Lycoming YO-233-B2A User manual

© 2021 Avco Corporation. All Rights Reserved.
Engine Maintenance Manual
YO-233-B2A Engine
February 2021
Part No. MM-YO-233-B2A
(Supersedes Maintenance Manual LM-YO-233, dated June 2012)

YO-233-B2A Engine
Maintenance Manual
Lycoming Part Number: MM-YO-233-B2A
Contact Us:
Mailing Address:
Lycoming Engines
652 Oliver Street
Williamsport, PA 17701 USA
Phone:
Factory
U.S. and Canada Toll Free:
Direct:
[phone]
[phone]
Technical Support Hotline
•[phone] (Toll Free)
•[phone]
•Email [e-mail]
Lycoming’s regular business hours are Monday through Friday from 8:00AM through 5:00PM
Eastern Time (-5 GMT).
Visit us Online: www.lycoming.com
NOTE:
Lycoming recommends that owners of this manual sign up for email notification on the Technical
Publications page of our website https://www.lycoming.com/contact/knowledge-base/publications.
By submitting your email address, you will receive notification whenever Lycoming publishes a new
or revised service document.

TEO-540-A1A Engine Maintenance Manual
© 2021 Avco Corporation. All Rights Reserved Record of Revisions
February 2021 Page i
YO-233-B2A Engine Maintenance Manual
RECORD OF REVISIONS
Revision
Revision
Date
Revised By
Revision Description
Original
Original Release of Maintenance Manual –MM-YO-233-B2A
(Supersedes Maintenance Manual LM-YO-233, dated June 2012).
MM-YO-233-B2A has been formatted and incorporates changes
included in recently released and FAA approved maintenance
manuals. This manual contains the same basic information as LM-
YO-233 with significant changes to several chapters including 05-
00, 05-30, 05-50, 12-10, 72-30, and 74-30. This manual also
includes a description and instruction for an approved alternate
ignition system.

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© 2021 Avco Corporation. All Rights Reserved Service Document List
February 2021 Page iii
YO-233-B2A Engine Maintenance Manual
SERVICE DOCUMENT LIST
NOTICE: The following is a list of service documents referenced in or incorporated into the
information in this manual. Although the YO-233-B2A is not currently certified by the
FAA it is recommended that all inspections, procedures, and guidelines in the latest
revision of any service document (including any supplements) be followed to maintain
continued airworthiness.
Supplements to a service document contain information relevant to the service
document but not yet added to the service document.
The latest revision of all service documents in this list can be downloaded from our
website https://www.lycoming.com/contact/knowledge-base/publications.
To narrow the search parameters and limit the number of returns, enter only the
numerical portion of the service document number in the Search box on the website.
Number
Incorporation
Date
Subject
S.B. 369
02/21
Engine Inspection after Overspeed
S.B. 388
02/21
Procedure to Determine Exhaust Valve and Guide
Condition
S.B. 398
02/21
Recommended Corrective Action for Use of
Incorrect Fuel
S.B. 399
02/21
Action to Take If Loss of Oil Pressure
S.B. 401
02/21
Recommendations for Aircraft Struck by Lightning
S.B. 480
02/21
I. Oil Filter Change and Screen Cleaning
II. Oil Filter/Screen Content Inspection
S.B. 533
02/21
Recommendations Regarding Accidental Engine
Stoppage, Propeller/Rotor Strike or Loss of
Propeller/Rotor Blade Tip
S.I. 1014
02/21
Lubricating Oil Recommendations
S.I. 1042
02/21
Approved Spark Plugs
S.I. 1043
02/21
Spark Plug Heli-Coil Insert Replacement
S.I. 1080
02/21
Maintenance Items for Special Attention
S.I. 1191
02/21
Cylinder Compression
S.I. 1409
02/21
Lycoming Engines P/N LW-16702 Oil Additives
S.I. 1425
02/21
Suggested Maintenance Procedures to Reduce the
Possibility of Valve Sticking
S.I. 1462
02/21
Propeller Oil Control Leak Test Procedure
S.I. 1530
02/21
Engine Inspection in Particulate-Laden
Environments
S.I. 1566
02/21
Lycoming Engines Approves the Use of Safety
Cable

TEO-540-A1A Engine Maintenance Manual
Service Document List © 2021 Avco Corporation. All Rights Reserved
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YO-233-B2A Engine Maintenance Manual
SERVICE DOCUMENT LIST (CONT.)
Number
Incorporation
Date
Subject
S.L. L162
02/21
Heli-Coil®Service Repair Kit
S.L. L171
02/21
General Aspects of Spectrometric Oil Analysis
S.L. L192
02/21
Spark Plug Fouling
S.L. L197
02/21
Recommendations to Avoid Valve Sticking
S.L. L283
02/21
Alternate Ignition System

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February 2021 Page v
YO-233-B2A Engine Maintenance Manual
TABLE OF CONTENTS
Subject Page
Title Page _______________________________________________________________________
Record of Revisions.............................................................................................................................. i
Service Document List.......................................................................................................................iii
Table of Contents................................................................................................................................ v
Abbreviations and Acronyms ...........................................................................................................xi
Introduction......................................................................................................................................xiii
Required Maintenance ................................................................................................. 05-00
—General..................................................................................................................................... 1
—Tools for Maintenance............................................................................................................. 1
—Engine Overhaul vs. Engine Rebuild....................................................................................... 2
—Time Between Overhaul (TBO)............................................................................................... 2
—Safety Precautions - Before Engine Maintenance.................................................................... 2
—Maintenance Practices.............................................................................................................. 2
—General Engine Inspection Criteria.......................................................................................... 4
—Requirements for Engine Maintenance.................................................................................... 4
—Approved Parts......................................................................................................................... 4
—Corrosion Prevention............................................................................................................... 5
—Painting the Engine and Engine Components.......................................................................... 5
—Limits and Clearances.............................................................................................................. 7
—Inspections ............................................................................................................................... 7
Time Limits / Inspections............................................................................................. 05-10
—General..................................................................................................................................... 9
—Engine Inspection Schedule for YO-233-B2A Engines .......................................................... 9
Time Limits / Maintenance Checks-Scheduled Maintenance Checks ..................... 05-20
—Visual Inspection..................................................................................................................... 11
—10-Hour Initial Engine Inspection for YO-233-B2A Engines................................................ 14
—25-Hour Engine Inspection for YO-233-B2A Engines........................................................... 15
—50-Hour Engine Inspection for YO-233-B2A Engines........................................................... 18
—100-Hour or Annual Engine Inspection for YO-233-B2A Engines ....................................... 24
—400-Hour Engine Inspection for YO-233-B2A Engines......................................................... 29
—500-Hour Engine Inspection for YO-233-B2A Engines......................................................... 31
—1000-Hour Engine Inspection for YO-233-B2A Engines....................................................... 32

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Subject Page
Cleaning......................................................................................................................... 05-30
—Cleaning Guidelines................................................................................................................ 33
—Table 1 - Cleaning Guidelines for Engine Components .................................................... 34
—Grit-Blasting............................................................................................................................ 35
—Soft Carbon Removal.............................................................................................................. 36
—Hard Carbon Removal ............................................................................................................ 37
—Cylinder Cleaning................................................................................................................... 37
—Piston Cleaning....................................................................................................................... 38
—Steel, Aluminum, or Magnesium Parts Cleaning.................................................................... 39
—Spark Plug Cleaning................................................................................................................ 39
—Lead Deposit Removal............................................................................................................ 40
—Volcanic Ash Removal ........................................................................................................... 40
—Cleaning Guidelines for a Soaked Engine .............................................................................. 40
—Cleaning Methods for Non-Destructive Testing..................................................................... 41
Time Limits / Maintenance Checks –Unscheduled Maintenance............................ 05-50
—Lightning Strike - After a lightning strike .............................................................................. 43
—Engine Overspeed ................................................................................................................... 43
—Table 1 - Overspeed Values for YO-233-B2A Engines .................................................... 44
—Incorrect Fuel or Fuel Contamination..................................................................................... 45
—Soaked Engine......................................................................................................................... 46
—Engine on Fire or Near a Fire.................................................................................................. 47
—Hydraulic Lock ....................................................................................................................... 47
—Volcanic Ash/Particulate Contamination................................................................................ 47
—Table 2 - Action to Take in Volcanic Ash Conditions....................................................... 48
—Valve Sticking......................................................................................................................... 49
—Oil Starvation/Sudden Loss of Oil Pressure ........................................................................... 50
—Metal Contamination of the Lubrication System.................................................................... 51
—Propeller Strike, Sudden Engine Stoppage or Loss of a Propeller Blade TipCh_12_10........ 51
—Non-Destructive Testing
(Magnetic Particle Inspection and Fluorescent Penetrant Inspection.)................................... 58

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YO-233-B2A Engine Maintenance Manual
Subject Page
Servicing - Replenishing............................................................................................... 12-10
—Refueling................................................................................................................................. 59
—Oil Level Check...................................................................................................................... 59
—Oil Consumption..................................................................................................................... 60
—Oil Type and Viscosity ........................................................................................................... 60
—Add Oil to the Engine ............................................................................................................. 61
—Oil Leak Check ....................................................................................................................... 61
—Oil Servicing Schedule............................................................................................................ 61
—Oil Change Procedure............................................................................................................. 62
—Oil Filter Replacement............................................................................................................ 64
—Oil Suction Screen Removal/Installation................................................................................ 65
—Oil Filter/Oil Suction Screen Inspection................................................................................. 65
—Identification of Metallic Solids After Oil Servicing.............................................................. 65
—Visual Inspection of the Oil Filter Element and Oil Suction Screen...................................... 66
—Table 3 - Guidelines for Identification of Metal Particulates
and Chips & Corrective Action.......................................................................... 67
—Table 4 - Guidelines for Particle Quantity and Size on Oil Filter or Oil Suction Screen.. 69
—Recommended Corrective Action Options............................................................................. 71
—Table 5 - Recommended Corrective Action Options......................................................... 71
Fault Isolation................................................................................................................ 12-30
—General.................................................................................................................................... 73
—Fault Isolation Guide............................................................................................................... 73
—Table 1 - Fault Isolation Guide.......................................................................................... 73
Reciprocating Engine –Removal/Operational Ground Check ................................ 72-00
—Engine Removal Prerequisites................................................................................................ 87
—Engine Removal Procedure..................................................................................................... 87
—Engine Installation Preparation Requirements........................................................................ 89
—Engine Installation.................................................................................................................. 90
—Operational Ground Check After Maintenance...................................................................... 90
—Idle Speed Mixture Adjustment.............................................................................................. 90
—Engine Mount Inspection........................................................................................................ 91
—Return to Service Procedure ................................................................................................... 91

TEO-540-A1A Engine Maintenance Manual
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YO-233-B2A Engine Maintenance Manual
Subject Page
Reciprocating Engine –Crankcase ............................................................................. 72-20
—Crankcase System Description................................................................................................ 93
—Crankcase Maintenance .......................................................................................................... 93
—Crankcase Inspection Procedure............................................................................................. 93
Reciprocating Engine –Cylinder Inspections............................................................ 72-30
—General.................................................................................................................................... 95
—Table 1 - Regularly Scheduled Cylinder Inspections......................................................... 95
—Visual Cylinder Inspection...................................................................................................... 95
—Cylinder Compression Check ................................................................................................. 96
—Table 2 - Summary of Cylinder Compression Check Results and Corrective Action..... 100
—Intercylinder Baffle Inspection ............................................................................................. 101
—Cylinder Borescope Inspection............................................................................................. 102
—Table 3 - Borescope Inspection Steps, Results, and Corrective Action........................... 103
—Exhaust Valve and Guide Inspection.................................................................................... 103
—Cylinder Removal................................................................................................................. 109
—Piston Removal..................................................................................................................... 112
—Connecting Rod Removal..................................................................................................... 113
—Cylinder Assembly Inspection.............................................................................................. 114
—Piston Inspection................................................................................................................... 119
—Connecting Rod Inspection................................................................................................... 123
—Connecting Rod Bushing Replacement ................................................................................ 126
—Connecting Rod Parallelism/Squareness Check ................................................................... 128
—Connecting Rod Installation.................................................................................................. 129
—Piston Ring Replacement...................................................................................................... 131
—Piston Installation.................................................................................................................. 132
—Intake Valve Replacement .................................................................................................... 133
—Exhaust Valve Replacement ................................................................................................. 133
—Cylinder Installation.............................................................................................................. 134
—Corrective Action for Valve Sticking ................................................................................... 142
—Intake and Exhaust Valve Guide Replacement..................................................................... 143
—Intake and Exhaust Valve Seat Replacement........................................................................ 143
—Barrel Glaze and Varnish Removal from Interior Cylinder Barrel....................................... 144
—Heli-Coil®Replacement........................................................................................................ 144

TEO-540-A1A Engine Maintenance Manual
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February 2021 Page ix
YO-233-B2A Engine Maintenance Manual
Subject Page
Reciprocating Engine –Lubrication........................................................................... 72-50
—System Description............................................................................................................... 149
—Lubrication Maintenance ...................................................................................................... 149
Reciprocating Engine –Accessory Drives .................................................................. 72-60
—100-Hour Accessory Drive Inspection Procedure ................................................................ 151
Reciprocating Engine –Electrical System.................................................................. 72-70
—General.................................................................................................................................. 153
—100-Hour Wiring Inspection................................................................................................. 153
—Wiring Inspection.................................................................................................................. 153
—Alternator Belt Inspection..................................................................................................... 154
—Alternator Belt Tension Adjustment..................................................................................... 154
—Starter Ring Gear Support Replacement Procedure.............................................................. 154
Induction System........................................................................................................... 72-80
—System Description............................................................................................................... 155
—Induction System Inspection Procedure................................................................................ 155
Engine Fuel and Control - General............................................................................. 73-00
—System Description............................................................................................................... 157
Engine Fuel and Control - Distribution...................................................................... 73-10
—Fuel System Inspection Procedure........................................................................................ 159
—Fuel Filter Inspection Procedure........................................................................................... 159
Ignition System Maintenance....................................................................................... 74-00
—Ignition System Description.................................................................................................. 161
—Ignition System Maintenance................................................................................................ 161
—Table 1 - Ignition System Maintenance Items................................................................. 161
Ignition System –Spark Plug Maintenance ............................................................... 74-20
—Examine the Ignition Lead Routing...................................................................................... 163
—Remove the Spark Plug......................................................................................................... 163
—Examine Spark Plugs and Ignition Leads ............................................................................. 164
—Table 1 - General Spark Plug Wear/Replacement Guidelines......................................... 164
—Spark Plug Fouling................................................................................................................ 165
—Spark Plug Port Seal Inspection............................................................................................ 165

TEO-540-A1A Engine Maintenance Manual
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YO-233-B2A Engine Maintenance Manual
Subject Page
Ignition System –Spark Plug Maintenance (Cont.) .................................................. 74-20
—Clean the Spark Plugs........................................................................................................... 166
—Set Spark Plug Gap............................................................................................................... 166
—Spark Plug Rotation.............................................................................................................. 166
—Table 2 - Spark Plug Rotation Scheme............................................................................ 166
—Spark Plug Installation.......................................................................................................... 166
Electronic Ignition System ........................................................................................... 74-30
—Champion EIS Ignition System..........................................................................................169
—Remove the EIS ............................................................................................................... 169
—Install the EIS................................................................................................................... 169
—Light Speed Plasma III and Magneto Ignition System ....................................................169
—Convert the Engine from the Champion EIS Ignition System to the
Light Speed Plasma III and Magneto Ignition System.....................................................169
—Magneto Inspection.......................................................................................................... 170
—Magneto-to-Engine Timing Check .................................................................................. 170
—Magneto-to-Engine Timing Adjustment Procedure......................................................... 171
—Magneto Replacement Procedure .................................................................................... 172

TEO-540-A1A Engine Maintenance Manual
© 2021 Avco Corporation. All Rights Reserved Abbreviations and Acronyms
February 2021 Page xi
YO-233-B2A Engine Maintenance Manual
ABBREVIATIONS AND ACRONYMS
B
BHP
Brake Horsepower (per hour)
C
C
Celsius
F
F
Fahrenheit
FAA
Federal Aviation Administration
FAR
Federal Aviation (and Space) Regulation
FOD
Foreign Object Debris
ft.-lb
Foot Pound (torque)
H
hr
Hour
I
ID
Inside Diameter
in.-lb
Inch Pound (torque)
in.
Inch, inches
IOM
YO-233-B2A Engine Installation and Operation Manual
M
Max.
Maximum
MEK
Methyl-Ethyl-Ketone
O
OEM
Original Equipment Manufacturer
OHM
Direct Drive Overhaul Manual
P
psi
Pounds per square inch
Q
Qt
Quart
R
rpm
Revolutions per Minute
S
SAE
Society of Automotive Engineers
SB
Service Bulletin
SI
Service Instruction
SL
Service Letter

TEO-540-A1A Engine Maintenance Manual
Abbreviations and Acronyms © 2021 Avco Corporation. All Rights Reserved
Page xii February 2021
YO-233-B2A Engine Maintenance Manual
SMOH
Since Major Overhaul
STC
Supplemental Type Certificate
T
TBO
Time Between Overhaul
TDC
Top Dead Center
V
V
Volt, Voltage

TEO-540-A1A Engine Maintenance Manual
© 2021 Avco Corporation. All Rights Reserved Introduction
February 2021 Page xiii
YO-233-B2A Engine Maintenance Manual
INTRODUCTION
Engine Description
The Lycoming YO-233-B2A Series Engine (Figure 1) is an ASTM F2339 compliant direct drive,
four cylinder, carbureted, horizontally opposed, wet sump, air cooled engine. Refer to Figure 1.
Figure 1
YO-233-B2A Series Engine
Engine Model Nomenclature
This table shows the definition of each letter and number in the basic engine model number.
Model Number
Meaning
Y
Non-Certified
O
Horizontally Opposed
233
Displacement in cubic inches

TEO-540-A1A Engine Maintenance Manual
Introduction © 2021 Avco Corporation. All Rights Reserved
Page xiv February 2021
YO-233-B2A Engine Maintenance Manual
Engine Serial Number
Every engine sent from the factory is identified by a
unique serial number. The engine serial number is
identified on the engine data plate (Figure 2). Do not
remove the engine data plate.
If a data plate is ever lost or damaged, refer to the latest
revision of Service Instruction No. SI-1304 for data
plate replacement information.
Figure 2
Engine Data Plate
Cylinder Number Designations
•The propeller is at the front of the engine and the accessories are at the rear of the engine.
•In a top view of the engine, the left side cylinders are 2-4. Cylinder 2 is at the front of the
engine. Refer to Figure 3.
•In a top view of the engine, the left side cylinders are 1-3. Cylinder 1 is at the front of the
engine. Refer to Figure 3.
•The firing order of the cylinders is 1-3-2-4.
Figure 3
Top View of Engine –Cylinder Number Designations

TEO-540-A1A Engine Maintenance Manual
© 2021 Avco Corporation. All Rights Reserved Introduction
February 2021 Page xv
YO-233-B2A Engine Maintenance Manual
Scope of this Manual
Although the YO-233-B2A is not certified by the Federal Aviation Administration (FAA), this
manual adheres to guidelines set forth by the FAA for certified engines. It is recommended that all
inspections, procedures, and guidelines in this manual be followed to maintain continued
airworthiness.
This manual supplies instructions for service and maintenance of the Lycoming YO-233-B2A
engine. The information includes required maintenance (service information) for oil changes, oil
addition, oil filter replacement, routine time-interval inspections, routine service, spark plug
replacement/inspection procedures, cylinder inspection, fuel system inspection, scheduled servicing
procedures, fault isolation guidelines, and procedures for component replacement. Refer to the YO-
233-B2A Illustrated Parts Catalog to identify spare parts.
Engine Airworthiness
To operate and maintain this engine in safe and airworthy condition, operators and maintenance
personnel should have access to this manual, the latest revision of the Service Table of Limits - SSP-
1776, and all service documents applicable to this engine model.
WARNING: FOR CORRECT ENGINE MAINTENANCE, COMPLETE THE NECESSARY
MAINTENANCE PROCEDURES IN THIS MANUAL AND APPLICABLE
SERVICE DOCUMENTS. LYCOMING ENGINES' SERVICE DOCUMENTS
WRITTEN AT A LATER DATE OVERRIDE PROCEDURES IN THIS
MANUAL UNLESS OTHERWISE SPECIFIED.
PROCEDURES IN THIS MANUAL MUST BE DONE BY QUALIFIED
PERSONNEL WITH THE REQUISITE CERTIFICATIONS.
Before you do maintenance on the YO-233-B2A engine, read this manual in its entirety. Obey all
procedures and inspections in this manual.
NOTICE: If you do not obey the maintenance procedures in this manual for this engine, you can
void the engine warranty. Please consult your warranty for a full a statement of your
rights, limitations and obligations that exist there under.
Refer to the YO-233-B2A Engine Installation and Operation Manual for engine description,
uncrating procedures, acceptance check, engine lift procedure, engine preservation and storage,
depreservation, engine installation requirements, engine installation, engine start, operation, and stop
procedures, engine initiation, fuels and oil to be used, and operating specifications.
Refer to the latest revision of the Service Table of Limits - SSP-1776, for dimensions, clearances,
measurements, and torque values.
WARNING: OPERATE THIS ENGINE IN ACCORDANCE WITH SPECIFICATIONS IN
APPENDIX A OF THE YO-233-B2A ENGINE INSTALLATION AND
OPERATION MANUAL. OPERATION OF THE ENGINE OUTSIDE OF THE
SPECIFIED OPERATING LIMITS CAN CAUSE PERSONAL INJURY
AND/OR DAMAGE TO THE ENGINE.
Environmental Compliance
Lycoming Engines recommends that engine owners and engine service personnel be in compliance
with all federal, state, and local environmental regulations when solvents, paint, fuel, oil, chemicals,
or other consumables are used in engine service.

TEO-540-A1A Engine Maintenance Manual
Introduction © 2021 Avco Corporation. All Rights Reserved
Page xvi February 2021
YO-233-B2A Engine Maintenance Manual
Warnings, Cautions, and Notices
Be sure to read and obey the Warnings, Cautions, and Notices in this manual and in service
documents. Although Lycoming Engines cannot know all possible hazards or damages, it makes a
reasonable effort to supply the best known guidance and recommended practices for safe operation
and maintenance of its engines.
The table below defines the four types of safety advisory messages used in this manual as per the
American National Standard and ANSI Z535-6-2006.
Safety Advisory Conventions
Advisory Word
Definition
DANGER:
Indicates a hazardous situation which, if not avoided, will result
in death or serious injury. This signal word is to be limited to the
most extreme situations.
WARNING:
Indicates a hazardous situation which, if not avoided, could
result in death or serious injury.
CAUTION:
Indicates a hazardous situation which, if not avoided, could
result in minor or moderate injury. It also can be used without
the safety alert symbol as an alternative to "NOTICE."
NOTICE:
The preferred signal word to address practices not related to
personal injury.
NOTICE: In this manual, the word "recommend" refers to "best practices."
Service Bulletins, Service Instructions, and Service Letters
As advancements in technological applications on this engine continue, Lycoming will make future
revisions to this manual. However, if more timely distribution is necessary, Lycoming supplies up-
to-date Service Bulletins (SBs), Service Instructions (SIs) and Service Letters (which are abbreviated
with a capital “L” followed by the number, example L180). Special Advisories (SAs) are supplied as
necessary.
For additional publication information, look on Lycoming’s website (Lycoming.com) or speak to
Lycoming Engines by telephone: U.S. and Canada toll free: [phone]; or Direct: +1 (570)
323-6181.
Applicable information from Lycoming Engines' Service Bulletins, Service Instructions, and Service
Letters are included in this manual at the time of publication. Any new service information will be
included in the next update of the manual.
Reminder: Unless otherwise specified, Lycoming Engines' service documents (which are dated
after this manual’s release date) override procedures in this manual.
For reference, the Service Document List at the front of this manual shows the service documents
referenced or included in this manual.
List of Publications
Refer to the latest revision of Service Letter No. L114 for a list of Lycoming Engines' publications.

TEO-540-A1A Engine Maintenance Manual
© 2021 Avco Corporation. All Rights Reserved Introduction
February 2021 Page xvii
YO-233-B2A Engine Maintenance Manual
Instructions for Continued Airworthiness
This manual, together with the Installation and Operation Manual, Overhaul Manual, Service
Documents and related publications make up the complete set of Instructions for Continued
Airworthiness (ICAs).
Simplified Technical English
The text in the manual is written in the form of Simplified Technical English to make translation into
other languages easier.
Format
Chapters in this manual are identified in Air Transport Association (ATA) format.
Figures
Figures in this manual are for illustration purposes only. Figures always start as Figure 1 in each
chapter.
Table and Checklists
Tables in this manual are used to display detailed information in an organized format. Tables always
start as Table 1 in each chapter. Checklists are used to display a list of tasks to be completed as part
of a specific procedure. Checklists are not numbered because they are used as a reference tool
contained within the procedure.
Copyright
This publication is a copyrighted work. All rights reserved by Lycoming Engines. Content in this
manual cannot be changed or released as a reprint, electronic media output, or web communiqué
without written permission from Lycoming Engines.
Feedback
To supply comments, suggestions, or corrections to this manual, either email or contact Lycoming
Engines Technical Support at the email or phone number in the front of this manual or use the
Lycoming.com website.
Manual Revisions
Lycoming Engines constantly examines our manuals to provide our customers the most complete
and up-to-date information for operating and maintaining our engines. Revisions to this manual will
be published as necessary.

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