder flange nuts
from more than one cylinder at a time. Do not turn the crankshaft
with through-bolt nuts removed. A rotational check will be
performed after cylinder installation to verify crankshaft main
bearing integrity in the crankcase.
1. Remove the cylinder from the engine according to the “Cylinder Removal”
instructions in Section 10-6.1.1.
a. Remove the valve keepers, springs, seats, and valves from the cylinder according
to the primary engine ICA.
b. Thoroughly clean the cylinder assembly and valve train components with mineral
spirits according to the instructions in Section 12-1.1.
c. Perform a visual and dimensional inspection of the valve guides according to the
service limits in the primary engine ICA.
d. Perform a visual and dimensional inspection of the valve face and stem according
to the service limits in the primary engine ICA. Verify the valve stem runout is
within service limits.
e. Perform a visual and dimensional inspection of the rocker arms according to the
service limits in the primary engine ICA. If the rocker arms meet the service
limits, perform a magnetic particle inspection on the rocker arms to verify the
sticking valves did not stress the rocker arms.

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f. Perform a visual and dimensional inspection of the pushrods according to the
service limits in the primary engine ICA. Inspect the pushrods for runout by
rolling them across a surface plate. Runout may not exceed service limits
published in the primary engine ICA.
g. Inspect the remaining cylinder parts according to the primary engine ICA.
2. Reassemble the cylinder components with new or serviceable parts, as applicable,
according to the instructions in the primary engine ICA.
3. Install and torque the cylinders according to the to the “Cylinder Installation” and
“Cylinder Torque” instructions in Section 10-6.1.2 and Section 10-6.1.2.
4. If cylinders are replaced, follow the “Engine Operation after Cylinder Replacement
and/or Major Overhaul” instructions in Section 7-2.3 for the first 25 hours of
operation after cylinder replacement.

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6-6. Inspection Checklists
Inspection checklists are included as a convenient record of inspection progress and
findings. Using a copy of the form ensures a blank form will be available for the next
scheduled inspection. When an inspection is due, make a copy of the inspection checklist
to record inspection progress and findings while following the steps in the inspection
procedures. The checklists are not designed to replace the procedures; only augment them.
File the completed checklists in the aircraft records.

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Table 6-26. Engine Operational Checklist

Aircraft Make & Model: Aircraft Registration #:
Engine Model: Engine Position: Left Right Front Rear
Engine Serial Number: Engine Total Time:NewOverhaul

Date Location: Elevation: Outside Air Temp.: Altitude:

Operational Check
RPM Magneto Drop Check MAP Cylinder Head Temp. - °F EGT TIT
Spec Actual L R Drop/Spread Spec Actual 1 2 3 4 5 6 °F °F

Adjustments
IDLE Fuel Pressure (psi) Full Power Fuel Pressure (psi) Oil
Adjustments Adjustments Pressure Temp. Adjustments
Spec Actual Spec Actual
CW CCW CW CCW PSI °F CW CCW

Check Flight Data

Pressure
Altitude EGT °F TIT °F CHT °F
RPM MAP Set altimeter to 29.92” Spec Actual Spec Actual Spec Actual

Fuel Flow Oil PSI Oil Temp. °F Indicated Airspeed

Spec Actual Spec Actual Spec Actual

Remarks:

Signature:

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Table 6-27. 25-Hour Initial Operation Inspection Checklist

Engine Model Number: ___________________ Engine Serial Number: _________________
Total Time Engine has been in Service: _______________
Time Since Major Overhaul (TSMOH): __________________ Engine in Storage? ________
Date Inspection Performed: ________ Inspection Performed by:_____________________
Complete the 25-hour inspection according to the instructions referenced in the table, heeding all warnings,
cautions and notes. Initial the block beside the procedure upon completion. Note discrepancies in the Inspector
Comments or Remarks sections.

Inspection Item Initials Inspector Comments

“Visual Inspection” (Section 6-4.6)
Check Oil Consumption (Section 6-4.2)
“Induction System Inspection” (Section 6-4.14)
“Induction System Drain Inspection”(Section 6-4.20)
Change Engine Oil and Filter (Section 6-4.8.2)
Engine Run (Section 7-3.2)
•Idle RPM:
•Idle Mixture Cutoff Rise
•Acceleration
Remarks:

Approval Block:

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Table 6-28. 50-Hour Engine Inspection Checklist

Engine Model Number: ___________________ Engine Serial Number: _________________
Total Time Engine has been in Service: _______________
Time Since Major Overhaul (TSMOH): __________________ Engine in Storage? ________
Date Inspection Performed: ________ Inspection Performed by:_____________________
Complete the 50-hour inspection according to the instructions referenced in the table, heeding all warnings, cautions
and notes. Initial the block beside the procedure upon completion. Note discrepancies in the Inspector Comments or
Remarks sections.

Inspection Item Initials Inspector Comments

Oil Consumption and Trend Monitoring
Collect oil sample (Section 6-4.8.4) and Establish Oil
Analysis Profile (Section 6-4.8.5)
Oil Analysis Laboratory used?
Date of last oil sample analysis:
Silicone content of last sample:
Oil consumption quantity noted during oil change:

Is oil consumption excessive? Yes No

“Visual Inspection” (Section 6-4.6)
Oil and Filter Change (Section 6-4.8.2)
“Induction System Inspection” (Section 6-4.14)
“Induction System Drain Inspection” (Section 6-4.20)
For specified turbocharged engines only, lubricate the
wastegate butterfly valve (Section 6-4.21) and clean the
turbocharger oil supply check valve (Section 6-4.21.1)
Engine Run (Section 7-3.2)
•Idle RPM:
•Idle Mixture Cutoff Rise
•Acceleration
Remarks:

Approval Block:

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Table 6-29. 100-Hour Engine Inspection Checklist
Engine Model Number: ___________________ Engine Serial Number: _________________
Total Time Engine has been in Service: _______________
Time Since Major Overhaul (TSMOH): __________________ Engine in Storage? ________
Date Inspection Performed: ________ Inspection Performed by:_____________________
Complete the 100-hour inspection according to the instructions referenced in the table, heeding all warnings,
cautions and notes. Initial the block beside the procedure upon completion. Note discrepancies in the Inspector
Comments or Remarks sections.

Inspection Item Initials Inspector Comments

Engine Operational Check(Section 6-4.7)
Oil Consumption and Trend Monitoring
Oil Analysis Profile Established? (Section 6-4.8.5)
Oil Analysis Laboratory used?
Date of last oil sample analysis:
Silicone content of last sample:
Oil consumption quantity noted during oil change:

Is oil consumption excessive? Yes No

“Visual Inspection” (Section 6-4.6)

Accessory Mounting and Security Inspection (Step 19 in

Section 6-4.4)

“Cylinder Inspections”(Section 6-4.11) using the

Cylinder Inspection Checklist (Table 6-31 on page 177)

“Crankcase Inspection”(Section 6-4.12)

“Engine Mount Inspection” (Section 6-4.13)
“Induction System Inspection” (Section 6-4.14)
“Ignition System Inspection” (Section 6-4.15)
“Engine Gauge Inspection” (Section 6-4.16)
“Fuel System Inspection” (Section 6-4.17)
“Engine Control Linkage Inspection” (Section 6-4.19)
“Induction System Drain Inspection”(Section 6-4.20)

“Turbocharger and Exhaust System Inspection”

(Section 6-4.21)

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Table 6-29. 100-Hour Engine Inspection Checklist
Engine Model Number: ___________________ Engine Serial Number: _________________
Total Time Engine has been in Service: _______________
Time Since Major Overhaul (TSMOH): __________________ Engine in Storage? ________
Date Inspection Performed: ________ Inspection Performed by:_____________________
Oil and Filter Change (Section 6-4.8.2)
Engine Operational Check (Section 6-4.7)
Remarks:

Approval Block:

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Table 6-30. 500-Hour Engine Inspection Checklist
Engine Model Number: ___________________ Engine Serial Number: _________________
Total Time Engine has been in Service: _______________
Time Since Major Overhaul (TSMOH): __________________ Engine in Storage? ________
Date Inspection Performed: ________ Inspection Performed by:_____________________
Complete the 500-hour inspection according to the instructions referenced in the table, heeding all warnings,
cautions and notes. Initial the block beside the procedure upon completion. Note discrepancies in the Inspector
Comments or Remarks sections.

Inspection Item Initials Inspector Comments

Engine Operational Check(Section 6-4.7)
Oil Consumption and Trend Monitoring
Oil Analysis Profile Established? (Section 6-4.8.5)
Oil Analysis Laboratory used?
Date of last oil sample analysis:
Silicone content of last sample:
Oil consumption quantity noted during oil change:

Is oil consumption excessive? Yes No

“Visual Inspection” (Section 6-4.6)

Accessory Mounting and Security Inspection (Step 19

in Section 6-4.4)

Paper Induction Filter Replacement (Section 6-4.5)

“Cylinder Inspections”(Section 6-4.11) using the

“Cylinder Inspection Checklist” (Table 6-31)

“Crankcase Inspection”(Section 6-4.12)

“Engine Mount Inspection” (Section 6-4.13)
“Induction System Inspection” (Section 6-4.14)
“Ignition System Inspection” (Section 6-4.15)

500-Hour (Continental) Magneto Inspection or (non-

Continental) Magneto Replacement (Section 6-4.15)

“Engine Gauge Inspection” (Section 6-4.16)

“Fuel System Inspection” (Section 6-4.17)

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Table 6-30. 500-Hour Engine Inspection Checklist
Engine Model Number: ___________________ Engine Serial Number: _________________
Total Time Engine has been in Service: _______________
Time Since Major Overhaul (TSMOH): __________________ Engine in Storage? ________
Date Inspection Performed: ________ Inspection Performed by:_____________________
“Engine Control Linkage Inspection” (Section 6-4.19)
“Induction System Drain Inspection”(Section 6-4.20)

“Turbocharger and Exhaust System Inspection”

(Section 6-4.21)

“Alternator Inspection” (Section 6-4.22)

Oil and Filter Change (Section 6-4.8.2)
Engine Operational Check (Section 6-4.7)
Remarks:

Approval Block:

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Table 6-31. Cylinder Inspection Checklist

Engine Model Number: ___________________ Engine Serial Number: _________________
Total Time Engine has been in Service: _______________
Time Since Major Overhaul (TSMOH): __________________ Engine in Storage? ________
Date Inspection Performed: ________ Inspection Performed by:_____________________
Inspection Item Inspector Comments
Complete the cylinder inspection according to the instructions referenced in the table, heeding all warnings,
cautions and notes. Initial the block beside the procedure upon completion. Note discrepancies in the Inspector
Comments or Notes sections.

Complete a visual inspection of the cylinder exterior and power

stroke areas for signs of cracks, leaks, rust or 
pitting (Section 6-4.11.1).
Cylinders
1 2 3 4 5 6
     
Complete a visual inspection of cylinder head, barrel, fins, ports
and bosses for evidence of fuel, oil or soot (Section 6-4.11.1)

Cylinders
1 2 3 4 5 6
     
Inspect the cylinder to crankcase mounting deck for visible signs
of RTV sealant (Section 6-4.11.4).

Cylinders
1 2 3 4 5 6
     
Differential Pressure Check (Section 6-4.11.2)
Baseline Master Orifice Calibrated Pressure Reading:

Cylinder Pressure Reading

1 2 3 4 5 6
     
NOTES:

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Table 6-31. Cylinder Inspection Checklist
Engine Model Number: ___________________ Engine Serial Number: _________________
Total Time Engine has been in Service: _______________
Time Since Major Overhaul (TSMOH): __________________ Engine in Storage? ________
Date Inspection Performed: ________ Inspection Performed by:_____________________
Cylinder Borescope Findings (Section 6-4.11.3)
Place a check mark in the column of any cylinder exhibiting the characteristics described in the left column.

Condition 1 2 3 4 5 6
Normal Wear.      
Light rust (acceptable in absence of
excessive oil consumption or leaks)      
Small areas of heavy rust (less than
½ inch diameter)      
Heavy rust (greater than ½ inch)      
Pitting of on cylinder wall.      
Heavy wear      
Scoring      
Static seal leakage      
Other discrepancies      
Cylinder Inspection Summary
Place a check mark in the column of any cylinder exhibiting the characteristics described in the left column.
Cylinders exhibiting the following characteristics must be removed and repaired or replaced according to the
instructions in Section 10-6, “Cylinder Repairs.”

Condition 1 2 3 4 5 6
Heavy rust, characterized by pitting
of the cylinder wall      
Scoring or scratches in the honed
surface of the cylinder wall (or bore)      
Blistered paint on the cylinder
barrel/other evidence of excessive
wear and internal heat
     
Cylinder subjected to overheating/
detonation/piston scoring or piston
pin damage to the cylinder bore.
     
Cylinder with radial fin crack
extending to the root of a fin      
Cylinder with barrel fin crack      
Cylinder head turned in relation to
barrel flange      
Page 2 of 3

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 Engine Inspection and Service
Table 6-31. Cylinder Inspection Checklist
Engine Model Number: ___________________ Engine Serial Number: _________________
Total Time Engine has been in Service: _______________
Time Since Major Overhaul (TSMOH): __________________ Engine in Storage? ________
Date Inspection Performed: ________ Inspection Performed by:_____________________
Condition 1 2 3 4 5 6
Heavy bore wear      
Cylinder leaks      
Low differential pressure/ excessive
oil consumption      
Static seal leakage/head to barrel      
leakage, or crack in head or barrel
     
Inspection Follow-up
Check all column(s) that apply to the scope of inspection and repair.

Condition 1 2 3 4 5 6
Cylinder passed inspection      
Repaired Cylinder      
Replaced Cylinder      
Remarks:

Approval Block:

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 Engine Operation
Chapter 7. Engine Operation
7-1. Introduction
This chapter contains the engine ground operating instructions applicable to all engines to
facilitate maintenance personnel during:
• Normal Engine Operation
• Engine Operation in Abnormal Environments
Instructions in this chapter apply to Continental engines conforming to the original type
design and supplements information in the Airplane Flight Manual (AFM) or Pilot's
Operating Handbook (POH) provided by the aircraft manufacturer or supplemental type
certificate holder as required by the Federal Aviation Regulations (FAR) for aircraft
operating procedures.
CAUTION: This chapter pertains to engine operations under various
operating conditions. Normal operating instructions are presented
first followed by operation in adverse operating environments.
7-2. Flight Prerequisites
If the engine is newly installed and/or has been repaired/overhauled, perform an “Engine
Operational Check” according to instructions in Section 6-4.7 prior to releasing the engine
for normal operation.
WARNING
DO NOT FLY THE AIRCRAFT UNTIL ALL FLIGHT
PREREQUISITES HAVE BEEN MET.
The “Engine Operational Check” in Section 6-4.7 must be
completed on an engine that has been installed, inspected,
repaired, or overhauled before the aircraft can be released for
normal operation.
NOTE: Environmental conditions (humidity), seasonal changes, and
engine usage influence susceptibility to corrosion. Engines that are flown
occasionally (less than one time per week) are more vulnerable to
corrosion under these conditions. The best method of reducing the risk of
corrosion is to fly the aircraft weekly for at least one hour. The owner/
operator is ultimately responsible for recognizing corrosion and taking
appropriate corrective action.
After successful completion of the Engine Operational Check, perform a Flight Check
according to instructions in Section 7-2.4.2.
7-2.1. Oil Change Interval
NOTE: After the first 25 hours of operation, perform an oil change
according to the “Engine Oil Servicing”instructions in Section 6-4.8.
The Oil Change Interval is specified in Table 6-2, “Engine Inspection and Maintenance
Schedule.”

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Engine Operation
7-2.2. Engine Fuel Requirements
WARNING
Aircraft engines are certified for operation with specific
aviation fuels. Authorized fuels are recorded on the engine
Type Certificate Data Sheet (TCDS). If the minimum fuel grade
is not available, use the next higher grade. Never use a lower
grade fuel. The use of lower octane fuel may result in damage
to, or destruction of, an engine. Any engine operating on fuel of
a lower grade than approved by the engine type certificate must
be completely disassembled for inspection.
WARNING
Continental does not recommend or authorize the use of
automotive fuels in aircraft engines. The engine warranty and
pro rata policy will be voided if such fuels are utilized.
The fuel used in aircraft and aircraft engines is an integral part of the certification process.
Service the aircraft only according to the instructions in the AFM/POH, which are based
on the engine fuel specifications authorized by the TCDS. Some engines were certified for
operation with fuel grades that are no longer available. A complete list of certified engines
and the fuels authorized for operation, by engine model, is provided in Table 7-2. If the
aircraft is inadvertently serviced with the incorrect grade of aviation fuel or jet fuel, the
fuel system must be completely drained and the fuel tanks serviced in accordance with the
aircraft manufacturer's recommendations. The use of automotive fuels is prohibited in all
Continental aircraft engines. After the fuel system is decontaminated, inspect the engine
according to “Contaminated Fuel System Inspection” instructions in Section 6-5.6.
CAUTION: Follow the aircraft manufacturer’s instructions
applicable to the use of fuel additives.
Under certain ambient conditions of temperature and humidity, sufficient quantities of
water may exist in the fuel to create restrictive ice formation in the fuel supply. To
alleviate this occurrence, it is permitted to add no more than three percent Isopropyl
Alcohol1 or Diethylene Glycol Monomethyl Ether (DiEGME) conforming to military
specification MIL-DTL-85470B, if approved by the aircraft manufacturer, may be added
to the fuel supply for this purpose. Refer to Section 3-3.
Aviation Fuel Specifications are regulated by both International and National regulations.
In the United States, the American Society for Testing and Materials (ASTM) is the basis
for fuel specification. Some countries have bilateral agreements to accept and utilize the
ASTM standards. While a comprehensive list of all countries’ specifications is impractical
for this manual, the regional specifications for which Continental engines are certified are
listed in Table 7-2.

1. Because isopropyl alcohol is normally added at the point of use, the operator is cautioned that it may impact octane perfor-
mance. Depending on octane grade, the isopropyl alcohol additive may increase or decrease the fuel octane rating. Consult the
respective fuel specification and the airframe manufacturer’s instructions regarding fuel additives.

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 Engine Operation
Table 7-1. Aviation Fuel Specifications
Fuel Specification Fuel Grades Color
1) Green
100 (100/130
100LL Blue
ASTM D910 - Standard Specification for Aviation Gasolines 100VLL Blue
80 (80/871) Red
91 (91/961) Brown
ASTM D7547 - Standard Specification for Hydrocarbon Unleaded UL91 Colorless
Aviation Gasoline UL942 Colorless
GOST 1012 - Aviation Petrol B95/130 Amber
Russian Federation of States B91/115 Green
GB 1787 - Aviation Piston Engine Fuels 95 (RH95/130)
Saffron
People’s Republic of China 100 (RH100/130)
1. Inactive - consult the latest revision of ASTM D910.
2. ASTM 7547/UL94 is acceptable for use on aircraft and engines certificated for operation with ASTM 7592/UL94 - reference FAA SAIB
HQ-16-05

NOTE: Continental engines previously certified for operation with 91/96

octane or grade 100/130 aviation gasoline will operate satisfactorily on
Grade 100LL. It is recommended that Grade 100LL be used in these
engines because of the reduction in combustion chamber deposits realized
with the lower tetraethyl lead content.
Table 7-2. Authorized Fuels by Engine Model

Current
Certified Fuel Alternate
Engine Model on Type Certificate Authorization
NOTE: Engine operation with RH95/130 and UL94 fuel may limit
engine performance, operating ceiling, and/or maximum
recommended cruise power. Consult the engine specifications and
operating limits section of the primary ICA for amplification.
A-65, A-75 80/87 100LL
C-75, C-85, C-90, C-125, C-145 80/87 100LL
E-165, E-185, E-225 80/87 100LL
O-200-A, B 80/87 100LL
O-200-D, X 100/100LL, RH100/130 N/A
100/100LL, B95/130,
IO-240-A, B N/A
RH95/130
100/100LL, B95/130,
IOF-240-B N/A
RH95/130
O-300, GO-300 80/87 100LL
IO-360-A, AB, C, CB, D, DB, E, ES, G, GB, H, HB, 100/100LL, B95/130,
N/A
J, JB, K, KB RH95/130
IO-360-B 80/87 100/100LL

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Engine Operation
Table 7-2. Authorized Fuels by Engine Model

Current
Certified Fuel Alternate
Engine Model on Type Certificate Authorization
NOTE: Engine operation with RH95/130 and UL94 fuel may limit
engine performance, operating ceiling, and/or maximum
recommended cruise power. Consult the engine specifications and
operating limits section of the primary ICA for amplification.
100/100LL/100VLL,
IO-360-AF UL91, UL94, B95/130, N/A
RH95/130
TSIO-360-A, AB, B, BB, C, CB, D, DB, E, EB, F,
FB, G, GB, H, HB, JB, KB, LB, MB, NB, PB, SB; 100/100LL N/A
LTSIO-360-E, EB, KB
TSIO-360-RB; 100/100LL, B95/130,
N/A
LTSIO-360-RB RH95/130
IO-346 91/96 100/100LL
O-470-4, 11, 13, 15 80/87 100LL
O-470-A, F, J, K, L, R & S 80/87 100LL
O-470-B, G, H, M, N & P 91/96 100/100LL
O-470-T & U 100LL 100/100LL
LIO-470, IO-470-A, C, G, P & T 91/96 100/100LL
IO-470-D, E, F, H, L, M, N, S, U, V & VO
100/130 100/100LL
GIO-470; TSIO-470
100/100LL, RH95/130,
IO-520-A, B, BA, BB, C, CB, J, M, MB N/A
or B95/130
100/100LL,
IO-520-D, E, F, K, L, N, NB N/A
B95/130
GTSIO-520 100/130 100/100LL
100/100LL,
LIO-520 N/A
B95/130
TSIO-520 100/130 100/100LL
TIARA 6-285, 6-320 100/130 100/100LL
IO-550-A, B, C, G, N, P & R; 100/100LL, RH95/130,
N/A
IOF-550-A, B, C, G, N, P & R or B95/130
IO-550-D, E, F, L 100/100LL, RH95/130,
N/A
IOF-550-D, E, F, L or B95/130
TSIO-550-A 100/100LL N/A
100/100LL, RH95/130,
TSIO-550-B N/A
or B95/130
100/100LL, RH95/130,
TSIO-550-C, E, G, N N/A
or B95/130
100/100LL, RH95/130,
TSIO-550-K N/A
or B95/130, UL94

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 Engine Operation
Table 7-2. Authorized Fuels by Engine Model

Current
Certified Fuel Alternate
Engine Model on Type Certificate Authorization
NOTE: Engine operation with RH95/130 and UL94 fuel may limit
engine performance, operating ceiling, and/or maximum
recommended cruise power. Consult the engine specifications and
operating limits section of the primary ICA for amplification.
100/100LL, RH95/130,
TSIOF-550-D, J, K & P N/A
or B95/130
TSIOL-550-A, B, C 100/100LL N/A

Some older engine models, originally certified for use with 80/87 grade fuels, particularly
low compression ration engines may experience lead build-up or spark plug fouling as a
result of the higher octane and lead content of 100/100LL. Engines most affected by the
higher octane include the A-65, A-75, C-75, C-85, C-90, C-125, C-145, O-200, O-300 and
GO-300 engine series. Compliance with the instructions in Section 10-6.12 on these
engines will improve engine operation with the higher grade fuels.
Spark plug lead fouling increases when higher leaded fuels are used in engines originally
certificated on 80/87 octane fuel. Such fouling can be reduced by more frequent spark
plug cleaning and spark plug rotation. Fine wire spark plugs that are FAA approved for
use in those engines listed may further alleviate fouling problems. In any case, the rotation
of plugs every 50 hours of operation and cleaning/rotation every 100 hours is
recommended. A ground run at 800 to 1000 RPM of 60 to 90 seconds duration just prior to
shutdown will allow temperature stabilization and burn off of deposits accumulated during
descent and taxiing. Mixture cutoff should be accomplished at this RPM without returning
to idle.
Exhaust valve sticking can result from lead salt (sulfated ash) accumulation in the
lubricating oil. It is recommended that regular 50 hour oil changes be implemented to
reduce such accumulation. A few stuck exhaust valves have been reported where
examination of the cylinder assembly revealed an exhaust leak between the exhaust elbow
flange and the exhaust port face. This condition created localized cylinder head
overheating and subsequent exhaust valve and guide distress. The exhaust system should
be inspected every 100 hours and leaks corrected prior to continued engine operational
service.
Refer to the mixture leaning procedures in the AFM/POH to limit lead accumulation on
low compression engines originally certified for 80/87 octane fuel.

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Engine Operation
7-2.3. Engine Operation after Cylinder Replacement and/or Major Overhaul
NOTE: Instructions within this section apply to steel, nitrided, through-
hardened, or chrome plated cylinders. For engine operating instructions
with nickel silicon carbide (NiC3) plating, refer to the operating
instructions in the latest revision of SB15-6.
Proper operation of the engine following cylinder replacement or major overhaul is
extremely important. The following procedures should be followed to ensure that
adequate lubrication is being provided to newly installed components and that the piston
ring seating will occur as soon as possible.
1. Operation after Major Overhaul, Utilizing an Engine Test Cell:
a. Servicing and Pre-starting Procedures
1) Service the lubricating system with mineral oil of the appropriate grade
depending on ambient temperature (Section 3-1).
2) Rotate the propeller by hand through several cycles with the spark plugs
removed.
3) Pre-oil the lubrication system using an external pre-oiling pressure system
according to the instructions in Section 5-2.9. Spark plugs are installed
during the pre-oiling instructions.
b. Test Cell Operational Procedure
1) Perform the Post-Overhaul testing according to the instructions in the engine
primary ICA (Ref: Section 1-1.1).
2. Operation after Major Overhaul, Utilizing The Aircraft (in lieu of an engine test
cell):
The aircraft can be considered a suitable test stand for running-in overhauled
engines contingent on the following conditions.
a. Install engine cowling.
b. Each cylinder should be equipped with a temperature sensing device to monitor
the head temperature. If the aircraft cylinder head temperature gauge monitors
one cylinder, the following precaution must be adhered to:
During ground runs do not permit monitored head temperatures to exceed
400°F or oil temperature to exceed 200°F.
c. The flight propeller may be used contingent on careful observation of cylinder
temperatures. Head the aircraft into the wind for this test.
d. Calibration of the aircraft engine instruments must be performed.

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 Engine Operation
3. Operation after New Cylinder Installation or Cylinder Overhaul:
CAUTION: Corrosion preventive mineral oil MIL-C-6529 can be
used but must not be used after the first 25 hours, or six months,
whichever occurs first as this oil can cause coking with extended use.
a. Service the lubricating system with mineral oil of the appropriate grade
depending on ambient temperature (Section 3-1).
b. Ensure all engine and cylinder baffling is serviceable and properly installed.
c. Start the engine and verify oil pressure rises to within the specified limits within
30 seconds.
d. Operate the engine at 750 RPM for one minute; gradually increasing toward 1000
RPM in three minutes. Check the magneto circuit for grounding prior to a normal
shut-down. Allow the engine to cool adequately and then perform a visual
inspection for any irregularities.
e. Start the engine again and operate it at 750 RPM; gradually increasing to 1500
RPM over a period of four minutes.
1) If the engine is equipped with a controllable pitch propeller, cycle the
propeller allowing only a 100 RPM drop.
2) Return to the idle range and make adjustments to the idle mixture and RPM
as required on carburetor engines and to the low unmetered fuel pressure, idle
RPM, and mixture on fuel injected engines.
3) Position the throttle to 1200 RPM to smooth the engine. Then, perform an
idle mixture rise check. For continuous flow fuel injection systems, refer to
Section 6-4.7 for fuel system specifications. For engines equipped with
carburetors, refer to the primary ICA.
4) Run engine up to full power for a period not to exceed 10 seconds. Visually
inspect and correct any discrepancies. Check the oil level and service if
required.
5) Install aircraft accessories and cowling according to the aircraft
manufacturer’s instructions.
f. Perform a “Flight Check” and “Engine Break-In” according to the instructions in
Section 7-2.4.2 and Section 7-2.4.1.

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Engine Operation
7-2.4. Flight Check and Break-In
New and factory rebuilt Continental engines are adjusted to meet engine specifications in
a test cell prior to shipment. A flight check ensures the engine meets operational
specifications after installation in the airframe and prior to release for normal service.
Perform an “Engine Operational Check” according to instructions in Section 6-4.7 and a
normal preflight, engine start and ground run-up in accordance with the Airplane Flight
Manual or Pilot's Operating Handbook (AFM/POH) before the A&P mechanic can
approve the airplane for a Flight Check.
A flight check is required for engines with a standard fuel pump if rated, full power RPM
cannot be verified during a ground run-up according to instructions in Section 7-2.4.2
after engine installation, inspection, fuel system repairs, or adjustments. Additionally,
engines with an altitude compensating fuel pump require a “Flight Check” according to
instructions in Section 7-2.4.2 after a significant change in geographic location from the
last operational check (or if the auto-leaning function is suspect) and at twelve month
intervals, in conjunction with the Annual/100-hour inspection.
Follow the protocol in Section 7-2.4.1 to complete the recommended break-in period.
7-2.4.1. Engine Break-In
CAUTION: High power ground operation resulting in cylinder and
oil temperatures exceeding normal operating limits can be
detrimental to cylinders, pistons, valves, and rings.
The recommended break-in period for Continental engines is 25 hours. Adhere to the
following instructions and the Engine Specifications and Operating Limits in the primary
Instructions for Continued Airworthiness (Section 1-1.1) applicable to the engine model.
NOTE: Keep flying weight to a minimum to reduce power requirements.
1. For the initial flight after release to service, fast idle (850-1,000 RPM) engine for 3-4
minutes. Shut down and inspect for oil leaks. During ground runs, do not permit
cylinder head temperatures to exceed 400°F or oil temperature to exceed 200°F.
2. Conduct a normal engine start, ground run-up and take-off according to the AFM/
POH (minimize ground time).
3. Monitor a) engine RPM, b) fuel flow and pressure (if equipped), c) oil pressure and
temperature, d) cylinder head temperature (if equipped), e) exhaust gas temperature
(if equipped), and f) turbine inlet temperature (if equipped) to verify the engine is
operating within the parameters specified in the primary Instructions for Continued
Airworthiness (Section 1-1.1).
4. Reduce the engine speed to climb power according to the AFM/POH instructions.
Maintain a shallow climb attitude to achieve optimum airspeed and cooling airflow.
5. At cruise altitude:
a. Maintain level flight cruise at 75% power with best power or richer mixture for
the first hour of operation.
b. For the second and subsequent hours of flight, alternate cruise power settings
between 65% and 75% power with appropriate best power mixture settings.

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 Engine Operation
NOTE: Best power mixture setting is 100°-150°F (38°-66°C) rich of peak
exhaust gas temperature. Adjust engine controls or aircraft attitude to
ensure engine instrumentation operates within specifications.
WARNING
Avoid long descents at high engine RPM to prevent undesirable
engine cooling. If power must be reduced for long periods,
adjust the propeller to minimum governing RPM to obtain
desired performance levels. If outside air temperature is
extremely cold, it may be desirable to increase drag to maintain
engine power without gaining excess airspeed. Do not permit
cylinder head temperature to drop below 300°F (149°C).
6. Descend at low cruise power settings. Avoid long descents or descents at cruise
power RPM with manifold pressure below 18 in. Hg. If necessary, reduce engine
RPM to the lower limit of the specified operating range to maintain sufficient
manifold pressure. Carefully monitor engine instrumentation to maintain levels
above the minimum specified cylinder head temperature and oil temperature.
7. Correct any discrepancies prior to releasing the aircraft for service.

7-2.4.2. Flight Check

Flight check instructions vary, depending on fuel system configuration, naturally aspirated
engines with a carburetor:
• For Continental continuous flow fuel injection systems without altitude compensating
fuel pump, or turbocharged engines regardless of fuel system configuration, follow the
Standard Flight Check Instructions in Section 7-2.4.2.1.
• For naturally aspirated engines with Continental continuous flow fuel injection
systems with an altitude compensating fuel pump, follow the Flight Check instructions
in Section 7-2.4.2.2.
• For FADEC equipped engines, refer to the flight check in the primary ICA.
7-2.4.2.1. Standard Flight Check Instructions
NOTE: The accuracy of tachometer and fuel flow indicating device (if
equipped) is critical to the outcome of the flight check. Verify tachometer
and flow meter accuracy according to the aircraft manufacturer’s
instructions prior to performing the flight check.
1. Conduct a normal engine start, ground run-up and take-off according to the AFM/
POH.
2. Monitor a) engine RPM, b) fuel flow and pressure (if equipped), c) oil pressure and
temperature, d) cylinder head temperature (if equipped), e) exhaust gas temperature
(if equipped), and f) turbine inlet temperature (if equipped) to verify the engine is
operating within the parameters specified in the AFM/POH.
3. If the engine fails to reach the rated, full throttle RPM during ground operations,
ascend to cruise altitude (>2000 feet above field elevation) and verify the engine
achieves full throttle, full rich rated RPM at cruise altitude and operates within the

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Engine Operation
limits specified in the AFM/POH; if the engine meets full power, rated RPM,
proceed to step 4. If the aircraft indicated values fail to meet the published limits,
repeat the Engine Operational Check and Flight Check.
WARNING
All abnormal conditions must be corrected prior to releasing
the aircraft to normal operation.
4. Release the engine to normal service.
7-2.4.2.2. Flight Check for Continental Continuous Flow Fuel Injection Systems
with Altitude Compensating Fuel Pump
NOTE: For engines equipped with Bendix/Precision servo controlled
Fuel Systems with automatic density controllers, consult the primary ICA
or AFM/POH for Flight Check instructions.
NOTE: The accuracy of tachometer and fuel flow indicating device (if
equipped) is critical to the outcome of the flight check. Verify tachometer
and flow meter accuracy according to the aircraft manufacturer’s
instructions prior to performing the flight check.
1. Conduct a normal engine start, ground run-up and take-off according to the AFM/
POH.
2. Monitor a) engine RPM, b) fuel flow and pressure (if equipped), c) oil pressure and
temperature, d) cylinder head temperature (if equipped), e) exhaust gas temperature
(if equipped) to verify the engine is operating according to the parameters specified
in the AFM/POH.
3. Set altimeter to 29.92 in. Hg.
4. Navigate the aircraft to an area of low air traffic density. Ascend to the minimum
pressure altitude which offers unobstructed straight and level flight within the altitude
scale presented in the table applicable to the subject engine model shown in Section 7-
2.4.2.3. Record the altitude and corresponding fuel flow at 1000 ft. intervals depicted
in Section 7-2.4.2.3 charts on a copy of the “Engine Operational Checklist” on page 6-
167 of this manual.
RESULT:
a. If the engine RPM and full power fuel flow meet the specifications depicted in
the Altitude Leaning Schedule for engines equipped with altitude compensating
fuel pumps, proceed to step 5.
b. If the engine fails to meet the operating specifications, repeat the “Engine
Operational Check” in Section 6-3.7 and make necessary adjustments according
to the “Fuel System Adjustment” and “Auto Leaning Schedule Adjustments”
instructions in Section 6-3.10.2 and Section 6-3.10.3, respectively.
WARNING
All abnormal conditions must be corrected prior to releasing
the aircraft to normal operation.
5. Release the engine to normal service.

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7-2.4.2.3. Altitude Compensating Fuel System Auto-Leaning Schedules
Table 7-3. IO-360-D/DB Engine Altitude Leaning Schedule
Full Throttle RPM, Full Rich Mixture @ 2800 RPM
Fuel Flow Fuel Flow Metered Fuel
Pressure Altitude (lbs/hr) (gals/hr) Pressure PSID
(Set Altimeter at 29.92 in. Hg.) Min. Max. Min. Max. Min. Max.
Sea Level 102.9 112.9 17.5 19.2 16.0 18.8
1,000 98.4 108.4 16.8 18.5 15.0 17.8
2,000 94.1 104.1 16.0 17.7 14.1 16.8
3,000 90.0 100.0 15.3 17.0 13.3 15.9
4,000 86.1 96.1 14.7 16.4 12.6 15.1
5,000 82.3 92.3 14.0 15.7 11.9 14.4
6,000 78.8 88.8 13.4 15.1 11.3 13.7
8,000 72.2 82.2 12.3 14.0 10.2 12.5
10,000 66.4 76.4 11.3 13.0 9.3 11.5
12,000 61.3 71.3 10.4 12.1 8.6 10.7
14,000 56.9 66.9 9.7 11.4 8.0 10.0
16,000 53.3 63.3 9.1 10.8 7.5 9.5
Gasoline = 5.87 lbs per gallon @ 70 F.
IO-360-DB installed in T-41 aircraft, Refer to Cessna SL81-2, dated July 1981 for amplified instructions
120
Fuel - 100/100LL
Full Rich, 2700 RPM
Fuel Temp 70°
110

100

90
Fuel Flow (PPH)

80

70

60

50
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Pressure Altitude (X1000 ft)

Figure 7-1. IO-360-D/DB Altitude Leaning Schedule

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Engine Operation
Table 7-4. IO-360-ES Engine Altitude Leaning Schedule
Full Throttle RPM, Full Rich Mixture @ 2800 RPM
Fuel Flow Fuel Flow Metered Fuel
Pressure Altitude (lbs/hr) (gals/hr) Pressure PSID
(Set Altimeter at 29.92 in. Hg.) Min. Max. Min. Max. Min. Max.
Sea Level 100.0 107.0 17.0 18.1 14.3 16.5
1,000 97.7 103.7 16.6 17.7 13.9 15.8
2,000 93.7 99.7 16.0 17.0 13.1 14.9
3,000 9.3 96.3 15.4 16.4 12.3 14.1
4,000 87.3 93.3 14.9 15.9 11.7 13.6
5,000 85.0 91.0 14.5 15.5 11.5 13.2
6,000 83.3 89.3 14.2 15.2 11.1 12.8
8,000 80.0 86.0 13.6 14.7 10.6 12.2
10,000 77.3 83.3 13.2 14.2 10.1 11.8
12,000 74.4 80.4 12.7 13.7 9.6 11.2
14,000 71.3 77.3 12.1 13.2 9.2 10.7
16,000 69.3 75.3 11.8 12.8 8.9 10.3
Gasoline = 5.87 lbs per gallon @ 70 F.
110

Fuel - 100/100LL
Full Rich, 2700 RPM
Fuel Temp 70°
100

90
Fuel Flow (PPH)

80

70

60

50
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Pressure Altitude (X1000 ft)

Figure 7-2. IO-360-ES Altitude Leaning Schedule

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 Engine Operation
Table 7-5. IO-360-ES (Cirrus SR20) Engine Altitude Leaning Schedule
Full Throttle RPM, Full Rich Mixture @ 2700 RPM
Fuel Flow Fuel Flow Metered Fuel
Pressure Altitude (lbs/hr) (gals/hr) Pressure PSID
(Set Altimeter at 29.92 in. Hg.) Min. Max. Min. Max. Min. Max.
Sea Level 96.0 102.0 16.4 17.4 13.8 15.5
1,000 94.5 99.7 16.0 17.0 13.3 15.0
2,000 89.5 95.7 15.3 16.3 12.5 14.2
3,000 86.3 92.3 14.7 15.7 11.9 13.5
4,000 83.3 89.3 14.2 15.2 11.4 13.0
5,000 81.0 87.0 13.8 14.8 11.0 12.5
6,000 79.3 85.3 13.5 14.5 10.7 12.2
8,000 76.0 82.0 12.9 14.0 10.2 11.7
10,000 73.3 79.3 12.5 13.5 9.7 11.2
12,000 70.4 76.4 12.0 13.0 9.3 10.7
14,000 67.3 73.3 11.5 12.5 8.8 10.2
16,000 65.3 71.3 11.1 12.1 8.6 9.9
Gasoline = 5.87 lbs per gallon @ 70 F.
110

Fuel - 100/100LL
Recommended Setup for
Full Rich, 2700 RPM
Cirrus SR20 Installation
Fuel Temp 70°
100 2700 RPM @ WOT

90
Fuel Flow (PPH)

80

70

60

50
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Pressure Altitude (X1000 ft)

Figure 7-3. IO-360-ES in Cirrus SR20 Altitude Leaning Schedule

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Engine Operation
Table 7-6. IO-550-A Engine Altitude Leaning Schedule
Full Throttle RPM, Full Rich Mixture 300 BHP @ 2700 RPM
Fuel Flow Fuel Flow Metered Fuel
Pressure Altitude (lbs/hr) (gals/hr) Pressure PSID
(Set Altimeter at 29.92 in. Hg.) Min. Max. Min. Max. Min. Max.
Sea Level 142 150 24.2 25.6 16.5 17.2
1,000 141 149 24.0 25.4 16.3 17.1
2,000 138 146 23.5 24.9 15.9 16.6
3,000 133 141 22.6 24.0 15.1 15.7
4,000 128 136 21.8 23.2 14.3 14.9
5,000 123 131 21.0 22.3 13.6 14.1
6,000 120 128 20.4 21.8 13.2 13.7
8,000 113 121 19.2 20.6 12.3 12.7
10,000 108 116 18.4 19.8 11.6 12.1
12,000 103 111 17.5 18.9 11.0 11.4
14,000 98 106 16.7 18.1 10.4 10.7
Gasoline = 5.87 lbs per gallon @ 70 F.
160

Fuel - 100/100LL
Full Rich, 2700 RPM
Fuel Temp 70°
150

140

130
Fuel Flow (PPH)

120

110

100

90
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Pressure Altitude (X1000 ft)

Figure 7-4. IO-550-A Altitude Leaning Schedule

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 Engine Operation
Table 7-7. IO-550-B Engine Altitude Leaning Schedule
Full Throttle RPM, Full Rich Mixture 300 BHP @ 2700 RPM
Fuel Flow Fuel Flow Metered Fuel
Pressure Altitude (lbs/hr) (gals/hr) Pressure PSID
(Set Altimeter at 29.92 in. Hg.) Min. Max. Min. Max. Min. Max.
Sea Level 146 156 24.9 26.6 17.2 18.3
1,000 145.5 155.5 24.8 26.5 17.1 18.2
2,000 145 155 24.7 26.4 17.0 18.1
3,000 144 154 24.5 26.3 16.9 17.9
4,000 142 152 24.2 25.9 16.5 17.5
5,000 139 149 23.7 25.4 16.1 17.0
6,000 135.5 145.5 23.1 24.8 15.5 16.5
8,000 127 137 21.6 23.3 14.2 15.1
10,000 117 127 19.9 21.6 12.8 13.6
12,000 110 120 18.7 20.4 11.9 12.6
14,000 105 115 17.9 19.6 11.3 11.9
Gasoline = 5.87 lbs per gallon @ 70 F.
160

Fuel - 100/100LL
Full Rich, 2700 RPM
Fuel Temp 70°
150

140

130
Fuel Flow (PPH)

120

110

100

90
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Pressure Altitude (X1000 ft)

Figure 7-5. IO-550-B Altitude Leaning Schedule

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Engine Operation
Table 7-8. IO-550-C Engine Altitude Leaning Schedule
Full Throttle RPM, Full Rich Mixture 300 BHP @ 2700 RPM
Fuel Flow Fuel Flow Metered Fuel
Pressure Altitude (lbs/hr) (gals/hr) Pressure PSID
(Set Altimeter at 29.92 in. Hg.) Min. Max. Min. Max. Min. Max.
Sea Level 152 160 25.9 27.2 18.2 18.9
1,000 151 159 25.7 27.1 18.0 18.7
2,000 148 156 25.2 26.6 17.5 18.2
3,000 143 151 24.4 25.7 16.7 17.4
4,000 138 146 23.5 24.9 15.9 16.5
5,000 134 142 22.8 24.2 15.3 15.9
6,000 130 138 22.1 23.5 14.7 15.3
8,000 123 131 21.0 22.3 13.6 14.1
10,000 118 126 20.1 21.5 12.9 13.4
12,000 113 121 19.3 20.6 12.3 12.7
14,000 108 116 18.4 19.8 11.7 12.1
Gasoline = 5.87 lbs per gallon @ 70 F.
170
Fuel - 100/100LL
Full Rich, 2700 RPM
Fuel Temp 70°
160

150

140
Fuel Flow (PPH)

130

120

110

100

90
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Pressure Altitude (X1000 ft)

Figure 7-6. IO-550-C Altitude Leaning Schedule

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 Engine Operation
Table 7-9. IO-550-D, E, F, & L Engine Altitude Leaning Schedule
Full Throttle Static RPM, Full Rich Mixture 300 BHP @ 2700 RPM
Fuel Flow Fuel Flow Metered Fuel
Pressure Altitude (lbs/hr) (gals/hr) Pressure PSID
(Set Altimeter at 29.92 in. Hg.) Min. Max. Min. Max. Min. Max.
Sea Level 143 155 24.4 26.4 17.2 20.0
1,000 142.5 154.5 24.3 26.3 17.1 19.9
2,000 142 154 24.2 26.2 17.0 19.8
3,000 141 153 24.0 26.1 16.9 19.6
4,000 139 151 23.7 25.7 16.5 19.2
5,000 136 148 23.2 25.2 16.0 18.7
6,000 133 145 22.6 24.7 15.5 18.2
8,000 124 136 21.1 23.2 14.0 16.6
10,000 114 126 19.4 21.5 12.5 15.0
12,000 107 119 18.2 20.3 11.5 13.9
14,000 102 114 17.4 19.4 10.8 13.1
Gasoline = 5.87 lbs per gallon @ 70 F.
160
Fuel - 100/100LL
Full Rich, 2700 RPM
Fuel Temp 70°
150

140

130
Fuel Flow (PPH)

120

110

100

90
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14
Pressure Altitude (X1000 ft)

Figure 7-7. IO-55-D, E, F & L Altitude Leaning Schedule

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Engine Operation
7-3. Normal Operation
Information in this section supplements instructions for normal ground operation found in
the AFM/POH. Adhere to the aircraft AFM/POH operating procedures.
WARNING
Before flying the aircraft, ensure all “Flight Prerequisites” in
Section 7-2 have been completed, in addition to the aircraft
manufacturer's instructions found in the AFM/POH.
Operation of a malfunctioning engine can result in additional
damage to the engine, bodily injury or death.
Supplemental instructions for normal operation in this section are:
• Pre-operational Requirements
• Engine Start
• Engine Ground Run-up
• Engine Shutdown
7-3.1. Pre-operational Requirements
1. Check the oil level, and verify quantity is within specified limits.
2. Verify oil fill cap and dipstick are secure.
3. Drain all fuel sumps and strainers in accordance with aircraft manufacturer’s
recommendations.
4. Check the fuel system according to the Pilot’s Operating Handbook (POH) and
verify compliance with Section 7-2.2, “Engine Fuel Requirements.”
5. Check propeller and propeller hub for cracks, oil leaks, and security.
6. Check engine nacelle for signs of damage, leaks, and debris.
7. Check the throttle, mixture control, propeller (if equipped), carburetor heat (if
equipped) and alternate air supply controls for freedom of movement and full range
of travel.

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 Engine Operation
7-3.2. Engine Start
WARNING
Do not attempt to start an engine with an over-primed or
flooded induction system. Starting an engine with a flooded
induction system can result in hydraulic lock and subsequent
engine malfunction or failure. Allow excess fuel to drain from
the intake manifold and/or cylinder prior to attempting to start
the engine.
Refer to the aircraft POH for detailed engine starting procedures. Complete Section 7-3.1,
“Pre-operational Requirements” prior to engine start. Be familiar with the quantity and
location of the engine fuel system drains.
CAUTION: Attempting to start an engine with a partially discharged
aircraft battery may result in damage to the starter relay or possible
engine kick-back resulting in a broken starter adapter clutch spring
and/or subsequent engine damage.
When starting the engine, ensure the battery is completely charged, especially in sub-
freezing temperatures.
Verify the tasks listed in Table 7-2, “Flight Prerequisites,” have been completed in
addition to those required by the aircraft POH, aircraft manufacturer, or Supplemental
Type Certificate (STC) holder. Note the following:
• If the engine is being started in extreme cold, preheating may be required. Refer to
Section 7-4.1, “Engine Operation in Extreme Cold.”
• If the engine is started in hot weather, refer to the AFM/POH
• If the engine is being started at high altitude, refer to the AFM/POH
WARNING
Ensure the propeller arc is clear of personnel and obstructions
before starting the engine.
CAUTION: Release the starter as soon as the engine fires. Never
engage the starter while the propeller is turning. 

Engine operation without oil pressure will result in engine
malfunction and probable failure.
NOTE: Check oil pressure frequently. Oil pressure indication must be
noted within 30 seconds in normal weather. If no oil pressure is observed,
stop the engine and investigate the cause.
1. Propeller ........................................................... Clear
2. Master Switch .................................................. ON
3. Ignition Switch................................................. BOTH
4. Mixture Control ............................................... FULL RICH
5. Propeller Control.............................................. High RPM

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Engine Operation
6. Boost Pump (if equipped) ................................ According to AFM/POH
7. Throttle............................................................. ¼ Open
8. Primer (if equipped)......................................... ON (refer to AFM/POH 
for priming time)
CAUTION: Release starter switch as soon as engine fires. Never
engage the starter while the propeller is still turning. 

EZR Do not energize the starter for longer than 30 seconds. If the
engine does not start after cranking for 30 seconds, release the
starter switch and allow the starter motor to cool for 3-5 minutes
before another starting attempt.

SKY Do not engage the starter for longer than 10 seconds. Allow
20 seconds for the starter to cool after each engagement. If engine
start is unsuccessful after six attempts, release the starter switch and
allow the starter motor to cool for 30 minutes before another starting
attempt is made.

9. Ignition Switch................................................. Start, then RELEASE

10. Throttle............................................................. According to AFM/POH
11. Primer (if equipped)......................................... OFF (refer to AFM/POH 
for priming time)
12. Oil Pressure...................................................... Check
RESULT: Must have oil pressure indication within 30 seconds.
7-3.2.1. Cold Start
Follow the AFM/POH instructions, using the same procedure as for a normal start. After
the engine begins running, it may be necessary to operate the boost pump intermittently to
prevent the engine from stalling.
7-3.2.2. Flooded Engine
WARNING
Do not operate the engine if hydraulic lock is suspected. Engine
damage may occur. Perform a “Hydraulic Lock Inspection”
according to instructions in Section 6-5.2. If no fuel drainage is
observed, discontinue starting attempts until the cause is
determined. Inspect the cylinder drains for obstructions.
Excessive priming may cause fuel to accumulate in the induction system or cylinder faster
than cylinder drains can evacuate it. If hydraulic lock is suspected, discontinue starting
attempts until proper drain operation is verified.

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 Engine Operation
7-3.2.3. Hot Start
For engines with Continental continuous flow fuel injection systems, supplement the
AFM/POH normal starting instructions with the following:
NOTE: For several minutes after stopping a hot engine, heat soaked fuel
injection components, (especially the fuel pump) may cause fuel
vaporization resulting in restarting difficulties. To reduce difficulty,
perform the following steps:
1. Fuel Selector Valve ......................................... ON
2. Throttle............................................................. CLOSED
CAUTION: In the IDLE CUT-OFF position, the fuel manifold valve
positively stops fuel flow to the fuel injectors if inlet fuel pressure is
less than 1.0 psi. If the boost/prime pump is enabled with the mixture
control in IDLE CUT-OFF and the pressure is above the fuel
manifold valve nominal shutoff pressure, fuel will be forced past the
fuel manifold valve, through the injectors and into the cylinders.
Extended operation in this condition is not recommended. Excessive
fuel in the cylinders’ intake port will vent overboard through the
cylinder drains and collect below the aircraft. Refer to AFM/POH
for boost pump operational limits.
3. Mixture Control ............................................... IDLE CUT-OFF
4. Boost Pump (if equipped) ................................ According to AFM/POH
5. Allow fuel to drain from induction/cylinder drains prior to engine start; follow
AFM/POH starting instructions.

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Engine Operation
7-3.3. Ground Run-up
CAUTION: DO NOT operate the engine at run-up speeds unless the
oil temperature in turbocharged engines is at least 100°F (38°C)
(75°F (24°C) for naturally aspirated engines) and the oil pressure is
within the 30-60 psi range. Refer to engine Maintenance and
Overhaul manual for operating parameter exceptions where
applicable. Operating the engine above idle before reaching
minimum oil temperature may cause a loss of oil pressure and
engine damage.
1. Maneuver aircraft nose into wind
2. Throttle............................................................. IDLE
CAUTION: Avoid prolonged idle at low RPM to prevent spark plug
fouling.
3. Propeller Control (if equipped)........................ FULL INCREASE
4. Mixture............................................................. FULL RICH
5. Throttle............................................................. 900-1000 RPM
6. Maintain engine RPM between 900 and 1000 RPM for at least one minute or until
engine oil temperature reaches minimum takeoff temperature (minimum takeoff
temperature is 100°F (38°C) for turbocharged engines or 75°F (24°C) for naturally
aspirated engines).
WARNING
Absence of RPM drop during the magneto check may be an
indication of a faulty ignition circuit resulting in a condition
known as “Hot Magneto.” Should the propeller be turned by
hand, the engine may inadvertently start and cause personal
injury or death. This condition must be corrected prior to
continued aircraft operation.
CAUTION: When operating on single ignition, some RPM drop and
slight engine roughness as each magneto is switched off should be
noted. Excessive (greater than 150 RPM) RPM drop may indicate a
faulty magneto or fouled spark plugs.
NOTE: If the engine runs roughly after single magneto operation, increase
engine speed to 2200 RPM in the BOTH position and lean the mixture
control until the RPM peaks for ten seconds before returning to the FULL
RICH position to clear the spark plugs and smooth operation before returning
to single magneto operation.
Limit ground operation to time necessary to complete engine warm-up and pre-flight
checkout.
7. Throttle............................................................. 1700 RPM
a. Magneto Checkout
1) Ignition Switch..........................................R
RESULT: RPM drops 150 RPM or less; record Left Magneto channel drop
results. Maximum allowable RPM drop spread between magneto channels is 50
RPM.

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 Engine Operation
2) Ignition Switch ...................................... BOTH
RESULT: Engine RPM returns to approximately 1700 RPM. Allow ignition
switch to remain in BOTH for approximately 30 seconds to clear engine.
3) Ignition Switch..........................................L
RESULT: RPM drops 150 RPM or less; record Right Magneto channel drop
results. Maximum allowable RPM drop spread between magneto channels is 50
RPM.
4) Ignition Switch ...................................... BOTH
RESULT: Engine RPM returns to approximately 1700 RPM. . Return the
engine to operation with both mags
b. Propeller Governor Checkout (if equipped)
1) Throttle.................................................. According to AFM/POH
2) Propeller Control................................... Low RPM position
RESULT: Engine RPM decreases to minimum governing speed or as
specified by aircraft manufacturer.
3) Propeller Control................................... High RPM position
4) Cycle the Propeller Governor control 2-3 times to cycle warm oil through the
propeller hub.
If equipped:
5) Propeller GovernorFeather
RESULT: RPM drops below minimum governing speed.
6) Propeller Governor................................ Full Increase
RESULT: Engine RPM return to RPM before Propeller Feather check.

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Engine Operation
7-3.4. Engine Shutdown
Supplement the AFM/POH engine shutdown procedures with the following:
1. Boost Pump (if equipped) ................................ OFF
2. Throttle............................................................. 1700 RPM
WARNING
Absence of RPM drop during the magneto check may be an
indication of a faulty ignition circuit resulting in a condition
known as “Hot Magneto.” Should the propeller be turned by
hand, the engine may inadvertently start and cause personal
injury or death. This condition must be corrected prior to
continued aircraft operation.
CAUTION: When operating on single ignition, some RPM drop
should be noted. Normal indications are up to 150 RPM drop and
slight engine roughness as each magneto is switched off. RPM drop
in excess of 150 RPM may indicate a faulty magneto or fouled spark
plugs. Avoid prolonged single magneto operation to preclude spark
plug fouling.
NOTE: If the engine runs roughly after single magneto operation,
increase engine speed to 2200 RPM in the BOTH position and lean the
mixture control until the RPM peaks for ten seconds before returning to
the full rich position to clear the spark plugs and restore smooth operation
before returning to single magneto operation.
3. Ignition Switch................................................. R
RESULT: RPM drops 150 RPM or less; record Left Magneto channel drop results.
Maximum allowable RPM drop spread between magneto channels is 50 RPM.
4. Ignition Switch................................................. BOTH
RESULT: Engine RPM returns to approximately 1700 RPM.
5. Ignition Switch................................................. L
RESULT: RPM drops 150 RPM or less; record Right Magneto channel drop results.
Maximum allowable RPM drop spread between magneto channels is 50 RPM.
CAUTION: Turbochargers require a cooling/spin down period
before engine shutdown. Failure to allow the turbocharger to cool/
spin down will shorten turbocharger service life. Supplement the
AFM/POH aircraft shutdown procedures with these instructions:
6. Ignition Switch................................................. BOTH
RESULT: Engine RPM returns to approximately 1700 RPM.
7. Throttle.............................................................IDLE
RESULT: For turbocharged engines only, allow engine to run for five minutes below
900 RPM to allow turbochargers to slow to a lower RPM and cool down. For all
other, proceed to next step.
8. Mixture Control ............................................... IDLE CUT-OFF
9. Ignition Switch................................................. OFF
10. Fuel Selector .................................................... OFF (according to AFM/POH)

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 Engine Operation
7-4. Engine Operation in Abnormal Environments
The anticipated types of abnormal environments are:
• Extreme cold weather (Reference AFM/POH and Section 7-4.1)
• Extreme hot weather (Reference AFM/POH)
• High density altitude ground operation (Reference AFM/POH)
7-4.1. Engine Operation in Extreme Cold
Engine starting is more difficult in extremely cold weather. Cold soaking causes the oil to
thicken (more viscous) and clearances are reduced due to the lower temperature. These
factors increase engine friction, reduce engine cranking rpm and increase the starter
cranking amperage from the battery. At low temperatures, aviation gasoline does not
vaporize readily, further complicating the starting procedure.
WARNING
Over priming can cause a flooded intake resulting in a
“hydraulic lock” event and subsequent engine malfunction or
failure. If you over-prime (flood) the engine, ensure excess fuel
has drained from the intake manifold and/or cylinder prior to
attempting engine start.
CAUTION: Use an external power source when attempting to start
aircraft engine in cold weather. Attempting to start an engine with a
partially discharged aircraft battery may result in damage to the
starter relay or possible engine kick-back resulting in a broken
starter adapter clutch spring and/or subsequent engine damage.
False starting (failure to continue running after starting) often results in condensation on
spark plug electrodes. This moisture can freeze and must be eliminated either by
preheating the engine or removing and cleaning the spark plugs.
Engine preheating and an auxiliary power unit (APU) are required to facilitate engine
starting when the engine has been exposed to temperatures below 20ºF (-7°C) for more
than two hours. Refer to Section 7-4.1.1 and the AFM/POH for specific instructions. At
ambient temperatures between 20º and 40ºF (-7º and 4ºC), refer to Section 7-4.1.1.3.
WARNING
Failure to properly preheat a cold-soaked engine may result in
oil congealing within the engine, oil hoses, and oil cooler with
subsequent loss of oil flow, possible damage to the engine, and
subsequent engine failure.
Superficial application of preheat to a cold soaked engine can
cause damage to the engine. An inadequate application of
preheat may warm the engine enough to permit starting but
will not decongeal oil in the sump, lines, cooler, filter, etc.
Congealed oil in these areas require considerable preheat. The
engine may start and appear to run satisfactorily, but can be
damaged from lack of lubrication due to the congealed oil

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Engine Operation
clogging engine oil passages. The amount of damage will vary
and may not become evident for many hours. However, the
engine may be severely damaged and may fail shortly after
application of high power.
Prior to operation and/or storage in cold weather, ensure the engine is serviced with the
correct viscosity oil for the ambient air temperature.
In the event of temporary cold weather operation, store the aircraft in a heated hangar
between flights. Service the oil sump as required with the specified oil grade according to
the “Engine Oil Servicing” instructions in Section 6-4.8.
7-4.1.1. Engine Preheating
CAUTION: Proper engine preheating procedures require thorough
application of preheat to all parts of the engine. Apply hot air
directly to the oil sump and external oil lines as well as the cylinders,
air intake, and oil cooler. Excessively hot air can damage non-
metallic components such as seals, hoses, and drive belts; do not
attempt to hasten the preheat process.
The preferred method of preheating is to place the aircraft in a heated hangar for a
minimum of four hours prior to flight. Optional preheating methods are:
• A high volume combustion heater with ducts directed to the engine oil sump,
cylinders, and oil cooler; refer to Section 7-4.1.1.1.
Or
• An engine mounted preheating system; refer to Section 7-4.1.1.2.

7-4.1.1.1. Engine Preheat with a Combustion Heater

If a heated hangar is not available and the aircraft and engine have been exposed to
temperatures below 20ºF (-7ºC) for two hours or more, without an engine mounted
preheating system, use the following method:
1. Select a high-volume air heater.
NOTE: Small electric heaters inserted in the cowling opening do not
appreciably warm the oil and may result in superficial preheating.
2. Preheat all engine parts. Apply preheated air directly to the listed parts for at least 30
minutes:
a. Oil sump
b. Oil filter
c. External oil lines
d. Oil cooler
e. Cylinder assemblies
f. Air intake

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 Engine Operation
3. Periodically feel the top of the engine for warmth. Apply heat directly to the
induction tubes and cylinders will promote vaporization and ease starting.
Alternately heat the sump and engine cylinders until engine start.
4. Start the engine immediately after completion of the preheating process. Since the
engine will be warm, follow the normal start instructions in Section 7-3.2.
CAUTION: If oil pressure is not indicated within 30 seconds, shut
down the engine and determine the cause. Operating the engine
without oil pressure may result in engine damage. Do not close the
cowl flaps in an attempt to hasten engine warm-up.
5. Operate the engine at 1000 RPM until some oil temperature is indicated.
a. Monitor the oil pressure closely. If necessary, retard the throttle to maintain oil
pressure below 100 psi. If oil pressure is less than 30 psi, or cannot be maintained
below 100 psi, shut the engine down and repeat the preheat process. Do not close
the cowl flaps to facilitate engine warm-up.
b. Monitor the oil temperature until it reaches minimum takeoff oil temperature
(minimum takeoff temperature is 100°F (38°C) for turbocharged engines or 75°F
(24°C) for naturally aspirated engines).
CAUTION: Do not operate the engine at speeds above 1700 RPM
unless the oil temperature reaches minimum takeoff oil temperature
and indicated oil pressure is between 30 and 60 psi. Refer to engine
Maintenance and Overhaul manual for operating parameter
exceptions where applicable
6. Run the engine up to 1700 RPM; in 100 RPM increments to prevent oil pressure
from exceeding 100 psi.
WARNING
Operating the engine above 1700 RPM before reaching the
minimum oil temperature may result in engine malfunction,
engine failure, injury or death.
7. At 1700 RPM, adjust the propeller control to LOW RPM (if equipped) until
minimum governing RPM is observed; return the control to HIGH RPM. Repeat this
procedure three or four times to circulate warm oil into the propeller dome.
8. If the aircraft manufacturer recommends checking the propeller feathering system,
move the control to the FEATHER position. Do not allow the RPM to drop more
than 300 RPM below minimum governing speed.
CAUTION: Continually monitor oil pressure during run up.
9. When oil temperature has reached minimum takeoff oil temperature and oil pressure
does not exceed 60 psi at 2500 RPM, the engine has been warmed sufficiently to
accept full rated power.

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Engine Operation
7-4.1.1.2. Engine Preheat with an Engine-Mounted Preheater
WARNING
Do not leave an engine-mounted pre-heater system on for more
than 24 hours prior to flight. Continuous operation of engine-
mounted preheater systems may result in aggressive internal
engine corrosion.
If a heated hangar is not available and the aircraft and engine have been exposed to
temperatures below 20ºF (-7ºC) for two hours or more and has an engine-mounted
preheating system the following procedure may be used.
Engine mounted preheating systems should include individual cylinder head heater
thermocouples, oil sump heater pad and crankcase heater pad. The use of a nacelle blanket
will increase the effectiveness of engine preheating.
1. Follow the preheating system's manufacturer's installation and operation
instructions.
2. Begin preheating of the engine at least five hours prior to expected departure. Do not
operate an engine preheating system continuously for more than 24 hours.
NOTE: The use of an approved thermal blanket or cover will help reduce
the effects of wind and cold air circulation when the aircraft is not stored
in a hangar. The preheating system manufacturer should have thermal
blankets available.
3. Start the engine immediately after completion of the preheating process using the
normal start procedure in Section 7-3.2.
CAUTION: If oil pressure is not indicated within 30 seconds, shut
down the engine and determine the cause. Operating the engine
without oil pressure may result in engine damage. Do not close the
cowl flaps in an attempt to hasten engine warm-up.
4. Operate the engine at 1000 RPM until some oil temperature is indicated.
a. Monitor the oil pressure closely. If necessary, retard the throttle to maintain oil
pressure below 100 psi. If oil pressure is less than 30 psi, or cannot be maintained
below 100 psi, shut the engine down and repeat the preheat process. Do not close
the cowl flaps to facilitate engine warm-up.
b. Monitor the oil temperature until it reaches at minimum takeoff oil temperature
(minimum takeoff temperature is 100°F (38°C) for turbocharged engines or 75°F
(24°C) for naturally aspirated engines).
CAUTION: Do not operate the engine at speeds above 1700 RPM
unless the oil temperature reaches minimum takeoff oil temperature
and the oil pressure is between 30 to 60 psi.
5. Run the engine up to 1700 RPM; approach this RPM in increments to prevent oil
pressure from exceeding 100 psi.

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15 Sep 2019
 Engine Operation
WARNING
Operating the engine above 1700 RPM before reaching the
minimum takeoff oil temperature may result in engine
malfunction, engine failure, injury or death.
6. At 1700 RPM, adjust the propeller control (if equipped) to LOW RPM until
minimum governing RPM is observed; return the control to HIGH RPM. Repeat this
procedure three or four times to circulate warm oil into the propeller dome.
7. If the aircraft manufacturer recommends checking the propeller feathering system,
move the control to the FEATHER position but do not allow the RPM to drop more
than 300 RPM below minimum governing speed.
CAUTION: Continually monitor oil pressure during run up.
8. When oil temperature has reached minimum takeoff oil temperature and oil pressure
does not exceed 60 psi at 2500 RPM, the engine has been warmed sufficiently to
accept full rated power.
7-4.1.1.3. Cold Weather Starting Without Preheating
At ambient temperature between 20° to 40ºF (-7°to 4°C), perform the following:
CAUTION: Attempting to start your engine with a partially
discharged aircraft battery may result in damage to the starter relay
or possible engine kickback, resulting in a broken starter adapter
clutch spring and/or subsequent internal engine damage.
1. Use an external power source or ensure the aircraft battery is fully charged.
2. Use the normal start procedure in Section 7-3.2 and the aircraft AFM/POH. Do not
overprime the engine.
WARNING
Overpriming can cause a flooded intake resulting in a
“hydraulic lock” event and subsequent engine malfunction or
failure. If you over prime, or flood your engine, ensure excess
fuel has drained from the intake manifold and/or cylinder prior
to attempting engine starting.
CAUTION: If oil pressure is not indicated within 30 seconds, shut
down the engine and determine the cause. Operating the engine
without oil pressure may result in engine damage. Do not close the
cowl flaps in an attempt to hasten engine warm-up.
3. Operate the engine at 1000 RPM until some oil temperature is indicated.
4. Monitor the oil pressure closely. If necessary, retard the throttle to maintain oil
pressure below 100 psi. If oil pressure is less than 30 psi, or cannot be maintained
below 100 psi, shut the engine down and follow the preheat instructions to prevent
engine damage.

Standard Practice Maintenance Manual 7-29

15 Sep 2019
Engine Operation
5. Monitor the oil temperature until it reaches at minimum takeoff oil temperature
(minimum takeoff temperature is 100°F (38°C) for turbocharged engines or 75°F
(24°C) for naturally aspirated engines).
CAUTION: In the next step, do not operate the engine at speeds
above 1700 RPM unless the oil temperature reaches minimum rated
takeoff temperature and the oil pressure is between 30 to 60 psig.
Refer to engine Maintenance and Overhaul manual for operating
parameter exceptions where applicable.
6. Run the engine up to 1700 RPM; approach this RPM in increments to prevent oil
pressure from exceeding 100 psi.
WARNING
Operating the engine above 1700 RPM before reaching the
minimum oil temperature may result in engine malfunction,
engine failure, injury or death.
7. At 1700 RPM, adjust the propeller control (if equipped) to LOW RPM until
minimum governing RPM is observed; return the control to HIGH RPM. Repeat this
procedure three or four times to circulate warm oil into the propeller dome.
8. If the aircraft manufacturer recommends checking the propeller feathering system,
move the control to the FEATHER position but do not allow the RPM to drop more
than 300 RPM below minimum governing speed.
CAUTION: Continually monitor oil pressure during run up.
9. When oil temperature has reached minimum takeoff oil temperature and oil pressure
does not exceed 60 psi at 2500 RPM, the engine has been warmed sufficiently to
accept full rated power.

7-30 Standard Practice Maintenance Manual

15 Sep 2019
 Troubleshooting
Chapter 8. Troubleshooting

Fault isolation paths within this chapter indicate the most likely causes of given
symptom(s) and corrective action(s). The fault isolation paths and repair procedures are
developed from log book entries and best known practices. New symptoms, fault isolation
methods, and corrective actions may be added in the future, when warranted.
NOTE: Fault isolation paths provided are for Continental engines
equipped with a carburetor or continuous flow fuel injection system. For
engines equipped with FADEC or servo controlled fuel injection systems,
refer to the primary ICA (reference Section 1-1.1).
WARNING
Any attempt by unqualified personnel to adjust, repair, or
replace any parts may result in engine malfunction or failure.
Continued operation of a malfunctioning engine can cause
further damage to a disabled component and possible injury to
personnel. Do not return an engine to service unless it functions
according to specifications.

Standard Practice Maintenance Manual 8-1

15 Sep 2019
Troubleshooting
8-1. General Troubleshooting
Troubleshooting procedures vary for engines with carburetors versus fuel injected
engines. Refer to Section 8-1.2 for fuel injected engines and Section 8-1.1 for engines
with carburetors.
8-1.1. General Troubleshooting for Engines equipped with a Carburetor

Engine Will Not Start

Check switch positions:

Starter Master Power Switch……………….....ON
NOT
turns when ignition switch OK
Fuel Selector Valve…………...……….ON
is engaged? Throttle………………..………….¼ OPEN
Ignition Switch...………….…..….…BOTH

OK

Switches NOT Reposition switches and

Go to positioned properly? OK retry
Section 8-5

OK

Service or replace battery

Check battery condition NOT according to Airframe
OK Manufacturer’s
instructions.
OK

Check Ignition Switch

wiring according to Repair wiring according to
NOT
Airframe Manufacturer’s
Airframe Manufacturer’s OK
instructions.
instructions.
OK

Service with fuel approved

NOT
Check Fuel Level in tank(s) OK
for engine model
(Section 7)
OK

Go to
Section
8-1.4

8-2 Standard Practice Maintenance Manual

15 Sep 2019
 Troubleshooting
8-1.2. General Troubleshooting for Engines with Continental Continuous Flow
Fuel Injection Systems

Engine Will Not Start

Master Power Switch……………….....ON

Fuel Selector Valve…………...……….ON
Mixture Control……….……....FULL RICH NOT Reposition switches and
Throttle………………..………….¼ OPEN OK retry
Boost Pump………………………per POH
Ignition Switch...………….…..….…BOTH
OK

Service or replace battery

Starter turns when ignition NOT NOT according to Airframe
Check battery condition
switch is engaged? OK OK Manufacturer’s
instructions.
OK OK

Engine turns with starter? NOT Check Ignition Switch

OK wiring according to Repair wiring according to
NOT
Airframe Manufacturer’s
Airframe Manufacturer’s OK
instructions.
OK Replace starter instructions.
adapter OK

Check fuel level in tanks NOT Replace starter

OK

Service with
OK appropriate fuel
grade.

NOT
Check fuel pressure OK

Check for fuel line

OK obstruction
NOT
Check fuel flow OK
Refer to Ignition
OK Troubleshooting (Sect. 8-3)

Refer to Ignition
Troubleshooting (Sect. 8-7)

Standard Practice Maintenance Manual 8-3

15 Sep 2019
Troubleshooting
8-1.3. Engine Runs Rough
Engine troubleshooting techniques vary depending on the engine fuel system. For engines
equipped with a carburetor refer to Section 8-1.3.1. To troubleshoot rough running engines
equipped with continuous flow fuel injection systems, refer to Section 8-1.3.1.
8-1.3.1. Engine Runs Rough (equipped with Carburetor)

Engine Runs

Check induction air NOT Replace induction

Roughly AT IDLE Increase IDLE speed OK
filter (airframe) OK air filter

AT ANY OK
SPEED

Check for induction system NOT Correct according to Airframe

obstruction OK Manufacturer’s instructions Go to
Section 8-6
OK

NOT Correct according to Propeller

Check propeller for imbalance OK Manufacturer’s instructions
OK

Check/adjust carburetor IDLE NOT Adjust according to

mixture adjustment. OK instructions in primary ICA
OK

Check carburetor/priming system NOT

Correct leak
for leaks OK

OK

Check for loose or broken engine

NOT
mounts according to Airframe OK Replace engine mounts
Manufacturer’s instructions.
OK

Possible hydraulic lifter

malfunction or burned or warped
exhaust valves or valve seats.
Perform Cylinder Differential
Pressure Test and Borescope
Inspection (Section 6).

8-4 Standard Practice Maintenance Manual

15 Sep 2019
 Troubleshooting
8-1.3.2. Engine Runs Rough (equipped with Continental Continuous Flow Fuel
Injection System)

Engine Runs Rough at IDLE

Check air filter for cleanliness NOT Replace air filter according to the
(see Aircraft Manufacturer’s OK Aircraft Maintenance Manual.
maintenance instructions).
OK

Perform Induction System Torque loose fasteners to

NOT
Inspection; look for induction OK Appendix B specifications.
system leaks.

OK
Go to
Perform Ignition System NOT Section
Inspection (Section 6). OK 8-6.1

OK

Perform Engine Operational Adjust fuel pressure to meet

NOT
Check (Section 6). OK
engine specifications
(Section 6).

OK

Possible hydraulic lifter

malfunction or burned or warped
exhaust valves or valve seats.
Perform Cylinder Differential
Pressure Test and Borescope
Inspection (Section 6).

Engine Runs Rough at High

Speed

Check engine mount legs for Replace engine mount legs on

NOT
cracks; check mount leg fastener OK
condition. Torque fasteners to
torque. Appendix B specifications.
OK
Go to
Perform Ignition System NOT OK
Section
Inspection (Section 6). 8-6.1
OK

Check propeller for imbalance. NOT Correct according to propeller

OK manufacturer’s instructions

Standard Practice Maintenance Manual 8-5

15 Sep 2019
Troubleshooting
8-1.4. Engine Will Not Run

Engine will not run at IDLE

Verify aircraft fuel selector is set

to fullest tank.
OK

Fuel System? Carburetor

Cont. Flow
Fuel Injection
Perform Engine
NOT Turn aircraft boost NOT Operational Check and
Check Fuel Pressure. OK pump ON OK adjust fuel pressure as
required (Section 6).
NOT
OK
OK
Replace Engine Driven
Fuel Pump
Correct according
Check for induction system leaks NOT to airframe NOT Check for induction system
or obstructions. OK manufacturer’s OK leaks or obstructions.
instructions
OK
OK NOT
OK
Check idle mixture and
priming system for leaks
Probable worn or fouled spark
plugs. Perform Ignition System OK

Inspection (Section 6). Go to Possible carburetor

Section malfunction. Replace with
8-6.1. serviceable carburetor or
repair replace faulty
components

8-6 Standard Practice Maintenance Manual

15 Sep 2019
 Troubleshooting

Engine Starts, Runs Briefly,

then Stops

Verify aircraft fuel selector is set

to fullest tank.

OK

Check Fuel Tank ventilation Clear the fuel tank vent line
NOT
according to the Aircraft OK according to Aircraft Maintenance
Maintenance Manual. Manual.
OK

Check aircraft fuel strainer

NOT Clean the fuel strainer according to
according to the Aircraft OK Aircraft Maintenance Manual.
Maintenance Manual.
OK

Collect fuel sample from tank. NOT Perform Contaminated Fuel System
Inspect for contamination. OK Inspection (Section 6).

OK

Replace engine driven fuel pump

(if equipped)

8-1.5. Engine Indication Malfunctions

Abnormal Engine Indications

Go to
NOT Section
Abnormal fuel system indication. OK 8-3

OK

Go to
Abnormal lubrication system NOT Section
indication. OK 8-7

Standard Practice Maintenance Manual 8-7

15 Sep 2019
Troubleshooting
8-1.6. Engine Performance Malfunctions
Engine Runs Rich at Cruise Power ..........................................................see Section 8-3
Engine Misses at High Speed ..................................................................see Section 8-8

Poor Engine Performance

Go to
Inspect Induction System NOT Section
(Section 6). OK 8-2
OK

NOT Correct according to Airframe

Check throttle rigging OK Manufacturer’s instructions
OK

Check spark plug condition NOT Replace spark plugs

(Section 6). OK (Section 6).
OK

Cont. Flow
Carburetor Fuel System?
Fuel Injection

Check IDLE Mixture

adjustment and/or Perform Engine
accelerator pump Operational Check
operation, and/or priming (see Section 6).
system for leaks
OK NOT
NOT OK OK

Replace with serviceable

carburetor or repair/adjust NOT OK
faulty components.
Perform Cylinder
NOT Go to
Differential Pressure OK Section
Check (Section 6).
8-3
OK

Go to Repair according to
Section Section 6
8-10 Instructions.

8-8 Standard Practice Maintenance Manual

15 Sep 2019
 Troubleshooting

Sluggish Engine Operation/Low

Power

Adjust Control Rigging

Check Engine Control Rigging NOT
according to Airframe
(Section 6) OK
Manufacturer’s Instructions
OK

Perform Engine Operational Go to

Check (Section 6). NOT Section
For carbureted engines, refer to OK 8-3
the primary ICA.
OK
Go to
Perform Induction System NOT Section
Inspection (Section 6) OK 8-2

OK
Go to
Inspect Turbocharger and NOT Section
Exhaust System (Section 6) OK 8-10

8-2. Induction System

Engine Will Not Start............................................................................. see Section 8-2.1
Engine Will Not Run.............................................................................. see Section 8-2.2
Engine Lacks Power/Low Manifold Air Pressure .................................. see Section 8-2.3
Low Manifold Air Pressure/Loss of Aircraft Critical Altitude .................. see Section 8-2.4

8-2.1. Engine Will Not Start

Engine Will Not Start

Inspect induction system for NOT Remove obstruction according to Airframe

airflow obstructions. OK Manufacturer’s instructions.
OK

Check induction system for loose NOT Torque connections to Appendix B

connections (Section 6). OK specifications.

Standard Practice Maintenance Manual 8-9

15 Sep 2019
Troubleshooting
8-2.2. Engine Will Not Run

Engine Will Not Run At IDLE

Speed

Inspect induction system for leaks

NOT Torque connections to Appendix B
or loose connections OK specifications.
(Section 6).
OK

Perform an Engine Operational

Check to verify engine operation.

8-2.3. Engine Lacks Power/Manifold Pressure Low (Naturally Aspirated Models)

Engine Lacks Power or

Maximum Manifold Pressure
Reduced
OK
Clean, replace or adjust
Inspect throttle for sticking or NOT
according to Airframe
incorrectly adjusted linkage. OK
Manufacturer’s instructions.
OK

Check for dirty air filter (airframe). Clean or replace filter and/or
If carbureted, check for proper NOT service carburetor heat system
operation and rigging of OK according to Airframe
carburetor heat system Manufacturer’s instructions.
OK

Inspect induction system for leaks

NOT Torque connections to
or loose connections OK Appendix B specifications.
(Section 6).

8-10 Standard Practice Maintenance Manual

15 Sep 2019
 Troubleshooting
8-2.4. Engine Lacks Power/Manifold Pressure Low (Turbocharged Models)

Manifold Pressure Low Or

Fluctuating Cannot Reach
Critical Altitude

Clean, replace or adjust

Inspect throttle for sticking or NOT
according to Airframe
incorrectly adjusted linkage. OK
Manufacturer’s instructions.
OK

Clean or replace filter

NOT
Check for dirty air filter (airframe). OK according to Airframe
Manufacturer’s instructions.
OK

Inspect induction system for leaks

NOT Torque connections to
or loose connections OK Appendix B specifications.
(Section 6).
OK

Go to
Section
8-10

Standard Practice Maintenance Manual 8-11

15 Sep 2019
Troubleshooting
8-3. Continental Continuous Flow Fuel Injection System
Engine Will Not Start .............................................................................see Section 8-3.1
Fluctuating or Erroneous Fuel Flow.......................................................see Section 8-3.2
Poor Acceleration ..................................................................................see Section 8-3.3
Fuel Injector Operational Check ............................................................see Section 8-3.4
8-3.1. Engine Will Not Start

Engine will not Start

Turn off aircraft power and check

Fuel Flow OK? YES
ground below system drains.

NO

Check fuel level in tank. NOT Excess

Engine flooded. Clear
Fuel Selector Valve = ON OK fuel present below YES
excess fuel and retry.
system drains?
OK Correct input conditions
and retry. NO

Fuel Disconnect cylinder drain

Pressure NO tubes at check valve .
OK?

Perform Engine Fuel Go to Section

Operational Check present in cylinder NO 8-3.4.
(Section 6). drain tubes?

NOT
OK YES
YES
OK Disconnect airframe drain Clear obstruction,
Replace Engine Driven NOT
line at check valve. Check reconnect fittings and retry
Fuel Pump. OK
drain line for obstruction. Engine Start.
OK

Replace check valve.

Perform Fuel Injection
NOT
System Operational Check OK
(Section 8).

Go to Section
8-6

8-12 Standard Practice Maintenance Manual

15 Sep 2019
 Troubleshooting
8-3.2. Fluctuating or Erroneous Fuel Flow

Fluctuating Or Erroneous Fuel

Flow Indications

Check fuel line routing, heat shield, NOT

Correct fuel line installation.
and fire sleeve installation. OK

NOT Adjust fuel system,

Perform Engine Operation Check OK if necessary.

Check fuel flow gauge and lines Repair or replace fuel flow gauge
NOT
according to Airframe Manufacturer’s OK or lines according to Airframe
instructions. Manufacturer’s instructions.

Repair or replace crew compartment

indicator according to Airframe
Manufacturer’s instructions.

8-3.3. Poor Acceleration

Poor Acceleration

Perform Engine Operational Check

NOT Adjust according to Airframe
(see Chapter 6) to verify fuel system OK Manufacturer’s instructions.
operation.

Check throttle and fuel control linkage

for proper operation.

Perform Ignition Harness and Spark Plug

Diagnostics (see Section 8.6.1).

Standard Practice Maintenance Manual 8-13

15 Sep 2019
Troubleshooting
8-3.4. Fuel Injector Operational Check

Fuel Injector Operational Check

Perform a visual inspection of the

fuel injection system (Section 6).
Perform a Fuel System Inspection
(Section 6).
Correct discrepancies discovered
during inspection.

• Disconnect the fuel line from each fuel

injector assembly. Remove the injector
assemblies from the cylinders
(Section 6).
• Connect the fuel lines to the respective fuel
injector assemblies; torque the fuel lines
(see Appendix B).
• Connect a section of fuel rated clear tubing
to the open end of each injector. Place the
open ends of the tubing in separate
containers (catch cans) to collect the fuel.

Master Power Switch……………....ON

Fuel Selector Valve………………...ON
OK
Boost Pump….……………………...ON
Throttle…………………………...….IDLE
Boost Pump….……………...OFF
Fuel Selector Valve………...OFF
Check fuel supply hoses from fuel tank to
Master Power Switch……....OFF
fuel pump for leaks. Check fuel hoses and NOT
Repair leaking aircraft fuel lines
connections from fuel pump to the fuel OK
according to airframe manufacturer’s
manifold valve for leaks.
instructions. Repair leaking engine fuel
hoses or lines (Section 10).
OK

Throttle……………...Wide Open

Verify fuel flows into the catch

cans with no fuel leaks from the
fuel lines to the fuel injectors.
Repair leaking engine fuel Confirm equal and consistent fuel
YES Leaks detected?
lines or manifold valve flow.
Boost Pump….……………...OFF
Fuel Selector Valve………...OFF
NO Master Power Switch……....OFF

Continued NOTE: Position tuned nozzles will

on next vary flow rates according to the
page jets used. Expect a variance of up
to 30% from one nozzle to
another

8-14 Standard Practice Maintenance Manual

15 Sep 2019
 Troubleshooting

Fuel Injector
Operational Remove fuel injectors from the fuel lines.
Check, cont. Connect clear tubing to the fuel lines and
terminate the tubing in catch cans:

Master Power Switch……....ON

Fuel Selector Valve………...ON
Flow NO Boost Pump….……………...ON
consistent and Throttle……………………….Wide Open
equal Fuel Flow……….……………Check
Boost Pump….……………...OFF
Fuel Selector Valve………...OFF
Master Power Switch……....OFF
Throttle……………………....IDLE/CUTOFF

Flow
consistent and NO
equal

YES

YES

Repair/Replace faulty fuel

Repair faulty fuel injector(s) manifold valve

Assemble, torque and leak check

Perform Fuel System Operational
the Fuel Injection System parts
Check (Section 6).
removed for troubleshooting.

Standard Practice Maintenance Manual 8-15

15 Sep 2019
Troubleshooting
8-4. Charging System
Refer to the aircraft and alternator manufacturer’s applicable charging system
troubleshooting instructions. If troubleshooting indicates the alternator is faulty, remove
and replace the alternator according to the instructions in Section 10-4.
8-5. Starting System

Engine Will Not Start When

Ignition Switch Engaged.

Check Master Power and Ignition Replace starter relay or

Starter motor turns when switch NOT Switch wiring according to NOT repair wiring according to
is engaged? OK Airframe Manufacturer’s OK Airframe Manufacturer’s
instructions. instructions.
OK
OK

Check fuel injection malfunction

Engine turns with starter? OK
(see Section 8-1).
Replace starter.
NOT OK

Replace starter adapter,

if equipped.

Engine Turns Slowly When

Starter Engaged

Replace battery according to

NOT
Check battery condition. OK Airframe Manufacturer’s
instructions.

OK

Replace ignition switch according

Check ignition switch for burned NOT
to Airframe Manufacturer’s
contacts. OK
instructions.
OK

Repair wiring according to

NOT
Check ignition switch wiring. OK Airframe Manufacturer’s
instructions.
OK

Replace starter

8-16 Standard Practice Maintenance Manual

15 Sep 2019
 Troubleshooting
8-6. Ignition System

Engine Will Not Start

NOT Correct wiring according to Airframe

Check for grounded “P”-lead. OK Manufacturer’s instructions.
OK

NOT Replace faulty ignition switch according

Check ignition switch operation. OK to Airframe Manufacturer’s instructions.

OK

Perform Ignition Harness and

Spark Plug Diagnostics
(Section 8-6.1).

Standard Practice Maintenance Manual 8-17

15 Sep 2019
Troubleshooting
8-6.1. Ignition Harness and Spark Plug Diagnostics

Faulty Ignition Harness or

Spark Plug suspected

1. Position Switches:
Master Power Switch………OFF
Fuel Selector Valve………...OFF
Throttle……….………..CLOSED WARNING
Mixture……….….IDLE/CUTOFF Confirm continuity between the
magneto capacitor and aircraft ground
to prevent accidental engine start during
maintenance. Do not stand or place
equipment within the arc of the
2. Remove spark plugs from all propeller.
cylinders.

3. Remove clamps and cable ties

from high voltage harness closest
to cylinder.

4. Connect spark plugs to high

voltage harness so electrodes are
visible.

5. Master Power Switch…..ON

Check ignition lead wires
Ignition Switch....……....START NOT NOT Replace faulty high
with a High Tension Lead
Monitor spark plug electrodes for OK OK voltage leads.
Tester (Section 3).
normal spark as engine turns.
OK

Temporarily connect
serviceable spark plugs to Replace faulty
OK
suspect high voltage leads; spark plugs.
repeat step 5.

NOT
OK

Replace Magneto.

Perform Engine
Operational Check.

8-18 Standard Practice Maintenance Manual

15 Sep 2019
 Troubleshooting
8-7. Lubrication System

Excessive Oil Consumption

Correct source of leak

Visually inspect engine and NOT
(replace seal, tighten
nacelle for evidence of leaks. OK
fittings).
OK

Check engine log book for service

and consumption history. Service Monitor oil consumption
engine oil sump to proper level closely for the next 25 OK No further action required.
with correct grade of aviation hours.
engine oil.
NOT
OK

Perform “Cylinder
Differential Pressure
Check"

High Oil Temperature Indication

Service oil sump to proper

NOT
Check engine oil level. OK level with correct grade of
aviation engine oil.
OK

Check oil pressure relief NOT Replace oil pressure

Check engine oil pressure. LOW
valve operation. OK relief valve.

OK

NORMAL
See Low Oil Pressure
Indication.

Temporarily install a serviceable

Replace oil
oil temperature gauge and OK
temperature gauge.
recheck oil temperature.

NOT
OK

Reinstall original gauge. Check

NOT Replace the engine oil
engine oil temperature control OK temperature control valve.
valve operation.

OK

Inspect the oil cooler

for flow obstruction.

Standard Practice Maintenance Manual 8-19

15 Sep 2019
Troubleshooting

Low Oil Pressure Indication

Service oil sump to proper level

NOT
Check engine oil level. OK
with correct grade of aviation
engine oil.
OK

Change the engine oil and Perform oil analysis.

replace the engine oil filter OK See Section 6 to determine
(Section 6). particulate volume.

NOT
OK

Temporarily install a serviceable

OK Replace oil pressure gauge.
engine oil pressure gauge.

NOT
OK

Temporarily install a serviceable

OK Replace oil pressure relief valve.
oil pressure relief valve.

NOT
OK

Replace the oil pump.

8-20 Standard Practice Maintenance Manual

15 Sep 2019
 Troubleshooting
8-8. Engine Cylinders

Rough Idling

Perform “Cylinder Differential NOT Proceed according to

Pressure Check.” OK Inspection results

Standard Practice Maintenance Manual 8-21

15 Sep 2019
Troubleshooting

High Cylinder Head

Temperature

Measure CHT with digital NOT

Replace CHT sensor.
CHT gauge. OK

OK

Inspect cylinder cooling fins NOT

Clean cooling fins.
for dirt or obstructions. OK

OK

Inspect cylinder baffles and NOT Correct baffle and cowlings

cowling seals. OK adjustments accordingly.

OK

Inspect exhaust system for NOT Inspect exhaust system studs

gasket leak around manifold. OK and nuts for security.
LOOSE NUTS/
LEAKING GASKET
LOOSE
EXHAUST
STUDS Remove exhaust system
components from leaking
Remove exhaust system components from loose manifold according to primary
OK
studs according to primary ICA (NOTE: exhaust ICA ((NOTE: exhaust system on
system on naturally aspirated engines are naturally aspirated engines are
airframe components) instructions. Replace loose airframe components))
studs according to primary ICA. Install exhaust instructions. Install exhaust
system according to primary ICA. system with new gasket
according to primary ICA.
Perform “Engine Operational
Check” (Section 6) to verify fuel
system operation
OK

If only one or two cylinder appear

to be affected, perform “Fuel
Injector Operational Check”
(Section 8-3.4).

8-22 Standard Practice Maintenance Manual

15 Sep 2019
 Troubleshooting
8-9. Crankcase

Excessive Oil
Consumption / Loss

NO
Perform a visual inspection Perform Cylinder
LEAK
of the crankcase. NOTED Inspection.

OIL LEAKING

NOT NOT
Oil drain plug OK
Torque plug (Appendix B) OK
Engine Oil Change
OK
NOT Torque filter or screen NOT
Oil filter or screen OK OK
Engine Oil Change
(Appendix B)
OK

NOT
Oil pump OK Replace oil pump
OK

NOT
Oil cooler OK
Replace oil cooler
OK

NOT
Oil fill OK
Replace oil fill neck
OK

NOT Torque oil sump bolts

Oil sump OK (Appendix B)
OK

NOT Torque rocker fasteners NOT Replace rocker

Rocker cover gaskets OK OK
(Appendix B) cover gasket(s).
OK

NOT
Nose oil seal OK
Replace nose oil seal
OK

Perform Cylinder
Inspection

Loose Crankcase Accessories

Replace mounting studs

Inspect mounting threads and NOT (Appendix C) and install
re-torque fasteners (Appendix B). OK accessories according to
applicable instructions.

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Troubleshooting
8-9.1. Excess Crankcase Pressure

Excessive Crankcase Pressure

Remove the timing plug, if available, Remove the oil fill cap from the oil fill
from the crankcase. Temporarily tube. Temporarily install a modified
install a crankcase pressure plug oil fill cap connected to an airspeed
OR
(Part No. 630415) connected to an indicator. For engines with a
airspeed indicator. Torque the fittings separate oil gauge rod tube, connect
Indicated Airspeed (mph) Water Pressure
(Appendix B). the airspeed indicator to the dipstick
40 0.79
tube with a hose and clamp.
44 1 1.00
50 1.23
Perform ground engine run. 60 1.77
CAN NOT Monitor airspeed indicator. The 70 2.42
DUPLICATE
ON table at right indicates 80 3.16
GROUND representative simulated airspeed 4.0
90 2
versus gauge pressure.
100 4.94
Replace the oil filler cap 120 7.131
(bad seal). 140 9.729
HIGH 150 11.18
PROBLEM INDICATED
PERSISTS Ref: 1 psi = 2 in. Hg, 1 in. Hg = 13.6 in. 2HO
PRESSURE
1) Max limit on ground for A-65, C-75, C-85, C-90,
C-145, O-200, O-300, GO-300, IO-346
Replace the nose oil seal 2) Max limit on ground for 240, 360, 470, 520,
(see Section 10). 550, TIARA

Bypass the crankcase breather

system; repeat engine run.
NOT OK
OK

Remove obstruction from the

Air/Oil crankcase breather system;
YES Separator repeat engine run.
Installed?

NO

Bypass the Air/Oil Separator with

tubing. Repeat engine run.

OK

NOT Perform Cylinder Differential

Replace the Air/Oil Separator. OK Pressure Test (see Section 6).

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 Troubleshooting
8-10. Turbocharger and Exhaust System

General Troubleshooting
indicates a Turbocharger or Exhaust
System malfunction

Perform a Turbocharger and NOT Replace damaged or

Exhaust System Inspection. OK defective parts.

OK

Perform an
“Engine Operational Check” to
verify Manifold Pressure is within OK No further maintenance required.
operating limits. Adjust the
Wastegate Controller as required.

NOT
OK

NOT Maintenance
Replace Wastegate Controller Replace Wastegate OK
OK Complete
NOT
OK
OK

Maintenance
Maintenance Complete Replace Overboost Valve OK
Complete

Manifold Pressure Low/

Fluctuates

Perform a Turbocharger and NOT Repair damaged or

Exhaust System Inspection. OK defective parts.

OK

Monitor manifold pressure during Manifold

LOW Adjust Wastegate Controller
“Engine Operational Check.” Pressure?

FLUCTUATES

Replace Wastegate NOT Maintenance

Replace Wastegate OK
Controller OK Complete
NOT
OK
OK

Maintenance Maintenance
Replace Overboost Valve OK
Complete Complete

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Troubleshooting

Intentionally Left Blank

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 Engine Preservation and Storage
Chapter 9. Engine Preservation and Storage
9-1. Preserving and Storing an Engine
An engine which has been removed from the shipping container (uncrated) but not
installed or operated within 30 days should be placed back into storage. There are separate
procedures for:
1. storing an installed engine,
• temporary (from 30 days up to 90 days)
• indefinite (90 days or more)
2. storing a crated (uninstalled) engine
3. returning an engine to service after storage.
9-1.1. Engine Preservation Checklist
Create a copy of the engine checklist (Table 9-1, “Engine Preservation Checklist,” on
page 7) and record the serial number, date placed in storage and projected inspection dates
for each engine placed in storage. The checklist covers a 90-day storage cycle. Complete a
new checklist for every 90-day storage cycle and attach over previous checklists until the
engine is returned to service.
9-1.2. New or Unused Engine Storage
1. Determine the engine state (installed or crated) and projected period to be stored.
“Temporary” storage is defined as a period of 30 to 90 days when the engine will not
be used. “Indefinite” storage covers 90 days or more. If the engine state is an:
a. Installed engine and the storage period is:
1) 30-90 days, follow the instructions in Section 9-1.3, “Installed Engine,
Temporary Storage,” on page 9-1.
2) 90 days or more, follow the instructions in Section 9-1.4, “Installed Engine,
Indefinite Storage,” on page 9-3.
b. Crated engine (not installed in an aircraft), follow the instructions in Section 9-
1.5, “Crated Engine, Indefinite Storage,” on page 9-4.
2. Cover the engine with a plastic bag after preservation.
3. Install and attach the container cover to the base (if not already installed).
9-1.3. Installed Engine, Temporary Storage
“Temporary” storage is defined as a period of 30 to 90 days when the engine will not be
used. If the storage period is likely to exceed 90 days, prepare the engine for “Indefinite”
storage according to instructions in Section 9-1.4.
1. Change the engine oil according to Section 6-4.8, “Engine Oil Servicing,” on page 6-33.
Service the engine oil sump to the proper capacity with oil conforming to MIL-C-6529.

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Engine Preservation and Storage
WARNING
If preheaters are used to warm the engine, do not leave
preheaters on for longer than 24 hours to prevent corrosion.
2. Perform a “Preflight Inspection”; correct any discrepancies noted.
3. Perform an “Engine Start” and “Ground Run-up” according to the instructions in
Section 7-3.2 and Section 7-3.3, respectively.
4. Fly the aircraft for one hour at normal operating temperatures.
5. Allow the engine to cool after flight.
6. Disconnect and remove all spark plug leads.
NOTE: Specification for AN-4060, Ignition Lead Terminal Protector,
has been canceled. If AN-4060 protectors are not available, a plastic bag
with elastic band may be used to protect the end of the ignition terminal
from fouling.
7. Remove the top spark plugs from the engine; cover the ignition leads with AN-4060
(or equivalent) protectors.
WARNING
Disconnect all spark plug leads. Place the throttle in the
CLOSED position. Set the brake and chock the aircraft wheels.
Install aircraft tie-downs. Do not stand or place equipment
within the arc of the propeller.
8. With the piston at the Bottom Dead Center position, use a common garden sprayer
with clean reservoir and nozzle to spray atomized cylinder preservation oil that
meets MIL-PRF-46002, through the top spark plug hole of each engine cylinder.
Rotate the crankshaft as opposite cylinders are sprayed.
9. Stop the crankshaft at a position where no pistons are at Top Dead Center.
10. Spray each cylinder again; thoroughly coat all interior cylinder surfaces by moving
the nozzle from top to bottom of the cylinder while spraying. When all cylinders
walls are thoroughly coated, ensure no piston is positioned at Top Dead Center.
11. Install the top spark plugs; do not install the spark plug leads.
12. Seal all engine openings exposed to the atmosphere using suitable plugs and covers.
Attach a “REMOVE BEFORE FLIGHT” streamer to each location.
13. Attach a tag in a prominent location on the engine, preferably the propeller (or
storage container, if installed) with the following information:
DO NOT TURN PROPELLER - ENGINE PRESERVED
(preservation date)
14. Indicate the status of new or rebuilt engines which have not been placed in service
on the preservation tag.
NOTE: If the engine is not returned to service within 90 days of initial
temporary storage, it must be preserved according to the “Installed
Engine, Indefinite Storage” instructions in Section 9-1.4.

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 Engine Preservation and Storage
9-1.4. Installed Engine, Indefinite Storage
WARNING
Perform this procedure in an area free of sparks, flames, or
other ignition sources.
1. Change the engine oil according to the “Engine Oil Servicing” in Section 6-4.8.
Service the engine oil sump to the proper capacity with oil conforming to MIL-C-
6529.
WARNING
If preheater are used to warm the engine, do not leave
preheaters on for longer than 24 hours to prevent corrosion.
2. Perform an “Engine Start” and “Ground Run-up” according to the instructions in
Section 7-3.2 and Section 7-3.3, respectively.
3. Perform a Preflight Inspection; correct any discrepancies noted.
4. Fly the aircraft for one hour at normal operating temperatures.
5. Allow the engine to cool after flight.
WARNING
Disconnect all spark plug leads, place the Throttle in the
CLOSED position, set the brake and chock the aircraft wheels.
Install aircraft tie-downs, Do not stand or place equipment
within the arc of the propeller.
6. Disconnect and remove all spark plug leads.
NOTE: Specification for AN-4060, Ignition Lead Terminal Protector,
has been canceled. If AN-4060 protectors are not available, a plastic bag
with elastic band may be used to protect the end of the ignition terminal
from fouling.
7. Remove the top and bottom spark plugs from the engine and cover the ignition leads
with AN-4060 (or equivalent) protectors.
8. Install protective plugs (P/N 656816) in the bottom spark plug holes.
9. With the piston at the Bottom Dead Center position, use a common garden sprayer
(with clean reservoir and nozzle) to spray atomized cylinder preservation oil that
meets MIL-PRF-46002, through the top spark plug hole of each engine cylinder.
Rotate the crankshaft as opposite cylinders are sprayed.
10. Spray each cylinder again; thoroughly coat all interior cylinder surfaces by moving
the nozzle from top to bottom of the cylinder while spraying. When all cylinders
walls are thoroughly coated, ensure no piston is positioned at Top Dead Center.
11. Install dehydrator plugs MS27215-1 or MS27215-2 in each of the top spark plug
holes. Ensure that each dehydrator plug is dark blue in color when installed.
12. Attach a “REMOVE BEFORE FLIGHT” streamer tag to desiccant bags and place
the tagged desiccant bag in the exhaust pipes. Seal the exhaust pipe openings.

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Engine Preservation and Storage
13. Seal all other exposed engine openings with suitable plugs and covers. Attach
“REMOVE BEFORE FLIGHT” streamers to installed plugs and covers.
14. Affix a readily visible tag to the propeller (or storage container, if installed) with the
following information:
DO NOT TURN PROPELLER - ENGINE PRESERVED
(preservation date)
15. Indicate the status of new or rebuilt engines which have not been placed in service
on the preservation tag.
16. Make a copy of Table 9-1, “Engine Preservation Checklist,” on page 7. Enter the
serial number, storage date and next inspection due date on the form. Attach the
form to the engine.
17. For indefinite storage, visually inspect the dehydrator plugs at 15-day intervals.
Change the dehydrator plugs at the first indication (if any plug is not dark blue,
replace the dehydrator plug) of color change. If more than half the dehydrator plugs
change color, replace all desiccant material on the engine.
18. Repeat application of cylinder preservative application at 90 intervals.

9-1.5. Crated Engine, Indefinite Storage

Store engines awaiting installation in the original crate in a sheltered area, protected from
the elements. Factory new and rebuilt engines are preserved for 90 days prior to shipment
from the factory.
WARNING
Perform this procedure in an area free of sparks, flames, or
other ignition sources.
1. Monitor engines awaiting installation to ensure the preservation date.
2. Perform a Visual Inspection upon receipt of the engine; correct any discrepancies
noted.
3. Remove spark plugs, shipping plugs, or dehydrator plugs from top spark plug
bosses.
4. Rotate the crankshaft until the No. 1 piston is at the Bottom Dead Center (BDC)
position.
a. Use a common garden sprayer (with clean reservoir and nozzle) to spray
atomized cylinder preservation oil that meets MIL-PRF-46002, through the
cylinder top spark plug hole; thoroughly coat all interior cylinder surfaces by
moving the sprayer nozzle from top to bottom of the cylinder while spraying.
b. Rotate the crankshaft to position each cylinder at BDC and repeat application of
preservation oil to each cylinder.
c. Repeat application of preservative oil to each cylinder without rotating the
crankshaft.

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 Engine Preservation and Storage
d. When all cylinders walls are thoroughly coated, ensure no piston is positioned at
Top Dead Center.
e. Remove the oil fill gauge rod (dipstick) from the oil fill tube and spray
approximately two ounces of preservative oil through the oil filler tube. Reinstall
the oil fill gauge rod.
5. Install dehydrator plugs MS27215-1 or MS27215-2 in each of the top spark plug
holes. Ensure that each dehydrator plug is dark blue in color when installed.
6. Install a dehydrator plug (MS27215-1 or MS27215-2) in the crankcase breather tube
and wrap with moisture resistant tape to seal the breather opening.
7. Insert two desiccant bags (MIL-D-3464) in the induction inlet. Cover the opening
with an appropriately sized shipping plug or moisture resistant tape.
8. If an exhaust system is provided with the engine, insert a desiccant bag (MIL-D-
3464) in the exhaust outlet. If no exhaust is proved, Cover the opening with an
appropriately sized shipping plug or moisture resistant tape.
9. Seal exposed engine openings (open exhaust ports, induction plenum or throttle
inlet) with suitable plugs and covers.
10. Wrap the engine with the original shipping bag, place two desiccant bags (MIL-D-
3464) inside the shipping bag. Wrap the shipping bag around the base of the
shipping crate with moisture resistant tape and cover with the original shipping
crate.
11. Affix a readily visible tag to shipping crate with the following information:
DO NOT TURN CRANKSHAFT - ENGINE PRESERVED
(preservation date)
12. Indicate the status of new or rebuilt engines which have not been placed in service
on the preservation tag.
13. Make a copy of Table 9-1, “Engine Preservation Checklist,” on page 7. Enter the
serial number, storage date and next inspection due date on the form. Attach the
form to the outside of the shipping crate.
14. Visually inspect dehydrator plugs at 15-day intervals. Change the dehydrator plugs
at the first indication (if any plug is not dark blue, replace the dehydrator plug) of
color change. If more than half the dehydrator plugs change color, replace all
desiccant material on the engine.
15. Repeat application of cylinder preservative at 90 intervals.

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Engine Preservation and Storage
9-1.6. Return an Engine to Service after Storage
1. Remove seals and desiccant bags.
2. Remove cylinder dehydrators (or plugs) from top and bottom spark plug holes.
3. Change the engine oil according to the “Engine Oil Servicing” in Section 6-4.8.
Service the engine to the proper sump capacity with oil conforming to MIL-C-6529
Type II (Break-in oil, SAE J 1966 non-dispersant mineral oil).
4. Rotate propeller several revolutions by hand to remove preservative oil.
5. Remove AN-4060 protectors from the ignition leads.
6. Service and install spark plugs and leads according to the instructions in Section 6-
4.9.2, “Spark Plug Maintenance” and Section 6-4.9.3, “Ignition Harness
Maintenance”.
7. Clean and service engine and aircraft according to the Aircraft Manufacturer’s
instructions. Perform a visual inspection and correct any discrepancies noted.
8. Perform a normal engine start according to the Airplane Flight Manual or Pilot’s
Operating Handbook.
9. Conduct an “Engine Operational Check” according to instructions in Section 6-4.7;
correct any discrepancies.
10. Perform a “Flight Check” according to instructions in Section 7-2.4; correct any
discrepancies before releasing the aircraft for normal service.
11. Change engine oil and filter after first 25 hours of operation.

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 Engine Preservation and Storage
Table 9-1. Engine Preservation Checklist

Engine Serial Number: Date Placed in Storage

Inspection Due Completion Performed

Inspection Item Status Date Date By
Engine preserved and stored
according to the instructions in
Section 9-1.4 YES N/A / /
PASSED
15 day inspection CORRECTED / / / /
PASSED
30 day inspection CORRECTED / / / /
PASSED
45 day inspection CORRECTED / / / /
PASSED
60 day inspection CORRECTED / / / /
PASSED
75 day inspection CORRECTED / / / /
PASSED
90 day inspection CORRECTED / / / /
PASSED
90 day cylinder treatment CORRECTED / / / /
Engine removed from storage COMPLETED / / / /
* Check condition of dehydrator plug for discoloration. Contents should be dark blue in color. If plugs are discolored, remove and
replace with new plugs. If more than half the dehydrator plugs on the engine require replacement, remove and replace the desiccant
bags in the exhaust pipes with fresh desiccant bags and reseal the exhaust pipe.
** Treat each cylinder bore with MIL-PRF-46002.With the piston at the bottom dead center position, use a common garden sprayer (with
clean reservoir and nozzle) to spray atomized cylinder preservation oil that meets MIL-PRF-46002, (at room temperature) through the
top spark plug hole of each engine cylinder. Thoroughly cover all interior cylinder surfaces by moving the nozzle from top to bottom.
Rotate the crankshaft as opposite cylinders are sprayed. Ensure no piston is positioned at top dead center.
Inspector Notes:

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Engine Preservation and Storage

Intentionally Left Blank

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 Non-Overhaul Repair and Replacement
Chapter 10.Non-Overhaul Repair and Replacement
10-1. Parts Replacement
Procedures in this chapter apply to instances outside of overhaul when parts can be repaired
or replaced as a maintenance practice; some parts cannot be repaired and must be replaced.
Table 10-1, “Non-Overhaul Parts Replacement Reference” indicates items that must be
replaced, along with respective references for replacement instructions. Table 10-2, the
“Parts Repair Reference” lists items that may be repaired along with corresponding
references to the repair instructions. Unless otherwise indicated, instructions are in this
chapter.
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
NOTE: When replacing components according to the maintenance
procedures in this section, adhere to the service limits, in line with the
procedure as a guide for part re-use for each component. Use the overhaul
dimensional limits in the primary Instructions for Continued
Airworthiness when performing maintenance repairs if service limits are
not provided. 

Service limits in this section apply only to maintenance procedures and in
many cases are not identical to the overhaul limits in the primary
Instructions for Continued Airworthiness (Section 1-1.1)
.

Table 10-1. Non-Overhaul Parts Replacement Reference

Replaceable Item Reference Section
Alternator Section 10-4, “Alternator Replacement”
Crankshaft Nose Oil Seal Section 10-10, “Crankshaft Nose Oil Seal Replacement”
Fuel Injector Nozzles Table 10-3 and Section 10-2, “Fuel Injector Replacement”
Induction Drain Connector Section 10-3, “Induction Drain Connector Replacement”
Magneto Section 10-5, “Magneto Replacement”
Oil Filter Section 6-4.8, “Engine Oil Servicing”
Piston Section 10-8, “Piston Replacement”

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Non-Overhaul Repair and Replacement

Table 10-2. Parts Repair Reference

Repairable Item Reference Section
Crankcase Section 10-7, “Crankcase Repair”
Crankshaft Counterweights Section 10-9, “Crankshaft Repair”
Cylinder Section 10-6, “Cylinder Repairs”

Table 10-3. Parts Handling Guidelines

Parts/Components Handling Instructions
Parts that require protection from atmospheric dust and moisture should be
Wrapped new or rebuilt parts wrapped or boxed after acceptance inspection and remain wrapped until time of
installation
Handle spark plugs with clean, dry hands. Avoid dropping a spark plug. If a
Spark plugs spark plug is either dropped or damaged, discard it. Do not install any spark plug
that has been dropped or damaged.

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 Non-Overhaul Repair and Replacement
10-2. Fuel Injector Replacement
Refer to Section 10-2.1 for a brief explanation of fuel injector nozzle product identification.
Removal Installation instructions vary for naturally aspirated and turbocharged engines.
For naturally aspirated engines, refer to Section 10-2.4 and Section 10-2.5; for
turbocharged engines use the instructions in Section 10-2.2 and Section 10-2.3.
NOTE: Continental tests newly manufactured fuel injector nozzles and
manifold valves as a set during the assembly process. Individual fuel
injector nozzles may be replaced if unserviceable but we recommend
replacement of injectors as a complete set to ensure proper distribution of
fuel mixture to all cylinders and optimum engine performance.
10-2.1. Nozzle Identification
Continental fuel injector nozzles have undergone two phases of redesign since 1998.
Original nozzles were identified only by three-character nozzle size codes (Figure 10-1)
(First Generation) on one or two of the hexagonal wrench flats.
The first redesign extended the identification to four-characters, including the installed
cylinder position at the left-most character (Figure 10-1) (Second Generation) in the ID.
Fuel injector nozzles manufactured by Continental after Dec 2005 are etched on four faces
of the nozzle (Figure 10-1) (Third Generation). To select the proper replacement nozzles,
you must first identify which generation of nozzle is installed. If the removed injectors do
not conform to the new format, see Section 1-4.2 to cross-reference the correct
replacement nozzle part number. A factory service representative can assist in determining
the proper replacement nozzle based on the removed nozzle identification.

Figure 10-1. Fuel Injector Nozzle Identification, typical

Observe the markings in Figure 10-1. A three digit numeric code identifies the nozzle
orifice bore is stamped on two of the injector’s hexagonal wrench flats – ignore this
number! Adjacent to the three digit number, the injector is stamped on two of the
hexagonal wrench flats with a four digit code indicating the cylinder position number and
the nozzle flow; use this 4-digit number when assigning nozzles to cylinders. When
ordering replacement nozzles, specify the position number and nozzle flow for each
replacement nozzle required.

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Non-Overhaul Repair and Replacement
10-2.2. Fuel Injector Removal (Turbocharged Engines)
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
1. Turn the Ignition Switch to the OFF position and disconnect engine electrical power.
2. Remove airframe cowling, as required, to access the fuel injector nozzles.
NOTE: Where applicable for installed engine models, it may be necessary
to remove induction tubes (according to primary ICA) in order to gain
access to fuel injector nozzles.
3. Loosen the air reference sleeve “B” nuts (Figure 10-2, item 2) from each reference
sleeve (8) fitting on the common air for the side of the engine where the injector is
being removed to allow the reference line freedom of movement. Remove and discard
the compression seals (9).
4. Loosen “B” nuts on fuel lines (7), remove washers (5, 6); discard rubber washers (5).
5. Slide the reference sleeve (2) off the injector nozzle (1).
6. Remove fuel injector nozzles (1) with an Ideal Aviation Part No. 8167-IA (7/16”) or
8168-IA (1/2”) Injector Nozzle Removal/Installation Tool; remove and discard washers
(4) and O-rings (3) from nozzle.
7. Place protective caps or plugs over the open fuel connections.
8. Note the nozzle identification and cylinder position for reinstallation or replacement.
10-2.3. Fuel Injector Installation (Turbocharged Engines)
CAUTION: Ensure nozzle position numbers are matched to the
appropriate cylinder. Installing incorrect nozzles or nozzles in the
improper position will adversely affect engine performance.
1. Verify the cylinder position number (Figure 10-1) etched on the nozzle wrench flat
matches the intended cylinder. If the nozzle is a replacement, the cylinder position
number and nozzle flow must be a suitable for the intended cylinder position.
2. Purge the fuel system according to the “Fuel System Service” instructions in Section C-
8 to prevent fuel system contamination prior to connecting each injector line to the fuel
nozzle.
3. Apply clean, 50-weight aviation engine oil to a new washer (Figure 10-2, item 4) and
O-rings (3).
4. Install new washer (4) below the nut seat of the nozzle (1); apply a small amount of
Continental P/N 646943 anti-seize lubricant to the nozzle according to Figure 3-1; hand
tighten nozzle in the cylinder head; torque the nozzle with an Ideal Aviation Part No.

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 Non-Overhaul Repair and Replacement
8167-IA (7/16”) or 8168-IA (1/2”) Injector Nozzle Removal/Installation Tool to
Appendix B specifications.
5. Install new O-rings (3) on the nozzle (1).
6. Install the air reference sleeve (2) with a new rubber washer (5) and flat washer (6).
7. Install new compression seals (9) on the air reference line fittings and connect to the air
reference sleeve “B” nuts. Torque the air reference sleeve “B” nuts to Appendix B
specifications.
8. Connect the fuel lines to the fuel injector nozzles at each cylinder and torque the “B”
nuts to Appendix B specifications.
NOTE: If removed for installed engine models, it may be necessary to
reinstall removed induction tubes (according to primary ICA).
9. Perform an “Engine Operational Check” according to the instructions in Section 6-4.7.

Figure 10-2. Turbo Fuel Injector Nozzle Assembly, typical

1 Fuel Injector Nozzle 6 Washer

2 Air Reference Sleeve 7 Fuel Line
3 O-rings 8 Reference Line
4 Washer 9 Compression Seal
5 Rubber Washer

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Non-Overhaul Repair and Replacement
10-2.4. Fuel Injector Removal (Naturally Aspirated Engines)
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
1. Disconnect engine electrical power and turn the Ignition Switch to the OFF position.
2. Remove airframe cowling, as required, to access the fuel injector nozzles.
3. Loosen “B” nuts on fuel lines.
4. Remove fuel injector nozzles (1) with an Ideal Aviation Part No. 8167-IA (7/16”) or
8168-IA (1/2”) Injector Nozzle Removal/Installation Tool; remove and discard washers
(4) and O-rings (3) from nozzle.
5. Place protective caps or plugs over the open fuel connections.
NOTE: Ensure nozzle identification and cylinder position for
reinstallation or replacement.
10-2.5. Fuel Injector Installation (Naturally Aspirated Engines)
CAUTION: Ensure nozzle position numbers are matched to the
appropriate cylinder. Installing incorrect nozzles or nozzles in the
improper position will adversely affect engine performance.
1. Verify the cylinder position number (Figure 10-1) etched on the nozzle wrench flat
matches the intended cylinder. If the nozzle is a replacement, the cylinder position
number and nozzle flow must be a suitable for the intended cylinder position.
2. Purge the fuel system according to the “Fuel System Service” instructions in Section C-
8 to prevent fuel system contamination prior to connecting each injector line to the fuel
nozzle.
NOTE: There are three types of fuel injector nozzles used on naturally
aspirated engines. The screens and shields (Figure 10-3) on the short
reach nozzles are pressed in place on the injector nozzle and need not be
disassembled. The long reach nozzles on IO-550-G, N, P & R engines are
press fit with an O-ring installed on the upper flange. The O-ring must be
replaced after cleaning. Long reach injector nozzles on the remaining fleet
of naturally aspirated engines do not utilize an O-ring.
3. For IO-550-G, N, P & R model engines only, if fuel injectors were removed and
cleaned, new O-rings (Figure 10-3) are required prior to installation. Apply clean, 50-
weight aviation engine oil to the new O-ring and install one O-ring in the groove at the
top of the fuel injector nozzle. Install the screen and shroud over the upper portion of
the fuel injector nozzle.
4. For IO-550-G, N, P & R engines only, install a new copper washer at the base of each
injector nozzle.

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 Non-Overhaul Repair and Replacement
5. Apply a small amount of Continental P/N 646943 anti-seize lubricant to the nozzle
according to Figure 3-1; hand tighten nozzle in the cylinder head; torque the nozzle
with an Ideal Aviation Part No. 8167-IA (7/16”) or 8168-IA (1/2”) Injector Nozzle
Removal/Installation Tool to Appendix B specifications.
NOTE: The “B” nut connection is a dry seal. Do not apply any sealant to
the threads of the tapered fitting of the fuel injector nozzle or the “B” nut.
Reference Figure 3-2.
6. For IO-550-G, N, P & R engines only, install a new rubber washer followed by a steel
washer at the fuel inlet of each injector nozzle.
7. Connect the fuel line “B” nut to the fuel injector nozzle and torque to Appendix B
specifications.
8. Perform a normal “Engine Start” and “Ground Run-up” according to the aircraft AFM/
POH. Allow the engine to run-for no more than five minutes and inspect the fuel
injectors for leaks after “Engine Shutdown”.
CAUTION: Some early versions of the IO-550-G, N, P & R long
reach fuel injector nozzles feature two O-ring shoulders (groove). At
the time of assembly, install an O-ring only in the top groove.

Figure 10-3. Naturally Aspirated Engine Fuel Injector Nozzles

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10-3. Induction Drain Connector Replacement
Crossflow (induction ports above; exhaust ports below) cylinders are designed with a
tapped boss below the intake valve in the cylinder head. A connector, installed in the
tapped boss allows excess fuel to drain from the intake to avoid a hydraulic lock condition.
Updraft (intake and exhaust ports below the cylinder) cylinders incorporate induction
drains in the induction tubes. Instructions in the section apply to the crossflow cylinders
only.
10-3.1. Induction Drain Connector Removal and Cleaning
1. Disconnect the cylinder drain tubes from the connector fittings on the bottom side of
each cylinder head according to instructions in the Maintenance and Overhaul (or
Overhaul) Manual.
2. Remove the connector fitting (Figure 6-96) from each cylinder head. Visually inspect
the connector threads for physical damage; replace faulty connectors.
3. Clean connector fittings by immersion in lacquer thinner for several hours.
a. Stubborn stains may be polished with a fine nylon (Scotch Brite®) scouring pad.
b. Inspect the weep hole for varnish buildup obstructions; if the weep hole is
clogged, a small piece of 0.020” safety wire may be passed through the hole to
free the clog.
c. Allow the cleaned connector fittings to air dry.
4. If cleaning is unsuccessful, replace the connector fitting.
10-3.2. Induction Drain Connector Installation
1. Sparingly apply Part No. 646940 F/I sealant to the tapered male threads of the
connector.
2. Install the connector fitting in the cylinder head; torque 60-80 in. lbs. (reference
Appendix B specifications).
3. Connect cylinder drain tubes to the connector fittings with new seals according to the
instructions in the Maintenance and Overhaul (or Overhaul) Manual.

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10-4. Alternator Replacement
Replace the alternator when it fails to deliver the correct voltage and amperage to the aircraft
electrical system. If electrical malfunctions are isolated to the alternator, physical inspection
of the alternator must be accomplished before replacement. The engine may be equipped
with a direct drive alternator, a belt-driven alternator, or both. For Continental alternators,
refer to Table 1-2 for the appropriate instructions to service or overhaul the alternator.
Consult Section 10-4.3 for applicable continued airworthiness instructions or replace the
alternator with a new, rebuilt, or serviceable alternator during the 500 hour inspection.
On all GTSIO-520 and All 520 and 550 series engines with a Permold crankcase, a gear
driven alternator pad, forward of the No. 5 cylinder is driven off the crankshaft face gear.
In this manual, these alternators are designated as FWD . See Section 10-4.1 for removal
and installation instructions. C-75, C-85, C-90, C-115, C-125, C-145, E-165, E-185, E-
225, O-200, GO-300, GIO-300, O-300, IO-240, IOF-240, and all 360 series engines
feature an alternator mounting pad on the accessory case, driven off the camshaft gear.
These alternators are designated as AFT in this manual; see Section 10-4.2 for removal
and installation instructions.
10-4.1. Gear Driven Alternator Replacement, Forward Mount FWD

10-4.1.1. Gear Driven Alternator Removal FWD

Applicable Engines:
IO-520-B, BA, BB, C, CB, M, MB, NB, TSIO-520-B, BB, BE, D, DB, E, EB, J, JB, K, KB,
L, LB, N, NB, UB, VB, WB, IO-550-A, B, C, G, N, P, R, IOF-550-N, P, R, TSIO-550-B, C,
E, G, K, N, TSIOF-550-D, J, K, P, TSIOL-550, A, B, C
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
1. Turn the Ignition Switch to the OFF position and disconnect engine electrical power.
2. Disconnect the aircraft battery according to the aircraft manufacturer’s instructions.
3. Disconnect electrical connections from the alternator according to the aircraft
manufacturer’s instructions.
4. Remove the nut (Figure 10-4, item 10), washer (8), lock washer (9), and from the four
alternator mounting studs; discard the lock washers (9).
5. Remove the alternator (2) from the crankcase mounting studs.
CAUTION: Exercise care when cleaning the residue from the
mounting flange; mask the crankcase opening to avoid
contaminating the engine oil supply.
6. Remove and discard the gasket (1); clean any remaining gasket residue from the
crankcase flange with lacquer thinner.

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7. Place the alternator in a horizontal position, rotate the shaft in both directions. If the
shaft does not turn freely, rotor friction or bearing stress is indicated, or noticeable shaft
displacement is detected during rotation, replace the alternator.
8. Perform a “Gear Tooth Inspection” on the alternator drive coupling gear according to
the instruction in Section 11-1.1. If the drive coupling gear teeth are chipped, broken,
or otherwise damaged, replace the drive coupling according to instructions in
Section 10-4.1.2 and perform a “Foreign Object Contamination Inspection” according
to instructions in Section 6-5.7.
9. Inspect the drive coupling for serviceability. If the coupling exhibits damage or missing
material, replace the drive coupling and perform a “Foreign Object Contamination
Inspection” according to instructions in Section 6-5.7.
10.Perform a “Gear Tooth Inspection” on the alternator face gear according to the instruction
in Section 11-1.1. If the face gear teeth are chipped, broken, or damaged, disassemble
the engine and replace the crankshaft face gear.
11. Perform an “Alternator Drive Coupling Inspection” according to instructions in
Section 6-4.22.1.

Figure 10-4. Alternator and Drive Coupling

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10-4.1.2. Alternator Drive Coupling Removal FWD

Applicable Engines:
IO-520-B, BA, BB, C, CB, M, MB, NB, TSIO-520-B, BB, BE, D, DB, E, EB, J, JB, K, KB,
L, LB, N, NB, UB, VB, WB, IO-550-A, B, C, G, N, P, R, IOF-550-N, P, R, TSIO-550-B, C,
E, G, K, N, TSIOF-550-D, J, K, P, TSIOL-550, A, B, C
1. Remove the alternator from the crankcase according to the instructions in Section 10-4.1.1.
CAUTION: Remove and discard the spring coupling (Part No.
6409333 or 640934) if installed on the alternator. The elastomer
coupling superseded the spring couplings.
2. Remove and discard the cotter pin (Figure 10-4, item 7) and remove the castellated nut (4).
3. Remove the drive coupling assembly (5) from the alternator shaft.
4. Separate the thrust washer (6) and drive hub assembly (5).
5. Inspect, disassemble, troubleshoot, repair, and assemble Continental alternators
according to the Alternator Service Instruction (X30531). Reference the
manufacturer’s primary ICAs for all non-Continental alternators.
NOTE: If the alternator is manufactured for Continental by Hartzell
Engine Technologies, HET (dba Plane Power) consult Section 10-4.3 for
applicable airworthiness instructions. For all non-Continental alternators,
replace the alternator with a new, rebuilt, or serviceable unit.
10-4.1.3. Alternator Drive Coupling Installation FWD

Applicable Engines:
IO-520-B, BA, BB, C, CB, M, MB, NB, TSIO-520-B, BB, BE, D, DB, E, EB, J, JB, K, KB,
L, LB, N, NB, UB, VB, WB, IO-550-A, B, C, G, N, P, R, IOF-550-N, P, R, TSIO-550-B, C, E,
G, K, N, TSIOF-550-D, J, K, P, TSIOL-550, A, B, C
WARNING
If the shipping washer is not removed prior to installing the drive
coupling, the shipping washer will interfere with the crankshaft
face gear and damage the engine and alternator.
1. Remove the shipping spacer and washer from the alternator shaft and discard to prevent
interference with the crankshaft face gear.
WARNING
The thrust washer (6) must be installed with the bearing surface
(copper color) facing the alternator.
2. Install the drive coupling (5), and new thrust washer (6) on the alternator shaft.
3. Install the castellated nut (4) on the shaft. Secure the drive coupling with an Alternator
Drive Hub Spanner Wrench (see Section 2-1, “Special Tools”) and torque the castellated
nut (4) to the minimum value specified in Appendix B.

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4. If the slots of the nut do not align with the cotter pin hole in the alternator shaft, the
castellated nut may be torqued up to the maximum value in Appendix B. If the cotter
pin holes will not align with the nut slot within the torque range, replace the nut.
5. Install the new cotter pin (7) according to the “Cotter Pin Installation” instructions in
Section C-7, cut and bend the cotter pin according to the illustration in Figure 10-4 to
prevent it from touching the thrust washer and to attain clearance when installing the
alternator on the engine.
6. After drive coupling installation, inspect the drive coupling assembly for slippage
according to the instructions in Section 10-4.1.4.
7. Install the alternator according to “Gear Driven Alternator Installation” instructions in
Section 10-4.1.5.
10-4.1.4. Alternator Drive Coupling Slippage Inspection FWD

NOTE: Do not remove the drive coupling for the slippage inspection.
The spanner wrench is designed to secure the drive coupling on the shaft.
1. Secure the alternator in a shielded vise to prevent movement. Do not over-tighten.
CAUTION: Secure the outer diameter of the drive coupling
assembly. Allow the gear freedom of movement to prevent damaging
or shearing the elastomer coupling.
2. Secure the alternator drive coupling with an “Alternator Drive Hub Spanner Wrench
(Table 2-1); adjust the bolts using finger pressure only - do not torque the bolts.

Figure 10-5. Alternator Drive Hub Spanner Wrench

3. Measure drive coupling slippage using an “Alternator Drive Hub Torque Tool” (Figure
2-5) and currently calibrated torque wrench set to value for the drive coupling
condition specified in Table 10-4. Turn the hub through a 45° arc at a rate of 1° to 2°
per second. No slippage is permitted below the value specified in Table 10-4.
4. If the coupling slips with less torque applied than the value specified in Table 10-4, or
the coupling exhibits physical damage, discard and replace the alternator elastomer
drive coupling and repeat the slippage check on the new drive coupling.
Table 10-4. Alternator Drive Coupling Slippage
Coupling Assembly Condition Slippage Prohibited Below:
New coupling or coupling with less than 25 hours in service 180 in-lbs.
Coupling with more than 25 hours in service 140 in-lbs.

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10-4.1.5. Gear Driven Alternator Installation FWD

Applicable Engines:
IO-520-B, BA, BB, C, CB, M, MB, NB, TSIO-520-B, BB, BE, D, DB, E, EB, J, JB, K,
KB, L, LB, N, NB, UB, VB, WB, IO-550-A, B, C, G, N, P, R, IOF-550-B, C, N, P, R,
TSIO-550- B, C, E, G, K, N, TSIOF-550-D, J, K, P, TSIOL-550, A, B, C
Prior to alternator installation, perform an “Alternator Drive Coupling Slippage
Inspection” in Section 10-4.1.4 and install a serviceable drive hub according to
instructions in Section 10-4.1.3.
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
CAUTION: If the removed alternator exhibited gear tooth or
elastomer coupling damage, the engine must be inspected for foreign
object contamination prior to installing a new alternator.
1. Turn the Ignition Switch to the OFF position and disconnect engine electrical power.
2. Perform a “Gear Tooth Inspection” on the alternator face gear according to the instruction
in Section 11-1.1. If the face gear teeth are chipped, broken, or damaged, disassemble
the engine and replace the crankshaft face gear.
3. Install a new gasket on the alternator mounting studs.
4. Install the alternator on the mounting studs using four new lock washers, four plain
washers and four nuts. Torque the nuts to 150-180 in. lbs. in an alternating cross
pattern.
5. If the alternator had a grounding strap when it was removed, install the grounding strap
when installing the alternator.
6. Reconnect electrical connections at the alternator according to the aircraft
manufacturer’s instructions.
7. Consult the aircraft maintenance manual for instructions to reconnect ram air ducts, if
equipped, for alternator cooling air.
8. Reconnect the aircraft battery according to the aircraft manufacturer’s instructions.
9. Start the engine (“Engine Start” instructions in Section 7-3.2) and test the alternator
output according to the instructions in the Aircraft Maintenance Manual.

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10-4.2. Gear Driven Alternator Replacement, Aft Mount AFT

Applicable Engines:
C-75, C-85, C-90, C-115, C-125, C-145, E-165, E-185, E-225, GO-300, GIO-300, O-200,
O-300, IO-240, IOF-240, and all IO-360, LTSIO-360, TSIO-360
10-4.2.1. Gear Driven Alternator Removal AFT

WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
1. Turn the Ignition Switch to the OFF position and disconnect engine electrical power.
2. Disconnect the aircraft battery according to the aircraft manufacturer’s instructions.
3. Disconnect electrical connections from the alternator according to the aircraft
manufacturer’s instructions.
NOTE: The alternator gasket on 360 series engines is NOT integrated
with the tachometer drive adapter gasket.
4. For 360 series engines, proceed to the next step. On C-Series, O-200, IO-240, IOF-240
series engines only, remove the tachometer drive adapter, or tachometer drive adapter
pad cover, depending on, configuration, according to instructions in the primary ICA
(reference Section 1-1.1).
5. Remove three lock nuts (Figure 10-6, item 8) and washers (7) from the three alternator
mounting studs. Discard the lock nuts (8).
6. Remove the alternator (1) from the accessory case mounting studs.
CAUTION: Exercise care when cleaning the residue from the
mounting flange. Mask the accessory case opening to avoid
contaminating the engine oil supply.
7. Remove the gasket (6) and clean any remaining gasket residue from the accessory case
with lacquer thinner.
8. Rotate the crankshaft through two revolutions to perform a “Gear Tooth Inspection” on
the camshaft gear according to instruction in Section 11-1.1. If the camshaft gear teeth
are damaged, disassemble the engine and replace the camshaft gear.
9. Inspect the drive hub coupling for serviceability. If the coupling exhibits damage or
missing material, replace the drive hub and perform a “Foreign Object Contamination
Inspection” according to instructions in Section 6-5.7.
10.Place the alternator in a horizontal position, rotate the shaft in both direction. If the
shaft does not turn freely, rotor friction or bearing stress is indicated, or noticeable shaft
displacement is detected during rotation, replace the alternator.

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Figure 10-6. Alternator and Drive Hub

Typical for C-75, C-85, C-90, C-115, C-125, C-145, GO-300, GIO-300, O-300, IO-240, IOF-240
1 Alternator 4 Castellated Nut 7 Washer 10 Terminal Nut
2 Woodruff Key 5 Cotter Pin 8 Lock Nut 11 Washer
3 Drive Hub (single piece) 6 Gasket 9 Washer 12 Terminal Nut

Figure 10-7. Alternator and Drive Hub

Typical for E-Series, 360 Series engines

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10-4.2.2. Alternator Drive Hub Removal AFT

Applicable Engines:
C-75, C-85, C-90, C-115, C-125, C-145, E-165, E-185, E-225, GO-300, GIO-300, O-300,
IO-240, IOF-240, and all IO-360, LTSIO-360, TSIO-360
1. Remove the alternator according to the instructions in Section 10-4.2.1.
2. Remove the cotter pin (Figure 10-8 or Figure 10-9, item 4) and castellated nut (3);
discard the cotter pin (4).
3. Remove the drive hub assembly (1) from the alternator shaft.
10-4.2.3. Alternator Drive Hub Installation AFT

The alternator drive hub may be a one piece coupling, or an assembly of multiple parts.
Applicable Engines:
C-75, C-85, C-90, C-115, C-125, C-145, E-165, E-185, E-225, GO-300, GIO-300, O-300,
IO-240, IOF-240, and all IO-360, LTSIO-360, TSIO-360
1. For the one piece coupling only: Perform an “Alternator Drive Coupling Inspection”
according to the instructions in Section 6-4.22.2.
2. Align the slot in the alternator drive hub (1) with the Woodruff key and install the hub
on the shaft. For single piece drive hub proceed to step 4. For the multi-piece drive hub
assembly, continue with the next step.
3. For multi-piece drive hub assembly only:
a. Inspect the retainer (7) for physical damage; replace as required. Install the
retainer (7) on the shaft with the bushing tray facing away from the alternator.
b. Install the sleeve (6) on the alternator shaft.
c. Inspect the bushings (8) for physical damage, cracks, chips, or erosion. Replace
on condition. Install serviceable, or new, bushings (8) in the tray of the retainer.
d. Install the gear (5) on the shaft and align the drive lugs with the recess between
the bushings.
4. Install the castellated nut (3) on the threaded end of the alternator shaft to secure the
assembly.
5. Place the toothed portion of the drive hub gear in shielded vise jaws and tighten vise
just enough to prevent rotation during the torquing of the nut (3).
6. Using a currently calibrated torque wrench, torque the castellated nut (3) to the
minimum torque according to Appendix B specifications. If the slots in the nut do not
align with hole in the shaft, gradually increase torque to a maximum of 200 in. lbs. to
align the castellated nut (3) with the cotter pin hole. If alignment cannot be achieved
within the torque limits, replace the castellated nut (3).
7. Install a new cotter pin (4) through the nut and alternator shaft according to the
instructions in Appendix C-7. Cut and bend the cotter pin according to the instructions
in Figure 10-4 to avoid interference with mating surfaces when installing the alternator
on the engine.

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Figure 10-8. Multi-Part Alternator Drive Hub

1 Drive Hub 3 Castellated Nut 5 Gear 7 Retainer
2 Woodruff Key 4 Cotter Pin 6 Sleeve 8 Bushings

Figure 10-9. One Piece Alternator Drive Hub

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10-4.2.4. Gear Driven Alternator Installation AFT

Applicable Engines:
C-75, C-85, C-90, C-115, C-125, C-145, E-165, E-185, E-225, GO-300, GIO-300, O-300,
IO-240, IOF-240, and all IO-360, LTSIO-360, TSIO-360
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
1. Turn the Ignition Switch to the OFF position and disconnect engine electrical power.
2. Perform a “Gear Tooth Inspection” on the camshaft gear according to the instruction in
Section 11-1.1. If the camshaft gear teeth are chipped, broken, or damaged, disassemble
the engine and replace the camshaft gear.
3. If the drive hub assembly was removed, install the drive hub assembly according to
instructions in Section 10-4.2.3.
4. Install the new gasket (Figure 10-6 or Figure 10-7, item 6) on the accessory case studs.
5. Install the alternator (1) on accessory case studs.
WARNING
Forceful alternator installation can cause mount lug fracture. If
interference exists, inspect the mounting studs for bending;
replace bent studs.
6. Verify the alternator enters the crankcase without binding and the mounting flange is
properly seated against the crankcase. Do not force the alternator into position. If there
is stud interference with the mounting lug holes while mounting the alternator, do not
force the alternator over the studs.
7. Verify the alternator pilot enters the accessory case pilot bore squarely. Do not force the
alternator pilot to fit into the pilot bore.
8. Secure the alternator with washers (7) and new lock nuts (8); torque the lock nuts
according to Appendix B specifications.
9. For C-Series, O-200, IO-240 and IOF-240 engines only, install the tachometer drive
adapter or tachometer drive adapter pad cover according to instructions in the primary
ICA (reference Section 1-1.1).
10.Connect the alternator wiring according to the aircraft manufacturer’s instructions. If
the alternator had a grounding strap when it was removed, install the grounding strap
when installing the alternator.
11. Start the engine (“Engine Start” instructions in Section 7-3.2) and test the alternator
output according to the instructions in the Aircraft Maintenance Manual.

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10-4.3. Alternator Service Instructions
Continental alternators listed in Table 10-5 on page 10-20 are manufactured for
Continental by Hartzell Engine Technologies LLC.
Continental provides removal and installation instructions for the alternator part numbers
listed in the first column of Table 10-5 in their respective maintenance and overhaul
manuals (as identified in Section 1-1.1 of this manual).
• Reference the latest revision of Continental Alternator Service Support Manual,
X30531 for Continental alternators, P/N 646843, 646845, 649304, or 649305.
• Reference M-2 Maintenance and Overhaul Manual for Continental alternator P/N
657377.
Reference the manufacturer’s primary Instructions for Continued Airworthiness (ICA) for
non-Continental alternators.
Detailed alternator maintenance instructions for Hartzell alternator part numbers listed in
the second column of Table 10-5 are provided in Hartzell Engine Technologies OE-A2,
Maintenance and Overhaul Manual (Revision 4 or later).
Contact:
Hartzell Engine Technologies LLC (HET) dba Plane Power®
2900 Selma Highway
Montgomery, AL 36108
1-888-461-6077 within the Continental U.S.
1-334-386-5400 International
www.hartzellenginetech.com

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Table 10-5. Alternator Cross Reference

Hartzell Alternator 
Continental Alternator  Part Number (P/N) Alternator Characteristics
Part Number (P/N) referenced in OE-A2 (Operating Voltage, Output Amperage, Drive Interface)
633661 ES4001 15V/60A Gear Driven

633962 ES4004 28V/38A Gear Driven

634442 ES4006 28V/60A Gear Driven

641668 ALT-9522 24V/50A Gear Driven

641670 ALX-9524 12V/70A Gear Driven

643008 ALX-9525B 12V/70A Gear Driven

649281 ES4002 12V/80A Gear Driven

649292 ES4017 28V/70A Belt Driven

649283 ES4009 28V/70A Belt Driven

652485 ALX-8523 12V/70A Belt Driven

652486 ALT-8520 24V/50A Belt Driven

653344 ES4029 28V/75A Gear Driven

654200 ES4024LP 28V/85A Belt Driven

655997 ES6012-6 12V/60A Belt Driven

656802 ES10024 24V/100A Gear Driven

656955 ES4024LP-2 28V/85A Belt Driven

657199 ES7024-14 24V/70A Belt Driven

658257 ES4024LP-3 28V/85A Belt Driven

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10-5. Magneto Replacement
10-5.1. Continental Magneto Removal
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
1. Turn the Ignition Switch to the OFF position and disconnect engine electrical power.
2. Disconnect the Magneto Sensor (Figure 10-10, item 2), if equipped, from the bottom of
the magneto.
3. Remove the nut (8) and lock washer (9) and disconnect the airframe wiring from the
magneto ground terminal according to the aircraft manufacturer’s instructions.
4. Remove four screws (25) from the cable outlet plate (part of item 3 connected to
ignition wires). Remove and discard the gasket (10).
CAUTION: Remove the magneto carefully to avoid dropping the
bushings or retainers into the crankcase.
NOTE: Magnetos with dog ear mounts, such as those used on the C-75,
C85, C90, O-200, and IO-240 engine models do not use magneto
retainers (7).
5. Remove nuts (5), lock washers (6), and magneto retainers (7) from either side of
magneto.
NOTE: The gasket (24) is only required on pressurized magnetos
6. Remove and discard gasket (24).
NOTE: If replacing the magneto, retain the pressurization fittings for the
replacement magneto. pressurization fittings are not part of the magneto.
7. On pressurized magnetos only, remove clamp (16) and disconnect hose (16) at 90°
fitting (19) from magneto.
8. Refer to the Ignition System Master Service Manual (X40000) for magneto
maintenance instructions.
9. Perform an “Ignition System Inspection” according to instructions in Section 6-4.15.

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10-5.2. Continental Magneto Installation
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
1. Turn the Ignition Switch to the OFF position and disconnect engine electrical power.
2. Complete the “Crankshaft Top Dead Center Alignment” in Section 6-4.9.1.1.
3. Verify the magneto drive coupling bushings and retainer are properly installed.
4. Perform steps 2-3 of the “Magneto to Engine Timing” in Section 6-4.9.1.2.
NOTE: Figure 10-10 depicts a pressurized magneto; instructions are the
same for non-pressurized systems, except as noted.
5. Remove the pressurization fitting (Figure 10-10, item 19) (plug, if non-pressurized
magneto) from the magneto(s). Turn the impulse coupling backward until the marked
distributor gear tooth is centered in the window.
6. Without turning the magneto coupling, hold the magneto in the position it will occupy
when installed.
a. Align the gear coupling slot and impulse coupling lugs by pulling the magneto
gear out and turning it to the desired position.
b. Push the gear back into the meshed position.
7. Install the new gaskets (24) on the magneto flange.
NOTE: Magnetos with dog ear mounts, such as those used on the C-75,
C85, C90, O-200, and IO-240 engine models do not use magneto
retainers (7).
8. Carefully insert the magneto in the crankcase/accessory case, aligning the drive
coupling lugs mate with the drive bushing slot. Install four holding washers (7), lock
washers (6) and nuts (5); hand-tighten the nuts at this time.
9. If the removed magneto is fitted with a magneto tachometer sensor (2), install the
sensor in the magneto housing and torque the tachometer sensor to Appendix B
specifications.
10.On pressurized magnetos only, apply Continental Part No. 658517to the male threads
of the magneto pressurization fitting (19) and install the pressurization fitting (19)
removed for inspection. Torque the pressurization fitting to Appendix B specifications.
11. Complete “Magneto to Engine Timing” in Section 6-4.9.1.2.
12.Disconnect the timing light from magnetos. Attach the airframe wiring harness to the
magneto ground terminal according the aircraft manufacturer’s instructions.
NOTE: Unpressurized magnetos do not require a gasket between the
magneto and the cable outlet plate.

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13.Install the spark plugs and ignition harness according to instructions “Ignition System
Maintenance” in Section 6-4.9.
14.Start the engine according to the “Engine Start” instructions in Section 7-3.2
instructions and perform a “Magneto RPM Drop Check” according to the instructions
in Section 6-4.7.5.

Figure 10-10. Continental Ignition System

Typical Pressurized Six Cylinder Ignition System

1 Magneto 8 Nut 15 Hose 22 Washer, Flat
2 Magneto Sensor 9 Lock Washer 16 Clamp 23 Nut, Self Locking
3 Ignition Harness 10 Gasket 17 Hose 24 Gasket
4 Kit, Ignition System 11 Spark Plug 18 Tee 25 Screw Assembly
5 Nut 12 Filter Assembly 19 Fitting, 90° Elbow
6 Lock Washer 13 Reducer -Drain Fitting 20 Clamp
7 Retainer, Magneto 14 Hose 21 Bolt

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10-5.3. Champion (Slick) Magneto Removal
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power prior to commencing maintenance. Do not stand or place
equipment within the rotational arc of the propeller.
1. Turn the Ignition Switch to the OFF position and disconnect engine electrical power.
2. Disconnect the airframe wiring from the magneto ground terminal according to the
aircraft manufacturer’s instructions.
NOTE: Figure 10-11 depicts a pressurized magneto; instructions are the
same for non-pressurized systems, except as noted.
3. Remove the screws (Figure 10-11) (part of item 3 connected to ignition wires) from the
ignition harness cap and separate the ignition harness cap from the magneto.
NOTE: If replacing the magneto, retain the pressurization fittings for the
replacement magneto. pressurization fittings are not part of the magneto.
4. On pressurized magnetos only, remove clamp (11) and disconnect hose (10) at 90°
fitting (15) from magneto.
5. Disconnect magneto sensor (23), if equipped, from the bottom of the magneto. Inspect
the magneto sensor for cracks or physical damage; verify the vent is hole open and free
of obstructions; replace on condition.
CAUTION: Remove the magneto carefully to avoid dropping the
bushings or retainers into the crankcase.
NOTE: Magnetos with dog ear mounts, such as those used on the C-75,
C85, C90, O-200, and IO-240 engine models do not use magneto
retainers (6).
6. Remove nuts (4), lock washers (5), and magneto retainers (6) from either side of
magneto. Carefully remove the magneto from the crankcase, disengaging the drive
coupling lugs from the drive bushing slot.
7. Remove and discard gasket (3).
8. Perform an “Ignition System Inspection” according to instructions in Section 6-4.15.
9. Replace the magneto with a new, rebuilt, or serviceable unit.

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10-5.4. Champion (Slick) Magneto Installation
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
1. Turn the Ignition Switch to the OFF position and disconnect engine electrical power.
2. Complete the “Crankshaft Top Dead Center Alignment” in Section 6-4.9.1.1.
3. Perform steps 2-3 of the “Magneto to Engine Timing” in Section 6-4.9.1.2.
4. Insert T118 timing pin in “L” or “R” hole (depending on magneto rotation) in the
distributor block. Turn rotor in the opposite direction of rotation until the pin engages
the gear.
5. Without turning the magneto coupling, hold the magneto in the position it will occupy
when installed.
a. Align the gear coupling slot and impulse coupling lugs by pulling the magneto
gear out and turning it to the desired position.
CAUTION: Remove the T118 timing pin before rotating the
crankshaft to prevent magneto damage.
b. Push the gear back into the meshed position and remove the T118 timing pin
from the magneto.
6. Verify the magneto drive coupling bushings and retainers are serviceable and properly
installed. Install new gaskets (Figure 10-11, item 3) on the magneto flange.
NOTE: Magnetos with dog ear mounts, such as those used on the C-75,
C85, C90, O-200, and IO-240 engine models do not use magneto
retainers (6).
7. Carefully insert the magneto in the crankcase/accessory case, aligning the drive
coupling lugs with the drive bushing slot. Secure the magneto to the crankcase with
retainers (6), lock washers (5) and nuts (4); hand-tighten the nuts at this time. Install the
ventilation plug removed for inspection.
8. Complete “Magneto to Engine Timing” in Section 6-4.9.1.2.
9. Reconnect the tachometer sensor, if equipped, and torque to Appendix B specifications.
10.On pressurized magnetos only, connect the pressurization hose (10) to the 90° fitting
(15) and secure with hose clamp (11); torque the clamp (11) to Appendix B
specifications.
11. Disconnect timing light from magnetos. Attach the magneto ground wire according the
aircraft manufacturer’s instructions.
12.Install the spark plugs and ignition harness according to instructions “Ignition System
Maintenance” in Section 6-4.9.

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13.Start the engine according to the “Engine Start” instructions in Section 7-3.2
instructions and perform a “Magneto RPM Drop Check” according to the instructions
in Section 6-4.7.5.

Figure 10-11. Champion (Slick) Ignition System

Typical Pressurized Six Cylinder Ignition System

1 Magneto 7 Spark Plug 13 Filter Assembly 19 Washer
2 Ignition Harness 8 Hose 14 Drain 20 Clamp
3 Gasket 9 Hose 15 Elbow 21 Vent Bushing
4 Nut 10 Hose 16 Hose Bracket 22 Filter Kit
5 Lock Washer 11 Clamp 17 Bolt 23 Tachometer Sensor
6 Retainer, Magneto 12 Tee 18 Nut-Self Locking

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10-5.5. Magneto Filter Replacement
Pressurized magnetos incorporate a desiccant filter to trap moisture that could cause
arcing at higher altitudes. Serviceable desiccant material in the filters is white in color;
replace the filter when the desiccant material turns dark. If the filter requires replacement,
inspect the internal magneto components for moisture and corrosion.
10-5.5.1. Continental Magneto Filter Replacement
1. Inspect the magneto housing for cracks according to the appropriate Magneto Service
Support Manual (Section 1-2.5, “Related Publications”). Inspect the magneto internal
parts for evidence of moisture or corrosion according to the Magneto Service
Instructions.
2. Remove magneto filter and hoses:
a. Loosen hose clamps (Figure 10-12, item 4) and remove the filter (6), plug (7),
hoses (1, 2 & 3) and clamps (4).
b. Discard the filter (6), plug (7) and hoses (1, 2 & 3).
NOTE: For continued service, replace hoses and clamps on condition;
replace the filter assembly and hoses at overhaul.Where complete filter
assembly replacement instructions are provided, perform applicable steps
required to return the ignition system to service.
3. Install new magneto filter and hoses:
a. Install new hoses (3) between the tee (5) and the elbow fittings (8); secure the
hoses (3) with clamps (4). Tighten but do not torque clamps.
b. Connect a new hose (2) on the open side of the tee (5) and secure with a clamp (4).
Tighten but do not torque clamp.
c. Connect a new hose (1) to the upper deck reference pressure fitting on the intake
manifold and secure with a clamp (4). Tighten but do not torque clamp.
d. Remove the shipping plugs and inspect the new filter (6) for cracks. Verify the
reducer/drain plug (7) is installed in the filter (6) drain hole.
e. If a clamp is used to secure the filter assembly to the engine:
1) Loosen the screw (9) and locknut (10) securing the cushion clamp (12).
2) Insert the new filter assembly (6) in the cushion clamp (12) with the arrow
pointing toward the magnetos and the drain tube pointing downward.
3) Secure the cushion clamp (12) with a screw (9), washers (11) and new lock
nut (10); tighten the fasteners (9 & 10) to Appendix B specifications.
f. Loosen two clamps and place them on the open ends of hoses (1 & 2). Connect
the new filter assembly (6) to the hoses (1 & 2) with the arrow on the filter
toward the magnetos and the drain pointing down.
g. Adjust hoses (1, 2 & 3) to minimize twisting stress and torque clamps (4) to
Appendix B specifications.

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Figure 10-12. Continental Pressurized Magneto Filter, typical

1 Hose 5 Tee 9 Screw 13 * Filter Kit

2 Hose 6 Filter Assembly 10 Nut, Self-Locking
3 Hose 7 Drain 11 Washer
4 Clamp 8 Elbow 12 Clamp

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10-5.5.2. Champion (Slick) Magneto Filter Replacement
1. Inspect the magneto housing for cracks according to the appropriate Magneto Service
Instructions (Section 1-2.5, “Related Publications”). Inspect the magneto internal parts
for evidence of moisture or corrosion according to the Magneto Service Instructions.
2. Remove magneto filter and hoses:
a. Loosen hose clamps (Figure 10-13) (4) from the hoses (1 & 2) at each end of the
filter (6); remove the filter (6) from assembly hoses (1 & 2) and clamps (4)
b. Inspect the hoses (1, 2 & 3) and fittings (5 & 8) for security and serviceability.
Replace cracked or brittle hoses.
NOTE: For continued service, replace hoses and clamps on condition;
replace the filter assembly and hoses at overhaul.Where complete filter
assembly replacement instructions are provided, perform applicable steps
required to return the ignition system to service.
3. Install new magneto filter and hoses:
c. Remove the shipping plugs and inspect the new filter assembly (6) for cracks.
Verify the reducer/drain plug (7) is installed in the filter drain hole.
a. Connect new hoses (3) to the tee (5) fitting 180° apart and secure with hose
clamps (4). Connect the open ends of the hoses (3) to the 90° fittings (8) and
secure with clamps (4). Connect a new hose (1) to the remaining fitting on the tee
(5) and secure with a clamp (4).
b. Connect the short end of a 90° hose (2) to the upper deck reference pressure
fitting on the intake manifold and secure with a clamp (4).
c. Insert the new filter assembly (6) in the cushion clamp (13) with the arrow
pointing toward the magnetos and the drain tube pointing downward. Secure the
cushion clamp (13) to the bracket (9) with a screw (10), washers (12) and new
lock nut (11); tighten the fasteners (10 & 11) to Appendix B specifications.
d. Connect the hoses (1 & 2) to the new filter; secure the hoses (1 & 2) to the filter
with clamps (4).
e. Adjust hoses (1, 2 & 3) to minimize twisting stress and torque clamps (4) to
Appendix B specifications.

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NOTE: Magneto orientation will vary depending on engine application.

Figure 10-13. Champion (Slick) Pressurized Magneto Filter, typical

1 Hose 5 Tee 9 Hose Bracket 13 Clamp

2 Hose 6 Filter Assembly 10 Screw 14 Vent Bushing
3 Hose 7 Drain 11 Nut-Self Locking 15 Filter Kit
4 Clamp 8 Elbow 12 Washer

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10-6. Cylinder Repairs
1. Remove suspect cylinders according to the instructions in the primary engine
instructions for continued airworthiness (ICA).
2. Perform the “Cylinder Inspections” in Section 6-4.11. After inspection, refer to the
“Cylinder Repair vs. Replacement Guidelines” in Table 10-6 to determine if the
cylinder can be repaired or if replacement is required.
3. Refer to “100% Parts Replacement Requirements” and “Mandatory Replacement
Parts” in Appendix C-2 to determine the replacement items for either in service repair
or overhaul.

Table 10-6. Cylinder Repair vs. Replacement Guidelines

Condition Corrective Action
Cylinder with radial fin crack extending to the root of a fin Replace1 the cylinder
Broken, bent (or straightened), or pitted cylinder head or barrel fins2 Replace1 the cylinder
Power stroke stress on cylinder barrel; heavy rust or pitting, indentation; chafing or cracks
on cylinder barrel Replace1 the cylinder

Cracks in cylinder head structure Replace1 the cylinder

Cracked or eroded valve seat bore Replace1 the cylinder
Static seal leakage or leakage from head to barrel seal or crack in head or barrel Replace1 the cylinder
Discolored/burned paint, Replace1 the cylinder
Piston pin scoring or damage to the cylinder bore (usually due to overheating) Do Not Repair3
Blistered paint on the cylinder barrel Replace1 the cylinder
Cylinder head-to-barrel junction movement Replace1 the cylinder

Low differential pressure coupled with excessive oil consumption Repair or replace 4 the
cylinder
Scratches in the honed surface of the cylinder wall or cylinder bore Repair the cylinder
Pitting, sharp dents or chafing in fin tips less than 0.050 inches (1.3 mm) deep Repair the cylinder
1. Replacement cylinders are available in several configurations, starting with a basic assembly and progressing to cylinders with more
components installed:
- Cylinder and Valve Assembly (includes the Basic Cylinder Assembly plus valve components).
- Loaded Cylinder and Valve Assembly (Cylinder and Valve Assembly plus rocker shaft, piston, piston rings, and gasket set).
- Cylinders for most engine models are available in standard honed steel, through hardened, or nickel silicon carbide plated
- Reference the Continental web site for the latest parts and service information.
2. Bent barrel fins may remain in service if fin is not bent more than one-half the distance to the next fin. If cylinder head or barrel fins are bent
more than half the distance to the next fin, replace the cylinder.
3. Do not attempt to remove overheating damage by grinding the cylinder bore to the next allowable oversize. Cylinder barrel overheating
destroys material strength.
4. If the cylinder is otherwise acceptable on inspection and the fits and clearances provide enough tolerance that the cylinder can be ground
and honed or plated, repair the cylinder; otherwise replace the cylinder.

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10-6.1. Cylinder Replacement
10-6.1.1. Cylinder Removal
WARNING
Turn the Ignition Switch OFF, disconnect the battery from the
engine and confirm continuity between the magneto capacitor
and aircraft ground before commencing maintenance to avoid
uncommanded engine starts during maintenance. Do not stand
or place equipment within the arc of the propeller.
If one or more cylinders require removal for in-service inspection, replacement or repair,
use the following guidelines:
1. Remove the aircraft cowling and baffles according to the aircraft maintenance manual.
2. Disconnect the spark plugs and ignition harness from the subject cylinder(s) according
to the instructions in the primary ICA (reference Section 1-1.1).
3. Remove the induction tubes and exhaust system from the subject cylinder(s) according
to the instructions in the primary ICA.
4. Disconnect the fuel injection lines from the subject cylinder(s) according to the
instructions in the primary ICA.
5. Disconnect cylinder drains, if equipped, according to primary ICA instructions.
6. If installed, disconnect the CHT sensors (probes) from the subject cylinder(s)
according to the instructions in the primary ICA.
7. During engine cylinder component removal, inspect components for wear and
conformance to dimensional criteria. Replace components based on the following:
a. Only parts that meet service limits may remain in service or be re-used.
b. If a part fails to meet a service limit, or is found in the “100% Parts Replacement
Requirements” or “Mandatory Overhaul Replacement Parts” in Appendix C-2,
replace it with a new or serviceable part.
8. Remove the valve train from the affected cylinders according to the instructions in the
primary ICA.
CAUTION: Removing cylinder flange nuts relieves the through-bolt
clamping force on the crankcase. Do not remove cylinder flange nuts
from more than one cylinder at a time. Do not turn the crankshaft
with through-bolt nuts removed. A rotational check will be
performed after cylinder installation to verify crankshaft main
bearing integrity in the crankcase.
9. Using the appropriate wrenches, carefully remove the flange nuts from the cylinder
base flange.
10.As the last pieces of fastening hardware are removed, cradle the cylinder in your arm
for support.

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CAUTION: The piston will be damaged if allowed to drop as the
cylinder is withdrawn.
11. While supporting the cylinder, carefully pull the cylinder outward in a straight plane
with one hand, keeping the other hand free to catch the piston as the cylinder is
withdrawn to prevent damage to the crankcase or cylinder.
CAUTION: Piston ring reinstallation is not recommended. If the
piston rings are removed for any reason, discard the removed piston
rings and install a new set of piston rings, with end gaps adjusted for
the destination cylinder.
12.Remove the piston pin and piston from the connecting rod. Inspect the piston and
piston pin according to the instructions in the primary ICA. If piston ring removal is
required, discard the piston rings and obtain, gap and install a new set of piston rings
according to the instructions in the primary ICA.
13.Remove the cylinder o-ring (or packing). Wrap the old cylinder base o-ring (or
packing) in a figure 8 pattern (Figure 10-14) around four of the crankcase studs and
stretch the two vertical segments of the packing over the connecting rod to secure it.

Figure 10-14. Cylinder Base O-Ring supporting Connecting Rods

14.Before commencing any cylinder repairs, perform a static leak check on the cylinder:
CAUTION: Do not allow the fiber drift to contact the valve spring
retainer or rotocoil.
a. Place a fiber drift on the rocker arm directly over the valve stem.
b. Tap the drift several times with a hammer to dislodge any debris that may be
between the valve face and seat.
c. Invert the removed cylinder with the spark plugs installed.
d. Fill the inverted cylinder bore with nonflammable solvent.
15.Look for leaks in the cylinder head to barrel junction. If the cylinder head and barrel
seal is leaking, discard the cylinder. If the intake or exhaust seat seals or the spark plug
seals are leaking, note the discrepancy and repair according to the instructions in the
primary ICA.

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16.Disassemble, clean, inspect, and make appropriate repairs to return the cylinder to the
published service limits according to the instructions in the primary ICA.
10-6.1.2. Cylinder Installation
Replace worn or out of tolerance components based on the following criteria:
• Only parts that meet the service limits may remain in service.
• If a part has reached a service limit tolerance, it must be replaced with a part that con-
forms to the specified new part tolerances or service limits.
• Clean cylinders and pistons according to the instructions in the primary ICA.
• Perform fluorescent penetrant, magnetic particle inspections according to instructions
in Section 11-2 and dimensional inspections on specified cylinder and piston parts
according to instructions in the primary ICA.
• Install serviceable lifters in the same location from which they were removed.
• Assemble cylinders which meet the inspection criteria and service limits according to
the instructions in the primary ICA with serviceable pistons and new piston rings.
WARNING
Do not apply any form of sealant to the crankcase cylinder
deck, chamfer, cylinder mounting flange, cylinder base O-ring,
or cylinder fastener threads. The use of RTV silicone, Gasket
Maker or any or other sealant on the areas listed above during
engine assembly will cause a loss of cylinder deck stud or
through-bolt torque. Subsequent loss of cylinder attachment
load, loss of main bearing crush or fretting of the crankcase
parting surfaces will occur. The result will be cylinder
separation, main bearing movement, or oil starvation and
catastrophic engine failure. USE ONLY CLEAN 50 WEIGHT
AVIATION ENGINE OIL ON SURFACES LISTED.
1. Inspect a new cylinder base o-ring (or packing) for cracks or deformities. If
serviceable, lubricate the new cylinder base o-ring with clean 50-weight aviation
engine oil.
2. Install the new cylinder base O-ring (or packing), lubricated with clean 50-weight
aviation engine oil on the cylinder base flange; verify the O-ring is not twisted on the
cylinder base flange after installation.
3. Lubricate cylinder through-bolt and deck stud threads using clean 50-weight aviation
engine oil.
4. Install a serviceable piston, fitted with new piston rings, and piston pin partially in the
cylinder bore.
5. Carefully rotate the crankshaft, placing the connecting rod of the cylinder being
installed in the outermost position. Remove the packing that was installed for
connecting rod support.
6. Line the piston up with the connecting rod and slide the piston pin into the connecting
rod.

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7. Using a ring compressor, compress the piston rings and push the cylinder until the
fourth piston ring is positioned inside the cylinder barrel.
8. Remove the ring compressor and push the cylinder assembly against the crankcase
cylinder deck with the stud holes aligned.
CAUTION: Engine crankcases featuring the seventh stud and
associated hardware use beveled seat brackets, part numbers
646297 and 646298 in combination with a self-aligning nut, part
number 646312. The spherical flange nut and the beveled seat
bracket work together to align the brackets on the seventh stud.
Cylinder flange hold down nuts and crankcase through-bolt nuts
feature a flat seat to evenly distribute fastener torque to the cylinder
mating flange.
9. While supporting the cylinder, install, but do not torque, the cylinder base (flange)
fasteners (reference Figure 10-15).
a. Ensure the cylinder base stud threads, through-bolt threads, and nut threads are
lubricated with clean, 50-weight aviation engine oil.
a. Install the cylinder base flange nuts on the cylinder base studs, finger tight.
b. Install flanged through-bolt nuts at the through-bolts, finger tight.
c. For engines featuring the seventh stud, position the cylinder hold down brackets
on the seventh stud to overlap the cylinder base flange and secure with the self-
aligning, spherical nut.

Figure 10-15. Cylinder Base (Flange) Fasteners

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10.For cylinder replacement, torque the cylinder fastening hardware according to the
“Cylinder Torque” instructions in Section 10-6.1.3.
11. Rotate the crankshaft through multiple revolutions to verify smooth rotation of the
crankshaft. If rotation is not smooth or binding is evident, disassemble the engine to
determine the cause. Verify crankshaft end play (end clearance) is within the tolerance
specified in the primary ICA. If no end play is present, disassemble the engine to
determine the cause.
12.Install the valve train and pushrods according to the instructions in the primary ICA.
13.Install cylinder baffles and baffle supports (if equipped), as required by the instructions
in the primary ICA.
14.Connect cylinder drains, if equipped, according to primary ICA instructions.
15.Install fuel injectors and connect the fuel injection lines according to the instructions in
the primary ICA.
16.Install the induction and exhaust system according to the primary ICA instructions.
CAUTION: Service the engine with SAE J1966 mineral oil for
engine break-in.
17.Service the engine with mineral oil according to instructions in Section 6-4.8.
18.Apply a light coating of LPS® Procyon (or LPS 3®) heavy duty corrosion inhibitor to
the through-bolt studs, washers, and flanged through-bolt nuts on -470, -520, and -550
series engines.
19.Perform a leak check on the fuel injection system according to the instructions in the
primary ICA.
20.Install the spark plugs and ignition harness according to the instructions in the primary
ICA.
21.Perform an initial engine run according to the instructions in the primary ICA.
22.Install the aircraft cowling and aircraft-supplied accessories according to the aircraft
manufacturer’s instructions.
23.Perform an “Engine Operational Check” and adjust engine fuel system to meet engine
model specifications according to the instructions in Section 6-4.7.
24.Perform a “Flight Check” according to the instructions in Section 7-2.4 prior to release
to normal operation.
25.Follow the “Engine Break-In” instructions in Section 7-2.4.1 for the first 25 hours of
operation.
26.Perform a “25-Hour Initial Operation Inspection” in Section 6-4.2 after the first 25
hours of engine operation. When oil consumption has stabilized, replace the mineral oil
with ashless dispersant aviation engine oil according to Section 6-4.8.

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10-6.1.3. Cylinder Torque
CAUTION: This cylinder torque procedure is for individual
cylinder installation. For complete engine assembly and torque,
refer to instructions in the primary ICA.
1. Lubricate the cylinder base stud threads, through-bolt threads and nut threads on
BOTH sides of the engine with clean, 50-weight aviation oil.
WARNING
Failure to torque through-bolt nuts on both sides of the engine
may result in a loss of main bearing crush, main bearing shift,
crankshaft fracture, and engine failure.
2. Install and torque the through-bolt nuts and cylinder base nuts to one half of the final
torque value specified in Appendix B in the sequence shown in Figure 10-16.
3. Torque the through-bolt nuts and cylinder base nuts to the full final torque value
specified in Appendix B in the sequence shown in Figure 10-16. Torque the through-
bolt nuts on both sides of the engine (even if only one cylinder is being installed).
NOTE: Seventh studs are not used on all installations. For single cylinder
torque, the seventh stud locations are torqued last at each cylinder
location.

Eight Bolt Flange Six Bolt Flange

Figure 10-16. Cylinder Torque Sequence

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10-6.2. Cylinder Position Numbers
Original cylinders have a position number stamped on the edge of the base flange. New cylinders
must have a position number stamped in the location shown in Figure 10-17.
WARNING
Do not stamp or etch the cylinder position on the piston. Pistons
are not stamped with position numbers. To mark the piston
with installed position, use a felt tip marker or attach a tag
indicating the installed position.

Figure 10-17. Cylinder Position Number Location

10-6.3. Cylinder Head Repair

WARNING
Do not perform any structural weld repairs on the cylinder
head. Welding the cylinder head structure can destroy the
assembly preloads and casting strength resulting in cylinder
assembly failure.
Replace cracked or damaged cylinders. Do not attempt to repair a cracked cylinder head.

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10-6.4. Cylinder Fin Tip Repair
CAUTION: Do not attempt to straighten bent cylinder fins. Replace
the engine cylinder if the barrel fins exhibit pitting, sharp
indentation, or chafing damage greater than 0.050 inch deep. Do
NOT weld cylinder barrel fins or cylinder barrels (see Section 10-
6.4, “Cylinder Fin Tip Repair”).
Bent cylinder barrel fins may continue in use provided the fin is not bent more than one-
half the distance to the next barrel fin. Do not attempt to straighten cylinder barrel fins. If
barrel fins are bent more than one-half the distance to the next fin, replace the cylinder.
Pitting, sharp indentations or chafing damage in the fin tip LESS than 0.050 inch deep
may be blended with a fine grit disk or stone as follows:
1. Blend the area smooth so no sharp edges remain. Ensure the original fin contours
remain.
2. Inspect the area for cracks and if no cracks are present, clean the surface thoroughly
according to instructions in Chapter 12.
3. Perform a Magnetic Particle Inspection on the cylinder barrel or Fluorescent Penetrant
Inspection on the head, depending on the area repaired.
10-6.5. Cylinder Bore Inspection
Inspect the cylinders according to the instructions in the primary ICA.
1. Repair cylinder bosses (valves and valve train, spark plug, and fuel injector) using the
instructions in the primary ICA. Regrinding the NiC3 cylinder bore is not practical, due
to the hardness of the nickel silicon carbide plating, therefore, cylinder bore grinding is
not permitted on NiC3 cylinders to perform routine maintenance.
2. Perform a fluorescent penetrant inspection (according to primary ICA instructions) on
the cylinder head to determine airworthiness using suitable measuring equipment.
3. Verify the cylinder bore is within service limits using suitable measuring equipment.
4. Check bore for signs of distress.
5. Check (visually and dimensionally) seats and guides; replace as necessary, according to
the primary ICA.
10-6.6. Cylinder Barrel Repair
WARNING
Cylinder Barrel Repair requires FAA certification. If you are
not certified, do not attempt to repair the cylinder barrel.
If the cylinder passes the visual inspection and static leak check at the cylinder head to
barrel junction, the cylinder barrel may be ground to the next authorized oversize
dimension by an FAA Part 145 Repair Stations certified to grind engine cylinders. These
facilities grind and hone the cylinder bore using a cam-controlled grinder to grind the
cylinder barrel to the next authorized oversize dimension specified in Section 10-6.11.

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After grinding the cylinder barrel to the next authorized oversize dimensions, perform a
Magnetic Particle Inspection on the cylinder bore and identify the cylinder with the
correct bore size by steel-stamping the barrel flange with the appropriate oversize
designation as depicted in Figure 10-17. If a cylinder has been ground, the cylinder bore
must be honed according to instructions in the primary ICA (Ref: Section 1-1.1).
10-6.7. Cylinder Bore Honing
“Honing” is a form of “low-stock” removal grinding. Grinding determines the cylinder
size, honing improves the shape. Honing is a self-truing grinding process. If a cylinder has
been ground, or required grinding to achieve it’s serviceable limits and condition, the
cylinder bore must have be ground according to instructions in the primary ICA (Ref:
Section 1-1.1).
If a cylinder requires maintenance honing (and not grinding), perform the cylinder bore
honing procedure under the following circumstances:
• when replacing piston rings
• to restore the cylinder bore cross hatch pattern
1. Inspect the cylinder barrel wall for corrosion, pitting and scoring. Discard any cylinder
exhibiting any of these unacceptable, non-conforming conditions.
2. Hone the cylinder bore using a wet honing process and hone stones that will produce a
surface finish as specified in Table 10-7 for Steel Hardened or Nickel Carbide
Cylinders (NiC3).
• Consult with your hone manufacturer to ensure appropriate honing lubricant.
• Consult with your hone manufacturer to ensure compatibility with NiC3 surface
and hardness specifications (see Table 10-7). Successful results have been
obtained using Brush Research Mfg., P/N GBD512600BC (5” and 5-1/4” bores).
3. After wet honing, the bore finish must show a cross hatch pattern. The included angle
of the cross hatch measured perpendicular to the axis of the cylinder is 22°- 32°.
Inspect the hone pattern taken at 100X magnification. An acceptable cross hatch
pattern must be cleanly cut and free of torn and folded metal (see Figure 10-18).
NOTE: Honed turnaround areas up to 0.5 inch from the skirt and barrel
stop are exempt from cross hatch angle requirements.
4. Measure the surface finish using a Contact Profilometer.
5. After honing, clean the cylinder thoroughly using hot soapy water and a rotating, stiff
bristled scrub brush to remove all honing material from the cylinder.
6. Rinse the cylinder with hot water to remove soap residue.
7. Dry the cylinder completely; repeat Section 10-6.7, steps 1-6. to verify cylinder barrel
serviceability.
8. The surface finish of the cylinder barrel bore must conform to the specifications listed
in Table 10-7. If the honed cylinder passes inspection, thoroughly coat the cylinder bare
steel surfaces with clean, 50-weight aviation engine oil.

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Table 10-7. Cylinder Bore Surface Finish Specifications
Nickel Carbide
Steel Hardened (NiC3)
Symbol Description Cylinder Range Cylinder Range
Ra Arithmetic average surface roughness 30-60 micro inches 3-8 micro inches
Sk Skew, measure of plateau -1 to -3.5 N/A
R3Z Three point height, distance between third highest 130-275 micro inches N/A
peak and third lowest valley
RPM/Rz Ratio of mean peak to total depth of pattern <0.35 N/A
RZDIN Average maximum height of the profile N/A Must be between 6
and 12 times Ra
N/A Bore Surface Hardness (for hone selection only) N/A 320 HV minimum
(Vickers)

Figure 10-18. NiC3 Cylinder Bore Cross Hatch

10-6.8. Cylinder Stud Replacement

CAUTION: Rosan ring lock studs have been replaced by stainless
steel studs on the Gold Standard cylinder configurations. Cylinders
originally configured with Rosan studs are not candidates for retrofit
to stainless steel exhaust studs.
Replace exhaust manifold studs, regardless of condition, at overhaul. Check the stud
alignment using a tool maker’s square. Replace studs that are bent, loose, or damaged
according to the “Stud Replacement” instructions in Section C-6. Install the new studs to
the specified heights listed in primary ICA (Ref: Section 1-1.1).

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10-6.9. Spark Plug Heli-coil Replacement
Equipment Required
• Heli-coil Extracting Tool
• Heli-coil Installation Tool
• Heli-coil No. 520-2 Expansion Tool
1. Before attempting to remove a damaged heli-coil insert, use a sharp pointed tool to pry
the teeth at the outer heli-coil end away from the cylinder head metal.
2. Tap the Extracting Tool into the insert until firmly seated; remove the heli-coil.
3. Using the proper size mandrel on the Installation Tool, place a new stainless steel heli-
coil in the cutout side of the Installation Tool and engage the driving tang toward the
threaded end.
4. Engage the tang with the slotted end of the driving mandrel and wind the insert into the
thread sleeve, compressing the insert.
5. Hold the sleeve so the heli-coil can be seen through the slot in the threaded end.
6. Turn the mandrel crank until the insert starts into the cylinder. If the sleeve is not in
contact with the head surface, grip the sleeve and mandrel and turn until the sleeve
touches lightly.
WARNING
The heli-coil insert end must not protrude into the combustion
chamber after it has been installed.
7. Wind the heli-coil into the cylinder head until its toothed end lies within the first full
thread. The teeth should be in position to enter the depressions made by the original
insert. If driven too far, the insert will emerge in the combustion chamber and will have
to be wound through and removed.
8. When the heli-coil is in the correct position, use long-nose pliers to bend the driving
tang back and forth across the hole until it breaks off at the notch.
9. Coat the threaded end of the No. 520-2 Expanding Tool with Alcoa® thread lube or a
mixture of white lead and oil.
10.Screw the No. 520-2 Expanding Tool into the new insert until its final thread forces the
teeth firmly into the cylinder head metal.

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10-6.10. Cylinder Protective Coatings
1. Clean the exterior cylinder head surface.
2. Apply a protective coating of Alodine on the cylinder head exterior surface according
to the manufacturer’s instructions.
3. Thoroughly clean the entire cylinder with mineral spirits and air dry.
CAUTION: Do not paint the cylinder flange nut seats, skirt, or
flange-to-crankcase mating surface.
4. Mask the cylinder flange nut seat contact surfaces, cylinder skirt and flange-to
crankcase mating surfaces.
CAUTION: Repeated application of paint to the cylinder head and
barrel will act as an insulator and inhibit the cylinder’s ability to
dissipate heat.
5. Apply a protective coating of specified enamel paint or equivalent (Section 3,
“Lubricants, Sealants, and Adhesives”) to the cylinder according to instructions in the
primary ICA.
6. After the paint dries completely, remove all masking materials.
7. Coat all bare steel surfaces with clean 50-weight aviation engine oil.
8. Store the cylinder assembly in a clean protected area until cylinder installation.

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10-6.11. Cylinder Bore and Piston Fit Specifications
CAUTION: Dimensional limits and repair instructions in this section
do not apply to Nickel Carbide (NiC3™) plated cylinders
manufactured prior to 2018. Refer to the latest revision of Continental
Service Document SB15-6, “NiC3 Cylinder Assemblies,” for
dimensional fits and limits, and airworthiness instructions.
Specifications in this document provide the following:
• Cylinder bore dimensions - New minimum/maximum, service limits (for continuing
cylinders in service between major overhaul(s)) and oversize service limits.
• Piston to cylinder clearance specifications for coated or uncoated pistons.
• Piston ring gaps and designated location in cylinder to measure ring gaps.
• Piston diameters, piston skirt diameters, and pin to dome height dimensions.
For disassembly, inspection, repair and assembly instructions, consult the applicable
engine Instructions for Continued Airworthiness (Section 1-1.1).
NOTE: Service limits in this section apply only to maintenance
procedures and in many cases are not identical to the overhaul limits in
the primary Instructions for Continued Airworthiness (Section 1-1.1) Use
the overhaul dimensional limits in the primary ICA when performing
maintenance repairs if service limits are not provided.
The Gold Standard project streamlined many of the unique cylinder dimensional
characteristics established through generations of product improvements to a common
design specification shared with all engine models sharing the same cylinder bore size.
Engine serial numbers 1006000 (and subsequent) and engine cylinder assemblies with
part number 658XXX (and later) conform to the Gold Standard design specifications. In-
service engines with earlier cylinder assembly part numbers may continue to use the pre-
Gold standard specifications, where applicable, until cylinder replacement.
The “New Limits MIN & MAX” dimensions for D, X, and Y diameters identify cylinder
barrel machining characteristics of new and authorized oversize (AO) dimension
cylinders.
Only the D and the X diameters are used to determine the serviceability of the cylinder
barrel. No wear limit is given for Y diameter because it is used for machining reference
only. For consistency, measure cylinder bore D and X dimensions in the plane through the
spark plug holes; repeat at a right angle (90°) to the first measurement and then average
the two results.
To determine out of round, measure first in the plane through the spark plug holes; repeat
the measurement at a right angle (90°) to the first measurement and then subtract the
smaller dimension from the larger. The difference must not exceed the out of round limit
specified.
New or authorized oversize cylinder bore dimensions must be used at engine overhaul.
Service limits may be used to return cylinders to service on engines that have not reached
their published TBO. Do not return any cylinder to service that cannot be machined to
conform to the dimensional limits specified in this manual.

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Piston ring gaps and cylinder dimensions must be maintained within the specifications
provided in this manual. If the cylinder is machined to the next larger AO size, piston
rings of the same AO size must be installed in the machined cylinder.
Piston specifications are presented in tabular form, (Table 10-25). Column 2, non-coated
pistons (with untreated skirt or graphite treated skirts pistons) were discontinued in 1998
and are provided for reference only.
CAUTION: Verify the cylinder, piston, and piston ring part numbers
are the correctly specified part number for the installation. Installation
of incorrect parts will cause engine damage and engine malfunction.

Figure 10-19. 5.250 Inch Cylinder Measurement Locations

Table 10-8. 5.250 Inch Cylinder Barrel Dimensions1

Applicable to Pre-Gold Standard: IO520, GTSIO520, TSIO520, IO550, IOF550,TSIOL550
Post-Gold Standard: IO346, IO520, LIO520, GTSIO520, LTSIO520, TSIO520, IO550, IOF550, TSIO550, TSIOF550, TSIOL550
“D” Diameter “X” Diameter “Y” Diameter
(inches) (inches) (inches)

Service Service Service

Size Minimum Maximum Limit Minimum Maximum Limit Minimum Maximum Limit
STD. 5.251 5.253 5.256 5.247 5.250 5.257 5.244 5.247 N/A
.005 5.256 5.258 5.261 5.252 5.255 5.262 5.249 5.252 N/A
.010 5.261 5.263 5.266 5.257 5.260 5.267 5.254 5.257 N/A
.015 5.266 5.268 5.271 5.262 5.265 5.272 5.259 5.262 N/A
1. Cylinder bore out of round: new cylinder must not exceed 0.001” in barrel above flange; service limit must not exceed 0.003” at measured
diameters.

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Table 10-9. 5.250 Inch Cylinder Barrel Dimensions1

Applicable to Pre-Gold Standard: IO346, TSIO550 (all except N), TSIOF550
“D” Diameter “X” Diameter “Y” Diameter
(inches) (inches) (inches)

Service Service Service

Size Minimum Maximum Limit Minimum Maximum Limit Minimum Maximum Limit
STD. 5.252 5.254 5.257 5.248 5.251 5.258 5.245 5.248 N/A
.005 5.257 5.259 5.262 5.253 5.256 5.263 5.250 5.253 N/A
.010 5.262 5.264 5.267 5.258 5.261 5.268 5.255 5.258 N/A
.015 5.267 5.269 5.272 5.263 5.266 5.273 5.260 5.263 N/A
1. Cylinder bore out of round: new cylinder must not exceed 0.001” in barrel above flange; service limit must not exceed 0.003” at measured
diameters.

Table 10-10. 5.250 Inch Piston to Cylinder Clearance1

IO346, TSIO550, TSIOF550
Piston in Cylinder (new)

5.250 Inch Piston Pre-Gold Standard Post-Gold Standard

All Non-Coated 0.008 - 0.011 LOOSE 0.007 - 0.010 LOOSE
Manganese Phosphate Coated 0.009 - 0.012 LOOSE 0.008 - 0.011 LOOSE
1. Measure clearance perpendicular to piston pin bore at “D” diameter Measure below 4th ring groove
perpendicular to piston pin bore.

Table 10-11. 5.250 Inch Piston to Cylinder Clearance1

IO520, LIO520, GTSIO520, LTSIO520, TSIO520, IO550, IOF550
5.250 Inch Piston Piston in Cylinder (new)
All Non-Coated
0.008 - 0.011 LOOSE
Manganese Phosphate Coated
1. Measure clearance perpendicular to piston pin bore at “D” diameter Measure below 4th ring groove
perpendicular to piston pin bore.

Table 10-12. 5.250 Inch Piston to Cylinder Clearance1

TSIOL550
5.250 Inch Piston Piston in Cylinder (new)
All Non-Coated 0.007 - 0.010 LOOSE
Manganese Phosphate Coated 0.008 - 0.011 LOOSE
1. Measure clearance perpendicular to piston pin bore at “D” diameter Measure below 4th ring groove
perpendicular to piston pin bore.

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Figure 10-20. 5.000 Inch Cylinder Measurement Locations

Table 10-13. 5.000 Inch Cylinder Barrel Dimensions1
Applicable to E-Series: O470, IO470, TSIO470
“D” Diameter “X” Diameter “Y” Diameter
(inches) (inches) (inches)
Service Service Service
Size Minimum Maximum Limit Minimum Maximum Limit Minimum Maximum Limit
STD. 5.001 5.003 5.006 4.997 5.000 5.007 4.994 4.997 N/A
.005 5.006 5.008 5.011 5.002 5.005 5.012 4.999 5.002 N/A
.010 5.011 5.013 5.016 5.007 5.010 5.017 5.004 5.007 N/A
.015 5.016 5.018 5.021 5.012 5.015 5.022 5.009 5.012 N/A
1. Cylinder bore out of round: new cylinder must not exceed 0.001” in barrel above flange; service limit must not exceed 0.003” at measured
diameters.

Table 10-14. 5.000 Inch Piston to Cylinder Clearance1

All O470 Series (except O470-4, 13, 13A, K, L, R, & S), IO470, TSIO470-B, C, & D, E-Series
5.000 Inch Piston Piston in Cylinder (new)
All Non-Coated
0.011 - 0.014 LOOSE
Manganese Phosphate Coated
1. Measure clearance perpendicular to piston pin bore at “D” diameter. Measure at the piston pin centerline
perpendicular to piston pin bore.

Table 10-15. 5.000 Inch Piston to Cylinder Clearance1

O470-4, 13, 13A, K, L, R, & S
5.000 Inch Piston Piston in Cylinder (new)
All Non-Coated
0.009 - 0.012 LOOSE
Manganese Phosphate Coated
1. Measure clearance perpendicular to piston pin bore at “D” diameter. Measure at the bottom of piston skirt
perpendicular to piston pin bore.

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Figure 10-21. 4.438 Inch Cylinder Measurement Locations

Table 10-16. 4.438 Inch Cylinder Barrel Dimensions1

Applicable to ALL IO240, IOF240, IO360, LTSIO360, and TSIO360
“D” Diameter “X” Diameter “Y” Diameter
(inches) (inches) (inches)
Service Service Service
Size Minimum Maximum Limit Minimum Maximum Limit Minimum Maximum Limit
STD. 4.437 4.439 4.442 4.434 4.437 4.444 4.431 4.434 N/A
.005 4.442 4.444 4.447 4.439 4.442 4.449 4.436 4.439 N/A
.010 4.447 4.449 4.452 4.444 4.447 4.454 4.441 4.444 N/A
.015 4.452 4.454 4.457 4.449 4.452 4.459 4.446 4.449 N/A
1. Cylinder bore out of round: new cylinder must not exceed 0.001” in barrel above flange; service limit must not exceed 0.003” at measured
diameters.

Table 10-17. 4.438 Inch Piston to Cylinder Clearance1

Applicable to ALL IO240, IOF240, LTSIO360, IO360, and TSIO360
4.438 Inch Piston Piston in Cylinder (new)
All Non-Coated
0.009 - 0.012 LOOSE
Manganese Phosphate Coated
1. Measure clearance perpendicular to piston pin bore at “D” diameter. Measure at the piston pin centerline
perpendicular to piston pin bore.

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Figure 10-22. 4.062 Inch Cylinder Measurement Locations

Table 10-18. 4.062 Inch Cylinder Barrel Dimensions1

Applicable to C75, C85, C90, C115, C125, C145, O200, O300, GO300
“X” Diameter Straight Barrel
(inches)
Service
No Choke
Size Minimum Maximum Limit
STD. 4.0615 4.0635 4.0665
.005 4.0665 4.0685 4.0715 N/A
.015 4.0765 4.0785 4.0815
1. Cylinder bore out of round: new cylinder must not exceed 0.001” in barrel above flange; service
limit must not exceed 0.003” at measured diameters.

Table 10-19. 4.062 Inch Piston to Cylinder Clearance1

Applicable to C75, C85, C90, C115, C125, C145, O200, O300, GO300
4.062 Inch Piston Piston in Cylinder (new)
All Non-Coated 0.008 - 0.011 LOOSE (C90, C145, O200, O300, GO300)
Manganese Phosphate Coated
0.009 - 0.012 LOOSE (C75, C85, C115)
1. Measure clearance perpendicular to piston pin bore at “D” diameter. Measure C75, C85, C115, and C125
at the bottom of piston skirt perpendicular to piston pin bore. Measure C90, C145, O200, O300 and
GO300 above 4th ring perpendicular to piston pin bore.

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Figure 10-23. Ring Gap Measurement Location

Table 10-20. Ring Gap Specifications

5.250 Inch Cylinder - All IO346, IO520, GTSIO520, LIO520, LTSIO520, TSIO520,
IO550, IOF550, TSIO550, TSIOF550, TSIOL550
Gaps

Pre-Gold Post-Gold
5.250 Gage Pre-Gold1 Standard Post-Gold Standard
RING Part Number Diameter Standard Service Standard Service
Ring Set 654716A1 N/A N/A N/A N/A N/A
Top Ring 648005 0.026 - 0.034 0.032 - 0.046 0.032 - 0.055 0.029 - 0.043 0.029 - 0.052
Second Ring 654719 0.032 - 0.040 0.038 - 0.052 2
0.038 - 0.061 2
0.035 - 0.049 2
0.035 - 0.0582
Oil Control Ring 6547173 0.012 - 0.022 0.018 - 0.034 0.018 - 0.043 0.015 - 0.031 0.015 - 0.040
Fourth Ring / Skirt 648008 0.012 - 0.022 0.018 - 0.034 0.018 - 0.043 0.015 -0.031 0.015 - 0.040
1. Applies to Pre-Gold Standard piston ring gaps on IO346, TSIO550-C, E, G, K, and TSIOF550-D, J, K, and P.
2. Gap for second ring is nominally 0.006” larger than the top ring.
3. Part No. 654717 consists of expander (Part No. 654718) and ring (Part No. 649250-1).

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Table 10-21. Ring Gap Specifications
5.000 Inch Cylinder - All E-Series, O470, IO470, TSIO470
5.000 Gage
RING Part Number Diameter Gap Service Gap
Ring Set, 6 cyl. 649226A1 N/A N/A N/A
Top Ring 648009 0.024 - 0.032 0.027 - 0.041 0.027 - 0.050
Second Ring 648010 0.020 - 0.030 0.023 - 0.039 0.023 - 0.048
Oil Control Ring 648011 0.012 - 0.022 0.015 - 0.031 0.015 - 0.040
Fourth Ring / Skirt 648012 0.012 - 0.022 0.015 - 0.031 0.015 - 0.040

Table 10-22. Ring Gap Specifications

4.438 Inch Cylinder - ALL IO240, IOF240, IO360, LTSIO360, and TSIO360
4.4375 Gage
RING Part Number Diameter Gap Service Gap
Ring Set, 4 cyl. 649225A2 N/A N/A N/A
Ring Set, 6 cyl. 649225A1 N/A N/A N/A
Top Ring 648039 0.024 - 0.032 0.022 - 0.037 0.022 - 0.046
Second Ring 648040 0.030 - 0.038 1
0.028 - 0.043 1
0.028 - 0.0521
Oil Control Ring 648041 0.010 - 0.020 0.008 - 0.025 0.008 - 0.034
Fourth Ring / Skirt 648042 0.012 - 0.022 0.010 - 0.027 0.010 - 0.036
1. Gap for second ring is nominally 0.006” larger than the top ring

Table 10-23. Ring Gap Specifications

4.062 Inch Cylinder - C75, C85, C90, C115, C125, C145, O200-A, B, & C, O300, GO300
4.0625 Gage
RING Part Number Diameter Gap Service Gap
Ring Set, 4 cyl. 649632A2 N/A N/A N/A
Ring Set, 6 cyl 649632A3 N/A N/A N/A
Top Ring 649632 0.023 - 0.031 0.020 - 0.034 0.020 - 0.043
Second Ring 638110 0.029 - 0.037 0.026 - 0.040 0.026 - 0.049
Third Ring 638110 0.029 - 0.037 0.026 - 0.040 0.026 - 0.049
Oil Control Ring 638111 0.015 - 0.025 0.012 - 0.028 0.012 - 0.037

Table 10-24. Ring Gap Specifications

4.062 Inch Cylinder - O200D ONLY
4.0625 Gage
RING Part Number Diameter Gap Service Gap
Ring Set 657480 N/A N/A N/A
Top Ring 657479 0.023 - 0.031 0.020 - 0.034 0.020 - 0.043
Second Ring 638110 0.029 - 0.037 0.026 - 0.040 0.026 - 0.049
Third Ring 657548 0.015 - 0.025 0.012 - 0.028 0.012 - 0.037

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Table 10-25. Engine to Piston Cross Reference
NOTE: *Non-coated pistons (with untreated skirt or graphite treated
skirt) were discontinued in 1998 and are provided for reference only.

Non-coated Piston
Manganese
*graphite treated Phosphate Coated
Engine Model *untreated skirt skirt Piston Piston Diameter
C75, C85, C115, C125 646287 654841 4.0514-4.0524
N/A
(6.3:1 comp. ratio) N/A 654841P015 4.0664-4.0674
C90, C145 654749 654853 4.0522-4.0532
O200A, B N/A
O300A, C, D N/A 654853P015 4.0672-4.0682

O200D N/A N/A 657562 4.0522-4.0532

GO300 646279 N/A 654858 4.0522-4.0532
IO240A, B; 648049 654728 654861 4.4270-4.4280
IOF240B
IO360A, AB, C, CB, D, DB, ES, G, GB, N/A N/A 654861P015 4.4420-4.4430
H, HB, J, JB, K, KB
657989 5.2422-5.2432
657989P005 5.2472-5.2482
N/A N/A
657989P010 5.2522-5.2532
IO346A
TSIO550B, C, E, G, K, N TSIOF550D, J, 657989P015 5.2572-5.2582
K, P 649805 654731 5.2432-5.2442
TSIOL550A, B, C
649805P005 654731P005 5.2482-5.2492
N/A
649805P010 654731P010 5.2532-5.2542
649805P015 654731P015 5.2582-5.2592
LTSIO360E, EB, KB, RB 648048 654727 654859 4.4270-4.4280
TSIO360A, AB, C, CB, D, DB, E, EB, F,
FB, GB, H, HB, JB, KB, LB, MB, RB, SB N/A N/A 654859P015 4.4420-4.4430

646263 654744 654833 4.9907-4.9922

O470K, L, R, S, -4, -13, -13A
N/A N/A 654833P015 5.0057-5.0072
O470U 648029 654722 654832 4.9887-4.9897
IO470D, E, F, H, L, M, N, S, U, V, VO N/A N/A 654832P015 5.0037-5.0047
O470G, M, P
O470GCI, MCI 648028 654721 654829 4.9887-4.9897
IO470C, G, P, R
O470-7A, 7B, 11, 11CI, 15, A, E, J 649044 654729 654862 4.9887-4.9897
IO470J, K
E165, E185, E225 N/A N/A 654832P015 5.0037-5.0047

TSIO470B, C, D N/A N/A 655988 4.9887-4.9897

GTSIO520C, D, H, K, L, M, N 648044 654724 654840 5.2420-5.2430
TSIO520AF, B, BB, BE, C, CE, D, DB, E, 654840P010 5.2520-5.2530
EB, G, H, J, JB, K, KB, L, LB, M, N, NB, N/A N/A
P, R, T, UB, VB, WB 654840P015 5.2570-5.2580

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Table 10-25. Engine to Piston Cross Reference
NOTE: *Non-coated pistons (with untreated skirt or graphite treated
skirt) were discontinued in 1998 and are provided for reference only.

Non-coated Piston
Manganese
*graphite treated Phosphate Coated
Engine Model *untreated skirt skirt Piston Piston Diameter
648045 654850 5.2420-5.2430
IO520A, B, BA, BB, C, CB, D, E, F, J, K,
N/A 654850P010 5.2520-5.2530
L, M, MB, N, NB N/A
654850P015 5.2570-5.2580
IO520P 648037 654723 654836 5.2420-5.2430
LIO520P 654836P010 5.2520-5.2530
LTSIO520AE N/A N/A
TSIO520AE 654836P015 5.2570-5.2580
648046 654726 654857 5.2420-5.2430
IO550A, B, C, D, E, F, G, L, N, P, R
654857P010 5.2520-5.2530
IOF550B, C, D, E, F, L, N, P & R N/A N/A
654857P015 5.2570-5.2580

10-6.12. Legacy Product Replacement Valves

NOTE: Information contained in this section was originally published in
Service Bulletin M76-8.
Applicable Engines:
C-75, C-85, C-90, O-200 (except -D and -X), O-300 and GO-300
Applicable Engine Serial Numbers:
Table 10-26. Engines Serial Number Applicability
Engine Serial Numbers
Factory
Overhauled
Engine Model New Engine Rebuilt Engine Engine
O-200-A 2541781 6645-R 901140-0
O-300-A N/A2 16092-R 901146-0
O-300-C N/A 23223-R N/A
O-300-D N/A 25560-R N/A
C-90 N/A N/A 901169-0

1. It is possible that some O-200-A new engines prior to S/N 254178 were built incorporating 30° face intake
valves. When servicing any O-200-A engine cylinders, check the part number stamped on the cylinder base
flange before installing valves.
2. New engine production terminated prior to product improvement.
Many low compression engines, originally certified for operation with 80/87 fuel,
experience lead build-up or spark plug fouling as a result of the higher octane and lead
content of 100/100LL (Ref: Section 7-2.2). To improve intake valve service life,

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Continental introduced new intake valve designs in 1976. Design changes to the valve and
valve seat angle and a new valve seat material were incorporated in all new and rebuilt
engines manufactured after May 19, 1976. Aftermarket parts were made available to the
field after May 28, 1976.
The components listed in the third column of Table 10-27 were designed to improve
operation of low compression ratio engines with 100/100LL fuels. Further improvements
since 1976 required redesign of the original replacement parts with new part numbers. The
current replacement part numbers, as of the publication date of this document are listed in
the far right column. See Section 1-4 for more information regarding service parts.
Table 10-27. Replacement Components for Low Compression Ratio Cylinders
Original Current
Replacement Part Replacement Part
Engine Model Component Number Number
Intake Valve 639661 657512
A65, A75
Exhaust Valve 639662 655972
Intake Valve 641792 655968
GO-300 Intake Valve Seat 641793 655530
Exhaust Valve 631639 655969

C-75, C-85, C-90, C-125, C-145 Intake Valve 641792 655968

O-200, O-300 Intake Valve Seat 641793 655530

Intake valve, part number 531608 and the intake valve seat insert, part number 3912
installed in the above engine models prior to May 1976 are no longer available and, if
discovered during overhaul or cylinder inspection, should be removed and replaced with
the current part numbers, or subsequent replacement part numbers, regardless of the
condition of the installed valves and valve seats.
The improved valve design is commonly referred to as a “30° angle valve” indicating the
valve face is ground at a 30° offset angle from the surface of the head in the combustion
chamber; however the standard practice (see Figure 10-24) for design engineering is to
reference the valve face dimension off the valve stem centerline and the valve seat insert
off the valve guide centerline.
Table 10-28. Cylinder Part Number Conversion
Original Part Number New Part Number
A50222 641916
639702 641916
626710 641917
639703 641917

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After installation of the new valve and valve guide, the cylinder assembly will no longer
meet the specifications of the part number identified on the base flange. Cross out the
original part number on the base flange with a steel stamp letter “X” and stamp the
cylinder with the following part numbers adjacent to the previous part number:
Valve seats are sold unfinished. After installation, the valve seats must be ground, in
reference to the valve guide. Reference valve seat grinding instructions in the primary
ICA. Grind the new valve seats to the dimensions specified in Figure 10-24. The new
valve seat angle should be 60° +30’/-0. Valve seat width should be 0.060” wide, not to
exceed the maximum O.D. specified in the primary ICA. To narrow the width of the valve
seat after grinding, top off with a 75° stone, as depicted in Figure 10-24. Valve lapping,
according to instructions in the primary ICA is permitted to optimize the valve face and
valve seat mating surfaces.
CAUTION: All lapping compound must be removed from the valves,
valve seats and cylinder assembly before cylinder installation.
Make a log book entry indicating compliance with M76-8 and M-0.
CAUTION: Instructions in Figure 10-24 apply to rework of the
valves and valve guides in the subject cylinder assemblies discussed
in Section 10-6.12 only. Instructions are not standard for all intake
valves and valve guides.

Figure 10-24. Intake Valve Angle

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10-7. Crankcase Repair
WARNING
Weld repairs are NOT permitted in the critical (non-shaded)
areas of the crankcase or the bearing support structures. An
FAA-approved repair facility is the only facility authorized to
perform a crankcase weld repair.
Crankcase welding is not an in-service repair. The engine must be removed from the aircraft,
disassembled, and soaked in solvent to remove flammable material. Welding is only
permitted on non-critical areas of the crankcase identified in Figure 6-82 through Figure 6-
89. Only a Part 145 Repair Station, certified to perform crankcase welding may complete the
repair. The dimensional integrity of the crankcase must be maintained. Record crankcase
repair in the engine log book:
1. Engine total time in service
2. Method of inspection following repair (visual, dye penetrant, or other)
3. Identify location of crack repair area
4. Structural and dimensional characteristics of repaired crack
5. Date

10-8. Piston Replacement

CAUTION: The removal of metal from connecting rods, crankshafts
or pistons, for the purposes of balancing, is not an approved
procedure. Indiscriminate work of this type, accomplished without
the benefits of renitriding, shot peening and/or heat treatment can
seriously compromise the structural integrity of the engine.
NOTE: The allowable weight variation between connecting rods or
pistons does not apply to the entire set. Connecting rods and pistons
weight variations are limited to opposing cylinder bays. For four cylinder
engines, pistons in cylinders 1 and 2 must be matched within one half
ounce. Pistons in cylinders 3 and 4 must match the same criteria. For six
cylinder engines, the pistons in cylinders 5 and 6 must be matched within
one half ounce as well as the previously mentioned criteria for cylinders 1
through 4 in the four cylinder engines.
Pistons are selected in pairs with a maximum weight variation not to exceed 1/2 ounce in
opposing bays.

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10-9. Crankshaft Repair
WARNING
Crankshafts may only be repaired by an approved FAA Part
145 Repair Stations. Do not attempt crankshaft repair without
the required FAA certification.
CAUTION: Do not attempt to repair a scored or overheated
crankshaft. Discard and replace scored or scorched crankshafts.

If a crankshaft is repaired by an FAA Repair Station, the nitride
treatment must be restored.
Crankshaft overhaul repairs must be performed by an FAA Part 145 Repair Station
certified to perform crankshaft repair using methods approved by the Federal Aviation
Administration. The repaired crankshaft must meet the dimensional limits specified in the
primary Instructions for Continued Airworthiness.
1. Remove the crankshaft counterweights according to the instructions in Section 10-
9.1.1.
2. Identify the counterweight using the illustrations in Section 10-9.1.2. Inspect the
Counterweight assemblies according to the instructions in Section 10-9.1.3. Replace
Counterweight Bushings according to the instructions in Section 10-9.1.5.
3. Inspect the Hanger Blade Bushings according to the instructions in Section 10-9.1.6.
Replace Hanger Blade Bushings, as required, according to the instructions in
Section 10-9.1.5.
4. Install the Crankshaft Oil Control Plug according to the instructions in Section 10-9.2.
5. After the crankshaft hanger blade bushing replacement, counterweight replacement,
counterweight bushings replacement, or the oil control plug is replaced, perform a
“Magnetic Particle Inspection” on the crankshaft and counterweights and a “Crankshaft
Ultrasonic Inspection” to ensure no cracks developed during the bushing or plug
installation process.
10-9.1. Crankshaft Counterweight Inspection and Repair
This Section is divided in subsections, consisting of multiple tables listing the engine power
train major component part numbers (Table 10-29), parts supersedure (Table 10-33), and
repair instructions for crankshaft counterweights and connecting rods (Table 10-39).
Use Table 10-29 to locate the engine crankshaft part number and subsequent tables in this
section to determine the appropriate counterweight and connecting rod repair instructions.
To determine appropriate piston and piston rings to mate with the connecting rods, refer to
the Tables in Section 10-6.11.

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Table 10-29. Engine Power Train

Crankshaft Connecting Connecting Oil Control

Engine Model Assembly Rod 1 Rod Bearing Bearing Set Collar
A-65 530199A1 A35160A2 639640 627246A2 N/A
530058A6 2 N/A
A-75 530199A1 A35160A2 639640 627246A2 N/A
530058A6 2 N/A
C-75 530196A1 3 A35160A2 639640 530058A4 N/A
530199A1 4 530058A5 N/A
C-85 530196A1 3 A35160A2 639640 530058A4 N/A
530199A1 4 530058A5 N/A
C-90 530182 5 654795 639640 530058A4 N/A
530058A5 N/A
C-145-2 530860 654795 639640 530058A4 N/A
530058A5 N/A
C-145-2H 531113 654795 639649 652152A1 N/A
530058A5 N/A
E-165 352174A2 A36121 530383 646149A1 N/A
E-185-1, 3, 8, 9 537561 A36121 530383 646149A1 N/A
E-185-1, 3, 8, 9 352174 A36121 530383 646149A1 N/A
E-225-4, 8 537561 A36121 530383 646149A1 N/A
627246A2
O-200-A 653012 654795 639640 N/A
530058A6 2
627246A2
O-200-B 653012 654795 639640 N/A
530058A6 2
639640-UPPER 2
O-200-D & X 657466 654795 N/A
657564-LOWER 530058A7
O-240 637069 654794 639640 637062A2 N/A
O-300-A 530860 654795 639640 652152A1 N/A
O-300-B 531113 654795 639640 530516A2 N/A
O-300-C 653382 654795 639640 652152A1 N/A
O-300-D 653382 654795 639640 652152A1 N/A
O-470-2 No Longer Supported
O-470-4 No Longer Supported
O-470-7 No Longer Supported
O-470-11 No Longer Supported
O-470-13A No Longer Supported
O-470-15 No Longer Supported

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Table 10-29. Engine Power Train

Crankshaft Connecting Connecting Oil Control

Engine Model Assembly Rod 1 Rod Bearing Bearing Set Collar
537401A3 6
O-470-A 649141 655910 630826 646589A1 7 N/A
646590A1 8
537401A3 6
O-470-B 653697 655910 630826 N/A
646589A1 7
O-470-C 649141 655910 630826 537401A3 6 N/A
537401A3 6
O-470-E 649141 655910 630826 646589A1 7 N/A
646590A1 8
646591A3 8
646588A1 7
O-470-G 652005 655910 630826
646807A1 9 626739
627795A3 6 10
537401A3 6
O-470-J 649141 655910 630826 646589A1 7 N/A
646590A2 8
537401A3 6
O-470-K 652039 655910 630826 646589A1 7 N/A
646590A2 8
537401A3 6
O-470-L 652039 655910 630826 646589A1 7 N/A
646590A2 8
646807A1 6
O-470-M 652039 655910 630826 646589A1 7 N/A
646590A2 8
537401A3 6
O-470-N 653697 655910 630826 N/A
646589A1 7
646591A3 8
O-470-P 652011 655910 630826 646588A1 7
627795A3 6 9
537401A3 6
O-470-R 649141 655910 630826 646589A1 7 N/A
646590A2 8
646589A1 7
O-470-S 649141 655910 630826 N/A
646590A2 8

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Table 10-29. Engine Power Train

Crankshaft Connecting Connecting Oil Control

Engine Model Assembly Rod 1 Rod Bearing Bearing Set Collar
646589A1 7
O-470-U 649138 655910 630826 N/A
646590A2 8
GO-300-A, C, D, E 627822 654794A1 639640 626943A1 N/A
GTSIO-520-C 653020 655910 630826 633024A2 N/A
GTSIO-520-D 653020 655910 630826 633024A2 N/A
GTSIO-520-H 653020 655910 630826 633024A2 N/A
GTSIO-520-K 653020 655910 630826 633024A2 N/A
GTSIO-520-L 653020 655910 630826 633024A2 N/A
GTSIO-520-M 653020 655910 630826 633024A2 N/A
GTSIO-520-N 653020 655910 630826 633024A2 N/A
IO-240-A 653164 654793A1 642338 637062A3 N/A
IO-240-B 653164 654793A1 642338 637062A3 N/A
IOF-240-B 653164 654793A1 642338 637062A3 N/A
IO-346-A 630778 655910 630826 646594A1 N/A
IO-360-A 653138 654794A1 639640 646595A1 N/A
IO-360-AB 653129 654793A1 642338 646597A1 N/A
IO-360-AF 653129 654793A1 642338 646597A1 N/A
IO-360-C 653138 654794A1 639640 646595A1 N/A
IO-360-CB 653129 654793A1 642338 646597A1 N/A
IO-360-D 653138 654794A1 639640 646595A1 N/A
IO-360-DB 653129 654793A1 642338 646597A1 N/A
IO-360-ES 653129 654793A1 642338 646597A1 N/A
IO-360-G 653139 654794A1 639640 646595A1 N/A
IO-360-GB 653129 654793A1 642338 646597A1 N/A
IO-360-H 653139 654794A1 639640 646595A1 N/A
IO-360-HB 653129 654793A1 642338 646597A1 N/A
IO-360-J 653139 654794A1 639640 646595A1 N/A
IO-360-JB 653129 654793A1 642338 646597A1 N/A
IO-360-K 653139 654794A1 639640 646595A1 N/A
IO-360-KB 653129 654793A1 642338 646597A1 N/A
627795A3 6
IO-470-C 652011 655910 630826 646588A1 7 626739
646591A3 8
627795A3 6
IO-470-D 649133 655910 630826 646588A1 7 626739
646591A3 8

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Table 10-29. Engine Power Train

Crankshaft Connecting Connecting Oil Control

Engine Model Assembly Rod 1 Rod Bearing Bearing Set Collar
627795A3 6
IO-470-E 649133 655910 630826 646588A1 7 626739
646591A3 8
627795A3 6
IO-470-F 649133 655910 630826 646588A1 7 626739
646591A3 8
627795A3 6
IO-470-H 652011 655910 630826 646588A1 7 626739
646591A3 8
627795A3 6
IO-470-J 652009 655910 630826 646588A1 7 626739
646591A3 8
627795A3 6
IO-470-K 652009 655910 630826 646588A1 7 626739
646591A3 8
627795A3 6
IO-470-L 652010 655910 630826 646588A1 7 626739
646591A3 8
627795A3 6
IO-470-M 649133 655910 630826 646588A1 7 626739
646591A3 8
627795A3 6
IO-470-N 652011 655910 630826 646588A1 7 626739
646591A3 8
627795A3 6
IO-470-R 630977 A36121 530383 646588A1 7 626739
646591A3 8
627795A3 6
IO-470-S 649133 655910 630826 646588A1 7 626739
646591A3 8
627795A3 6
IO-470-U 649135 655910 630826 646588A1 7 626739
646591A3 8
627795A3 6
IO-470-V 649135 655910 630826 646588A1 7 626739
646591A3 8

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Table 10-29. Engine Power Train

Crankshaft Connecting Connecting Oil Control

Engine Model Assembly Rod 1 Rod Bearing Bearing Set Collar
646588A1 7
IO-520-A 649134 655910 630826 626739
646591A3 8
IO-520-B 649895 655910 630826 646593A2 629680
IO-520-BA 649896 655910 630826 646593A2 629680
IO-520-BB 649898 655911 642398 646592A2 629680
IO-520-C 649895 655910 630826 646593A2 629680
IO-520-CB 649898 655911 642398 646592A2 629680
646588A1 7
IO-520-D 649134 655910 630826 626739
646591A3 8
646588A1 7
IO-520-E 649134 655910 630826 626739
646591A3 8
646588A1 7
IO-520-F 649134 655910 630826 626739
646591A3 8
646588A1 7
IO-520-J 649134 655910 630826 626739
646591A3 8
646588A1 7
IO-520-K 649134 655910 630826 626739
646591A3 8
646588A1 7
IO-520-L 649134 655910 630826 626739
646591A3 8
IO-520-M 5 649895 655910 630826 646593A2 629680
IO-520-MB 649898 655911 642398 646592A2 629680
IO-520-P 649144-1 655910 630826 646593A2 629739
IO-550-A 649900 655911 642398 646592A2 629680
IO-550-B 649900 655911 642398 646592A2 629680
IO-550-B29B, 33B, 37B 649900 655912 642398 646592A2 629680
IO-550-C 649900 655911 642398 646592A2 629680
IO-550-C25B, 29B, 30B 649900 655912 642398 646592A2 629680
IO-550-D 646623 655911 642398 646592A2 626739
IO-550-E 646623 655911 642398 646592A2 626739
IO-550-F 646623 655911 642398 646592A2 626739
IO-550-G 649900 655911 642398 646592A2 629680
IO-550-L 646623 655911 642398 646592A2 626739
IO-550-N 649900 655911 642398 646592A2 629680
IO-550-P 649900 655911 642398 646592A2 629680
IO-550-R 649900 655911 642398 646592A2 629680
IOF-550-B, C 649900 655911 642398 646592A2 629680

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Table 10-29. Engine Power Train

Crankshaft Connecting Connecting Oil Control

Engine Model Assembly Rod 1 Rod Bearing Bearing Set Collar
IOF-550-D, E, F, L 646623 655911 642398 646592A2 626739
IOF-550-N, P, R 649900 655911 642398 646592A2 629680
LTSIO-360-E 653137 654794 639640 646596A1 N/A
LTSIO-360-EB 653136 654793 642338 646597A1 N/A
LTSIO-360-KB 653136 654793 642338 646597A1 N/A
LTSIO-360-RB 653136 654793 642338 646597A1 N/A
LTSIO-520-AE 649144-2 655000 630826 646591A4 626739
TSIO-360-A 653138 654794 639640 646595A1 N/A
TSIO-360-AB 653129 654793 642338 646597A1 N/A
TSIO-360-B 653138 654794 639640 646595A1 N/A
TSIO-360-C 653139 654794 639640 646595A1 N/A
TSIO-360-CB 653129 654793 642338 646597A1 N/A
TSIO-360-D 653139 654794 639640 646595A1 N/A
TSIO-360-DB 653129 654793 642338 646597A1 N/A
TSIO-360-E 653139 654794 639640 646595A1 N/A
TSIO-360-EB 653129 654793 642338 646597A1 N/A
TSIO-360-F 653139 654794 639640 646595A1 N/A
TSIO-360-FB 653129 654793 642338 646597A1 N/A
TSIO-360-G 653139 654794A1 639640 646595A1 N/A
TSIO-360-GB 653129 654793 642338 646597A1 N/A
TSIO-360-H 653139 654794 639640 646595A1 N/A
TSIO-360-HB 653129 654793 642338 646597A1 N/A
TSIO-360-JB 653129 654793 642338 646597A1 N/A
TSIO-360-KB 653129 654793 642338 646597A1 N/A
TSIO-360-MB 653129 654793 642338 646597A1 N/A
TSIO-360-RB 653129 654793 642338 646597A1 N/A
TSIO-360-SB 653129 654793 642338 646597A1 N/A
627795A3 6
TSIO-470-B 652011 646437A2 630826 626739
646588A1 7
627795A3 6
TSIO-470-C 652011 646437A2 630826 626739
646588A1 7
627795A3 6
TSIO-470-D 652011 646437A2 630826 626739
646588A1 7
TSIO-520-AE 649144-1 655000 630826 646591A4 626739
TSIO-520-AF 649134 655004 630826 646591A3 8 626739
TSIO-520-B 649895 655004 630826 646593A2 629680

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Table 10-29. Engine Power Train

Crankshaft Connecting Connecting Oil Control

Engine Model Assembly Rod 1 Rod Bearing Bearing Set Collar
TSIO-520-BB 649898 655005 642398 646592A2 629680
TSIO-520-BE 649898 655005 642398 646592A2 629680
646588A1 7
TSIO-520-C 649134 655004 630826 626739
646591A3 8
TSIO-520-CE 649148 655001 642398 646592A2 626739
TSIO-520-D 649895 655004 630826 646593A2 629680
TSIO-520-E 649895 655004 630826 646593A2 629680
TSIO-520-EB 649898 655005 642398 646592A2 629680
646588A1 7
TSIO-520-H 649134 655004 630826 626739
646591A3 8
TSIO-520-J 649895 655004 630826 646593A2 629680
TSIO-520-JB 649898 655005 642398 646592A2 629680
TSIO-520-K 649895 655004 630826 646593A2 629680
TSIO-520-KB 649898 655005 642398 646592A2 629680
TSIO-520-L 649895 655004 630826 646593A2 629680
TSIO-520-LB 649898 655005 642398 646592A2 629680
646588A1 7
TSIO-520-M 649134 655004 630826 626739
646591A3 8
TSIO-520-N 649895 655004 630826 646593A2 629680
TSIO-520-NB 649898 655005 642398 646592A2 629680
646588A1 7
TSIO-520-P 649134 655004 630826 626739
646591A3 8
646588A1 7
TSIO-520-R 649134 655004 630826 626739
646591A3 8
646588A1 7
TSIO-520-T 649134 655004 630826 626739
646591A3 8
TSIO-520-UB 649898 655005 642398 646592A2 629680
TSIO-520-VB 649898 655005 642398 646592A2 629680
TSIO-520-WB 649898 655005 642398 646592A2 629680
TSIO-550-A 649900 655001 642398 646592A2 629680
TSIO-550-B 649900 655001 642398 646592A2 629680
TSIO-550-C 649900 655001 642398 646592A2 629680
TSIO-550-G 649900 655001 642398 646592A2 629680
TSIO-550-K 649900 655001 642398 646592A2 629680
TSIO-550-N 649900 655001 642398 646592A2 629680
TSIOF-550-D 649900 655001 642398 646592A2 629680

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Table 10-29. Engine Power Train

Crankshaft Connecting Connecting Oil Control

Engine Model Assembly Rod 1 Rod Bearing Bearing Set Collar
TSIOF-550-J 649900 655001 642398 646592A2 629680
TSIOF-550-K 649900 655001 642398 646592A2 629680
TSIOL-550-A 652359 655001 642398 646592A2 629680
TSIOL-550-B 652359 655001 642398 646592A2 629680
TSIOL-550-C 652359 655001 642398 646592A2 629680
1. See Table 10-39 for new and old connecting rod part numbers and associate hardware usage
2. With 633141 thrust washer
3. Tapered crankshaft with removable prop flange
4. Propeller flange included with crankshaft forging
5. Non-production engine
6. Flange type bearing for use with Phase 1 style crankcase and crankshaft. See Service Bulletin M78-9 or latest revision.
7. Thrust washer type bearings for use with Phase 2 style crankcase and crankshaft. See Service Bulletin M78-9 or latest revision.
8. For use with Phase 3 style crankcase and crankshaft. See Service Bulletin M78-9 or latest revision.
9. For O-470-G engines with modernized crankshafts using oil transfer collar.
10. For O-470-G engines with modified crankshafts. Remove and discard nylon wipers for O-470-G

Table 10-30. Crankshaft Assembly Part Number History

Crankshaft
Specification Assembly Supersedes Supersedes Supersedes Supersedes
O-200-A 653012 531434
O-200-B 653012 531434
O-200-D & X 657466
O-300-A 530860
O-300-C 653382 1 652110 628124
O-300-D 653382 2 652110 628124
O-470-A 649141 633225 537290
O-470-B 653697 633227 539576
O-470-C 649141 633225 537290
O-470-E 649141 633225 537290
O-470-F 649141 633225 537290
O-470-G 652005 633256
O-470-J 649141 633225 537290
O-470-K 652039 633219 539665
O-470-L 652039 633219 539665
O-470-M 652039 633219 539665
O-470-N 653697 633227 539576
O-470-R 649141 633225 537290
O-470-S 649141 633225 537290
O-470-U 649138 643911 641905

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Table 10-30. Crankshaft Assembly Part Number History
Crankshaft
Specification Assembly Supersedes Supersedes Supersedes Supersedes
GO-300-A, C, D, E 627822
GIO-550-A3 652800A1
GTSIO-520-C 653020 652832 652821 652001 635104
GTSIO-520-D 653020 652832 652821 652001 635104
GTSIO-520-H 653020 652832 652821 652001 635104
GTSIO-520-K 653020 652832 652821 652001 635104
GTSIO-520-L 653020 652832 652821 652001 635104
GTSIO-520-M 653020 652832 652821 652001 635104
GTSIO-520-N 653020 652832 652821 652001 635104
IO-240-A 653164
IO-240-B 653164
IOF-240-B 653164
IO-346-A 630778
IO-360-A 653138 652047 649785 639200 634479
IO-360-AB 653129 652014 643627 642350
IO-360-AF 653129
IO-360-C 653138 652047 649785 639200 634479
IO-360-CB 653129 652014 643627 642350
IO-360-D 653138 652047 649785 639200 634479
IO-360-DB 653129 652014 643627 642350
IO-360-ES 653129
IO-360-G 653139 652048 639786
IO-360-GB 653129 652014 643627 642350
IO-360-H 653139 652048 639786
IO-360-HB 653129 652014 643627 642350
IO-360-J 653139 652048 639786
IO-360-JB 653129 652014 643627 642350
IO-360-K 653139 652048 639786
IO-360-KB 653129 652014 643627 642350
IO-470-C 652011 652006 633256 626784
IO-470-D 649133 630927 627530
IO-470-E 649133 630927 627530
IO-470-F 649133 630927 627530
IO-470-G 649133 630927 627530
IO-470-H 652011 652008 628995 630977 627348
IO-470-J 652009 643089 633246 628358
IO-470-K 652009 643089 633246 628358
IO-470-L 652010 643090 630886 628694

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Table 10-30. Crankshaft Assembly Part Number History
Crankshaft
Specification Assembly Supersedes Supersedes Supersedes Supersedes
IO-470-M 649133 630927 627530
IO-470-N 652011 652006 643091 630932 629309
IO-470-P 629882
IO-470-R 630977 629366
IO-470-S 649133 630927 627530
IO-470-U 649135 632195
IO-470-V 649135 632195
IO-520-A 649134 631716
IO-520-B 649895 633620
IO-520-BA 649896 639243
IO-520-BB 649898 646438 642396
IO-520-C 649895 633620
IO-520-CB 649898 646438 642396
IO-520-D 649134 631716
IO-520-E 649134 631716
IO-520-F 649134 631716
IO-520-J 649134 631716
IO-520-K 649134 631716
IO-520-L 649134 631716
IO-520-M 649895 633620
IO-520-MB 649898 646438 642396
IO-520-P 649144-1
IO-550-A 649900 646604
IO-550-B 649900 646604
IO-550-C 649900 646604
IO-550-D 646623
IO-550-E 646623
IO-550-F 646623
IO-550-G 649900
IO-550-L 646623
IO-550-N 649900
IO-550-P 649900
IO-550-R 649900
IOF-550-N 649900
IOF-550-P 649900
IOF-550-R 649900
LTSIO-360-E 653137 652045 641382
LTSIO-360-EB 653136 652015 643633
LTSIO-360-KB 653136 652015 643633

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Table 10-30. Crankshaft Assembly Part Number History
Crankshaft
Specification Assembly Supersedes Supersedes Supersedes Supersedes
LTSIO-360-RB 653136
LTSIO-520-AE 649144-2 643126-1
TSIO-360-A 653138 652047 649785 639200 634479
TSIO-360-AB 653129 652014 643627 642350
TSIO-360-B 653138 652047 649785 639200 634479
TSIO-360-C 653139 652048 639786
TSIO-360-CB 653129 652014 643627 642350
TSIO-360-D 653139 652048 639786
TSIO-360-DB 653129 652014 643627 642350
TSIO-360-E 653139 652048 639786
TSIO-360-EB 653129 652015 643633 642376
TSIO-360-F 653139 652048 639786
TSIO-360-FB 653129 652014 643627 642350
TSIO-360-G 653139 652048 639786
TSIO-360-GB 653129 652014 643627 642350
TSIO-360-H 653139 652048 639786
TSIO-360-HB 653129 652014 643627 642350
TSIO-360-JB 653129 652014 643627 642350
TSIO-360-KB 653129 652015 643633 642376
TSIO-360-LB 653129 652014 643627 642350
TSIO-360-MB 653129 652014 643627
TSIO-360-RB 653129
TSIO-360-SB 653129
TSIO-470-B 652011 652008 628995
TSIO-470-C 652011 652008 628995
TSIO-470-D 652348 652007 632494
TSIO-520-AE 649144-1 643126
TSIO-520-AF 649134 631716
TSIO-520-B 649895 633620
TSIO-520-BB 649898 646438 642396
TSIO-520-BE 649898 646438 642396
TSIO-520-C 649134 631716
TSIO-520-CE 649148 646683
TSIO-520-D 649895 633620
TSIO-520-E 649895 633620
TSIO-520-EB 649898 646438 642396
TSIO-520-G 649134 631716
TSIO-520-H 649134 631716
TSIO-520-J 649895 633620

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Table 10-30. Crankshaft Assembly Part Number History
Crankshaft
Specification Assembly Supersedes Supersedes Supersedes Supersedes
TSIO-520-T 649134 631716
TSIO-520-UB 649898 646438 642396
TSIO-520-VB 649898 646438 642396
TSIO-520-WB 649898 646438 642396
TSIO-550-A 649900
TSIO-550-B 649900
TSIO-550-C 649900
TSIO-550-E 649900
TSIO-550-G 649900
TSIO-550-K 649900
TSIO-550-N 649900
TSIOF-550-D 649900
TSIOF-550-J 649900
TSIOF-550-K 649900
TSIOL-550-A 652359
TSIOL-550-B 652359
TSIOL-550-C 652359
1. Part No. 653382 Crankshaft, Part No. 656081 Gear and four each Part No. 654584 bolts must be used together
2. Part No. 653382 Crankshaft, Part No. 630690 Gear and four each Part No. 654584 bolts must be used together
3. Not a production engine

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Table 10-31. Crankshaft Assemblies
Hanger
Blade
Bushing BUSH CWT CWT BUSH Cheek PIN CWT. RET RET
C/S Assy 1 I.D. Qty C/S CWT Bushing I.D. LOC. CWT. PIN DIA. ORDER Plate RING
531015 .4613 1 531017 531016 .4613 2
5
.4643 .4643 2 .3758
530860 630261-15 .3768
530868 402805-3
530863 .435 1 530864 530866 .435 2 6
.438 .438
531015 .4613 1 531017 531016 .4613 2
5
.4643 .4643 .3758
531113 630261-15 2 .3768 530868 402805-3
530863 .435 1 530864 530866 .435 2 6
.438 .438
2 2 3
.732 .732 .491
627822 626566 .739
2 627821 626564 .739
5 632261-11 2 .492
3 633976 629004
2 8 3
531015 .4613 1 531017 531016 .4613 2 5
.4643 .4643 .3758
628124 630261-15 2 .3768
530868 402805-3
530863 .435 1 530864 530866 .435 2 6
.438 .438
2 639195 2 643626-105 .565 6
.566

646623 350998
.622 1 639196 639193
.622 5 643626-103 .474 4 643629 629104
.626 .626 .475
1 639196 5 643626-104 .527 5
.528
.622 2 .622 2 .556 6
649133 350998 .626
639195 639193 .626
643626-101 .557 643629 629104
2 5 6
2 639195 2 643626-101 .556 6
.557

649134 350998
.622 1 639196 639193
622 5 643626-103 .474 4 643629 629104
.626 .626 .475
1 639196 5 643626-104 .527 5
.528
2 639195 2 643626-101 .556 6
.557

639135 350998
.622 1 639196 639193
622 5 643626-104 .527 5 643629 629104
.626 .626 .528
1 639196 5 643626-106 .507 4.5
.508
2 639195 2 643626-101 .556 6
.557

649138 350998
.622 1 639195 639193
622 5 643626-104 .527 5 643629 629104
.626 .626 .528
1 639195 5 643626-106 .507 4.5
.508
1 2 643626-101
.556 6
.622 .622 .557
649141 350998 .626
639195 639193 .626
643629 629104
1 2 643626-104 .527 5
.528

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Table 10-31. Crankshaft Assemblies
Hanger
Blade
Bushing BUSH CWT CWT BUSH Cheek PIN CWT. RET RET
1
C/S Assy I.D. Qty C/S CWT Bushing I.D. LOC. CWT. PIN DIA. ORDER Plate RING
1 2 643626-104
.527 5
.622 .622 .528
649144-1 350998 .626
639195 639193 .626
643629 629104
1 2 643626-105 .565 6
.566
1 2 643626-104
.527 5
.622 .622 .528
649144-2 350998 .626
639195 639193 .626
643629 629104
1 2 643626-105 .565 6
.566
2 639195 2 643626-105 .565 6
.566

639148 350998
.622 1 639196 639193
.622 5 643626-103 .474 4 643629 629104
.626 .626 .475
1 639196 5 643626-104 .527 5
.528
2 639195 2 643626-101 .556 6
.557

649895 350998
.622 1 639196 639193
.622 5 643626-103 .474 4 643629 629104
.626 .626 .475
1 639196 5 643626-104 .527 5
.528
2 639195 2 643626-101 .556 6
.557

649896 350998
.622 1 639196 639193
.622 5 643626-101 .556 6 643629 629104
.626 .626 .557
1 639196 5 643626-103 .474 4
.475
2 639195 2 643626-105 .565 6
.566

649898 350998
.622 1 639196 639193
.622 5 643626-103 .474 4 643629 629104
.626 .626 .475
1 639196 5 643626-104 .527 5
.528
2 639195 2 643626-105 .565 6
.566

649900 350998
.622 1 639196 639193
.622 5 643626-103 .474 4 643629 629104
.626 .626 .475
1 639196 5 643626-104 .527 5
.528
1 639197 2 643626-105 .565 6
.622 .622 .566
652005 350998 .626
639193 .626
643629 629104
1 639197 2 643626-108 .594 4
.595
1 639195 2 643626-101 .556 6
.622 .622 .557
652009 350998 .626
639193 .626
643629 629104
1 639195 2 643626-104 .527 5
.528

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Table 10-31. Crankshaft Assemblies
Hanger
Blade
Bushing BUSH CWT CWT BUSH Cheek PIN CWT. RET RET
1
C/S Assy I.D. Qty C/S CWT Bushing I.D. LOC. CWT. PIN DIA. ORDER Plate RING
2 639195 2 643626-101 .556 6
.622 .622 .557
652010 350998 .626
639193 .626
643629 629104
2 639195 5 643626-104 .527 5
.528
2 639195 2 643626-101 .556 6
.622 .622 .557
652011 350998 .626
639193 .626
643629 629104
2 639195 5 643626-101 .556 6
.557
2 639195 2 643626-101 .556 6
.622 .622 .557
652039 350998 .626
639193 .626
643629 629104
2 639195 5 643626-101 .556 6
.557
2 639195 2 643626-101 .565 6
.566

652348 350998
.622 1 639196 639193
.622 5 643626-103 .474 4 643629 629104
.626 .626 .475
1 639196 5 643626-104 .527 5
.528
2 639195 2 643626-105 .565 6
.566

652359 350998
.622 1 639196 639193
.622 5 643626-103 .474 4 643629 629104
.626 .626 .475
1 639196 5 643626-106 .507 4.5
.508
2 2 643626-104 .527 3
.528

653020 658975
.754 2 652833 628978
.754 5 643626-104 .527 3 631808 629004
.757 .757 .528
2 8 643626-104 .527 3
.528
1 639199 2 643626-110 .498 4.5
.604 .604 .499
653129 639580 .607
639198 .607
653143 629004
1 639199 2 643626-111 .552 6
.553
1 639199 2 643626-110 .498 4.5
.604 .604 .499
653136 639580 .607
639198 .607
653143 629004
1 639199 2 643626-111 .552 6
.553
1 639199 2 643626-110 .498 4.5
.604 .604 .499
653137 639580 .607
639198 .607
653143 629004
1 639199 2 643626-111 .552 6
.553
1 639199 2 643626-109 .545 6
.604 .604 .546
653138 639580 .607
639198 .607
653143 629004
1 639199 2 643626-109 .545 6
.546

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Table 10-31. Crankshaft Assemblies
Hanger
Blade
Bushing BUSH CWT CWT BUSH Cheek PIN CWT. RET RET
1
C/S Assy I.D. Qty C/S CWT Bushing I.D. LOC. CWT. PIN DIA. ORDER Plate RING
1 639199 2 643626-110 .498 4.5
.604 .604 .499
653139 639580 .607
639198 .607
653143 629004
1 639199 2 643626-111 .552 6
.553
1 639199 2 643626-112 .520 5
.604 .604 .521
653382 639580 .607
639198 .607
653143 629004
1 639199 2 643626-112 .520 5
.521
2 639195 2 643626-105 .565 6
.622 .622 .566
653697 350998 .626
639193 .626
643629 629104
2 639195 5 643626-105 .565 6
.566
2 2 643626-104 .527 3
.528
652800A1 .754 2 .754 5 643626-104 .527 3
3 628975 .757
652833 628978 .757 .528
631808 629004
2 8 643626-104 .527 3
.528
1 639195 2 643626-105 .565 6
654359 .622 .622 .566
3
350998 .626
639193 .626
643629 629104
1 639195 2 643626-105 .565 6
.566

1. Replacement Crankshaft hanger blade bushings may be purchased in standard and oversize dimensions as listed in Table 10-32
2. If replacing Part No. 630261 pin with Part No. 643626 pin, the Part No. 643629 plate must be used
3. Used in non-production engines only

Table 10-32. Crankshaft Hanger Blade Bushing Sizes

Crankshaft Blade
Bushing Part No. STANDARD P 0.0015 P 0.003 P 0.005 P 0.010 P 0.015
350998 AVAILABLE AVAILABLE AVAILABLE AVAILABLE AVAILABLE AVAILABLE
530863 AVAILABLE N/A AVAILABLE AVAILABLE N/A N/A
531015 AVAILABLE N/A N/A N/A N/A N/A
537038 AVAILABLE N/A N/A N/A N/A N/A
626566 AVAILABLE N/A N/A AVAILABLE N/A N/A
628975 AVAILABLE N/A AVAILABLE AVAILABLE AVAILABLE N/A
639580 AVAILABLE AVAILABLE AVAILABLE AVAILABLE AVAILABLE AVAILABLE

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Table 10-33. Wide Rod Crankshaft
(NOT CURRENT PRODUCTION)

Hanger CWT RET RET

Blade BUSH CWT C/S CWT Bushing BUSH Cheek CWT. PIN PIN CWT. PLATE RING
1 2 3 4 5
C/S Assy Bushing I.D. Qty I.D. LOC. DIA. ORDER
352174 .622 .622 .5554
(E-185-1, 3, 350996 .626
2 352117 350977 .626
2 630261-4 .5574
6 352115 352116
8, 9, 11)
537661 350998
.622
1 352117 350997
.622
2 630261-4
.5554
6 352115 352116
(E-185-1, 3, .626 .626 .5574
8, 9, 11 & .6534 .6534 .5554
E-225-4, 8) 537038 .6554
1 537049 537044 .6554
2 630261-4 .5574
5 352115 352116
537290 350998
.622
1 352117 350997
.622
2 630261-4
.5554
6 352115 352116
(O-470-A, .626 .626 .5574
C, E, F, J & .6534 .6534 .5554
R) 537038 .6554
1 537049 537044 .6554
2 630261-4 .5574
5 352115 352116
.622 .622 .5652
539576 350998 .626
1 352117 350997 .626
2 630261-2 .5662
6 352115 352116
(O-470-B &
.6534 .6534 .5947
N) 537038 .6554
1 537049 537044 .6554
2 630261-1 .5967
6 352115 352116
.622 .622 .5931
350998 .626
1 352117 350997 .626
2 630261-5 .5951
9 352115 352116
627576
(O-470-G) .6534 .6483 .5931
537038 .6554
1 625818 625817 .6523
2 630261-5 .5951
6 352115 352116
.622 .622 .5554
539665 350998 .626
2 352117 350997 .626
2 630261-4 .5574
6 352115 352116
(O-470-K,
.622 .622 .5554
L, M) 350998 .626
2 352117 350997 .626
5 630261-4 .5574
6 352115 352116
.622 .622 .5554
350998 .626
2 352117 350997 .626
2 630261-4 .5574
6 352115 352116
627587
(O-470-P) .622 .622 .5554
350998 .626
2 352117 350997 .626
5 630261-4 .5574
6 352115 352116
.622 .622 .5554
350998 .626
2 352117 350997 .626
2 630261-4 .5574
6 352115 352116
626784
(IO-470-C) .622 .622 .5554
350998 .626
2 352117 350997 .626
5 630261-4 .5574
6 352115 352116

627530 .622 .622 .5554

350998 .626
2 352117 350997 .626
2 630261-4 .5574
6 352115 352116
(IO-470-D,
E, F, G, M & .622 .622 .5554
S) 350998 .626
2 352117 350997 .626
5 630261-4 .5574
6 352115 352116
.622 .622 .5554
350998 .626
2 352117 350997 .626
2 630261-4 .5574
6 352115 352116
627348
(IO-470-H) .622 .622 .5554
350998 .626
2 352117 350997 .626
5 630261-4 .5574
6 352115 352116
.622 .622 .5554
350998 .626
2 352117 350997 .626
2 630261-4 .5574
6 352115 352116
629366
(IO-470-R) .622 .622 .5554
350998 .626
2 352117 350997 .626
5 630261-4 .5574
6 352115 352116

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Table 10-33. Wide Rod Crankshaft
(NOT CURRENT PRODUCTION)
Hanger CWT RET RET
Blade BUSH CWT C/S CWT Bushing BUSH Cheek CWT. PIN PIN CWT. PLATE RING
1 2 3 4 5
C/S Assy Bushing I.D. Qty I.D. LOC. DIA. ORDER
.622 .622 .5554
629882 350998 .626
1 352117 350997 .626
2 630261-2 .5574
6 352115 352116
(IO-470-P,
.622 .622 .5554
T) 350998 .626
1 352117 350997 .626
2 630261-2 .5574
6 352115 352116
.622 .622 .5554
628358 350998 .626
1 352117 350997 .626
2 630261-4 .5574
6 352115 352116
(IO-470-J,
.6534 .6534 .5554
K) 537038 .6554
1 537049 537044 .6554
2 630261-4 .5574
5 352115 352116
.622 .622 .5554
350998 .626
2 352117 350997 .626
2 630261-4 .5574
6 352115 352116
628694
(IO-470-L) .6534 .6534 .527
350998 .6554
2 352117 350997 .6554
5 630261-3 .528
5 352115 352116
.622 .622 .5554
350998 .626
2 352117 350997 .626
2 630261-4 .5574
6 352115 352116
629309
(IO-470-N) .6534 .6534 .5554
350998 .6554
2 352117 350997 .6554
5 630261-4 .5574
6 352115 352116
632195 350998
.622
2 352117 350997
.622
2 630261-4
.622 6
(IO-470-U .626 .626 .626
& V) .622 .622 .622 5
350998 .626
1 631968 350997 .626
5 630261-3 .626
352115 352116

350998
.622
1 631968 350997
.622
5 630261-32
.622 4.5
.626 .626 .626

1. Counterweight Part No. 352117 superseded by Part No. 639195;

Counterweight Part No. 537049 superseded by Part No. 639205; 
Counterweight Part No. 639205 superseded by Part No. 639205A1;
Counterweight Part No. 625818 superseded by Part No. 639210; 
Counterweight Part No. 639210 superseded by Part No. 639210A1
2. Bushing Part No. 350997 superseded by Part No. 639193;
Bushing Part No. 537044 superseded by Part No. 639204
3. Counterweight Supersedure (See Table 10-34 for details): 
When using Part No. 630261-x pins, Part No. 635623 retainer plates must be used
When using Part No. 643626-x pins, Part No. 643629 retainer plates must be used
4. Plate Part No. 352115 superseded by Part No. 629105; 
Plate Part No. 629105 superseded by Part No. 635623; 
Plate Part No. 635623 superseded by Part No. 643629
5. Retaining Ring Part No. 352116 superseded by Part No. 629104

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Table 10-34. Counterweight Supersedure

Superseded Part
Current Part No. Pin Diameter No. Pin Diameter Original Part No. Pin Diameter
643626-101 0.556 - 0.557 630261-35 0.5559 - 0.5569 630261-4 0.554 - 0.5574
643626-103 0.474 - 0.475 630261-38 0.474 - 0.475 630261-27 0.474 - 0.475
643626-104 0.527 - 0.528 630261-37 0.527 - 0.528 630261-3 0.527 - 0.528
643626-105 0.565 - 0.566 630261-40 0.5652 - 0.5662 630261-2 0.5652 - 0.5662
643626-106 0.507 - 0.508 630261-39 0.507 - 0.508 630261-32 0.507 - 0.508
643626-107 0.490 - 0.491 630261-34 0.4902 - 0.4906 N/A N/A
643626-108 0.594 - 0.595 630261-36 0.5931 - 0.5951 630261-5 0.5931 - 0.5951
643626-109 0.545 - 0.546 630261-41 0.545 - 0.546 N/A N/A
643626-110 0.498 - 0.499 630261-43 0.498 - 0.499 N/A N/A
643626-111 0.552 - 0.553 630261-44 0.552 - 0.553 N/A N/A
643626-112 0.520 - 0.521 N/A N/A N/A N/A
N/A N/A N/A N/A 630261-11 0.4916 - 0.4921
N/A N/A N/A N/A 630261-15 0.3758 - 0.3768
N/A N/A N/A N/A 630261-17 0.6700 - 0.6710

10-9.1.1. Crankshaft Counterweight Removal

1. Remove the counterweight retaining rings (snap rings) from the counterweight bores
using Inside snap ring pliers with a 90 degree bend.
2. Remove the counterweight pin retaining plates from the bores. The plates are a close
tolerance fit and may require slight rocking to remove them.
3. Remove the counterweight pins with a magnet.
CAUTION: Retaining rings are single use; discard immediately
upon removal.
4. Discard the retaining plates and retaining rings.

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10-9.1.2. Counterweight Identification
Counterweights dimensions are illustrated in Figure 10-25 through Figure 10-33.

Figure 10-25. Part No. 530864 Counterweight Assembly

(made with 530865 Counterweight and 530866 Bushings)

Figure 10-26. Part No. 531017 Counterweight Assembly

(made with 530865 Counterweight and 531016 Bushings)

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Figure 10-27. Part No. 639196 Counterweight Assembly

(made with 631903 Counterweight and 639193 Bushings)

Figure 10-28. Part No. 639197 Counterweight Assembly

(made with 633339 Counterweight and 639193 Bushings)

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Figure 10-29. Part No. 639195 Counterweight Assembly

(made with 351000 Counterweight and 639193 Bushings)

Figure 10-30. Part No. 639199 Counterweight Assembly

(made with 629693 Counterweight and 639198 Bushings)

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Figure 10-31. Part No. 652833 Counterweight Assembly

(made with 652834 Counterweight and 628978 Bushings)

Figure 10-32. Part No. 627821 Counterweight Assembly

(made with 626688 Counterweight and 626564 Bushings)

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Figure 10-33. Part No. 639205 and 639210 Counterweight Assemblies

(made with 35100 Counterweight)
(639205 Counterweight uses 639204 Bushings)
(639210 Counterweight uses 639209 Bushings)

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10-9.1.3. Crankshaft Counterweight Inspection
CAUTION: Only the case hardened (tuftrided) counterweight
assemblies P/N 639195, 639196, 639197, 639199, 639205, or later
design and 627821, 530864, 531017 (non-tuftrided) counterweight
assemblies may be considered for bushing replacement. Discard all
other earlier design counterweights.
CAUTION: On GTSIO-520 engine models, ALL Part No. 631810
counterweights must be replaced with 652833, or later design
counterweights. Scrap all 631810 counterweights upon removal.
Equipment required
• 4% copper sulfate (CuSO4) and water solution (by volume)
• Borroughs Part No. 8077C, Counterweight Bushing Removal/Installation Fixture
(Section 2-1), or equivalent
• Two matched V-blocks
1. Inspect the crankshaft counterweight bump surface as shown in Figure 10-34; bump
surface contact marks must not exceed 0.005 inches in depth.
2. Remove and discard the counterweight bushings using the Counterweight Bushing
Removal/Installation Fixture 8077C or equivalent.
3. Thoroughly clean the counterweight bushing bore.
4. Verify tuftriding is present on the counterweight assemblies by placing one drop of a
4% copper sulfate (CuSO4) and water solution (by volume) on the cleaned surface of
the counterweight bushing bore.
5. Allow at least 15 seconds for the chemical reaction to take place.
6. Formation of red deposits indicates the absence of tuftriding. Discard any
counterweight that does not exhibit tuftriding and replace with new counterweights.
7. If no reaction occurs, wipe off copper sulfate and water solution. The counterweight
may be reused during overhaul, provided it meets all other inspection criteria.
8. Perform a “Magnetic Particle Inspection” on the crankshaft and counterweights
according to the instructions in Section 11-3.

INSPECT THIS
BUMP SURFACE AREA

Figure 10-34. Crankshaft Counterweight Bump Service Inspection

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10-9.1.4. Crankshaft Counterweight Bushing Bore Inspection
Equipment required
• Federal Dimension Air Gauge (with appropriate setting ring and air plug) or
• Starrett No. 78 series 3-point contact inside micrometer (Section 2-1)
1. Verify the counterweight bushing bores are smooth. Discard counterweights with worn,
pitted, fretted or out-of-round bushing bores.
2. Use a Federal Dimension Air Gauge (with appropriate setting ring and air plug) or
Starrett No. 78 series 3-point contact inside micrometer to measure the bushing bores.
Compare the bushing bores specified total indicator reading (T.I.R.) to the
specifications in Table 10-35. Discard counterweights with bushing bores exceeding
the specified dimensions.
3. Carefully inspect the counterweight counterbores for signs of wear in the wall that
retains the counterweight pin retaining plates. This area is adjacent to the inside edge of
the retaining ring groove. It may appear as an additional step and/or taper of the hole
into the retaining ring groove. Discard any counterweight that is:
a. Cracked
b. Worn, pitted, fretted, or out of round bushing bores
c. Worn or has distortions in the retaining ring groove that can affect the retaining
ring seating
4. If no plate wear is evident, check the retaining ring groove in each hole for wear
patterns that can affect the retaining ring seating. Any worn condition that may affect
retaining ring seating will require replacement of the counterweight.
5. Crankshaft counterweights are matched in pairs with a maximum weight variation of
two grams. If either counterweight is damaged, replace the counterweights as a
matched pair.

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Figure 10-35. Counterweight Bushing Bore Inspection

Table 10-35. Counterweight Bushing Bore Dimensions

“A” Diameter
Counterweight Assembly Part No. Counterweight Part No. See Figure 10-35
530864 530865 0.687 - 0.688
531017 530865 0.687 - 0.688
627821 626688 1.000 - 1.001
639195
639205 351000 0.8745 - 0.8755
639210
639196 631903 0.8745 - 0.8755
639197 633339 0.8745 - 0.8755
639199 629693 1.000 - 1.001
652833 652834 1.000 - 1.001

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10-9.1.5. Crankshaft Counterweight Bushing Replacement
Replace all crankshaft counterweight bushings at overhaul:
Equipment Required
• Borroughs Part No. 8077C Counterweight Bushing Removal/Installation Fixture, or
equivalent
• Federal Dimension Air Gauge (with appropriate setting ring and air plug) or
• Starrett No. 78 series 3 point contact inside micrometers
• Snap ring pliers (with 90-degree bend)
• Arbor press
The complete crankshaft /counterweight assembly is dynamically balanced and the
counterweights are matched in pairs with a maximum weight variation of two grams. If
either counterweight is damaged, both counterweights in the matched pair must be
replaced as a pair on that crankshaft cheek, even if only one counterweight is
unserviceable.
WARNING
Removing the counterweight bushings with makeshift tools
may cause irreparable damage which could lead to engine
malfunction.
1. Remove the crankshaft counterweight bushings with a Borroughs Part No. 8077C
Counterweight Bushing Removal/Installation Fixture and an arbor press.
2. Measure the crankshaft counterweight bushing bore inside diameter. Bushing bores
must be smooth and cylindrical (no out of round). Replacement bushings require an
interference fit of 0.0015 to 0.003 inches in the bushing bores.
3. Visually inspect the counterweights to determine acceptability of parts. Replace
counterweights with worn, pitted, fretted or out-of-round bushing bores.
WARNING
Counterweight bushings and bushing retainer plates (except as
indicated in Figure 10-37) require an interference fit. Replace
counterweight bushings (or counterweights) if insertion in the
bushing bore is possible without resistance.
4. Inspect counterweight bores/counterbores for signs of wear in the wall that retains the
counterweight pin retaining plates (area adjacent to the inside edge of the retaining
groove; it may appear as a taper of the hole into the retaining ring groove). If any wear
is evident, discard and replace the counterweight.
NOTE: Replace both counterweights in the matched pair even if only one
counterweight is unacceptable.
5. If the counterweight conforms to specification, check the counterweight retaining ring
groove for distortions in width, roundness or pattern which can affect the seating of the
retaining ring. Discard and replace the counterweight matched pair if wear or
distortions are found even on one counterweight.

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6. Install new bushings in the same positions as the old bushings on the counterweight
assemblies (Figure 10-36) using the Borroughs Part No. 8077C Counterweight
Bushing Removal/Installation Fixture. The bushing lead-in (Figure 10-36) must be
positioned toward the counterweight during installation. Press the bushing flush with
the surfaces as illustrated.

PRESS BUSHINGS FLUSH

INSTALL RETAINING RINGS TOWARD THE CAUTION: MINIMUM GAP WITH THESE SURFACES
CRANKSHAFT CENTERLINE AS SHOWN BETWEEN RETAINING RING EARS
= 0.179 INCH INSTALLED

INSTALL RETAINING RINGS WITH SHARP

EDGE (FLAT SURFACE) FACING OUTBOARD

Figure 10-36. Counterweight Inspection, Repair and Installation

Applicable to 360, 470, IO520, LTSIO-520, and 550 Series Engines
Not Applicable to GTSIO-520 (See Figure 10-37)
7. Verify newly installed bushing dimensions in Table 10-36. Close tolerances require
replacement bushings shall be 100% dimensionally inspected using calibrated, accurate
measuring equipment (one of the following):
a. Federal Dimension Air Gauge (with appropriate setting ring and air plug)
b. Starrett No. 78 series 3 point contact inside micrometers.

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8. Perform a “Magnetic Particle Inspection” according to the instructions in Section 11-3
on the crankshaft counterweight assembly to ensure the counterweight is free of cracks.

Table 10-36. Counterweight Bushing Bore Dimensions

“A” Diameter
Counterweight Assembly Part No. See Figure 10-36 & Figure 10-37
530864 0.435 - 0.438
531017 0.4613 - 0.4643
639195 0.622 - 0.626
639196 0.622 - 0.626
639197 0.622 - 0.626
639199 0.604 - 0.607
639205 0.6514 - 0.6554
639210 0.6483 - 0.6523
652833 0.754 -0.757
627821 0.732 -0.739

Figure 10-37. GTSIO-520 Counterweight Inspection, Repair and Installation

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10-9.1.6. Crankshaft Hanger Blade Bushing Inspection
Crankshaft hanger blade bushings (also referred to as damper bushings) must meet
dimensional specifications in Table 10-37. If the hanger blade bushing exhibits gouges or
scratches, is loose, or is otherwise unserviceable, replace the hanger blade bushing:
Equipment Required
• Borroughs Part No. 8077A Crankshaft Hanger Blade Bushing Removal/Installation
Tool, or equivalent
• Federal Dimension Air Gauge (with appropriate setting ring and air plug) or 
Starrett No. 78 series 3 point contact inside micrometers
WARNING
Removing or installing crankshaft counterweight bushings with
makeshift tools may cause irreparable damage to the
crankshaft that could lead to engine malfunction.
1. The bushing bores must be smooth and cylindrical (no out of round). Replacement
bushings require an interference fit of 0.0015 to 0.003 inches in the bushing bores.
2. Install the new crankshaft hanger blade bushings per Figure 10-38 using the Borroughs
Part No. 8077A Crankshaft Hanger Blade Bushing Removal/Installation Tool.
NOTE: New bushings must be installed into the same positions as the
original. Replacement crankshaft hanger blade bushings are available in
standard and some oversize dimensions.
3. Review Table 10-37 and Figure 10-38 to determine acceptability of parts.
4. Verify the dimensions of the newly installed bushings. Close tolerances require
replacement bushings be 100% dimensionally inspected using calibrated, accurate
measuring equipment (one of the following):
a. Federal Dimension Air Gauge (with appropriate setting ring and air plug)
b. Starrett No. 78 series 3 point contact inside micrometers.
5. Perform a “Magnetic Particle Inspection” according to the instructions in Section 11-3
on the crankshaft assembly after bushing installation to ensure no cracks developed as a
result of bushing installation and the crankshaft is free of cracks.

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Figure 10-38. Crankshaft Hanger Blade Bushing Replacement

Table 10-37. Counterweight Hanger Blade Bushing Dimensions

Crankshaft Installed Crankshaft Installed
Assembly Part Crankshaft Part Diameter “A” Assembly Part Crankshaft Part Diameter “A”
No. No. See Figure 10-38 No. No. See Figure 10-38
530860 5307891 0.4613 - 0.4643 652010 652004 0.622 - 0.626
646623 643687 0.622 - 0.626 652011 652004 0.622 - 0.626
649133 649132 0.622 - 0.626 652039 649137 0.622 - 0.626
649134 649132 0.622 - 0.626 652348 652004 0.622 - 0.626
649135 649132 0.622 - 0.626 652359 649899 0.622 - 0.626
649138 649137 0.622 - 0.626 653020 653019 0.754 - 0.756
649141 649137 0.622 - 0.626 653129 652012 0.604 - 0.607
649144-1 649143 0.622 - 0.626 653136 652013 0.604 - 0.607
649144-2 649146 0.622 - 0.626 653137 652044 0.604 - 0.607
649148 649147 0.622 - 0.626 653138 652046 0.604 - 0.607
649895 649894 0.622 - 0.626 653139 652046 0.604 - 0.607
649896 649894 0.622 - 0.626 653382 653383 0.604 - 0.607
649898 649897 0.622 - 0.626 653697 649137 0.622 - 0.756
649900 649899 0.622 - 0.626 652800 6494742 0.754 - 0.626
652005 652004 0.622 - 0.626 654359 643687 0.622 - 0.626
652009 652004 0.622 - 0.626
Install flush to below surface unless otherwise specified.
1. Part No. 530789 installs flush to 0.015 - 0.005 below surface
2. Part No. 649474 installs flush to 0.005 below surface

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10-9.2. Oil Control Plug Replacement
• Oil Plug Leak Test Fixture (Figure 2-12)
• Oil Control Plug Installation Tool (Figure 2-8 through Figure 2-11)
(differs by engine model)
NOTE: The 2.375-inch diameter collar at the rear of the Oil Control Plug
Installation Tool prevents driving the oil control plug beyond the
specified depth in the crankshaft. Do not use makeshift tools to install the
oil control plug.
1. Remove the crankshaft oil control plug using a 0.4375-20 diameter bolt approximately
8 inches long with 0.4375 -20NF threads and a slide hammer.
2. Inspect the inside diameter of the crankshaft for rust or pitting. Discard crankshafts
exhibiting rust or pitting. Clean the bore of the crankshaft using a pneumatic drill and a
two inch Merrit Wheel. The inside diameter of the crankshaft must be clean and free of
any sludge residue prior to installing a new oil control plug.
3. Two special tools (Oil Control Plug Installation Tool (Table 10-34) and Oil Control
Plug Leak Test Fixture (Figure 2-12)) are required to perform this procedure. The tools
are designed especially for this application. The 2.375-inch diameter collar at the rear
of the Oil Control Plug Installation Tool prevents driving the oil control plug beyond
the specified depth for the plug in the crankshaft (see Table 10-34).

Table 10-38. Crankshaft Oil Plug Installation Specifications

Engine Model Installation Tool Depth of Plug in Crankshaft
IO-360, LTSIO-360, TSIO-360 Figure 2-8 4.44 - 4.46 inches
O-470-G, IO-470-C, H, J, K, L & N Figure 2-9 5.91 - 5.93 inches
O-470-B, E, M, R, S & U
IO-470, D, F, M, S, U & V Figure 2-11 4.96 - 4.98 inches
TSIO-470
520 & 550 Sandcast Figure 2-11 4.92 - 4.94 inches
520 & 550 Permold Figure 2-10 4.66 - 4.68 inches
CAUTION: Do not use makeshift tools to perform this procedure.
Non-conforming tools can damage components, rendering them
unusable.
NOTE: Ensure the threaded hole in the oil control plug is facing toward the
propeller flange at installation.
4. Carefully drive in the new oil control plug into the crankshaft using an air impact
hammer and the Oil Control Plug Installation Tool.
5. Leak test the oil control plug and pressure test the crankshaft by connecting the Oil
Control Plug Leak Test Fixture (Figure 2-12) to the crankshaft using a C-clamp with
neoprene rubber pads as shown in Figure 10-39. Apply 70-80 psi air pressure and close
the air supply. Monitor the pressure gauge for 15 seconds; allowable pressure loss is
not to exceed 2 psi.

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6. After all crankshaft repairs have been completed, restore the helix pattern to the
exposed portion of the crankshaft according to instructions in Section 10-9.3.

Figure 10-39. Crankshaft Oil Control Plug Leak Test

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10-9.3. Crankshaft Plating Overhaul
1. Remove any tin plating on the crankshaft in the one inch area shown in Figure 10-40 by
rubbing a piece of very fine emery cloth, buffing around the shaft to attain a smooth
uniform finish without any scratches.
2. Apply a ½-inch wide strip of 180 grit emery cloth against the newly polished one inch
area on the crankshaft with firm hand pressure to lightly scratch (not score or gouge) a
new helix design in a 30° pattern in the plated area as shown in Figure 10-40. Rub the
emery cloth in the plated area outward toward the propeller flange, counter-clockwise.
For left-hand rotating engines, rub clockwise. The helix promotes proper seating of the
crankshaft oil seal and a better seal to help prevent leakage.
3. After preparing the first quarter portion, rotate the crankshaft by hand so that the next
portion is visible and continue rubbing with the 180 grit emery cloth until the entire one
inch plated area (Figure 10-40) around the crankshaft is lightly scratched with the
helical design.
4. Flush the particles from the crankshaft with mineral spirits.
5. Wipe the plated area with the lightly scratched helical pattern on the crankshaft with
acetone. Ensure the crankshaft is free of any debris or particulate matter to facilitate
clean sealing.
CAUTION: Adequately mask the propeller flange bolt holes and the
forward prop contact surface to prevent paint damage to nut/washer
bearing surfaces.
6. Mask the crankshaft except for the area prepared in the previous steps to prevent over
spray. Apply a single coat of high-performance rust preventive acrylic enamel
(designed for steel), minimal thickness required for coverage, not on load bearing
surfaces according to the paint manufacturer’s instructions to the portion of the
crankshaft which will be exposed to the elements. Allow the paint to dry to the touch.

Figure 10-40. Crankshaft Helix Pattern

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10-9.4. Connecting Rod Replacement
WARNING
Never remove material from a connecting rod. The removal of
metal from connecting rods, crankshafts or pistons, for the
purposes of balancing, is not an approved procedure.
Removing material from a connecting rod will destroy the shot
peen treatment and may cause stress risers. Connecting rods
are matched to limit engine vibration with no more the 1/2
ounce weight variance allowed between connecting rods in
opposing cylinder bays.
CAUTION: For dynamic balance, connecting rod assemblies are
paired with a maximum weight variation of one-half ounce (14
grams) between opposing bays. For this reason, connecting rods
must be replaced in pairs.
NOTE: The allowable weight variation between pistons and connecting
rods does not apply to the entire set. Connecting rod and piston weight
variations are limited to opposing bays.
1. Remove the connecting rods according to the instructions in the primary Instructions
for Continued Airworthiness(Section 1-1.1).
2. Clean the connecting rods with an approved solvent or degreaser. Verify all surfaces are
free of varnish, oil, or residue that will affect reliability of visual, dimensional and
magnetic particle inspections.
10-9.4.1. Connecting Rod Dimensional Inspection
1. Verify the connecting rod and cap mate marks are aligned and the position numbers
stamped on or adjacent to the bolt boss match. Scrap connecting rods and caps with
mate marks that do not align.
2. Visually inspect the connecting rods for corrosion, pitting, discoloration (bluing),
galling, bending, twisting, impact damage or nicks. Scrap connecting rods with any of
these indications.
3. Weigh the connecting rods within opposing cylinder pairs (1 vs. 2, 3 vs. 4, etc.) with a
calibrated scale, accurate to one-half ounce, and record the weight variation. Discard
connecting rod pairs exceeding 1/2 ounce maximum weight variation.
4. Visually inspect the connecting rod and cap parting surface. Contact signatures
resulting from assembly forces are normal and acceptable. Connecting rods exhibiting
fretting signatures, indicated by erosion of the original machining marks, either locally
or over the entire surface, are not acceptable for continued service. Scrap connecting
rods with fretting at the parting surfaces; do not attempt rework.
5. Visually inspect the nut seat area. Excessive fretting signatures indicate material loss.
Scrap connecting rods with edge loading under the bolt head surface contact area.
6. Visually inspect dowel surfaces at the rod and cap bolt holes. Scrap connecting rods
with fretting at the dowel surface.

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7. Align the mate marks on matching position numbers and assemble the connecting rod
and cap by installing a bolt through the cap and rod. With the cap seated firmly against
the rod, you must be able to install the remaining bolt using hand pressure only. Scrap
connecting rods if the bolts cannot be installed by hand.
8. Lubricate the connecting rod bolt and nut threads with clean 50 weight aviation oil.
9. Install and torque the nuts and bolts to Appendix B specifications.
10.Inspect the inside diameter joint of the rod to cap with both bolts and nuts installed and
torqued; mismatch (or a step) must be less than 0.001 inch. To check for a mismatch:
place the rod on a surface plate with the split line at the 6 and 12 o'clock position; use
V-blocks to hold the connecting rod in place. Use a dial indicator mounted on a height
gauge, zero out on one side of the split line and move the indicator across the split line;
a mismatch (or a step) of more than 0.001 inch is not acceptable.
WARNING
Removing and installing the piston pin bushing with makeshift
tools will damage connecting rods.
11. Remove the piston pin bushings from the connecting rod using a Connecting Rod
Bushing Removal/Installation Set (Borroughs Part No. 8098, or equivalent) and an
arbor press.
12.Inspect the piston pin bushing bore and surrounding area for nicks, gouges and
mechanical damage. Scrap connecting rods with any of these indications.
13.Use precision measuring equipment, such as a dial bore gauge or air gauge; verify the
connecting rod meets the dimensional specifications in Figure 10-41 and Table 10-39.
14.Measure the inside diameter of the rod and cap within 30° of the rod and cap joint; take
a second measurement 90° from the first. Both measurements must meet dimensional
specifications in Figure 10-41 and Table 10-39; the difference between these two
measurements is an indication of out-of-round and must not exceed 0.0015 inches.
Scrap connecting rods and caps which fail to meet dimensional specifications in Figure
10-41 and Table 10-39 or exceed 0.0015” out-of-round. Scrap connecting rods and caps
which fail to meet these specifications.
15.Inspect the connecting rod channel rails for nicks, gouges or mechanical damage. Scrap
connecting rods with any of these indications.
16.Perform a “Connecting Rod Magnetic Particle Inspection” according to the instructions
in Section 11-3.1.

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WARNING
Failure to comply with the specifications and instructions
depicted in Figure 10-41 will result in engine malfunction and/
or stoppage.

Figure 10-41. Connecting Rod Dimensions

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Table 10-39. Connecting Rod Specifications

Connecting Piston Pin

Rod Bores Piston Pin Bushing Connecting
1, 2
Connecting Forging Nut P/N Centerline Bore I.D. I.D. Crankpin Rod End
Rod Part Part Distance (No Bushing) Bushing P/N Bore I.D. Width
Engine Model Number Number Bolt P/N “A” “B” “C” “D” “E”

WARNING
If the Hardware listed in the footnotes at the end of the Table is
not available, replace the obsolete connecting rod assembly with
replacement (later) configuration listed for the engine model.

O/IO/TSIO-470 655910 3 646126 654490 Nut 6.6230 1.2340 1.1267 2.3755 1.521
 Superseded Superseded 6.6270 1.2350 1.1269 2.3760 1.525
Small Bore 655000 632041 655958 Bolt
IO & TSIO-520 655004 530658
 654999
IO-346 646778

E- Series 654796 3, 4 646126 654487 Nut 6.6230 1.2340 1.1263 2.3755 1.583
 Superseded Superseded 6.6270 1.2350 1.1265 2.3760 1.587
O-470- 646478 632041 655960 Bolt
2,4,11,13A,15 530658
 A361215
IO-470-
C,G,J,K,P,R

654793 3, 4 646116 654487 Nut 6.3730 1.0620 1.000 2.0615 1.2215

360 Large Bore
IO-240 Superseded Superseded 6.3770 1.0630 1.0005 2.0620 1.2255
646320 626119 655959 Bolt
IOF-240
642268 538684

654794 3, 4 646116 654487 Nut 6.3730 1.0620 1.000 2.0615 1.3015

360 Small Bore Superseded Superseded 6.3770 1.0630 1.0005 2.0620 1.3055
GO-300 646321 626119 655959 Bolt
626128 538684

654795 3, 4 646116 654487 Nut 6.3730 1.0620 0.9230 - 2.0615 1.3015

O-200  0.9235
Superseded Superseded 6.3770 1.0630 2.0620 1.3055
O-300 646322 626119 655959 Bolt
C-90  530192
530184 6 530186 6
C-145
5561 6

655911 3 646126 654490 Nut 6.6230 1.2340 1.1267 2.3755 1.461

IO / TSIO-520 Superseded Superseded 6.6270 1.2350 1.1269 2.3760 1.465
Large Bore 632041 655958 Bolt
655005 4
TSIO-520-BE 530658
646476
646475

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Table 10-39. Connecting Rod Specifications

Connecting Piston Pin

Rod Bores Piston Pin Bushing Connecting
Connecting Forging Nut P/N 1, 2 Centerline Bore I.D. I.D. Crankpin Rod End
Rod Part Part Distance (No Bushing) Bushing P/N Bore I.D. Width
Engine Model Number Number Bolt P/N “A” “B” “C” “D” “E”

655910 3 646126 654490 Nut 6.6230 1.2340 1.1267 2.3755 1.521

Superseded Superseded 6.6270 1.2350 1.1269 2.3760 1.525
L/TSIO-520-AE 655000 4 632041 655958 Bolt
530658
646480
643166

TSIO-520-CE 655911 3 646126 654490 Nut 6.6230 1.2340 1.1267 2.3755 1.461
IO-550 Superseded Superseded 6.6270 1.2350 1.1269 2.3760 1.465
TSIO-550 655001 632041 655958 Bolt
TSIOL-550 646482 530658

IO-550-B29, 655911 3, 7 646126 654490 Nut 6.6230 1.2340 1.1267 2.3755 1.461
B33, B37, C25, Superseded Superseded 6.6270 1.2350 1.1269 2.3760 1.465
C30 655001 632041 655958 Bolt
654440 530658
TSIO-520-
UB17

655910 3 646126 654490 Nut 6.6230 1.2340 1.1267 2.3755 1.521

Superseded Superseded 6.6270 1.2350 1.1269 2.3760 1.525
GTSIO-520
655004 632041 655958 Bolt
530658

1. The most current part number connecting rod nuts and bolts must not be used on or with superseded part number nuts and bolts
2. See Appendix B for Nut and Bolt torque specifications
3. Connecting Rod Assembly must use corresponding Bolt and Nut specified in column 4 of table.
4. Current part number (serviceable) connecting rods must use the most current part number connecting rod new nuts and bolts. The most
current connecting rod new nut and bolt part numbers can be used with old (serviceable) connecting rods of the same style. (Hex head rod
bolts must replace hex head rod bolts, contour head rod bolts must replace contour head rod bolts.)
5. Part No. A36121 connecting rod assemblies utilizing Part No. 632041 forging must be serviced according to table. 
Part No. A36121 connecting rod assemblies utilizing the Part No. 40742 forging must be serviced with Part No. 35972 connecting rod bolt,
Part No. 24804 nut and Part No. MS24665-132 cotter pin; torque to the value specified in Appendix B.
6. Part No. A36121 connecting rod (identified by forging number 530186), A35159 (Identified by forging number 5561) and A35160 (Also
identified by forging number 5561) must be serviced with Part No. 530213 bolt, Part No. 24804 or Part No. 626140 nut and Part No. 639292
cotter pin, torqued to value specified in Appendix B.
7. Used in Balanced Set Part No. 655913

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10-9.4.2. Connecting Rod Piston Pin Bushing Replacement
Replace all connecting rod piston pin bushings at overhaul.
Equipment Required
• Arbor press
• Borroughs Part No. 8098, Connecting Rod Bushing Removal/Installation Set, or
equivalent
• Borroughs Part No. 8111A, Connecting Rod Boring and Alignment Fixture, or
equivalent
• High speed borer of the correct size
• Borroughs Part No. 8042C Adapter Kit, or equivalent (E-Series, 470, 520 engines) or 
Part No. 8072C (240, 300, 360 engines), or equivalent
• Vertical mill, or equivalent, capable of maintaining 1750 RPM.
• Federal Dimension D-2500 or D-4000 Air Plug Gauge with a 1.1268 setting ring and
1.1268 air plug, or equivalent)
• Profilometer
WARNING
Use only the special tools listed. Removing and installing
connecting rod bushings with makeshift tools can damage the
connecting rods.
Verify the piston pin bushing being installed is the correct part number for the application.
Use a Connecting Rod Bushing Removal/Installation Set (Borroughs Part No. 8098 or
equivalent) and an arbor press to install the piston pin bushing as follows:
1. Press out the old piston pin bushing using the Connecting Rod Bushing Removal/
Installation Set and an arbor press. Verify the connecting rod bore is smooth.
2. Verify the new bushing part number. Dip the new piston pin bushing in clean 50 weight
aviation engine oil before placing it in position. The bushing may be chilled to aid
installation.
3. Visually inspect the piston pin bushing bore to determine acceptability of parts. No
nicks or gouges are permissible on the bore after the bushing is removed. Discard the
connecting rod if nicks/gouges are found.
4. Position the connecting rod over the pilot so the mate marks and piston pin bore
chamfer are facing up.
5. Place the piston pin bushing on the pilot so that the bushing split is located 45° ± 5°
from the center line of the connecting rod, facing the crankpin end. Refer to the
Connecting Rod dimensions in Figure 10-41 and Table 10-39.
6. Position the ram onto the pilot.
7. Using the arbor press, carefully press the new piston pin bushing flush with the piston
pin bore.

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8. Bore the new piston pin bushing to the diameter specified in Figure 10-41 and
Table 10-39 according to the “Connecting Rod Piston Pin Bushing Boring” in
Section 10-9.4.3.
9. Visually inspect the connecting rod for nicks or damage that may have occurred during
bushing installation. Scrap connecting rods exhibiting these conditions.
10.Verify the piston pin bushing split line meets Figure 10-41 specifications.
11. Because of the close tolerances required, inspect the new piston pin bushing; note the
bushing bore inner diameter must meet Table 10-39 specifications:
a. Use a Federal Dimension Air Gauge (with the appropriate setting ring and air
plug) to verify that the piston pin bushing is within the connecting rod minimum
and maximum limits specified in Table 10-39.
b. Check the piston pin bushing surface finish with a profilometer. The surface
finish must not exceed 16 Ra.
c. Check the connecting rod bushing for alignment and twist after bushing
installation using the Connecting Rod Boring and Alignment Fixture (Borroughs
Part No. 8111A or equivalent). To check the connecting rod twist, insert the push-
to-fit arbors into the pin and crank end of the rod.
d. Place the connecting rod crank pin end onto the V-blocks.
e. Place the pin end arbor on the two machined parallel steel blocks spaced equal
distance from the center line of the rod, but not less than 6 inches apart.
f. Use a flat feeler gauge to detect clearance between the machined steel blocks and
the pin end arbor. Refer to the connecting rod dimensions in Table 10-39 for
specified limits.
g. To check the connecting rod alignment, rotate the pin end of the connecting rod
to a vertical position and with the arbor resting against a positive stop.
NOTE: The piston pin bushing must be bored to the proper inside
diameter according to the “Connecting Rod Piston Pin Bushing Boring”
instructions in Section 10-9.4.3.
h. Using a dial indicator mounted on a vertical stand resting on the surface plate,
measure the vertical distance of the pin end arbor from the surface plate at points
of equal distance from the centerline of the connecting rod. Compare the
connecting rod measurements to the connecting rod dimensions in Table 10-39.
Connecting rods exceeding Table 10-39 limits must have the piston pin bushing
replaced and reamed or the connecting rod must be scrapped.

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10-9.4.3. Connecting Rod Piston Pin Bushing Boring
Equipment Required
• Borroughs Part No. 8111A, Connecting Rod Boring and Alignment Fixture, or
equivalent
• Adapter Kit
• Vertical mill, or equivalent, capable of maintaining 1750 RPM
• Boring tool of the correct sizes

1. Place the connecting rod on the base plate and secure with retainers provided.
2. Select the correct adapter kit and boring tool for the connecting rod.
3. Using a vertical mill, or equivalent, bore the connecting rod bushing to size. Maintain
1750 RPM during the boring process.

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10-10. Crankshaft Nose Oil Seal Replacement
Replace the crankshaft nose oil seal if it is damaged or if the following conditions exist:
• Ram air is entering the engine interior
• Oil leaks from the nose seal or nose seal retainers
10-10.1. Solid Nose Oil Seal Removal
NOTE: Instructions in this section apply only to stretch over type oil
seals.
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
1. Turn the Ignition Switch OFF and disconnect engine electrical power.
2. Disconnect all spark plug leads.
3. Set the brakes and block the aircraft wheels.
4. Ensure that aircraft tie-downs are installed and the cabin door latch is open.
5. Remove the propeller according to the propeller and aircraft manufacturer’s
instructions.
CAUTION: Do not scratch, mar, or damage the crankshaft or
crankcase while removing the crankshaft nose oil seal.
6. Remove the screws and the retainer plates (Figure 10-42) from the crankcase.

Figure 10-42. Retainer Plate and Screws on Front of Crankcase

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7. Remove the crankshaft nose oil seal, reinforcing ring (if used), and spring as shown in
Figure 10-43). Gentle force may be required to remove the nose oil seal parts from the
counterbore.
8. Inspect the propeller mounting flange carefully to insure that no nicks, burrs or sharp
edges are present which could damage the oil seal surface during installation.
9. Clean surfaces thoroughly making certain that no foreign material remains on the shaft
or in the seal counterbore. Wash oil seal counterbore area with acetone. To remove the
Gasket Maker residue out of the counterbore recess using a chlorinated solvent such as
Loctite Chisel or methylene chloride followed by a naptha solvent such as Loctite
ODC-Free Cleaner and Degreaser. Remove all residue and debris from the bore.

Figure 10-43. Crankshaft Nose Oil Seal Parts

10.Prepare the exposed portion of the crankshaft according to the instructions in
Section 10-9.3.
10-10.2. Solid Nose Oil Seal Installation
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
1. Prepare the exposed portion of the crankshaft with a fresh helix pattern according to
instructions in Section 10-9.3.
2. Remove the spring and reinforcing ring from the crankshaft nose oil seal.
3. Unhook the spring ends using an unwinding motion.
4. Verify the seal spring length is 7.80” to 7.83” as illustrated in Figure 10-43. If the
spring length is not within this tolerance, replace it.
5. Place the spring around the crankshaft in the helix area.

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6. Turn the spring ends in a winding direction and allow one end to wind into the other
end.
7. Apply Part No. 654561 Grease to the lip of the new seal and the propeller flange.
8. Squeeze the seal until it is egg shaped and install it on the crankshaft, groove side in,
starting from the bottom of the propeller flange using the Crankshaft Oil Seal Installer
Tool (Chapter 3, Kent-Moore Part No. 5209).
9. After the oil seal is installed on the crankshaft, wipe the grease from the oil seal and
crankshaft. Verify the outer diameter of the oil seal is clean and dry.
10.Press the reinforcing ring into the oil seal recess in both directions from the split.
Ensure the reinforcing ring is in the deepest part of the recess all the way around.
11. Install the spring in the oil seal cavity.
12.Spray a thin film of Part No. 653692 Primer on the oil seal counterbore and allow it to
dry for 1 to 2 minutes.
13.Apply a translucent coat of Gasket Maker (Part No. 646942) to the oil seal counterbore.
Refer to Gasket Maker application instructions in Appendix C.
14.Apply Gasket Sealant (Part No. 654663) to the outside diameter of the oil seal.
15.Using thumb pressure, work the seal into the crankcase counterbore.
16.After the seal is in place, wipe any remaining sealant from the seal and crankshaft.
17.Spray the exposed portion of the lightly scratched crisscross area with aluminum paint
and allow it to dry.
18.Apply Part No. 653693, General Purpose Primer, to the crankcase oil seal retainer
screw holes.
19.Apply Part No. 646941, High Strength Adhesive Sealant, to the oil seal retainer screws.
20.Install the crankshaft nose oil seal retainer plates and secure them with the nose oil seal
retainer screws. Torque the screws to Appendix B specifications.
21.Inspect the propeller according to the propeller manufacturer’s and aircraft
manufacturer’s instructions.
22.Install the propeller, if serviceable, according to the propeller manufacturer’s and
aircraft manufacturer’s instructions.
23.Perform a normal “Engine Start” (Section 7-3.2) and “Ground Run-up” (Section 7-3.3).
Run the engine for a minimum of five minutes to reach normal operating temperatures.
Shut down the engine according to the “Engine Shutdown” (Section 7-3.4) instructions
and inspect the Crankcase Nose Oil Seal area for leaks.

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10-10.3. Split Nose Oil Seal Removal
Follow same procedures listed for stretch type oil seals except it is not necessary to
remove the propeller. With the propeller installed, any removal of plating or blending of
the 1” area referred to in Section 10-10.1 will have to be accomplished manually without
engine rotation.
NOTE: On left hand rotating engines (LTSIO360) the helix must be
applied in the opposite direction as shown in Figure 10-40. Stroke the
strip of emery cloth outward toward the flange in the direction of rotation
(CW toward you using maximum hand pressure.).
10-10.4. Split Type Nose Oil Seal Installation
1. Prepare the exposed portion of the crankshaft with a fresh helix pattern according to the
instructions in Section 10-9.3.
2. Use appropriate split type nose oil seal depending on engine model (refer to illustrated
parts catalog).
3. Remove the spring (Figure 10-44) from the new crankshaft nose oil seal assembly and
unhook the spring ends.
4. Verify the seal spring length is 7.53” to 7.59” as illustrated in Figure 10-44. If the
spring length is not within this tolerance, replace it.
5. Place the spring around the crankshaft in the helix area and connect the ends of the
spring.
6. Apply Part No. 654561 Grease to the lip of the new oil seal and the crankshaft propeller
flange.
7. Install a new oil seal on the crankshaft outboard of the spring with the opening facing
the crankcase.
CAUTION: The nose oil seal split line must not align with the
crankcase mating flanges.
8. Position the split line of the crankshaft nose oil seal at the 2:00 or 4:00 o’clock position
of the crankcase.
9. Position the spring hooks 180° away from the split line of the nose oil seal and install
the spring in the oil seal cavity.
10.After the seal is positioned on the crankshaft, wipe the grease from the oil seal and
crankshaft. Verify the outer diameter of the oil seal is clean and dry.
11. Mask the crankshaft where it exits the crankcase. Spray a thin film of Part No. 653692,
Primer, on the oil seal counterbore and allow it to dry for one to two minutes.
12.Apply Part No. 646942, Gasket Maker to the crankcase oil seal counterbore. Remove
the masking tape from the crankshaft.
13.Apply a translucent coat of Part No. 654663 Gasket Sealant on the outer diameter of
the oil seal.

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14.Using thumb pressure, work the seal and spring into the crankcase counterbore. Ensure
the seal is in the deepest part of the recess all the way around.

Figure 10-44. Split Nose Oil Seal Parts

15.After the seal is in place, wipe any remaining sealant from the seal and crankshaft.
16.Spray the exposed portion of the lightly scratched crisscross area with aluminum paint
and allow it to dry.
NOTE: The following steps apply only to engines utilizing oil seal
retainer plates.
17.Apply Part No. 653693, General Purpose Primer, to the crankcase oil seal retainer
screw holes.
18.Apply Part No. 646941, High Strength Adhesive Sealant, to the oil seal retainer screws.
19.Install the crankshaft nose oil seal retainer plates and secure them with screws. Torque
the screws to the value specified in Appendix B.
20.Perform a normal “Engine Start” (Section 7-3.2) and “Ground Run-up” (Section 7-3.3).
Run the engine for a minimum of five minutes to reach normal operating temperatures.
Shut down the engine according to the “Engine Shutdown” (Section 7-3.4) instructions
and inspect the Crankcase Nose Oil Seal area for leaks.

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10-11. Exhaust Flange to Cylinder Installation
Exhaust systems on most turbocharged engines are supplied with the engine. Exhaust
systems on naturally aspirated engines are supplied by the aircraft manufacturer.
Continental recommends the following information for connecting the exhaust flange to
the cylinder, regardless of the source of the exhaust system:
1. Before connecting the exhaust system to the cylinder(s), inspect the cylinders, exhaust
flanges, and exhaust studs for serviceability and security (see Section 6-4.21 and the
primary ICA).
2. Install gaskets and properly position the exhaust system on the cylinders. Ensure the
exhaust flanges mate properly to the cylinder.
3. Lubricate the exhaust studs with clean 50 weight aviation engine oil.
4. Evenly torque exhaust nuts to the specified torque value in Table 10-40 and
Appendix B.
5. Perform ground run-up to normal operating temperature according to the Airplane
Flight Manual/ Pilot’s Operating Handbook (AFM/POH) published by the aircraft
manufacturer.
6. Inspect exhaust system for leaks and security prior to return to service (Section 6-4.21).
7. After completing ground run-up, re-torque exhaust nuts to final torque value.

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Table 10-40. Exhaust Gaskets, Nuts, and Nut Torque Values
TORQUE VALUE
ENGINE MODELS GASKET NUT IN. LBS. FT. LBS. NOTES
A65
C75
All Models 22022 200-210 16.7-17.5
C85
C90
O200 A, B, C, D & X MS20500-524 100-110 8.3-9.2
C125 632837
or 22022 200-210 16.7-17.5
C145 652459
O300
MS20500-524
GO300 All Models
E165 100-110 8.3-9.2
E185 MS20500-428
E225
IO240
IOF240
Use two each gaskets per exhaust port,
IO360 All Models 630365 22022 200-210 16.7-17.5
concave sides together.
LTSIO360
TSIO360

All Models 631544

(except J) or 4-Hole Gasket
652458
O470
632837
J Model Only or MS20500-428 100-110 8.3-9.2 2-Hole Gasket
652459
All Models 631544
(except J & K) or 4-Hole Gasket
652458
IO470
J & K Models 632837
Only or 200-210 16.7-17.5 2-Hole Gasket
652459
TSIO470
631544
IO520 All Models or MS20500-428 100-110 8.3-9.2 4-Hole Gasket
652458
GTSIO520
LTSIO520 AE Model Only 652459 2-Hole Gasket

All Models 631544

except AE or MS20500-428 100-110 8.3-9.2 4-Hole Gasket
TSIO520 652458
AE Model Only 652459 2-Hole Gasket
IO550
IOF5550
631544
TSIO550 All Models or MS20500-428 100-110 8.3-9.2 4-Hole Gasket
652458
TSIOF550
TSIOL550

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Intentionally Left Blank

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Chapter 11. Non-Destructive Inspection
11-1. Visual Inspection
Perform a visual inspection on all parts not specified as 100% replacement (Appendix C-
2.3 or C-2.4) at overhaul. Examine parts prior to being cleaned for obvious evidence of
wear or leakage. Reject obviously damaged parts during the preliminary visual inspection,
there is no need to clean and perform non-destructive inspection on parts which cannot be
used. If condition is uncertain, clean with remaining parts after the preliminary exam,
according to the “Engine Cleaning” instructions in the Chapter 12. Verify the parts are
clean and free of all carbon, dirt, grease, oil, soot, varnish, gum, and paint.
1. Visually inspect the parts using at least a 10X (power) magnifying glass under good
lighting. Look for the following unacceptable conditions:

• Nicks • Pitting
• Dents • Metal transfer
• Gouges • Corrosion
• Cracks • Erosion
• Distortion • Enamel coating wear
• Burned areas
2. Inspect all studs for bending, looseness or partial removal.
3. Inspect all threaded parts for nicks, damaged or deformed threads, faces, or heads.
4. Identify areas that warrant further cleaning.
5. Label parts which fail inspection; indicating reason for failure and if repair is
possible or if replacement is required.

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11-1.1. Gear Tooth Inspection
Inspect the gear teeth for signs of overheating and wear. Normal wear produces a fine
polish on the tooth thrust faces. Gears with uneven teeth profiles, score marks, burning, or
pitting are unacceptable. Refer to Figure 11-1 for sample illustrated comparisons of
acceptable and unacceptable gear wear.
Discard and replace unacceptable gears.

Figure 11-1. Gear Inspection Criteria

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11-2. Fluorescent Penetrant Inspection
Perform this inspection on all cleaned, aluminum or non-ferrous metal parts, including the
parts listed below in accordance with ASTM E1417, E1208, E1209, E1219, and Type 1
Fluorescent Penetrant Method A, B, C, or D. For accurate results, parts should free of
paint and all foreign substances, such as carbon, dirt, grease, oil, soot, varnish, gum, and
paint. Inspection shall be performed by personnel certified to Level II using methods
approved by a Level III certified inspector.

Table 11-1. Parts Requiring Fluorescent Penetrant Inspection

Inspect: Pay particular attention to:
• Accessory case, including oil • Areas where oil seals or bushings are pressed in or seated
pump cavity • Bearing bosses
• Accessory drive housing • Area between cylinder head cooling fins
• Brackets (non-ferrous) • Areas surrounding through-bolt holes
• Crankcase halves • Crankcase/crankshaft exit area
• Cylinder heads • Cylinder-to-barrel mating area
• Engine mounts • Intake and exhaust flanges
• Induction manifolds • Intake and exhaust ports
• Induction risers • Oil pump cavity area mounting flanges
• Induction tubes • Mounting and attaching areas where hardware has been previously
• Intake/exhaust valves torqued
• Oil cooler mount • Rocker boss areas
• Oil filter adapter • Shaft bores
• Oil sumps (non-ferrous) • Valve seat insert areas
• Starter adapter housings • Valve guide areas

Unless the overhaul repair instructions in the Maintenance and Overhaul (or Overhaul)
Manual contains specific instructions to remedy unsatisfactory conditions discovered
during the inspection, discard parts which exhibit any of the conditions described in steps
1a through 1c.
1. Inspect non-ferrous parts for the following conditions:
a. Cracks, or indications of the start of cracks
b. Unauthorized grinding encountered after the manufacturing process.
c. Unauthorized welding
2. Look for indications which break into corners, edges, holes, or fillets on parts.
Identify parts that contain linear indications; repair is authorized by licensed repair
station only.
3. Follow the fluorescent penetrant manufacturer's instructions for the equipment and
materials used to perform the inspection regarding use, safety data, and disposal.
4. Label each part’s inspection status and required action.
5. Follow the fluorescent penetrant manufacturer’s instructions to remove penetrant
residue from the inspected, serviceable parts.

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11-3. Magnetic Particle Inspection
Prior to performing a Magnetic Particle Inspection, verify the parts are clean and free of
carbon, dirt, grease, oil, soot, varnish, gum, and paint. Plating shall not be intentionally
removed.
CAUTION: Prior to Magnetic Particle Inspection, ensure that the parts
have been thoroughly cleaned and dried according to the instructions in
of the Maintenance and Overhaul (or Overhaul) Manual.
The Magnetic Particle Inspection must be performed by a certified technician on cleaned,
ferrous parts according to ASTM E1444 using the wet continuous method and full wave
rectified alternating current and fluorescent particles. Follow the particular magnetic
particle media manufacturer's instructions regarding use, safety data, and disposal.
Inspection shall be performed by personnel certified to Level II using methods approved
by a Level III certified inspector.
1. Follow the equipment and materials manufacturer's instructions to perform the
inspection regarding use, safety data, and disposal. Use the corresponding method of
magnetization and amperage listed in Table 11-2. Perform circular, followed by
longitudinal inspection.
2. Inspect parts for the following conditions:
a. Cracks or indications of the start of cracks
b. Unauthorized grinding encountered after the manufacturing process
c. Pits
Unless the Maintenance and Overhaul (or Overhaul) Manual contains specific instructions
to remedy unsatisfactory conditions discovered during the inspection, discard parts which
exhibit any of the conditions described in steps 2a through 2c.
3. Record repair or replacement requirements.
4. Look for linear indications which may break into corners, edges, holes, thread roots,
fillets, gear tooth roots or keyways on parts. Identify parts which contain relevant
linear indications which cannot be reworked.
5. Label parts which fail inspection as such; indicate reason for failure and if repair or
replacement action is required. Repair is authorized by licensed repair station only.
6. Demagnetize the parts to less than 3 gauss.
7. Clean the inspected parts thoroughly according to the “Engine Cleaning”
instructions in Chapter 12.
CAUTION: When utilizing compressed air, wear OSHA approved
protective eye wear. Never exceed 30 psi when using compressed
gases for cleaning purposes (OSHA 1910.242(b)).Dry the parts with
compressed air.
8. Dry the parts with compressed air.

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Table 11-2. Magnetic Particle Inspection Reference

Method of
Part Magnetization Amperes Focus Inspect for
Circular  • Lobes • Heat stress cracks
Camshaft and  1500 • Journals • Cracks
Longitudinal • Drilled hole edges
Circular 
Connecting rod1 and  1500 All areas Cracks
Longitudinal
• Journals • Cracks
Circular • Fillets • Heat cracks
Crankshaft 2000 • Oil holes
• Thrust flanges • Flange cracks from prop
Longitudinal
• Prop flange strike
• Fin tips • Cracks
Circular 
• Fin roots • Heat stress cracks
Cylinder barrels and  1500
• Flange
Longitudinal
• Flange bolt holes
Circular  • Teeth
Gears and  1000 to 1500 • Splines Cracks
Longitudinal • Keyways
Circular  • Shear planes
2 and  1000 • Ends Cracks
Piston Pin
Longitudinal • Center
Circular 12 parts on • Pad
1000
central conductor • Socket under side
Rocker arms arms and boss Cracks
Longitudinal 12 parts
1200
on central conductor
Circular  • Splines • Cracks
Shafts and  1000 to 1500 • Keyways • Heat stress cracks
Longitudinal • Section transitions
Through-bolts and Circular 
connecting rod and  500 Threads Cracks
bolts2 Longitudinal
1. Inspect connecting rod and cap according to the “Connecting Rod Magnetic Particle Inspection” in Section 11-3.1.
2. Perform only on in service parts; replace 100% at overhaul

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11-3.1. Connecting Rod Magnetic Particle Inspection
Before performing the “Connecting Rod Magnetic Particle Inspection,” the connecting
rod and cap must be clean and free of rust, scale, oil, or other residue that may affect the
reliability of the inspection.
1. Inspect the connecting rods using both the circular and longitudinal method of
magnetization.
NOTE: Use the “Fluorescent Penetrant Inspection” (Section 11-2)
method, wet continuous procedure, reference ASTM standards for non-
destructive testing.
2. Record inspection findings on a checklist. Refer to the Table 11-3 for inspection
pass/fail criteria.
NOTE: Reject connecting rod or caps exhibiting the unacceptable
indications listed in the Fail column of Table 11-3.
Table 11-3. Connecting Rod Magnetic Particle Inspection Criteria
Pass Fail
Steel inclusions or shallow imperfections on the forging
surface - light indications running parallel to the rod axis
Indications associated with cracks
or around the pin boss and cap ends less than ½-inch in
length
Blend area between the piston pin boss extending 1-inch Area of blend between the piston pin boss extending 1-
into connecting rod I beam, the bolt spot face areas and inch into connecting rod I beam, the bolt spot face areas
the channel rail edges are free of any indications of and the channel rail edges shows indications of cracks/
cracks/wear wear

Any indication transverse to the rod axis.

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 Non-Destructive Inspection
11-4. Ultrasonic Inspection
Reference: MSB96-10
The inspections must be performed on all six cylinder, spark ignited, aviation gasoline
(AvGas) engine crankshafts by technicians possessing inspection certification credentials
according to Section 11-4.1, “Ultrasonic Inspection Certification.”
The item to be inspected must have sufficient mass to perform the Ultrasonic Inspection.
Ultrasonic Inspection is not possible on four cylinder engine model crankshafts.
11-4.1. Ultrasonic Inspection Certification
Cylinder and crankshaft nondestructive testing (NDT) inspectors must possess a current
certification to perform the inspection according to Continental specifications. Training is
available from Plumstead Quality and Training Services (PQT) Company. PQT offers
training at various locations in the United States of America.
Courses available:
Continental Ultrasonic Testing Level I,
OR
Crankshaft Ultrasonic Testing Refresher, if previously certified as NDT Level II Inspector
(IAW NAS 410):
Consult the PQT web site for additional information:
Plumstead Quality and Training Services Company (PQT)
Phone: (904) 425-1381
www.PQT.net

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Non-Destructive Inspection
11-4.2. Crankshaft Ultrasonic Inspection
Reference: MSB96-10
Perform an Ultrasonic Inspection on each crankshaft removed from the engine at the next
and each subsequent removal from the engine according to the latest version of
Continental Material Handling Specification (MHS) 200.
NOTE: The ultrasonic inspection requirements set forth in the latest
revision of MSB96-10 instructions must be performed on crankshafts
prior to installation. Ultrasonic inspection is performed on Continental
Factory new crankshafts prior to shipment to the customer and need not
be repeated prior to initial installation.
NOTE: Any crankshaft listed in the latest revision of Continental Service
Bulletin CSB96-8 that is NOT verified as being a vacuum arc remelted
(VAR) forging, must be replaced upon discovery.
WARNING
Do not steel stamp the inspection result on the crankshaft, it
will dam age the nitride finish. Genuine Continental
Crankshafts are stamped prior to nitride treatment.

Table 11-4. Crankshaft Ultrasonic Inspection Pass/Fail Action

Crankshaft Meets Inspection Criteria Crankshaft Fails Inspection Criteria
Vibro-etch the crankshaft flange as illustrated in - Remove the crankshaft from service.
Figure 11-2 with both a “V” (vacuum arc remelted - Destroy the crankshaft to so that it is no
(VAR) verified) and a “U” (ultrasonic inspection) to longer “serviceable or airworthy.”
identify the inspection method: - Replace the crankshaft with a new or
VAR Steel/Ultrasonic Inspected  serviceable VAR crankshaft.
V/U (Figure 11-2) - Record inspection results
NOTE: In some instances, the VAR identification may have been ground
off in the balancing process and cannot be verified. If the VAR indication
cannot be verified, replace with a new or serviceable VAR crankshaft.

Figure 11-2. Crankshaft Ultrasonic Inspection Method Location

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 Engine Cleaning
Chapter 12. Engine Cleaning
12-1. Engine and Component Cleaning
The goal of cleaning engine components is to remove dirt and contamination. A “cleaned”
part is free of dirt, carbon, varnish, and gum substances. The “Aircraft Engine Parts
Cleaning Guidelines”, (see Table 12-1) offer instructions for specific engine parts during
overhaul or maintenance. Refer to the “Cleaning Tips” in Table 12-2 for additional
guidelines.
WARNING
Consult the manufacturer’s Safety Data Sheet (SDS), formerly
Material Safety Data Sheet (MSDS), for specific handling,
storage and disposal instructions, including personal protective
equipment requirements.
To prevent death or injury, do not smoke or introduce sources
of ignition or flame to the work area when using flammable
cleaning fluids such as mineral spirits.
Do not use gasoline, kerosene, abrasive cleaning paste, or
cleansing powder to clean the engine or engine parts.
Do not pressure blast gears with abrasive media. Blasting will
remove surface hardening.
When cleaning with alkaline solutions, remove all traces of
alkaline residue to prevent corrosion. Alkaline cleaning
solutions induce corrosion if not completely removed.
NOTE: Prior to cleaning engine parts, visually inspect for leakage and
metal shavings, rust or other obvious signs of wear.

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Engine Cleaning
Table 12-1. Aircraft Engine Parts Cleaning Guidelines
Item to Clean Instructions/References/Tips
Aluminum Parts, including:
• Accessory case
Flush with mineral spirits (preferred cleansing agent).
• Oil sump
Alkaline stripping bath followed by steam rinse to remove all alkaline traces (to
• Oil pump housing
prevent corrosion); Dry with compressed air and inspect for traces of alkaline
• Oil filter adapter
residue. Re-spray with steam if alkaline residue found; flush thoroughly with
• Tach drive adapter
mineral spirits.
• Starter adapter housing, cover
and oil passages
Aluminum alloy parts soiled or
stained with carbon or gum Refer to “Cleaning Aluminum Alloy Parts”in Section 12-1.4.
deposits
Flush with mineral spirits (preferred cleansing agent).
Alkaline stripping bath followed by steam rinse to remove all alkaline traces (to
Crankcase casting prevent corrosion); Dry with compressed air and inspect for traces of alkaline
residue. Re-spray with steam if alkaline residue found; flush thoroughly with
mineral spirits.
Crankcase oil passages Pressure flush with mineral spirits to remove clogs or free obstructed passages.
Oil squirt nozzles (Use caution flushing the oil squirt nozzles, they are not field replaceable)
CAUTION: When utilizing compressed air, wear OSHA approved
protective eye wear. Never exceed 30 psi when using compressed
gases for cleaning purposes. (OSHA 1910.242(b))
Thoroughly clean connecting rods using mineral spirits. Ensure that all surfaces
are free of varnish, oil and residue.
Place a sheet of crocus cloth on a flat surface plate and dampen with mineral
Connecting rods, caps, bolts, and spirits.
nuts Lightly rub the parting surface of the rod, cap and rod across crocus cloth to
remove burrs or nicks. Clean the connecting rods, caps, bolts and nuts
thoroughly.
Dry the cleaned part with compressed air and place on a clean cloth.
Connecting rod bearing inserts Clean the new bearing inserts in mineral spirits and dry with compressed air.
Degrease with mineral spirits (brushing or spraying).
Remove all varnish or gummy deposits. Place the crankshaft or camshaft in a
machinist’s lathe and rotate at approximately 100 RPM, smooth the following
with crocus cloth moistened in mineral spirits:
• Crankshaft crank pins
Crankshaft or camshaft
• Main journals
• Oil seal race
• Camshaft journals
• Gear mount flange
Clean all debris from bolt holes, threads, oil passages, and recesses
Crankshaft and camshaft gears1
Mineral spirits and a brass wire brush
with bushings2
Flush with mineral spirits (preferred cleansing agent).
Crankshaft and camshaft gears1 Alkaline stripping bath followed by steam rinse to remove all alkaline traces (to
without bushings prevent corrosion); after drying, inspect for traces of alkaline residue and re-
spray with steam. Flush alkaline residue with mineral spirits.

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 Engine Cleaning
Table 12-1. Aircraft Engine Parts Cleaning Guidelines
Item to Clean Instructions/References/Tips
Crankshaft counterweights1 Mineral spirits
Cylinders3 Refer to “Cylinder Cleaning” instructions in Section 12-1.1.
• Degrease intake valves with mineral spirits.
• Remove all carbon, varnish and gum either using a carbon solvent or by dry
Cylinder intake valves
blasting according to instructions in Section 12-2, “Dry Blasting.” If dry
blasting is performed, clean the valve with mineral spirits and air dry.
Cylinder baffles and cylinder
Mineral spirits
hardware
• Electrical contact cleaner CR4
• Do not use water-base or petroleum-base solvent to clean connectors
• If a cleaning fluid is suspected to have entered a connector, blow the excess
Electrical connectors away from the connector and place the effected component(s) in a warm
dry environment; i.e. 90F (32C), overnight or until thoroughly dry.
• As applicable, replace the sealant strip in the connector if any damage to the
seal is evident.
WARNING
Except when removing carbon deposits and gum (oil varnish),
do not use alkaline (caustic) cleaning solutions for external
engine cleaning. Alkaline solutions remove the alodine finish
of aluminum parts.
Engine and component exterior Spray or brush cleaning solvent (mild detergent or mineral spirits) on the engine
surfaces or engine component exterior.
Engine mount brackets Mineral spirits
Exhaust system multi-segment  Clean clamps using crocus cloth on the outer band of the clamp assembly. Use
V-band clamps Stoddard solvent to clean the rest of the clamp
CAUTION: Never insert any object (wire, pipe cleaner, brush, etc.)
in the fuel injector nozzle. If stain or obstruction cannot be removed
with solvent or air, replace the nozzle.
Fuel injectors
Cannot be cleaned; remove and replace fuel injectors
FADEC engines only
Immerse in an ultrasonic cleaner bath, adhere to the ultrasonic cleaner
Fuel injectors manufacturer's instructions.
Continental Continuous Flow If ultrasonic cleaner is not available:
Fuel Injection only • Acetone
• MEK
• Lacquer thinner
Fuel distribution block Soak in solvent (acetone, lacquer thinner or MEK) to remove gum and fuel
FADEC engines only varnish stains and deposits. Use clean, oil free air to remove residue and dry the
inside of nozzle.
Immerse in an ultrasonic cleaner bath, adhere to the ultrasonic cleaner
manufacturer's instructions.
Fuel filters/screens
If ultrasonic cleaner is not available, flush with clean Stoddard solvent into white
filter paper until no particulate residue is evident on the filter paper.

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Engine Cleaning
Table 12-1. Aircraft Engine Parts Cleaning Guidelines
Item to Clean Instructions/References/Tips
Fuel manifold valve Mineral spirits
Flush with mineral spirits (preferred cleansing agent).
Alkaline stripping bath followed by steam rinse to remove all alkaline traces (to
Gears without bushings1 prevent corrosion); Dry with compressed air and inspect for traces of alkaline
residue. Re-spray with steam if alkaline residue found; flush thoroughly with
mineral spirits
Gears1 with bushings2 Mineral spirits and a brass wire brush
Remove all old adhesive gasket material using the organic solvents listed below:
• Acetone
• Naptha
• Methyl ethyl ketone (MEK)
Gasket surfaces on castings When removing the crankshaft nose oil seal, clean the Gasket Maker residue
out of the counterbore recess using a chlorinated solvent Loctite Chisel or
methylene chloride followed by a naptha solvent such as Loctite ODC-Free
cleaner and degreaser. Remove all debris to render the bore clean, without any
trace debris.
NOTE: All oil passages must be clear.
Oil cooler/intercooler/aftercooler Must be cleaned by an FAA-certified repair facility
Oil suction tube assembly
Mineral spirits
Speed sensor (FADEC)
Overboost valve Stoddard solvent and compressed air to remove deposits
To remove heavy carbon deposits on the piston tops, use vapor grit method 
Piston tops
- Refer to “Vapor Blasting” in Section 12-3.
Soak in mineral spirits. Ensure passages within the pushrod and rocker arm are
open by flushing the passages with mineral spirits using a squirt bottle. Discard
Pushrods and rocker arms
and replace any pushrod or rocker arm that has obstructed passages and
cannot be cleared. Do NOT clean pushrods or rocker arms by dry blasting.
Spray or brush on mineral spirits to degrease the part.
Small steel parts
Soak heavily soiled parts for 15 minutes in mineral spirits.

Starter/starter adapter gears1 with

Mineral spirits and a brass wire brush
bushings2

Starter adapter worm shaft Mineral spirits

Spark plugs Clean according to manufacturer’s instructions.
Throttle control linkage pivot point
Stoddard solvent
areas
Stoddard solvent and compressed air to remove deposits. Apply Mouse Milk to
Turbocharger wastegate actuator
the bearing surfaces, shafts and pivot points. Tap the butterfly shaft (only the
and butterfly valve
shaft) with a rawhide mallet to free deposits.
1. Do not pressure blast gears or counterweights to clean them; blasting can remove the surface hardening
2. Do not use alkaline cleaning solutions
3. Do not use sand, glass shot, or metal grit to clean engine cylinders.

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 Engine Cleaning

Table 12-2. Cleaning Tips

Do Don’t
Except when removing carbon deposits and gum (oil
varnish), do not use alkaline (caustic) cleaning solutions
Use a cloth or compressed air to blow off the solvent.
for external engine cleaning. Alkaline solutions remove
the alodine finish.
Do not use any of the following to clean the engine or
parts:
Remove dirt (especially caked dirt) and debris from bolts, • Gasoline
nuts, and engine parts. • Kerosene
• Abrasive cleaning paste
• Cleaning powder
Do not scrape parts or use wire brushes, sandpaper,
Dispose of cleaning solvents in accordance with abrasive cloth or abrasive wheels unless specified in
Environmental Protection Agency (EPA), or equivalent Table 12-1 to clean or polish parts to prevent
regulatory agency regulations. concentrated stress to scratched areas and fatigue
failure.
Dry blast only with plastic media or natural materials such
as crushed walnut shells.
Do not use sand, metal grit, or glass beads for any type of
After a part is cleaned, machined, or repaired, or if the cleaning or dry blasting.
alodine finish is worn, apply alodine to aluminum surfaces
according to the instructions in Section 12-4.1

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Engine Cleaning
12-1.1. Cylinder Cleaning
CAUTION: When utilizing compressed air, wear OSHA approved
safety glasses, goggles or face shield. Never exceed 30 psi when
using compressed gases for cleaning purposes. (OSHA 1910.242(b))
1. Soak the engine cylinders in mineral spirits for 15 minutes. Dry the cylinder with
compressed air. Verify the cylinder is free of dirt and deposits. If the cylinder is
satisfactorily cleaned after a mineral spirit bath, proceed to step 4.
2. If caked on carbon deposits remain, remove oil and loose materials from engine
cylinders by spraying or brushing on a mild alkaline cleaner.
a. Spray the cylinder with steam to remove all traces of alkaline residue.
b. After the cylinder dries, inspect it again for traces of alkaline residue; respray
with steam if alkaline residue is still present (to prevent corrosion) and repeat
step 1.
3. For persistent carbon, varnish and gum deposits, dry blasting may be required.
a. Seal and protect all machined surfaces on the cylinder such as the cylinder mount
flange nut seats, barrel wall, small holes, and finished surfaces.
WARNING
Do not use sand, glass, shot or metal grit when dry blasting.
These abrasives can damage engine components. This type of
shot will become embedded in aluminum parts rendering them
useless.
b. Dry blast the cylinder to remove persistent carbon, varnish and gum deposits
according to instructions in “Section 12-2, “Dry Blasting.”
c. Clean the cylinder with hot, soapy water and a stiff bristled (non-wire) scrub
brush to remove blasting materials from the cylinder.
d. Thoroughly rinse the cylinder with hot water.
e. Wipe the cylinder bore with clean, soft white cloth and inspect cloth for cleaning
debris. Repeat cleaning process until the cloth is free of debris.
f. Dry the cylinder completely.
4. Coat all bare steel surfaces thoroughly with clean, 50-weight aviation oil to prevent
cylinder bore damage due to rust and contamination.

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 Engine Cleaning
12-1.2. Piston Cleaning
CAUTION: When utilizing compressed air, wear OSHA approved
safety glasses, goggles or face shield. Never exceed 30 psi when
using compressed gases for cleaning purposes. (OSHA 1910.242(b))
1. Soak the piston in mineral spirits.
2. If carbon deposits do not yield to solvent and deposits remain, install a tight fitting
skirt protector and dry blast the piston heads with soft grit or employ the vapor grit
method (to clean the piston top). Refer to Section 12-2, “Dry Blasting.” and
Section 12-3, “Vapor Blasting.”
WARNING
When dry blasting, do not use sand, glass, shot or metal grit
which can damage engine components. This media will become
embedded in aluminum parts rendering them unusable.
3. Clean the piston with hot, soapy water and a stiff bristled (non-wire) scrub brush to
remove all blasting materials from the piston. Thoroughly rinse all soap residue
from the piston and cylinder bore using hot water.
CAUTION: Do not use wire brushes or scrapers of any kind to clean
the piston.
4. Clean the piston ring grooves by pulling lengths of binder twine or very narrow
strips of crocus cloth through the grooves. Do not use automotive ring grooves
scrapers; the corner radii at the bottom of the grooves and side clearances must not
be altered. Do not use abrasive cloth on the piston skirts because the diameters and
cam-ground contour must not be altered.
5. Discard scored or burned pistons.
6. After cleaning, thoroughly rinse pistons using a Stoddard solvent to remove all
debris.

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Engine Cleaning
12-1.3. Cleaning Exhaust Parts
1. Clean the exhaust system parts (except for the multi-segment V-band clamps) with
Stoddard solvent. Allow the solvent to drain and wipe the parts dry with a clean
cloth.
2. Clean V-band clamps using crocus cloth on the outer band clamp assembly.
12-1.4. Cleaning Aluminum Alloy Parts
Degrease aluminum alloy parts with mineral spirits. Soak heavily soiled parts for 15
minutes in mineral spirits. To remove carbon and gum deposits, perform the following:
CAUTION: Do not use an alkaline etching solution.
1. Immerse the part in a hot bath of any of the following long enough to remove the
deposit:
a. Inhibited, mild alkaline cleaning solution.
b. Hot, soapy water.
c. Carbon solvent (only for hard, thick carbon deposits).
2. Remove the cleaned part from the solvent bath.
CAUTION: Remove all solvent residue (especially if soap or mild
alkaline cleaning solution is used), paying particular attention to
crevices, recesses, and holes to prevent engine oil contamination on
re-assembly. If not removed completely, the alkaline residue can
corrode the part.
3. Rinse thoroughly to remove all traces of the cleaning solution.
CAUTION: When utilizing compressed air, wear OSHA approved
safety glasses, goggles or face shield. Never exceed 30 psi when
using compressed gases for cleaning purposes. (OSHA 1910.242(b))
4. Dry the part with dry compressed air.
5. If carbon deposits remain on the part, refer to Section 12-2, “Dry Blasting.”
6. Remove protective seals and masking material.
7. If the Alodine finish was removed during cleaning, restore the alodine finish
according to Section 12-4.1, “Alodine.”

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 Engine Cleaning
12-2. Dry Blasting
Dry blast cleaning entails aiming plastic pellets or processed natural materials, such as
crushed walnut shells, under pressure toward an area to be cleaned. To clean using the dry
blast method, perform the following procedure:
WARNING
Do not use sand, glass, shot or metal grit when dry blasting as
this can damage engine components. This type of shot will
become embedded in aluminum parts rendering them useless.
CAUTION: Mask machined surfaces, such as bearing saddles, lifter
bores, and parting surfaces to avoid surface erosion or abrasion.
3Procedure
1. Prior to dry blasting any component, seal and protect all machined surfaces on the
holes and finished surfaces.
2. Using plastic pellets or processed natural materials, such as crushed walnut shells,
adjust blast pressure to the lowest setting that will produce the desired cleaning
action and aim toward the paint, varnish, or carbon deposit.
CAUTION: When utilizing compressed air, wear OSHA approved
safety glasses, goggles or face shield. Never exceed 30 psi when
using compressed gases for cleaning purposes. (OSHA 1910.242(b))
3. Blow off all dust with dry, compressed air.
4. Verify that no blasting material has lodged in crevices, recesses, or holes.
12-3. Vapor Blasting
Vapor blasting is used in specific, limited applications such as piston tops. This vapor
grit method of cleaning employs high-pressure steam and a very fine abrasive to remove
heavy carbon deposits. Clean parts thoroughly after vapor blasting to remove all traces
of the blast media.
CAUTION: Vapor blasting must not be used on bearing surfaces.
Follow the equipment manufacturer’s instructions when employing
this type of cleaning.

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Engine Cleaning
12-4. Protective Coatings
Protective or anti-corrosive coatings include:
• Alodine
• Zinc chromate primer
• Enamel paint
• 50-weight aviation oil
Apply a protective coating after any machining or repairing aluminum surfaces with an
aluminum conversion coating. Continental recommends alodine, also known by the brand
name Accelagold, to prevent corrosion on aluminum surfaces, see Section 12-4.1,
“Alodine.”
12-4.1. Alodine
Apply a protective coating of alodine to any of the following:
• Parts with aluminum surfaces that have been cleaned, machined, or repaired.
• Aluminum alloy castings
• Aluminum sheet metal
• Aluminum tubing
If the original aluminum conversion coating has been removed or deteriorated, it must be
restored. Apply Alodine or Accelagold solution in accordance with the manufacturer's
instructions. For Accelagold, refer to Technical Data Bulletin Number 108-31 Turcoat®
Accelagold Aluminum Conversion Coating.
12-4.2. Aviation Oil
Apply clean 50-weight aviation oil to cleaned, machined steel surfaces.

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 Engine Cleaning
12-4.3. Paint
1. Mask all connection joints and mating surfaces.
2. Clean the parts thoroughly with parts cleaning solvent to remove residue.
3. Determine the type of material the part is made of:
• Aluminum parts are lightweight, non-ferrous, gray colored metal.
• Steel and Iron parts are ferrous, meaning they respond to a magnet
• Magnesium parts resemble aluminum; non-ferrous, gray colored metal. To differ-
entiate between aluminum and magnesium, apply a few drop of vinegar to the
bare metal at a non-critical location on the part, such as a casting datum locator;
do not test at a mating surface. Aluminum will not react to vinegar, magnesium
will oxidize (bubble) and release hydrogen gas at the application site. Rinse the
part thoroughly to remove the vinegar residue.
CAUTION: Do not apply primer or enamel paint to internal engine
parts or any part that contacts the engine oil supply. The paint or
primer may flake or break off during engine operation and
contaminate the engine oil.
4. Follow instructions in Table 12-3 for instructions to prepare and apply protective
coatings to the exterior of the engine parts. Do not prime or paint internal parts or
interior surfaces of the engine.
Table 12-3. Painting External Parts
.

Aluminum Parts Ferrous Parts Magnesium Parts

1. Apply alodine according to 1. Apply zinc chromate primer. 1. Chrome pickle the part (AMS M-3171)
manufacturer’s instructions 2. Apply enamel to the parts. 2. Apply zinc chromate primer.
2. Apply enamel to the part. 3. Bake for 15 minutes using 3. Apply enamel to the part.
infrared heat or oven-dry for 60 4. Bake for 15 minutes using infrared heat or
minutes at 275 to 300F (135 oven-dry for 60 minutes at 275 to 300F (135
to 149C). to 149C).

Through Hardened Cylinder Barrels

Part No. 658601, or later
1. Apply zinc phosphate primer to cylinder barrel
only and allow to dry.
2. Apply one coat black enamel to cylinder
barrel.
3. Paint aluminum cylinder head according to
aluminum parts instructions.
4. Bake primed and painted cylinders for 16
hours in 400°F oven.

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Intentionally Left Blank

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 Glossary
Appendix A. Glossary
A-1. Abbreviations/Acronyms
The following acronyms are commonly used throughout Continental publications.

Abbreviation/Acronym Definition/Description
°C degrees Celsius
°F degrees Fahrenheit
Ω ohm
A or Amp Ampere
A&P Airframe & Power-plant
AD Airworthiness Directive
AFM Airplane Flight Manual
AO Authorized Oversize
APU Auxiliary Power Unit
AR As Required
AU Authorized Undersize
BHP Brake Horsepower
BSOC Brake Specific Oil Consumption
BTC Before Top Dead Center
CFM Cubic Feet per Minute
CHT Cylinder Head Temperature
CSB Critical Service Bulletin
DMM Digital Multimeter
DVM Digital Volt-ohm Meter
EGT Exhaust Gas Temperature
EMI Electromagnetic Interference
ft foot
ft. lbs. foot pounds
FAA Federal Aviation Administration
FAR Federal Aviation Regulations
FBO Fixed Base Operator
g gram
gal U.S. gallon
gph gallons per hour

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Glossary

Abbreviation/Acronym Definition/Description
HP Horsepower
IAW In accordance with
ICA Instructions for Continued Airworthiness
in. inch
in. Hg inches of Mercury
in. lbs. inch pounds
kg kilogram
kPa kilopascal
kW kilowatt
L liter
lb. pound
m meter
mm millimeter
MAP Manifold Air Pressure
MAT Manifold Air Temperature
MEK Methyl Ethyl Ketone
MHS Material Handling Specifications
MJ Main Journal
MSB Mandatory Service Bulletin
OAT Outside Air Temperature
OD Outside Diameter
OEM Original Equipment Manufacturer
NATO North Atlantic Treaty Organization
Nm Newton meter
POH Pilot’s Operating Handbook
PMA Parts Manufacturing Approval
P/N Part Number
ppm parts per million
psi pound per square inch
RMS Root Mean Square
RPM Revolutions per Minute
SB Service Bulletin

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 Glossary

Abbreviation/Acronym Definition/Description
SID Service Information Directive
SIL Service Information Letter
STANAG Standardization Agreement (STANAG)
STC Supplemental Type Certificate
TBO Time Between Overhauls
TC Type Certificate
TDC Top Dead Center
TIT Turbine Inlet Temperature
TSO Technical Standard Order
TSMOH Time Since Major Overhaul
WOT Wide Open Throttle

A-2. Terms and Definitions

Term Definition
Alternate Air System Should the inlet to the Air Induction system become blocked, the
alternate air system is designed to open providing air flow into the engine
cylinders to prevent air starvation.
Airworthiness Approval Tag FAA Tag 8130-3 that identifies a part or group of parts that has been
deemed airworthy by an authorized FAA representative.
Aneroid Metering Rod This rod is positioned by the aneroid and regulates fuel pump output
pressure based on ambient pressure or turbocharger discharge
pressure.
Burning In reference to the engine valves, indicates roughening or erosion due to
high temperature gases escaping past valve faces. In other instances, it
indicates drawing of the temper of steel parts to a soft (blue) condition, as
a result of overheating, during an absence of lubrication on moving
surfaces, such as gear teeth subject to high loading.
Burr Sharp or rough projection of metal.
Chafing Condition caused by a rubbing action between adjacent or contacting
parts under light pressure which results in wear.
Crack Partial separation of material usually caused by vibration, overloading,
internal stresses, improper assembly, or fatigue.

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Glossary

Term Definition
Critical Service Bulletin Service document based on determination by the product manufacturer
to constitute a threat to continued safe operation of an aircraft or to
persons or property on the ground unless the owner or operator takes
some specific action (inspection, repair, replacement, etc.). Documents in
this category are candidates for incorporation into an Airworthiness
Directive issued by the FAA.
Dent Rounded depressed, pushed-in area on a surface.
Dynamic Seal Vital seal in the engine cylinder that consists of valve-to-valve seat seals,
spark plug-to-spark plug port seals, and cylinder head-to-barrel seal.
Elongate To stretch out or lengthen.
Erosion Wearing away of material due to flow, hot gases, grit, or chemicals.
Fretting Surface erosion caused by slight movement between two parts that are
fastened together.
Fuel Control Unit A mechanically controlled valve that meters the amount of fuel based on
throttle position.
Fuel Manifold Valve A device that distributes metered fuel flow to the individual cylinder fuel
injector nozzles. It also serves as a positive idle cut-off valve whenever
the engine is shut down.
Fuel Metering Unit Controls the amount of fuel flow to the Manifold valve assembly based on
throttle position.
Fuel Pressure Regulator A device that regulates full power fuel pressure without restricting
maximum fuel pressure at lower power settings.
FULL RICH Position of the mixture control that is required for Take off and full power
settings. This setting provides the maximum ratio of parts fuel to parts air.
(See Mixture Control)
Galling Severe chafing or fretting that results in transfer of metal from one part to
another; usually caused by slight movement of mated parts that have
limited relative motion and are under heavy loads.
Grooved Surface Shallow channels, ider than scratches and usually smooth resulting
from wear affected by concentrated contact stress.
Hot Weather Ambient temperature exceeding 90°F (32°C)
Hydraulic Lock Condition where fluid accumulates in the induction system or the cylinder
assembly. The liquid restricts the piston from traveling during the
compression stroke. Damage to the engine occurs when the other
cylinders fire, which forces the piston in the fluid-filled cylinder through
the compression stroke. Damage to an engine from hydraulic lock can be
extensive due to the extreme stress load and can adversely affect
connecting rods, pistons, cylinder assemblies, piston pins, the
crankcase, and the crankshaft.

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 Glossary

Term Definition
Idle Cut-off Position of the mixture control that will virtually shut off the flow of fuel to
the engine. (See Mixture Control)
Mandatory Service Bulletin Service document relating to known or suspected hazards to safety that
have been incorporated in whole or in part into an Airworthiness Directive
(AD) issued by the FAA, or have been issued at the direction of the FAA
by the manufacturer requiring compliance with an already-issued AD (or
an equivalent issued by another country’s airworthiness authority).
Naturally Aspirated A non boosted engine. Utilizes atmospheric pressure for combustion.

Nick Sharp-sided gouge or depression with a V-shaped bottom.

Peening Series of blunt depressions in a surface.
Pitting Formation of pockets of corrosion products on the surface of a metal.
Propeller Strike Any incident that requires repair (other than minor dressing of the blade)
to a propeller blade. Either the propeller strikes an object or an object
strikes the propeller and causing a propeller imbalance. Propeller strikes
are serious because they can result in engine failure. Even if the
propeller still continues to rotate, other components critical to engine
operation may be damaged.
Runout Eccentricity or wobble of a rotating part; eccentricity of two bored holes or
two shaft diameters; a hole or bushing out of square with a flat surface.
Runout is usually measured with a dial indicator, and limits stated
indicate full deflection of indicator needle in one revolution of part or
indicator support.
Scoring Deep grooves in a surface caused by abrasion from fine hard particles
wedged between moving surfaces, as in a bearing and journal, or caused
by galling when a moving part is not supplied with lubricant.
Service Bulletin Service document that contains information considered by the product
manufacturer to constitute a substantial improvement to the inherent
safety of an aircraft or component of an aircraft; also includes updates of
instructions for continued airworthiness.
Service Information Directive Service document that contains information determined by the
manufacturer to be of value to an owner/operator in the use of a product
by enhancing safety, maintenance, or economy.
Service Information Letter Service information document may be useful to the owner/operator/
technician. May contain updates to Instructions for Continued
Airworthiness for optional component installations, which are not covered
in the Applicable Operator, Maintenance, or Overhaul Manuals.
Spall (Spalling) Distress to a loaded surface where chips of the hardened surface are
broken out.
Static Seal Cylinder seal that consists of the piston rings to the cylinder wall seal.

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Glossary

Term Definition
Technical Standard Order FAA-designated number and identification mark indicating that the part or
appliance meets applicable design standards and was manufactured in
accordance with the requirements of FAR 21 Subpart O.
Throttle The air throttle controls the flow of air to the engine, depending on the
position of the throttle control lever in the aircraft cockpit. Fuel control
units are attached to the throttle control to permit the flow of fuel to be
controlled as the throttle controls the airflow.
Thru Bolt (Thru-Bolt) aka Through Bolt

Unmetered Pressure Pressure of the fuel in pounds per square inch (PSI) at the outlet of the
engine driven fuel pump or inlet of the fuel control unit.
Upper Deck Pressure Upper Deck Pressure is also referred to as turbocharger compressor
discharge pressure. This is the pressure in inches of mercury in the
induction system after the turbocharger compressor and before the
throttle plate.

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 Torque Specifications
Appendix B. Torque Specifications
B-1. General Information
NOTE: For TIARA engines, refer to the primary ICA (Section 1-1.1) for
torque specifications.
Tables in this appendix list torque values for Continental engine hardware. For aircraft or
engine accessory torque specifications, refer to the aircraft or accessory manufacturer’s
instructions.
Table B-1. Appendix B, Quick Table Reference
.

Table Number and Title Page No.

Table B-2. Component Specific Torque Specifications1 B-6

Table B-3. Specific Torque Specifications (Non-Lubricated Hardware)2 B-13

Table B-4. FADEC Components (Non-Lubricated Hardware)2 B-13

Table B-5. General Torque Specifications (for bolts, nuts, screws, driving B-14
studs, and pipe plugs)
Table B-6. Hydraulic Line Torque Specifications B-14
Table B-7. Straight Thread Fitting Torque Specifications3 B-15
Table B-8. Hose Fitting (“B” Nut) Torque Specifications B-15
1. Torque values provided in Table B-1 must be used for the listed applications.
2. Table B-2 and Table B-3 lists specific “non-standard” torque values.
3. Table B-6 includes tube fittings.

WARNING
Torque values listed are for use with clean 50 weight aviation
engine oil applied to the threads, unless otherwise specified in
Table B-3 or Table B-4, which list torque specifications for non-
lubricated hardware.
Confirm items identified in Appendix C-2.3, “100% Parts Replacement Requirements” or
Appendix C-2.4, “Mandatory Overhaul Replacement Parts”(at overhaul) are replaced
prior to assembly. Prior to torquing any hardware, unless otherwise specified, apply SAE
50 weight aviation oil to hardware listed in Table B-5 through Table B-8. If an application
is not listed in the specific torque limits tables (Table B-2 through Table B-4), use the
general torque limits in Table B-5 through Table B-8.
WARNING
Proper torquing practices cannot be over emphasized. Torque
procedures are provided to achieve correct preloading of
fasteners. If the fasteners are not properly plated, the fastener
threads are not clean and free of deformation or are not properly
lubricated, the correct fastener preload will not be achieved even
though the given torque value is reached. For this reason, it is
critical that all fasteners be inspected for proper plating, thread
form, and correctly lubricated prior to torquing. Failure to

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15 Sep 2019
Torque Specifications
verify a fastener's serviceability or to correctly lubricate the
fastener prior to assembly and torquing will result in the
fastener not being properly preloaded and subsequent failure of
the fastener may occur.
B-1.1. Torque Tips
WARNING
Do not apply any form of sealant to the crankcase cylinder
deck, chamfer, cylinder mounting flange, cylinder base O-ring,
or cylinder fastener threads. The use of RTV, silicone, Gasket
Maker or any other sealant on the areas listed above during
engine assembly will cause a loss of cylinder deck stud or
through-bolt torque. Subsequent loss of cylinder attachment
load, loss of main bearing crush and/or fretting of the
crankcase parting surfaces will occur. The result will be
cylinder separation, main bearing movement, oil starvation and
catastrophic engine failure. USE ONLY CLEAN 50 WEIGHT
AVIATION ENGINE OIL ON SURFACES LISTED.
• Check Table B-2 and Table B-4 first to determine if the hardware to be torqued
requires a specific torque or treatment other than those for general torque
specifications listed in Table B-5 through Table B-8.
• Before installing hardware, verify the fastener size is correct.
• The accuracy of any torque indicating wrench depends on a smooth application of
force and current calibration traceable to the National Institute of Standards and
Technology (NIST), verifiable by the calibration data label affixed to the tool.
• If cotter pin holes must be aligned, set the torque wrench at the low limit and tighten
the nut to the first hole beyond this torque, but do not exceed the maximum specified
torque limit. This torquing procedure must be followed for all applications requiring
cotter pin hole alignment except for connecting rod nuts.
• If a nut slot cannot be aligned with a cotter pin hole within the specified limits,
substitute another serviceable nut to attain alignment.
• If the cotter pin hole in a stud lies beyond the nut slots, when the nut has been torqued
properly, check the stud for proper installation or for backing out.
• Check studs for necking damage (over stretch/misshapen deformity) due to
excessively applied torque.
• Check the part for reduced thickness resulting from wear or incorrect part.
• Where applicable, special instructions/details are provided in footnotes following each
table.
• The notation (AR) refers to “As Required” in all torque specification tables.

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 Torque Specifications
B-2. Part Supersedure
1. Through bolt nuts Part Nos. 634505 and 649496 have been superseded by nut Part
Number 652541. At engine overhaul, all Part Number 634505 and 649496 flanged
through bolt nuts must be replaced with Part Number 652541 (flanged 12 point nut).
NOTE: If replacing Part Number 634505 or 649496 (less that a complete
set, prior to engine overhaul), torque the replacement nut Part Number
652541 to the required valve of the original fasteners (Part Number
634505 or 649496).
a. Nut, Part Number 634505 is a flanged 6 point (hex) nut requiring a torque value
of 690-710 inch lbs.
b. Nut, Part Number 649496 is a flanged 6 point (hex) nut requiring a torque value
of 790-810 inch lbs.
c. Nut, Part Number 652541 is a flanged 12-point nut requiring a torque value of
790-810 inch lbs.
2. Connecting Rods
a. Nut, Connecting Rod (nut Part Number 626140 w/bolt Part Number 35972) is
superseded by Nut, Connecting Rod (Spiralock nut Part Number 654487 w/bolt
Part Number 655960).
b. Nut, Connecting Rod (nuts 24804 or 626140 w/bolt Part Number 530213) and
Nut, Connecting Rod (Spiralock nut Part Number 654487 w/bolt Part Number
654693) are superseded by Nut, Connecting Rod (Spiralock nut Part Number
654487 w/bolt Part Number 655959).

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Torque Specifications
B-3. Torque Wrench and Extension Calculations
Torque wrenches measure the force applied to the fastener on the axis of the square drive
socket adapter.

Square
Drive

Force
Torque Setting/Reading = Force x Distance
Torque Wrench Square Drive Distance = A

Figure B-1. Torque Wrench

Straight extensions and wobble extensions up to 15 degrees, which extend the square drive
length, do not alter the amount of force applied to the square drive enough to cause
concern. An offset adapter may be used with a torque wrench without affecting applied
torque if the extension is positioned at a 90 degree angle in relation to the square drive
adapter (ref, Figure B-2). In any other orientation, the extension alters the adjusted torque
wrench setting (force) applied to the fastener.

90°

90°

Set Torque = Fastener Torque

15°

If angle ≤ 15°
Set Torque = Fastener Torque

Figure B-2. Drive Extensions

Apply the formula below to determine the adjusted torque wrench setting (S, inch-pounds)
when using an extension (ref. Figure B-4(+, increases) or Figure B-5(-, decreases)):

T Where:
S = -------------------xA S = adjusted torque wrench setting, inch-pounds
A  B T= “torque” applied at square drive adapter
A= torque wrench handle length, inches
B= (±) extension length, inches

Figure B-3. Adjusted Torque Wrench Setting

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 Torque Specifications
Examples in Figure B-4 and Figure B-5 illustrate how extensions can alter the torque
applied at the fastener.
• The example in Figure B-4 adds the length of the extension to the torque wrench,
increasing the leverage applied to the fastener.
• The position of the extension in Figure B-5 reduces the effective length of the handle and
leverage. Variable B (length of the extension) is subtracted from variable A.
Assume the torque wrench has an effective length of 12 inches and the extension measures
six inches from the center of the drive adapter to the center of the wrench. To “torque” the
nut and bolt to 45 inch-pounds (T), determine the adjusted torque wrench setting (S), use
example:
• Figure B-4, 30 inch-pounds = (45 ÷ (12 + 6)) x 12
• Figure B-5, 90 inch-pounds = (45 ÷ (12 - 6)) x 12

Extension Torque Wrench Square Drive Distance = A

Length = B
Fastener Torque Distance

Fastener Torque
Set Torque= A+B xA

Extension Torque Wrench Square Drive Distance = A

Length = B
Fastener Torque Distance

Figure B-4. Extension, Increases Adjusted Torque Wrench Setting

Torque Wrench
Square Drive Distance = A

Extension
Length = B Fastener Torque
Set Torque= A-B xA

Figure B-5. Extension, Decreases Adjusted Torque Wrench Setting

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Torque Specifications
Table B-2. Component Specific Torque Specifications
Torque Value
Models Affected (Non-standard, see
Size Fastener In.-Lbs. Ft.-Lbs. General Torque Specification)

Crankcase
.25-28 Nut, Crankcase Flange 100-125 8.3-10.4 A, C, & E Series, O-200, O-300, 
O-470 (AR), XX-240, XX-360
.25-28 Nut, Engine Mount Leg 90-100 7.5-8.3 C-125, C-145 & O-300
Bushing
.25-28 Nut, Tie Bolt Prop Shaft Cages 90-110 7.5-9.2 GO-300
.31-18 Bolt, Oil Sump Flange 155-175 12.9-14.6 IO-346, XX-470, XX-520 & XX-550
.31-24 Nut, Crankcase Flange 180-220 15.0-18.3 IO-346, XX-470, XX-520 & XX-550
.31-24 Nut, Crankcase Backbone 240-280 20.0-20-3 (AR) Stainless Steel Hardware Only
.31-24 Nut, Crankcase Through Bolts 180-220 15.0-18.3 O-470 (AR), & E Series
.31-24 Nut, Magneto to Crankcase 100-120 8.3-10.0 All Models (AR)
.31-24 Nut, Magneto Gearshaft 190-210 15-8-17.5 XX-360
Support to Crankcase,
ConeLok
.31-24 Nut, Self-Locking, Fuel Pump 155-175 12.9-14.6 O-200-A, B & D; O-300-A & D
Cover
.38-24 Bolt, Crankcase Through Bolts, 275-325 22.9-27.1 GO-300
Front Main Only
.38-24 Nut, Crankcase Through Bolts, 370-390 30.8-32.5 O-470 & E Series
Front
.38-24 Nut, Crankcase Through Bolts, 275-325 22.9-27.1 All XX-470, XX-520 & XX-550
Upper Rear
.38-24 Nut, Crankcase Through Studs 275-325 22.9-27.1 A Series, C-75, C-85, C-90 & O-200
.38-24 Nut, Crankcase Tie Bolts 370-390 30.8-32.5 All (AR) EXCEPT XX-240 & XX-360
.38-24 Nut, Crankcase Tie Bolts 275-325 22.9-27.1 All XX-240 & XX-360
.38-24 Nut, Cylinder to Crankcase 410-430 34.2-35.8 A, C, & E Series, O-200, O-300, GO-300 &
Stud O-470
.38-24 Nut, Cylinder to Crankcase 440-460 36.7-38.3 All XX-240 & XX-360
Studs
.38-24 Nut, Mounting Bracket to 275-325 22.9-27.1 All Models (AR)
Crankcase
.44-20 Nut, Crankcase Tie-Bolts-Nose 440-460 36.7-38.3 All Models (AR)
& Below Camshaft
.44-20 Nut, Cylinder to Crankcase 490-510 40.8-42.5 All Models EXCEPT TSIOL-550
Studs (includes 7th stud)
.44-20 Nut, Cylinder to Crankcase 590-610 49.2-50.8 TSIOL-550
Studs
.44-20 Nut, Cylinder to Crankcase 400-450 33.3-37.5 A Series, C-75, C-85 & C-90
Through Studs
.44-20 Nut, Front & Rear Crankcase 490-510 40.8-42.5 O-200, O-300
Bearing Through Studs

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 Torque Specifications
Table B-2. Component Specific Torque Specifications
Torque Value
Models Affected (Non-standard, see
Size Fastener In.-Lbs. Ft.-Lbs. General Torque Specification)
.44-20 Nut, Through Bolt at Cadmium 440-460 36.7-38.3 All Models (AR)
Plated Washer
.44-20 Nut, Through Bolt at Cylinder 490-510 40.8-42.5 All (AR) EXCEPT XX-240 & XX-360
Flange
.44-20 Nut, Through Bolt at Cylinder 590-610 49.2-50.8 All XX-240 & XX-360
Flange
.44-20 Nut, Through Bolt at Front 490-510 40.8-42.5 All Models (AR)
Mount Belt-Driven Alternator
.44-20 Nut, Tie Bolts at Nose and 340-360 28.3-30.0 GO-300
Prop Shaft Cages
.50-20 Nut, Crankcase Through Bolt 615-635 51.2-52.9 IO-346, XX-470, XX-520 & XX-550
at Cadmium Plated Washer
.50-20 Nut, Crankcase Through Bolt 690-710 57.5-59.2 All IO-346, All 470, All 520 & All 550 
at Cylinder Flange, P/N EXCEPT TSIOL-550
634505 (6 point/0.33” tall)
.50-20 Nut, Crankcase Through Bolt 790-810 65.8-67.5 All IO-346, All 470, All 520 & All 550 
at Cylinder Flange, P/N EXCEPT TSIOL-550
652541 (12 point)
.50-20 Nut, Crankcase Through Bolt 790-810 65.8-67.5 TSIOL-550
at Cylinder Flange, P/N
649496 (6 point/0.43” tall)
.50-20 Nut, Crankcase-Nose Tie Bolts 640-660 53.3-55.0 All Models (AR)
.50-20 Nut, Through Bolt at Cadmium 690-710 57.5-59.2 TSIOL-550
Plated Washer
.62-18 Plug, (using crush washer) 190-210 15.8-17.5 All Models (AR)

Gears
.25-28 Bolt, Gear to Camshaft 140-160 11.7-13.3 A, C & E Series, O-200, O-300, O-470, 
XX-240
.25-28 Bolt, Gear to Crankshaft  140-160 11.7-13.3 A, & C Series, O-200, XX-240, O-300 &,
(P/N 22532)1 GO-300
.25-28 Bolt, Gear to Crankshaft  170-175 14.2-14.6 E Series, O-470 Numerical, O-470-A & E
(P/N 534904)1
.31-24 Bolt, Gear to Camshaft 240-260 20.0-21.7 E Series, XX-360, IO-346,
XX-470, XX-520 & XX-550
.31-24 Bolt, Gear to Crankshaft 240-260 20.0-21.7 E Series, XX-360, IO-346
(Lower Hardness Identified
with Green Dykem)1
.31-24 Bolt, Gear to Crankshaft (Bolt 380-420 31.7-35.0 XX-470, XX-520 & XX-550
Hardness RC 38-42) 1
.31-24 Bolt, Face Gear to Crankshaft 140-150 11.7-12.5 IO-346, XX-520 (AR), XX-550
.31-24 Nut, Generator or Alternator 175-200 14.6-16.7 A, C & E Series, O-200, IO-240, O-300,
Gear GO-300 & XX-360

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Torque Specifications
Table B-2. Component Specific Torque Specifications
Torque Value
Models Affected (Non-standard, see
Size Fastener In.-Lbs. Ft.-Lbs. General Torque Specification)
.31-24 Nut, Generator Gear (531231) 175-195 14.6-16.3 E Series
w/washer (401507)
.38-24 Bolt, Vacuum & Fuel Pump 275-325 22.9-27.1 XX-240
Gear to Camshaft
.38-24 Nut, Slick Mag Gear to 120-180 10.0-15.0 O-200 & O-300
Magneto Shaft
Connecting Rods
.38-24 Nut, Connecting Rod  400-475 33.3-39.6 A & C Series, O-200, XX-240, 
(nuts 24804 or 626140  O-300, GO-300 & XX-360
w/bolt P/N 530213)2, 3, 4
.38-24 Nut, Connecting Rod  400-475 33.3-39.6 E-Series O-470, IO-470, with 654796
(Spiralock nut P/N Connecting Rod
LINKED654487
w/bolt P/N 655960)
.38-24 Nut, Connecting Rod  400-475 33.3-39.6 E-185, E-205, E-225, IO-346, O-470
(nut P/N 626140 w/bolt P/N Numbered and Lettered Engines IO-470,
35972)2, 3, 5 TSIO-470, with 628751 Connecting Rod
.38-24 Nut, Connecting Rod 490-510 40.8-42.5 O-200, XX-240, O-300, XX-360 & XX-470
(Spiralock nut P/N 654487 
w/bolt P/N 654693)5
.38-24 Nut, Connecting Rod 490-510 40.8-42.5 O-200, XX-240, O-300, XX-360 & XX-470
(Spiralock nut P/N 654487 
w/bolt P/N 655959)
.44-20 Nut, Connecting Rod 550-600 45.8-50.0 O-470, IO-470, IO-520, L/TSIO-520-AE &
(Spiralock nut P/N 643215  CE, IO-550, IOF-550, TSIO-550, 
w/bolt P/N 643112) TSIOF-550 & TSIOL-550
.44-20 Nut, Connecting Rod 690-710 57.5-59.2 O-470, IO-470, GTSIO-520, IO-520, 
(Spiralock nut P/N 654490  L/TSIO-520, IO-550, IOF-550, TSIO-550,
w/bolts P/N 643112 or P/N TSIOF-550 & TSIOL-550
655958)
.44-20 Nut, Connecting Rod (rod P/N 690-710 57.5-59.2 O-470, IO-470, GTSIO-520, IO-520, 
655004 or 655005 w/bolt P/N L/TSIO-520
655961 and Spiralock nut P/N
654490)
.44-28 Nut, Connecting Rod 475-525 39.6-43.8 IO-346, O-470, IO-470, TSIO-470, IO-520
(rod P/N 646476 w/bolts & TSIO-520 (EXCEPT L/TSIO-520-AE &
P/N 629340 and nut 628109)2 CE)
.44-28 Nut, Connecting Rod 550-575 45.8-47.9 GTSIO-520
(rod P/N 646474 w/bolts
P/N 631794 and nut 631554) 2

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 Torque Specifications
Table B-2. Component Specific Torque Specifications
Torque Value
Models Affected (Non-standard, see
Size Fastener In.-Lbs. Ft.-Lbs. General Torque Specification)
Miscellaneous Fuel Injection
#8-32 Screw, Aneroid Body Hold 17.5-22.5 1.5-1.9 All Fuel Injected Model (AR)
Down (AN500-8-14)
#8-32 Screw, Manifold Cover Hold 22-26 1.8-2.2 All Fuel Injected Model (AR)
Down (AN503-8-12)
.125-27 Fitting, Cover, Fuel Pump, 60-80 5.0-6.7 All Fuel Injected Model (AR)
Vapor Separator
.125-27 Nozzle, Fuel Injector  55-65 4.6-5.4 All Fuel Injected Model (AR)
(w/anti-seize compound)
.19-24 Through Bolt, Fuel Pump 29-31 2.4-2.6 All Fuel Injected Model (AR)
.25-28 Ejector, Cover, Fuel Pump, 90-100 7.5-8.3 All Fuel Injected Model (AR)
Vapor Separator
.25-48 Jam Nut, Aneroid Stem 25-30 2.1-2.5 All Fuel Injected Model (AR)
Adjustment
.31-24 Nozzle, Fuel Injector  55-65 4.6-5.4 All Fuel Injected Model (AR)
(w/anti-seize compound)
.31-24 Nut, Throttle and Mixture 100-120 8.3-10.0 All Fuel Injected Model (AR)
Control Levers to Shaft
.31-32 Nut, Fuel Injection Line 40-45 3.3-3.7 All Fuel Injected Model (AR)
.38-24 Nut, Fuel Injection Line 55-60 4.6-5.0 All Fuel Injected Model (AR)
.50-24 Nut, Air Reference Sleeve “B” -- -- All Turbocharged Models
Nut to Air Reference Line 6

.62-18 Metering Unit Plug & Screen 120-130 10.0-10.8 All Fuel Injected Model (AR)
Assembly (w/new gasket)

Miscellaneous Lubrication System Fasteners

.25-20 Bolt, Oil Cooler to Adapter 100-110 8.3-9.2 XX-360, XX-470, XX-520 (AR), & XX-550
.25-20 Bolt, Oil Pump Cover to 75-85 6.3-7.1 All Models (AR)
Crankcase
.25-28 Nut, Collar Assembly - 75-85 6.3-7.1 XX-470, XX-520 (AR), & XX-550
Governor Oil Transfer
.375-18 Oil Cooler Cross Fitting7 185 min. 15.4 min. TSIO-550-C, K, N; TSIOF-550-D, K
.38-24 Tachometer, Shaft to Oil Pump 280-300 23.3-25.0 XX-360
Drive Gear
.62-18 Plug, Bypass Valve 190-210 15.8-17.5 O-200-D
.62-18 Plug, Oil Cooler  190-210 15.8-17.5 All Models (AR)
(w/crush washer)
.62-18 Plug, Oil Suction Tube  190-210 15.8-17.5 All Models (AR)
(w/crush washer)
.62-18 Plug, Oil Sump Drain 190-210 15.8-17.5 All Models (AR)
.62-18 Oil Filter Cartridge 180-216 15.0-18.0 All Models (AR)

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Torque Specifications
Table B-2. Component Specific Torque Specifications
Torque Value
Models Affected (Non-standard, see
Size Fastener In.-Lbs. Ft.-Lbs. General Torque Specification)
.75-16 Oil Filter, Disposable 192-216 16.0-18.0 All Models (AR)
.75-16 Plug, Oil Sump Drain 190-210 15.8-17.5 IO-470-M & IO-520-E
.88-16 Cap, Oil Relief Valve 190-210 15.8-17.5 O-200, XX-240, O-300 & XX-360
.88-16 Plug, Oil Bypass 240-260 20.0-21.7 XX-470, XX-520 (AR), & XX-550
1.00-14 Vernatherm, Oil Temperature 190-210 15.8-17.5 All Models (AR)
Control Valve8
1.00-18 Screen Assembly, Scavenge 200-210 16.7-17.5 O-300 (AR) & XX-360 (AR)
Oil
1.12-18 Housing, Oil Pressure Relief 240-260 20.0-21.7 IO-346, XX-470, XX-520 (AR), & XX-550
Valve (New Gasket)
1.25-18 Plug, Special Vernatherm 310-320 20.8-29.2 XX-470, XX-520 (AR), & XX-550 (AR)
1.25-18 Vernatherm, Oil Temperature 410-420 34.2-35.0 All Models (AR)
Control Valve8
1.375-16 LH Housing, Tachometer Drive 250-350 20.8-29.2 All Models (AR)
1.75-16 Oil Filter Adapter Lock Nut 500-520 41.6-43.3 O-300 (AR) & XX-360 (AR)
1.75-16 Oil Filter Screen (w/new crush 500-520 41.6-43.3 All Models (AR)
gasket. Install gasket w/parting
line against screen face.)
Miscellaneous Cylinder Hardware
.071 (18mm) Spark Plug 9 300-360 25.0-30.0 All Models (AR)
.125-27 Connector, Cylinder Drain 60-80 5.0-6.7 All Models (AR)
.19-32 Screw, Cylinder Baffle to Baffle -- -- All Models (AR)
Support10
.19-32 Screw, Cylinder Baffle to Baffle 36-50 3.0-4.2 All Models (AR)
Base
.25-20 Bolt, Rocker Shaft Hold Down 85-110 7.1-9.2 O-470-2, 4, 13, 13A & O-470-B (AR)
.25-20 Bolt, Through Bolted Rocker 90-100 7.5-8.3 XX-470, IO-520, TSIO-520 (EXCEPT BE),
Shaft IO-550 (EXCEPT G, N, P & R), IOF-550
(EXCEPT N, P & R) & TSIOL-550
.25-20 Screw, Rocker Box Cover 55-65 4.6-5.4 XX-240 & XX-360
(tighten two lower screws first)
.25-20 Screw, Rocker Cover 55-65 4.6-5.4 All Models (EXCEPT 240 & 360)
.25-20 Screw, Intake Flange 85-110 7.1-9.2 All Models (AR)
.25-20 Set Screw, Rocker Shaft, 45-55 3.8-4.6 O-200, O-300
Locking
.25-28 Nut, Rocker Shaft Hold Down 110-120 9.2-10.0 XX-240 & XX-360
.25-28 Nut, Exhaust (self locking) 120-130 10.0-10.8 All Models (AR)
.25-28 Nut, Exhaust Manifold Flange 100-110 8.3-9.2 All Models (AR)
(spirotallic gasket)

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 Torque Specifications
Table B-2. Component Specific Torque Specifications
Torque Value
Models Affected (Non-standard, see
Size Fastener In.-Lbs. Ft.-Lbs. General Torque Specification)
.31-18 Bolt, Rocker Shaft Hold 190-210 15.8-17.5 GTSIO-520, TSIO-520-BE, IO-550-G, N, P
Down11 & R, IOF-550-N, P & R, TSIO-550 &
TSIOF-550
.31-24 Bolt, Rocker Shaft Hold 85-110 7.1-9.2 XX-470, IO-520, TSIO-520 (EXCEPT BE),
Down12 IO-550 (EXCEPT G, N, P & R), IOF-550
(EXCEPT N, P & R) & TSIOL-550
.31-24 Nut, Exhaust Manifold Flange 200-210 16.7-17.5 All Models (AR)
(spirotallic gasket)
.31-24 Nut, Induction Tube Flange 50-70 4.2-5.8 XX-240 & XX-360
.44-20 Plug, Cylinder Drain  50-70 4.2-5.8 TSIOL-550
(w/O-ring)

Miscellaneous Fasteners
.19-32 Nut, Carburetor Air Intake Box 9-10 0.75-0.83 O-200-D
Control Lever
.25-62 Clamp, Hose, Oil Gauge Rod 12-16 0.3-1.3 XX-360(AR)
.25-62 Clamp, Hose, Magneto 10-14 0.8-1.17 All Models with Pressurized Magnetos
Pressurization
.25-28 Nut, Exhaust Coupling,  42 3.5 TSIO-520-L, LB & WB
“V” band clamp 13

.31-18 Bracket, Turbocharger 220-250 18.3-20.8 GTSIO-520-F, K

.31-18 Bolt, Alternator Mounting 150-180 12.5-15.0 IO-346, All 520 & All 550
.38-16 Bolt, Turbocharger to Bracket 310-350 25.8-29.2 TSIO-520-L1, LB, UB, WB
.38-24 Nut, Slick Mag Impulse 120-180 10.0-15.0 All Model using Slick Impulse Coupled
Coupling to Magneto Shaft Magnetos
.38-24 Nut, Starter to Adapter 200-220 16.7-18.3 O-300 (AR), GO-300 (AR), IO-346, 
All 470, 520 & 550
.44-20 Nut, Alternator Sheave to 600-720 50-60 TSIO-520-B
Starter Shaft
.56-18 Nut, Starter Shaft Gear14 450-500 37.5-41.6 IO-520 & XX-550
.56-18 Nut, Starter Jaw, Crankshaft 575-625 47.9-52.1 O-470-Numeral
.56-18 Nut, Generator Pulley Drive 450-500 37.5-41.7 IO-346, ALL 470, IO-520, TSIO-520, 
XX-550
.56-24 Screw, Shoulder,  800-850 66.6-70.8 TSIO-520-BE, TSIO-550, TSIOF-550
Air Conditioning Idler Sheave
.62-32 Nut, Alternator Hub Assembly 300-450 25.0-37.5 IO-346, IO-520(AR), TSIO-520 (AR),
GTSIO-520 (AR), XX-550
.66-20 Nut, Alternator or Generator 450-500 37.5-41.7 O-470, IO-470, IO-520 (AR), TSIO-520
Pulley (AR), XX-550

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Torque Specifications
Table B-2. Component Specific Torque Specifications
Torque Value
Models Affected (Non-standard, see
Size Fastener In.-Lbs. Ft.-Lbs. General Torque Specification)
.75-16 Nut, Starter Shaft Gear, --- 180-220 GTSIO-520
Viscous Damper
.88-18 Adapter, Tachometer 120-180 10.0-15.0 XX-240 & XX-360
Reduction Gear
1. Heat crankshaft gear to 300º F; install gear on crankshaft immediately for shrink fit. Ensure the gear seats tightly against the end of the
crankshaft by tapping lightly with a brass hammer.
2. Torque to low limit. If cotter pin will not align with holes, increase torque gradually, up to high limit only. If cotter pin holes will not align within
torque range, replace the nut and repeat. In no case shall nuts be tightened below the minimum or above the maximum torque limit.
3. A) P/N 530184 connecting rod (identified by forging number 530186), P/N A35159 (identified by forging 5561) and P/N A35160 (also identi-
fied by forging number 5561) require a drilled bolt (was P/N 530213), castellated nut (was P/N 24804 or 626140) and P/N 639292 cotter
pin. P/N 530213 and 626140 are obsolete. If new stock is unavailable, replace the connecting rod assemblies..
B) Assemble P/N A36121 connecting rods utilizing the P/N 632041 forging with the part numbers indicated in current technical data.
Assemble P/N A36121 connecting rod assemblies utilizing the P/N 40742 forging require a drilled connecting rod bolt (P/N 359724), castel-
lated nut (P/N 24804) nut and P/N MS24665-132 cotter pin. If new stock is unavailable, replace the connecting rod assemblies.
4. Bolt P/N superseded by 655960. Do not mix with obsolete parts.
5. Bolt P/N superseded by 655959. Do not mix with obsolete parts.
6. Snug nut finger tight to set seal between nut and male connector, then tighten additional 3/4 to 1 turn.
7. Install fitting hand-tight. Wrench tighten the cross fitting to the appropriate clocking of fitting within 1-3 turns from the finger tight position.
Minimum torque of 185 in/lbs must be achieved upon clocking position of fitting. The fitting is not to be loosened in order to achieve proper
alignment (clocking).
8. Apply Continental P/N 646943. Option - 646943-1
9. Lubricate spark plug threads with spark plug manufacturer’s recommended lubricant.
10. Install baffle screw until seated against flat washer; then, tighten an additional 2-6 turns. Baffle to be snug but not distorted. Verify minimum
one (1) thread protrudes past nut plate on lower cylinder baffle.
11. Do not realign hex cap screw to mate with tab washer.
12. Must be reworked to through-bolt rocker shaft configuration according to most current revision of Continental Service Document M92-6.
13. Strike outer periphery of coupling band lightly to distribute load. Tighten to 50-60 in.-lbs. for P/N 641284 clamp and 60-70 in.-lbs for P/N
653832 clamp.
14. Align and adjust compressor belt tension according to most current revision of Continental Service Document M89-6.

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 Torque Specifications
Table B-3. Specific Torque Specifications (Non-Lubricated Hardware)
Torque Value
Size Fastener In.-lbs. Ft.-lbs. Models Affected
--- Clamp, Hose (Worm Gear) 25-35 2.0-2.9 All Models (AR)
#8-32 Screw, Throttle Lever 17.5-22.5 1.5-1.9 All Models (AR)
#10-32 Nut, Magneto Ground Terminal 15-17 1.25-1.41 Continental S-20/200, S-
1200 Magnetos
#10-32 Nut, Magneto Ground Terminal 13-15 1.08-1.25 Slick Magnetos
#10-32 Screw, Ignition Harness Cable Outlet Plate 12-15 1.0-1.25 Continental S-20/200
Magnetos
Various Nut, Ignition Harness Cable Outlet Plate 18-22 1.5-1.8 Continental S-1200
Magnetos
Various Screw, Ignition Harness Cable Outlet Plate 18-28 1.5-2.33 Slick Magnetos
.125-27 Fuel Injector Nozzle to Cylinder1 55-65 4.6-5.4 All Fuel Injection Models
.31-24 Nut, Cable Attach 55-60 4.6-5.0 All w/Energizer Starter
.31-32 B-Nut, Fuel Injection Line to Fuel Injector Nozzle 40-45 3.3-3.8 All Models (AR)
.375-24 B-Nut, Fuel Injection Line to Fuel Manifold Valve 55-60 4.6-5.0 All Non-FADEC Fuel
Injected
.56-24 Sensor, Magneto (Tachometer) 35-40 2.9-3.3 All Models (AR)
.625-24 B-Nut, Ignition Lead to Spark Plug 90-95 7.5-7.91 All Non-FADEC
.68-24 Sensor, Magneto (Tachometer) 35-40 2.9-3.3 All Models (AR)
.75-20 B-Nut, Ignition Lead to Spark Plug 110-120 9.2-10.0 All Non-FADEC
1.12-18 Oil Pressure Relief Valve Housing 240-260 20.0-21.7 All Models (AR)
1. Apply Continental P/N 646943 Anti-Seize Lubricant

Table B-4. FADEC Components (Non-Lubricated Hardware)

Torque Value
Size Fastener In.-lbs. Ft.-lbs. Models Affected
#4 Screw, ECU 50-Pin Connector 10-15 0.83-1.25 All FADEC
#4 Screw, Speed Sensor 25-Pin Connector 10-15 0.83-1.25 All FADEC
#10 Bolt, Ground Strap 25-35 2.02.9 All FADEC
.125-27 Adapter Fitting, Manifold Air Temperature 60-80 5.0-6.6 All FADEC
.25-18 NPT Sensor, Fuel Pressure 130-150 10.83-12.5 All FADEC
.25-18 NPT Sensor, Manifold Pressure 130-150 10.83-12.5 All FADEC
.25-24 Bolt, ECU Mount 60-70 5.0-5.83 All FADEC
.25-.62 Clamp, Exhaust Gas Temperature Sensor 30-35 2.5-2.9 All FADEC
.31-32 Nut, Fuel Injection Solenoid Retaining 24-28 2.0-2.3 All FADEC
.375-24 Bayonet Adapter, Cylinder Head Temp. Sensor 55-65 4.58-5.41 All FADEC
.375-24 Fuel Injection Line to Fuel Distribution Block 55-60 4.6-5.0 All FADEC
.437-24 Compression Fitting, Manifold Air Temp. Ferrule 145-155 12-12.9 All FADEC
.75-20 B-Nut, Ignition Harness to Spark Tower 110-120 9.1-10.0 All FADEC
.75-20 Jam Nut, ECU Spark Tower 110-120 9.1-10.0 All FADEC

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Torque Specifications

Table B-5. General Torque Specifications

Bolts, Nuts, Screws
Torque
Size In. lbs. Ft. lbs.
#2-56 1.4-2.6 N/A
#4-40 2.9-5.5 N/A
#6-32 5.3-10.1 N/A
#8-32 17.5-22.5 1.5-1.9
#10-32 36-50 3.0-4.2
#10-24 21-25 1.7-2.0
.250-20 75-85 6.3-7.1
.250-28 90-100 7.5-8.3
.3125-18 155-175 12.9-14.6
.3125-24 180-220 15.0-18.3
.375-16 220-260 18.3-21.7
.375-24 275-325 22.9-27.1
.44-20 400-450 33.3-37.5
.50-20 550-600 45.8-50.0
Driving Studs
.250-20 50-70 4.2-5.8
.3125-18 100-150 8.3-12.5
.375-16 200-275 16.7-22.9
.44-14 300-425 25.0-35.4
Pipe Plugs
.062-27 30-40 2.5-3.3
.125-27 60-80 5.0-6.7
.250-18 130-150 10.8-12.5
.375-18 185-215 15.4-18.0
.500-14 255-285 21.3-23.8
.750-14 310-350 25.8-29.2

Table B-6. Hydraulic Line Torque Specifications

Hose Size Hose End Fitting Material Torque (In.-lbs.) Models Affected
.44-20 Nut-Self-Locking #4 hose 115-165 TSIO-520-L, LB, WB
.56-18 Nut-Self-Locking #6 hose 185-335 TSIO-520-L, LB, WB
.75-16 Nut-Self-Locking #8 hose 360-570 TSIO-520-L, LB, WB

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 Torque Specifications
NOTE: Fitting torques in Table B-7 shall not be used for tapered fittings.
For tapered (NPT/NPTF) fittings that must be oriented to a specific angle
(clocked) for mating with another fitting or hose, screw the fitting into the
port finger-tight. Wrench tighten additional 2-3 turns until the fitting is
oriented at the desired angle. Do not loosen the fitting to achieve proper
alignment.
Table B-7. Straight Thread Fitting Torque Specifications
Size Fitting Size Torque (In.-lbs.)
.31-24 Brass / Aluminum 15-30
.31-24 Steel 15-50
.38-24 Brass / Aluminum 40-65
.38-24 Steel 50-90
.44-20 Brass / Aluminum 60-80
.44-20 Steel 70-120
.44-24 Steel 60-80
.56-18 Brass / Aluminum 75-125
.56-18 Steel 90-150
.75-16 Brass / Aluminum 150-250
.75-16 Steel 135-250
.88-14 Brass / Aluminum 200-350
.88-14 Steel 300-400

Table B-8. Hose Fitting (“B” Nut) Torque Specifications

Hose Size Hose End Fitting Material Torque (In.-lbs.)
-2 (.31-24) Brass/Aluminum Fitting 50-80
-2 (.31-24) Steel Fitting 75-120
-3 (.38-24) Brass/Aluminum Fitting 70-105
-3 (.38-24) Steel Fitting 95-140
-4 (.4375-20) Brass/Aluminum Fitting 100-140
-4 (.4375-20) Steel Fitting 135-190
-5 (.500-20) Brass/Aluminum Fitting 130-180
-5 (.500-20) Steel Fitting 170-240
-6 (.5625-18) Brass/Aluminum Fitting 150-195
-6 (.5625-18) Steel Fitting 215-280
-8 (.750-16) Brass/Aluminum Fitting 270-350
-8 (.750-16) Steel Fitting 470-550
-10 (.875-14) Brass/Aluminum Fitting 360-430
-10 (.875-14) Steel Fitting 620-745
-12 (1.063-12) Brass/Aluminum Fitting 460-550
-12 (1.063-12) Steel Fitting 855-1055

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Torque Specifications

Intentionally Left Blank

B-16 Standard Practice Maintenance Manual

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 Maintenance Standards
Appendix C. Maintenance Standards
C-1. Handling Parts
When removing, replacing, or reinstalling parts, heed the following precautions, warnings,
and tips:
WARNING
Turn the Ignition Switch OFF and disconnect engine electrical
power before commencing maintenance or inspections.
Confirm continuity between the magneto capacitor and aircraft
ground to prevent accidental engine start during maintenance.
Do not stand or place equipment within the arc of the propeller.
• If the engine is installed, disconnect engine electrical (battery) power and verify the
Ignition Switch is turned OFF. Confirm continuity between the magneto capacitor and
aircraft ground before commencing engine maintenance.
• Inspect replacement parts for deterioration or wear. Do not install parts that appear worn,
deteriorated, or beyond published (service or overhaul) limits.
• Prevent safety wire, nuts, washers, dirt, etc. from entering the engine.
• If any foreign object accidentally falls into the engine, stop working on the engine
immediately and retrieve the dropped object(s).
• Tag unserviceable parts or units for investigation and possible repair.
• To ensure proper reinstallation of usable parts, tag or mark all parts and hardware as they
are removed or disassembled.
• Use protective caps, plugs, and covers to ensure openings are unexposed. Install dust caps
over the tube ends of open lines and NOT IN the tube ends. Be sure to remove the dust
caps and covers after the maintenance or repair work is complete.
• Cover stored engine sub-assemblies.
• Inspect new parts for transit damage. Do not install damaged or non-conforming parts.
Re-seal or rewrap the new part until the part is ready to be cleaned, prepared, and
installed.
• Check the shelf life of new parts to be installed. Do not install parts with an expired shelf
life.
• Thoroughly clean parts according to the instructions in Chapter 12.
• Use only a plastic or rawhide mallet made to tap engine parts during assembly; never use a
hammer.
• Always install new gaskets, o-rings, rubber components, seals, packing, cotter pins, tab
washers, safety wire, and lock washers when servicing components.
• Use only new, shake proof or split lock washers, tab washers, elastic stop nuts, cotter pins,
and corrosion-resistant safety wire.
• Do not replate cadmium-plated fasteners or washers. If the cadmium plating has been
removed, discard the item and replace it with a new part.
• Do not reinstall any worn, deformed, or single use fasteners.

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Maintenance Standards
• Torque hardware to Appendix B torque specifications.
WARNING
Do not apply any form of sealant to the crankcase cylinder
deck, chamfer, cylinder mounting flange, cylinder base O-ring,
or cylinder fastener threads. The use of RTV, silicone, Gasket
Maker or any other sealant on the areas listed above during
engine assembly will cause a loss of cylinder deck stud or
through-bolt torque. Subsequent loss of cylinder attachment
load, loss of main bearing crush and/or fretting of the
crankcase parting surfaces will occur. The result will be
cylinder separation, main bearing movement, oil starvation and
catastrophic engine failure. USE ONLY CLEAN 50 WEIGHT
AVIATION ENGINE OIL ON SURFACES LISTED.
• Before installing nuts and bolts, verify the fastening hardware is lubricated according
to instructions in Chapter 3 and Appendix B instructions. Inspect all fasteners for
proper plating and thread form. Failure to verify a fastener’s serviceability or to
correctly lubricate the fastener as instructed prior to installation will result in the
fastener not being properly preloaded. Subsequent fastener failure may occur.

C-2 Standard Practice Maintenance Manual

15 Sep 2019
 Maintenance Standards
C-2. Replacement Parts
C-2.1. Background
An increasing amount of replacement parts (including standard parts), materials,
appliances, and instruments are represented as being of aircraft quality when actually the
quality and origin of these units is unknown. Users of such units are usually not aware of
the potential hazards involved with replacement parts that are not eligible for use on
certified aircraft. Frequently, such units are deceptively advertised or presented as
“unused,” “like new,” or “remanufactured,” implying the quality of such units is equal to
an original or appropriately repaired or overhauled unit.
The performance rules for replacement of parts and materials used in the maintenance and
alteration of U.S.-certified aircraft are specified in Title 14 Code of Federal Regulations
(CFR)§§ 21.9.
C-2.2. Acceptable Replacement Parts
Continental provides Instructions for Continued Airworthiness (ICAs) based on the
design, testing, and certification of engines and parts for which Continental is the holder
of the Type Certificate (TC) or Parts Manufacture Approval (PMA) issued by the Federal
Aviation Administration (FAA). These instructions, which include maintenance, repair
limits, overhaul, and installation are applicable only to engines and parts supplied by
Continental. Continental does not provide instructions relating to the installation or use of
parts not manufactured or supplied by Continental. Instructions provided by other engine
parts manufacturers or resellers should be used for their parts. Continental has not
participated in design, test, or certification in regards to aftermarket parts manufacturers
and has no experience with respect to such parts.
FAA regulations require only FAA-approved parts be used on a type certified product.
FAA-approved parts may be identified in accordance with the information given below.
Continental does not play any role in the FAA approval of such parts; does not have any
responsibility for the design, certification, service life, repair, overhaul, or quality of such
parts; and has made no determination regarding the effect, if any, that using such parts
may have on Continental supplied engines or parts.
C-2.2.1. Know Your Supplier
Some reproduced parts and components, particularly instruments, have been
manufactured by entities other than the original equipment manufacturer and are available
for purchase and installation on U.S.-certified aircraft. Often, an original part is used as a
sample to produce duplicates. The reproduced parts appear to be as good as the original
part. However, there are many unknown factors to be considered that may not be readily
apparent to the purchaser, such as heat-treating, plating, inspections, tests, and
calibrations. All too often, the faulty part is not discovered until a malfunction or an
accident occurs.
Therefore, in accordance with federal aviation regulations, certification of materials, parts,
and appliances for aircraft return to service is the responsibility of the person or agency
who signs the approval. The owner/operator is responsible for the continued airworthiness
of the aircraft. To ensure continued safety in aircraft operation, it is essential that great
care be used when inspecting, testing, and determining the acceptability of all parts and
materials. Particular caution should be exercised when the identity of materials, parts, and
appliances cannot be established or when their origin is in doubt.

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Maintenance Standards
C-2.3. 100% Parts Replacement Requirements
“100% Replacement” parts are items that require a “new” replacement if removed during
any maintenance or preventive maintenance on the engine or it’s components. You must
always replace removed gaskets, seals, packings, hoses, “O” rings, cotter pins, retaining
rings (snap rings), safety wires, self locking fasteners (including exhaust and connecting
rod nuts) and lock washers with “new” serviceable parts.
NOTE: Service documents published or revised subsequent to the
issuance of this publication may mandate the replacement of components
and parts not included in these instructions. At engine overhaul, the
technician must review all service bulletins to ensure compliance with the
manufacturer’s requirements for continued airworthiness.
Do not re-use worn, damaged or deformed fasteners. Do not replate cadmium plated
fasteners or washers. If the cadmium plating has been removed, discard the item and
replace it with a new part.
Engine mounted accessories must be maintained in accordance with the manufacturer’s
instructions. Additionally, accessories must be overhauled during engine overhaul, or
more frequently, in accordance with the manufacturer’s instructions.
At engine overhaul the starter, starter adapter, alternator, magnetos, and engine fuel system
must be replaced with New, Factory Rebuilt, or FAA approved overhauled units. On
turbocharged engines, the turbocharger, wastegate, all controllers, bypass valve and
exhaust system must be replaced with new, factory rebuilt or FAA approved overhauled
units. All engine baffles must be repaired or replaced and all flexible baffle seals replaced.
Items such as spark plugs, alternator drive belts and air-conditioning drive belts are
replaced on condition.

C-4 Standard Practice Maintenance Manual

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 Maintenance Standards
C-2.4. Mandatory Overhaul Replacement Parts
In addition to the items listed in Section C-2.3, mandatory replacement parts must be
discarded and replaced with new parts during engine overhaul.
Table C-1. Mandatory Overhaul Replacement Parts
MANDATORY
REPLACEMENT
SPECIAL 100% AT ENGINE
REPLACEMENT ITEMS CONDITIONS REPLACEMENT OVERHAUL
Replace On
Accessories, Engine Mounted1 Condition
X
Replace On
Air-conditioning Drive Belts X
Condition
Alternators
• Drive Belts Replace On X
• Rubber Drive Bushings Condition X
Baffles (see Engine Baffles) Repairable X
Bearings: connecting rod, crankshaft main and thrust, needle, ball, and roller X
Bushings: used in bearing applications (subject to wear) - reference disassembly/
X
assembly instructions
Camshaft Gears:
• Replace P/Ns 535934, or 535660, or 656037 (O470J, K, L, R, S; IO346A; IO470J, Design
X
K) with 656913, or subsequent part number, at overhaul. Change
• Replace P/Ns 537432 or 656038 (O470G, GCI, M; IO470C, D, E, F, H, L, M, N, S; Design
TSIO470B, C, D; GTSIO520C, D, H, K, L, M, N, R) with 656914, or subsequent part X
number, at overhaul. Change
• Replace P/Ns 631845, or 655516, or 656031 (O470U, IO470U, V; IO520A, B, BA,
BB, C, CB, D, E, F, J, K, L, M, MB, N, NB, P, R; LIO520P; L/TSIO520ALL; Design
IO550ALL; IOF550ALL; TSIO550ALL; TSIOL550A, B, C), or 655430 (IO550A, B, C, X
Change
D, E, F, G, L, N) with P/N 656818 or subsequent part number)
Camshaft Gear Bolts X
Cold Start Primer Diverter Valves X
Inspection
Connecting Rods (must be inspected for serviceable condition during Overhaul)
Required
• Connecting Rods (P/N 626119, 646320, and 646321 must be replaced with current Design
X
part number)2 See Section 10-9.1 for engine applicability Change
• Connecting Rods (with beam widths less than 0.625 inches must be replaced with Design
X
current part number)2 Change
• Connecting Rod Bolts X
• Connecting Rod Nuts X
Cotter Pins X
Counterweight
Design
X X
• Counterweights (P/N 631810 must be replaced with P/N 652833)3 Change
• Counterweight Pins X
• Retainer Plates X
• Retaining (Snap) Rings X
Crankcase Through Bolts X
Crankshaft Gears
• Crankshaft Gear (P/Ns 536421 or 653631 must be replaced with P/N 657175, or Design X
subsequent)3 Change
• Crankshaft Cluster Gear (P/Ns 641906 or 656272 must be replaced with P/N Design X
656072, or subsequent)4 Change
• Crankshaft Gear, large (P/N 656991 Rev B must be replaced with P/N 656991 Design X
Rev.C, or subsequent)5 Change
• Crankshaft Gear Bolts X

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Maintenance Standards
Table C-1. Mandatory Overhaul Replacement Parts
MANDATORY
REPLACEMENT
SPECIAL 100% AT ENGINE
REPLACEMENT ITEMS CONDITIONS REPLACEMENT OVERHAUL
Crankshaft Gears, continued
• Crankshaft Alternator Face Gear Bolts X
• Crankshaft Alternator Face Gear Lock Plates X
Cylinder Deck Stud Nuts and Through Bolt Nuts X
Engine Baffles (see Baffles) Repairable X
Replace On
Engine Mounted Accessories1 Condition
X
Exhaust Nuts X
Exhaust Valves and Rotocoils X
FADEC X
• Electronic Control Units X
• Engine Low Voltage Harness (including EGT and CHT sensors) X
• Fuel Filter X
• Fuel Injectors X
• Fuel Pressure Sensors X
• Manifold Air Pressure Sensors X
• Oil Pressure Sensor, if equipped X
• Oil Temperature Sensor, if equipped X
• Signal Conditioner, if equipped X
• Speed Sensor X
• Turbine Inlet Temperature Sensor(s), if equipped X
Replace On
Filters, replaceable (air, oil, fuel, magneto), if equipped X
Condition
Flexible Baffle Seal X
Fuel Systems X
Fuel Pump Drive Coupling (P/N 631263 must be replaced with P/N 653359, or
subsequent part number)6 on all IO520B, BA, BB, C, CB, M, MB, N, NB; TSIO520B, BB, Design
X
BE, D, DB, E, EB, J, JB, K, KB, L, LB, N, NB, UB, VB, WB; IO550A, B, C, G, N, P, R; Change
TSIO550A, B, C, E; TSIOL550A, B, C
Gaskets X
Replace On
Hoses X
Condition
Hydraulic Lifters (tappets) X
Ignition System Harness X
Replace On
Intake Valves
Condition
Lock Washers X
Magnetos X
• Magneto Rubber Drive Bushings X
“O” Rings X
Design
Oil Pump Gears (O-300, IO-360, TSIO-360 and LTSIO-360 Series)7 Change
X
Oil Suction Screens (360 series P/Ns 649470, 649471, 652669, 652670 must be Design
X
replaced with current part number)7 Change
Oil Suction Screens (C-125, C-145 and O-300 series P/N 633272 must be replaced with Design
X
current part number)7 Change
Packings X
Pistons X
• Pins X
• Rings X

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 Maintenance Standards
Table C-1. Mandatory Overhaul Replacement Parts
MANDATORY
REPLACEMENT
SPECIAL 100% AT ENGINE
REPLACEMENT ITEMS CONDITIONS REPLACEMENT OVERHAUL
Intake Valve Rotocoils (except all E-series, O-470, IO-470, IO-520 / 550, TSIO-520 / 550 Design
X
TSIOL-550 and GTSIO-520 engines)8 Change
Rocker Shafts X
Rocker Shaft Thrust Washers X
Rotocoils, Exhaust X
Safety Wire X
Seals X
Self Locking Nuts X
Snap Rings X
Solid Valve Spring Retainers X
Replace On
Spark Plugs X
Condition
Starter4 X
Design
• Starter Adapter Assemblies (replace all GTSIO520 with EQ6642)9 Change
X
Turbochargers X
• All Controllers X
• Bypass Valve X
• Exhaust Clamps X
• Exhaust System X
• Oil Supply Valves X
• Return Check Valves X
• Snap Rings X
• Wastegate X
Valve Keepers (intake/exhaust) X
Valve Springs (inner/outer) X
10 X
Woodruff Keys
1. Engine mounted accessories must be maintained and overhauled at engine overhaul, or more frequently, in accordance with the
manufacturer’s instructions.
2. Reference Critical Service Bulletin CSB96-13 (or latest revision)
3. Reference Section 10-9.1 (was SB00-3) for Permold engine models. For Sandcast engines, replace crankshaft gear according to
instructions in SB08-12.
4. Reference Service Bulletin SB14-2 (or latest revision)
5. Reference Service Bulletin SB13-6 (or latest revision)
6. Reference Mandatory Service Bulletin MSB 95-6 (or latest revision)
7. Reference Service Bulletin SB96-4 (or latest revision)
8. Replace intake valve rotocoils with solid valve spring retainers on all E-series O-470, IO-470, IO-520/550, IOF550, TSIO-520/550, TSIOL-
550, TSIOF550, and GTSIO-520 engines.
9. Reference Service Bulletin MSB94-4 (or latest revision). Overhaul is prohibited on starter adapters with scavenge pump, P/N 658440. On
GTSIO-520; all EQ6642 starter adapter assemblies (both new and factory rebuilt) include new torsional damper, starter adapter shaftgear,
and crankshaft gear.
10. Reference the manufacturer’s primary ICAs for all alternators.

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Maintenance Standards
C-2.5. Authorized Oversize/Undersize Parts
Replacement “authorized oversized” (AO) or “authorized undersized” (AU) parts must be
used with the proper AO and AU mating parts. Example: use 0.015 oversize piston and
piston rings with 0.015 oversize cylinder assembly.
C-2.6. Special Instructions
It is recommended that a new or factory rebuilt replacement EQ6642 kit be installed
during any prop strike/sudden engine stoppage inspection for all GTSIO-520 engine
models.
C-2.7. Engine Data Plate Replacement
The engine data plate is intended to remain with the engine throughout its service life. On
occasion, an engine data plate may be damaged, stolen, or lost.
For Rolls Royce Engines manufactured under license from Continental:
1. The new data plate does not alter the original certification basis of the engine.
2. The engine model will retain the original RR- prefix in the engine designation.
3. The engine will retain the data from the original Rolls Royce serial number and
Type Certificate number issued by the CAA.
C-2.7.1. Removal and Installation of Engine Data Plate
Please refer to 14 CFR part 45.13 and latest revision of AC45-3 prior to removing or
installing an engine data plate. Replacement engine data plates are available from the
manufacturer, if the following conditions are met:
1. Request must be in writing
2. Request must be coordinated through the nearest FAA office (or equivalent
airworthiness authority), with written endorsement as specified in Title 14 CFR
45.13, paragraph (b) and (d).
3. If the engine data plate has been lost or stolen, or if a removed data plate is being
retained by the airworthiness authority, the requestor must obtain written
certification from the airworthiness authority on official letterhead verifying the
engine model number and serial number of the engine from which it was removed.
4. Unless step 3 above applies, the original data plate must accompany the written
request for the replacement data plate.
5. Enclose a check or money order payable to Continental Aerospace Technologies, in
the amount of $300.00 (Three Hundred Dollars, U.S. Funds).
6. Submit request to:
Continental Aerospace Technologies
P.O. Box 90
Mobile, AL 36601
ATTN: Customer Service Department

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 Maintenance Standards
C-2.7.1.1. Data Plate Removal
The engine data plate is secured to the crankcase with single use, rivet-like fasteners,
called drive screws.
CAUTION: Do not mar or damage the crankcase during the
replacement procedure.
1. Carefully insert a wide blade gasket scraper between the data plate and the
crankcase adjacent to each drive rivet. As the data plate is lifted, the drive screw
should release from the crankcase.
2. Repeat step 1 for each of the five remaining drive screw rivets. Discard the drive screws.
C-2.7.1.2. Data Plate Installation
1. Check the alignment of the new data plate with the existing holes in the crankcase.
a. If the crankcase is new, follow the instructions in this section, step 2.
b. If the existing drive screw holes do not align, follow the instructions in this
section, step 3
2. If the existing drive screw holes align with the new data plate:
a. Install a drill stop at a depth of 0.19 inch on a #51 (0.067 inch dia.) drill bit.
Install the drill bit in a hand drill.
b. Drill the existing six screw holes slightly oversize with the #44 drill bit to a depth
of 0.19 inch.
c. Clean the aluminum shavings from the crankcase.
d. Fasten the data plate to the right side of the crankcase (side with either #1-3 or
#1-3-5 cylinders) with six each new P/N 21007 drive screws.
3. If the existing drive screw holes do not align with the new data plate:
a. Patch the existing holes with 3M Part Number 1838, “Scotch Weld” structural
adhesive, or Loctite Part Number 44581, “Fast Cure” epoxy.
b. Install a drill stop at a depth of 0.19 inch on a #51 (0.067 inch dia.) drill bit.
Install the drill bit in a hand drill.
c. Use the data plate as a template, mark the center of the new holes.
d. Drill the six drive screw holes to a depth of 0.19 inch.
e. Clean the aluminum shavings from the crankcase.
f. Fasten the data plate to the right side of the crankcase (side with either #1-3 or
#1-3-5 cylinders) with six each new P/N 24764 drive screws.

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Maintenance Standards
C-3. Safety Wiring Hardware
Safety wiring secures two or more parts together so any tendency of the parts to loosen
will be counteracted by increasing the tension on the safety wire attached to the other
part(s). Remove safety wire to loosen the fasteners. Never reuse safety wire; always use
new safety wire to secure hardware. Safety wire on these engines must conform to
MS20995 Condition A.
1. Verify the hardware (bolts or nuts) to be safety wired has been correctly torqued to
Appendix B specifications.
CAUTION: Do not apply torque above or below specified limits to
align holes.
2. Insert half of the required length of new safety wire through the first piece of
hardware and do the following:
a. For right-hand threaded hardware, install the safety wire so the strand will pull
and lock clockwise.
b. For left-hand threaded hardware, install the safety wire so the strand will pull and
lock counter-clockwise

Figure C-1. Right-Hand Thread Safety Wire Installation

(Reverse application for left hand threads)

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 Maintenance Standards
3. As shown in Figure C-1, bend the safety wire to tightly loop around the head of the
hardware so force is exerted in the tightening direction. Ensure there is no slack in
the loop and the loop is under the protruding strand that will wrap around the
opposing piece of hardware to ensure the loop is held in place on the first device.
Pull the protruding strand of safety wire with pliers until it is taut (but not
overstressed).
4. While keeping the protruding strand of safety wire taut, twist the strands (based on
the wire gauge specified below) until the twisted part is just short of a hole in the
next unit. The twisted portion should be within one-eighth (1/8) inch from the hole
in either unit:
a. Twist 0.032” diameter safety wire at a rate of 7 to 10 twists per inch.
b. Twist smaller diameter safety wire at a rate of 9 to 12 twists per inch.
5. Pull the braided safety wire strand with pliers until it is taut (but not overstressed).
6. Insert the uppermost strand through the hole in the second piece of hardware.
7. Bend and wrap the twisted wire braid around the second piece of hardware, pulling
the wire taut as described in the previous steps, which will counter-lock the
hardware joined by the safety wire. Repeat the previous steps for any subsequent
hardware to be safety wired by this strand. Refer to Figure C-2 for various safety
wire patterns. All safety wire must fit snugly.
8. After safety wiring the last piece of hardware, continue twisting the safety wire to
form a pigtail, providing sufficient twists (four minimum) to ensure the pigtail will
not unravel.
CAUTION: Do not allow the safety wire pigtail to extend above the
bolt head.
9. Trim excess safety wire and bend the pigtail toward the hardware and against the
bolt head flats.

Figure C-2. Safety Wire Patterns for Right-Hand Threads

(Reverse the wire orientation for left-hand threads)

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Maintenance Standards
C-4. Tab Washer Installation
Tab washers are used in various locations on Continental engines. Do not re-use tab
washers. Always install new tab washers.
1. Insert the locator tab (bent part of the tab washer) in the pre-drilled hole.
2. Lubricate and torque hardware to Appendix B specifications.
CAUTION: Repositioning the fastener after torque application to
align the tab washer with the flat portion of the nut or bolt is
prohibited.
3. Using a soft drift, bend the lock tab on the other side of the tab washer firmly against
the bolt (or nut) flats as shown in Figure C-3. Ensure the lock tabs are bent flat up
against the hardware without protrusion as shown in top and side views to properly
lock the hardware and prevent the lock tabs from breaking off.

Locator Tab

Lock Tab
Lock Tabs
Top View Side View

Figure C-3. Tab Washer Installation

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 Maintenance Standards
C-5. Heli-Coil® Insert Replacement
Helical coil inserts are made of wire with a diamond-shaped cross section forming both a
male and female thread. Heli-coil® inserts are factory-installed in various tapped holes of
some engine components. Stainless steel heli-coil inserts of special design are installed in
all spark plug holes.
Tools, inserts, and information are available through Heli-Coil, Stanley® Engineered
Fastening (formerly Emhart Teknologies). The latest revision of the manufacturer’s
bulletins 959A, 995, 943, T4000, and 1000 list manual and power-driven installing tools,
tang break-off tools, special taps, plug gauges, and tap/drill information.
Heli-coil inserts are available in both National Course and National Fine series in lengths
equal to 1, 1½, and 2 times nominal diameter and in pipe thread sizes. They are made of
carbon steel, phosphor bronze, or stainless steel, as specified by part number. They are
supplied with or without a notch above the driving tang. The notch is provided to facilitate
breaking off the tang in open holes.
When compressed into a special tapped hole at the widest part of the wire between male
and female threads, the diameter of the insert is equal to the nominal screw size. The
special finishing taps size the threaded hole to allow the pitch diameter of the female
thread of the installed insert to conform to Class 3 fit with standard bolt threads or Class 4
(tight) fit with standard-size studs. The difference in fit is due to a difference in pitch
diameters of bolts and studs.
Only one set of heli-coil special taps is required for installing these inserts in both bolt
holes and stud holes. Tap drilling depths and tapping depth for heli-coil inserts to be
installed in blind holes must conform to the recommendations relative to inserts of length
equal to 2 times nominal diameter, as tabulated in the latest revision of the manufacturer’s
bulletin numbers 1000 and T4000.
Run heli-coil tap drills and special taps perpendicular to the machined surface to follow
the alignment of the existing hole.
For drilling and tapping aluminum alloy castings, use a commercial-grade cutting
lubrication oil to prevent overheating of the metal and tearing of the thread.
Heli-coils are prohibited in certain areas; verify that a heli-coil repair for a certain area is
approved prior to installing the heli-coil.
Replace heli-coils in approved areas when they are damaged in accordance with the
manufacturer’s instructions.

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Maintenance Standards
C-5.1. Heli-Coil Removal
1. Use the proper size extracting tool (Figure C-4) for the nominal thread size.
2. Tap the extracting tool into the heli-coil insert until the sharp edges of the tool dig
firmly into the heli-coil insert.
3. Turn the tool to the left and back out the heli-coil until it is free.

Figure C-4. Heli-Coil Extraction Tool

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 Maintenance Standards
C-5.2. Heli-Coil Insertion
1. Blow all debris and liquid out of the tapped hole.
2. Use a proper size installation tool and slide the new heli-coil insert over the slotted
end of the driving mandrel of the tool.
3. Engage the driving tang (bent end) of the heli-coil in the mandrel slot.
4. Wind the insert slowly into the tapped hole (as shown in Figure C-5).
5. The outer end of the insert must lie within the first full thread of the hole.
6. Break off the driving tang of a notched heli-coil by bending it back and forth across
the hole with long, needle nose pliers or with a special tang break-off tool.
7. Once the heli-coil insert is installed, the remaining wall thickness (edge distance) to
the heli-coil must not be less than one half the heli-coil diameter or 0.08 inches,
whichever is greater.
WARNING
On the crankcase, the 2 and 4 o'clock cylinder deck stud
positions must not be repaired by heli-coil insert installation.

Figure C-5. Installing a Helical Coil Insert

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Maintenance Standards
C-6. Stud Replacement
Studs that are damaged or broken must be replaced. Rosan® ring-locked studs, which were
previously installed in the cylinder exhaust ports have been replaced with standard
stainless steel studs. These Rosan studs are either “size-on-size” or “step type.” When
replacing studs, consult the illustrated parts catalog for the most current cylinder
configuration.
NOTE: Rosan lock ring exhaust studs have been superseded by stainless
steel studs on the Gold Standard cylinder configuration. If the existing
cylinders are fitted with Rosan lock ring studs, they may be replaced at
overhaul with the appropriate size Rosan studs. Do not replace stainless
steel studs with Rosan lock ring studs.
The step type captive lock ring studs have a larger lock ring than the size-on-size type. The
size-on-size captive lock ring studs utilize a small external diameter lock ring for
applications where edge distance is a factor. The lock ring is so small in diameter that the
use of a typical Rosan “SM” or “BT” series-milling tool is impractical and could cause
unwanted removal of cylinder head material in the lock ring area.
C-6.1. Stud Removal
For “Rosan Size-on-Size” stud removal, refer to the instructions in Section C-6.1.1. To
remove “Rosan Step-Type” stud, refer to the instructions in Section C-6.1.2.
For standard stud removal:
1. Place a standard stud extractor tool on the stud to be removed and turn the tool
slowly to avoid heating the casting.
2. If the stud cannot be removed with a standard stud extractor tool:
a. Drill a hole matching the diameter of a splined stud extractor tool through the
center of the stud.
b. Insert the splined stud extractor through the drilled hole and unscrew the stud.
3. Before discarding the damaged stud (above), measure the coarse-thread end to
determine the correct stud size for the replacement stud.
C-6.1.1. Size-on-Size Rosan® Stud Removal
To prevent damage to the engine cylinder, take precautions when removing a Size-on-Size
Rosan stud.
1. Carefully cut the damaged stud flush with the cylinder head. Do not come in contact
with or mark the cylinder head.
2. Score the remaining portion of the stud with a center punch.
3. Locate the proper size primary removal drill directly over the center of the stud and
drill to the specified depth. The primary removal drill size and specified depths are
listed in Table C-2.
4. Center the secondary removal drill over the small hole and drill to the depth
specified in Table C-2. This method should cut the engagement between the stud
serrations and the internal serrations of the lock ring.

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 Maintenance Standards

Table C-2. Rosan® Stud Primary & Secondary Bore Specifications

Cylinder Exhaust Port Stud Primary Removal Drill Secondary Removal Drill
Diameter Minimum Diameter (+0.015)
Basic Stud Number (inches) Depth (inches) Depth
(0.164 dia.) SFC164 1/16 (0.062) 0.250 3/16 (0.188) 0.080
(0.190 dia.) SFC190 1/16 (0.062) 0.250 7/32 (0.219) 0.090
(0.250 dia.) SFC250 3/32 (0.093) 0.250 19/64 (0.296) 0.105
(0.312 dia.) SFC312 1/8 (0.125) 0.312 R (0.339) 0.120
(0.375 dia.) SFC375 1/8 (0.125) 0.375 13/32 (0.406) 0.120
5. The remaining lock ring will have a very thin wall. Carefully use a sharp punch to
break away the remaining portion from the cylinder head.
6. Drive an “Ezy-Out®” bolt extraction tool into the small hole in the stud and apply
removal torque.
7. Remove the stud and clean the hole.
C-6.1.2. Step-Type Rosan® Stud Removal
There are two methods for removing Step-Type Rosan studs. Each method is described below:
C-6.1.2.1. Step-Type Rosan® Stud Removal, Method 1
1Procedure
1. Use the Rosan Stud Removal Tool (Figure C-6) to mill the lock ring to the
appropriate depth.
2. Apply removal torque to remove the stud.
3. Lift out the remaining portions of the lock ring.
4. Carefully use a sharp punch to break away the remaining portion from the cylinder head.

Rosan Removal Tool

Figure C-6. Rosan® Stud Removal

(shown with Removal Tool installed on stud)

C-6.1.2.2. Step-Type Rosan® Stud Removal, Method 2

1. Follow the procedure in Section C-6.1.1, “Size-on-Size Rosan® Stud Removal.”
2. Select the appropriate removal drill sizes with regard to the stud end dimension.
EXAMPLE:To remove a step-type stud with a 0.250-inch diameter nut
end and a 0.312- inch diameter stud end, use the appropriate removal drill
for a 0.312-inch “size-on-size” stud.

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Maintenance Standards
C-6.2. Stud Installation
Standard studs may be replaced using the instructions in this section. For “Rosan® Stud
Installation”, refer to instructions in Section C-6.2.1.
1. Standard studs have no marking. Refer to the table below to determine the proper
stud size required or to identify oversize studs.

Figure C-7. Stud Sizes

2. Clean the casting tapped hole with solvent and blow dry any debris or liquid out of
the hole using compressed air.
3. Examine the thread. If it is not torn, obtain the next larger oversize stud. If the old
stud was of the maximum oversize or if the thread is damaged, tap the hole and
insert a heli-coil insert according to instructions in Appendix C-5.2.
WARNING
Heli-coils can only be installed where authorized.

Figure C-8. Minimum Material Thickness for Helical Coil insertion

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 Maintenance Standards
4. A heli-coil insert can be used on a cylinder rocker shaft retaining stud provided that
a minimum wall thickness of more than half of the heli-coil diameter remains after
tapping for the heli-coil insert (reference Figure C-8).
5. If the hole is blind or if the hole goes through to a cavity subject to leakage, coat the
new stud’s course thread with High Strength Adhesive (Part No. 646941).
6. Drive the new stud with a tee handle stud driver. Turn it slowly and compare the
torque values listed in Appendix B.
7. Drive the stud in until it reaches the desired length specified stud height in the
primary ICA (reference Section 1-1.1).
C-6.2.1. Rosan® Stud Installation
Any type of Rosan ® stud (size-on-size type or step type) may be installed using the
appropriate wrench. Install the stud to the dimensions specified in Figure C-9.
CAUTION: Location of the flange is important in preventing the lock
ring drive tool from making contact with surface “A” in Figure C-9.
Any impact or pressure on surface A may damage the threads in the
cylinder head resulting in a loose fit.

Figure C-9. Rosan® Stud Installation Dimensions

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Maintenance Standards
C-7. Cotter Pin Installation
Cotter pins are not reusable. Replace used cotter pins with the specified new cotter pins
made of corrosion-resistant steel.
1. Install the nut on the bolt.
2. Torque the nut where the cotter pin is to be inserted to the lowest torque setting for
the fastener specified in Appendix B.
3. If the slots in the nut do not align with drilled hole in the bolt, gradually increase the
torque until the slot and hole align. Do not exceed the upper limit of the fastener
torque specification. Change the nut if necessary.
4. Insert the cotter pin through a hole with the head seated firmly in the slot of the nut.
5. Spread the exposed ends of the cotter pin. Bend the ends over the flat on the nut and
the end of the bolt.
CAUTION: Do not use side-cutting type pliers to bend back the
cotter pin ends. These pliers cause nicks which can weaken the cotter
pin to the extent that it can become detached.
6. Seat the ends firmly against the bolt and nut (Figure C-10).
WARNING
Wear eye protection when cutting cotter pin to avoid injury
from flying debris.
7. Trim the protruding ends as necessary.
8. All cotter pins must fit snugly in holes drilled in specific hardware. On castellated
nuts, unless otherwise specified, the cotter pin head must fit into a recess of the nut
with the other end bent such that one leg is back over the stud and the other is down
flat against the nut as shown in Figure C-10.

Figure C-10. Cotter Pin Installation

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 Maintenance Standards
C-8. Fuel System Service
CAUTION: Fuel system contamination may lead to component
damage, erratic engine operation, loss of power, or engine
shutdown. Flush new fuel system parts, hoses and test equipment
prior to connection to the system.
Fuel system service includes any inspection, service or repair action which requires
opening fuel system connections, including engine operational checks. Avoid introducing
contaminants into the fuel system:
• Exercise caution when installing fuel injection system parts.
• Clean surrounding component surfaces and fittings before removing parts or
disconnecting hoses or fittings.
• Cap or plug open fuel system hoses or fittings immediately upon disconnection. Caps
and plugs should remain in place until the time of reassembly.
• Use only clean tools and test equipment
• Purge fuel system components, regardless of source, at the time of installation.
C-8.1. Fuel System Purge
1. Remove the cap from the fuel inlet fitting of the fuel system component (hose,
pump, manifold valve, fuel control unit, in-line filter, or test equipment).
2. Connect the aircraft or engine fuel supply to the inlet fitting and tighten to prevent
leakage.
CAUTION: The receptacle used to collect the fuel sample must be
free of dust, debris, water, oil, or other particulates or contaminants
for valid inspection results.
3. Connect a clean section of fuel hose to the component fuel outlet(s) and direct the
end of the hose into a suitable, clean, one-half gallon (two liter) fuel receptacle.
4. Turn the fuel selector valve ON.
5. Turn the aircraft boost pump ON.
6. Allow at least one quart (.95L) of fuel to flow through the component into a clean
fuel receptacle. If the component features a mixture or throttle control lever, cycle
the lever through the full range of operation several times while fuel is flowing
through the component.
7. Turn the aircraft boost pump OFF and inspect the filter for contamination.
8. Allow at least two minutes for particulates to settle in the container. Visually inspect
the fuel in the container for contamination. If contamination is found, isolate and
correct the source of the contamination before proceeding with component
installation.
9. Repeat steps 4 through 8 until no contamination is found in the receptacle.
10. Proceed with component installation according to instructions in the primary ICA.

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Maintenance Standards

C-9. Gasket Maker® Application

Gasket Maker is an easily workable tacky gel which can be applied onto one side of a
flange surface from a tube and evenly spread.
WARNING
Apply Gasket Maker only as directed. The improper use of
sealants may cause engine malfunction or failure. Do not apply
any form of sealant to the crankcase cylinder deck, chamfer,
cylinder mounting flange, cylinder base O-ring, main bearing
bosses, or cylinder fastener threads. The use of RTV, silicone,
Gasket Maker or any other sealant on the areas listed above
during engine assembly will cause a loss of cylinder deck stud
or through-bolt torque. Subsequent loss of cylinder attachment
load, loss of main bearing crush and/or fretting of the
crankcase parting surfaces will occur. The result will be
cylinder separation, main bearing movement, oil starvation and
catastrophic engine failure. USE ONLY CLEAN 50 WEIGHT
AVIATION ENGINE OIL ON SURFACES LISTED.
1. Verify the surface where the sealant will be applied is clean and free of nicks, burrs,
oil, and grit.
2. For the engine nose seal, apply Part No. 653692 General Purpose Primer to prepare
the sealant surface before applying Gasket Maker at the engine nose seal area.
3. Apply and spread a thin, translucent coat of Part No. 646942 Gasket Maker (not to
exceed 0.010 inches in thickness) to the surface directly from the tube. For small
parts, use a polyester urethane sponge or a short nap roller saturated with Gasket
Maker to apply the sealant to the part.
4. Once Gasket Maker has been applied, evenly torque the assembly into place.
5. Wipe away excess sealant with chlorinated solvent.
6. To remove Gasket Maker from your hands, apply waterless mechanics hand soap
followed by soap and water.

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C-10. Gasket Installation
WARNING
Apply Gasket Maker only as directed. The improper use of
sealants may cause engine malfunction or failure. Do not apply
any form of sealant to the crankcase cylinder deck, chamfer,
cylinder mounting flange, cylinder base O-ring, main bearing
bosses, or cylinder fastener threads. The use of RTV, silicone,
Gasket Maker or any other sealant on the areas listed above
during engine assembly will cause a loss of cylinder deck stud
or through-bolt torque. Subsequent loss of cylinder attachment
load, loss of main bearing crush and/or fretting of the
crankcase parting surfaces will occur. The result will be
cylinder separation, main bearing movement, oil starvation and
catastrophic engine failure. USE ONLY CLEAN 50 WEIGHT
AVIATION ENGINE OIL ON SURFACES LISTED.
Gaskets and components must be properly positioned with the
hardware torqued and safety wired, as required, during
assembly to prevent oil loss.
Install only new gaskets. If the gasket material is age-sensitive (package or gasket is
stamped with a date code), verify the use by date has not passed. Inspect each gasket for
brittleness, cracks, wrinkles, damage, or deformities prior to installation. Do not use a
gasket with obvious defects, even if new; replace with a new manufacturer-specified
gasket. Verify that gasket surfaces are clean and free of nicks, burrs, oil, and grit.
CAUTION: Do not install brittle, dirty, cracked, or wrinkled gaskets.
Never reuse a gasket removed during disassembly.
1. Apply a thin coat of Part No. 642188 Gasket Sealant to both sides of the gasket
unless otherwise specified.
2. Install the gasket, following the contour of the mating surface.
3. Install the assembly and evenly torque the hardware to Appendix B specifications to
prevent damage to the gasket.
4. Safety wire the hardware where indicated.
C-10.1. Crush Washer Installation
Crush washers are commonly used at spark plug and oil sump plug bosses. The copper
material is soft and readily conforms to the two mating surfaces to form a tight seal.
1. Crush washers are one-time use items. Discard the crush washer during disassembly
and obtain a new crush washer for re-assembly.
2. If the crush washer exhibits a split line on one side, install the split line toward the
non-moving surface to avoid distortion. For example, at the oil sump, install the split
line against the oil sump boss rather than the plug.
3. Torque the fastener to the value specified in Appendix B; over-torquing risks
stripped threads.

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Maintenance Standards
C-11. Hose and Tubing Installation
Hoses and tubing to fuel, induction, lubrication, and turbocharger system fittings must be
properly installed.
WARNING
Failure to properly support component fittings can result in
fitting and/or component damage and a resulting loss of system
pressure or fluid.
1. Where multiple fittings are used, each fitting must be isolated from adjacent fittings
for proper torque application. Use a wrench on both mating connections to avoid
applying excessive torque to the fittings. Securely tighten fittings and torque to the
specified value in Appendix B. Torque the hose or tubing end fitting while
maintaining sufficient force on adjacent fittings to prevent twisting and shear loads.
CAUTION: Do not exceed specified torque values
2. Support the last fitting in the assembly on components that contain multiple fittings
coupled in one location. DO NOT over-torque fittings.

TORQUE WRENCH

TORQUE WRENCH
OPEN END/ FLARE
NUT WRENCH

OPEN END/ FLARE

NUT WRENCH

Figure C-11. Installing Hoses and Fittings

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 Maintenance Standards
C-12. Harness Routing
1. Inspect all proposed harness routes. Consider normal movement and relative motion
of the various engine or aircraft parts that will be attached to the harness.
2. Do not route harnesses near belts or pulleys without the use of belt guards; belt
failure may damage the wiring harness.
3. Do not secure wiring harnesses to fuel lines.
4. Use cushion clamps, with stand-off spacers, where necessary to secure the harness
to existing baffle supports and brackets where practical.
5. Secure harnesses to minimize the possibility of chafing, vibration, and excessive
heat exposure.
6. The largest allowable unsecured segment of wiring harnesses is eight (8) inches
(20.32 cm).
7. Route the wiring harnesses through baffles where necessary. All baffle penetrations
by a harness must be lined with a suitable grommet to prevent damage.

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Maintenance Standards

Intentionally Left Blank

C-26 Standard Practice Maintenance Manual

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