Lycoming IO-390-D Series User manual

© 2020 Avco Corporation. All Rights Reserved.
Engine Maintenance Manual
(Principal Manual)
IO-390-D Series
March 2020
Part No. MM-IO-390-D Series

IO-390-D Series
Engine Maintenance Manual
Lycoming Part Number: MM-IO-390-D Series
Contact Us:
Mailing Address:
Lycoming Engines
652 Oliver Street
Williamsport, PA 17701 USA
Phone:
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IO-390-D Series Engine Maintenance Manual
© 2020 Avco Corporation. All Rights Reserved Airworthiness Limitations
March 2020 Page i
IO-390-D Series Engine Maintenance Manual
AIRWORTHINESS LIMITATIONS
1. General
This Airworthiness Limitations chapter sets forth each mandatory replacement time,
inspection interval, and related procedure required for type certification. The
Airworthiness Limitations chapter is FAA approved and specifies maintenance required
under §§ 43.16 and 91.403 of the Federal Aviation Regulations (FAR) unless an
alternative program has been FAA-approved.
2. Mandatory Inspection - Fuel Injector Lines
At every 100 hours of operation and after any maintenance has been done on the engine
where the fuel injector lines have been disconnected, moved or loosened, examine the
fuel lines per the "Fuel Line Inspection" procedure in Chapter 73-10 of this manual.
3. Mandatory Inspection - Exhaust Valve and Guide
At every 1000 hours of operation for IO-390-D Series engines, examine the exhaust valve
and guide conditions. Refer to the section "Exhaust Valve and Guide Inspection" in
Chapter 72-30.

IO-390-D Series Engine Maintenance Manual
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IO-390-D Series Engine Maintenance Manual
© 2020 Avco Corporation. All Rights Reserved Record of Revisions
March 2020 Page iii
IO-390-D Series Engine Maintenance Manual
RECORD OF REVISIONS
Revision
Revision
Date
Revised
By
Revision Description
Original
Original Release of Maintenance Manual –
Part No. MM-IO-390-D Series

IO-390-D Series Engine Maintenance Manual
Record of Revisions © 2020 Avco Corporation. All Rights Reserved
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IO-390-D Series Engine Maintenance Manual
© 2020 Avco Corporation. All Rights Reserved Service Document List
March 2020 Page v
IO-390-D Series 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. Always refer to the latest revision of any service document
(including any supplements) for changes or additional information. 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. 201
03/20
Inspection of Crankshaft Flange
S.B. 225
03/20
Replacement of Valve Rocker Thrust Washers
S.B. 240
03/20
Mandatory Parts Replacement at Overhaul and
During Repair or Maintenance
S.B. 342
03/20
Fuel Line (Stainless Steel Tube Assy.) and Support
Clamp Inspection and Installation
S.B. 357
03/20
Engine Inspection After an Engine Has Been Soaked
or Immersed
S.B. 369
03/20
Engine Inspection after Overspeed
S. B. 388
03/20
Procedure to Determine Exhaust Valve and Guide
Condition
S.B. 398
03/20
Recommended Corrective Action for Use of
Incorrect Fuel
S.B. 399
03/20
Action to Take If Loss of Oil Pressure
S.B. 401
03/20
Recommendations for Aircraft Struck by Lightning
S.B. 475
03/20
Crankshaft Gear and Crankshaft Gear End Inspection
and Corrective Action
S.B. 480
03/20
Oil, Oil Filter, Oil Pressure Screen, and Oil Suction
Screen Servicing
S.B. 505
03/20
Inspection of Crankshaft I.D. for Corrosion
S.B. 533
03/20
Recommended Action for Sudden Engine Stoppage,
Propeller/Rotor Strike or Loss of Propeller/Rotor
Blade or Tip
S.I. 1009
03/20
Recommended Time Between Overhaul Periods
S.I. 1011
03/20
Tappets and Lifters
S.I. 1012,
Supplement 1,
Supplement 2
03/20
Counterweights and Rollers on Engine Models

IO-390-D Series Engine Maintenance Manual
Service Document List © 2020 Avco Corporation. All Rights Reserved
Page vi March 2020
IO-390-D Series Engine Maintenance Manual
SERVICE DOCUMENT LIST (CONT.)
Number
Incorporation
Date
Subject
S.I. 1014
03/20
Lubricating Oil Recommendations
S.I. 1029
03/20
Tightening Procedures for Crankcase Thru-Studs and
Bolts
S.I. 1037
03/20
Approved Pistons, Rings and Cylinders for Use on
Lycoming Aircraft Engines
S.I. 1042
03/20
Approved Spark Plugs
S.I. 1043
03/20
Spark Plug Heli-Coil®Insert Replacement
S.I. 1047
03/20
Inspection and Reconditioning Procedures for Nitride
Hardened Steel Cylinders
S.I. 1059
03/20
Pre-Lubrication of Parts Before Assembly
S.I. 1060
03/20
Push Rod Identification
S.I. 1070
03/20
Specified Fuels for Spark Ignited Gasoline Aircraft
Engine Models
S.I. 1080
03/20
Maintenance Items for Special Attention
S.I. 1098
03/20
Propeller Flange Bushing Location
S.I. 1129
03/20
Methods of Checking DC Alternator and Generator
Belt Tension
S.I. 1141
03/20
Replacement of Worn Starter Ring Gears
S.I. 1143
03/20
Counterweight Bushing Inspection, Replacement,
and Special Tooling Upgrades
S.I. 1154
03/20
FAA-Approved Starters and Alternators
S.I. 1172
03/20
Adjustable Oil Pressure Relief Valve Installation and
Valve Seat Repair or Replacement
S.I. 1191
03/20
Cylinder Compression Check
S.I. 1241
03/20
Pre-oil the Engine Prior to Initial Start
S.I. 1267
03/20
Piston Pin Plug Usage
S.I. 1285
03/20
Non-Destructive Testing of Lycoming Engine Parts
S.I. 1290
03/20
Repair of Oil Leakage at Crankcase Thru-Stud
Locations; Assembled and Unassembled Engines.
S.I. 1301
03/20
Identification of Primer and Fuel Injector Lines
S.I. 1304
03/20
Engine Nameplate Replacement
S.I. 1316
03/20
Valve Seat Refacing on Oil Cooler Bypass Valves
S.I. 1324
03/20
Crankshaft Oil Seals
S.I. 1340
03/20
Piston Pin Identification
S.I. 1343
03/20
Set Screw for Propeller Governor Idler Shaft

IO-390-D Series Engine Maintenance Manual
© 2020 Avco Corporation. All Rights Reserved Service Document List
March 2020 Page vii
IO-390-D Series Engine Maintenance Manual
SERVICE DOCUMENT LIST (CONT.)
S.I. 1409
03/20
Lycoming Engines P/N LW-16702 Oil Additives
S.I. 1425
03/20
Suggested Maintenance Procedures to Reduce the
Possibility of Valve Sticking
S.I. 1427
03/20
Field Run-In and Break-In
S.I. 1458
03/20
Connecting Rod Bolts (Identification and
Installation)
S.I. 1462
03/20
Propeller Oil Control Leak Test Procedure
S.I. 1485
03/20
Exhaust Valve and Guide Identification Procedure
S.I. 1492
03/20
Piston Pin Plug Wear Inspection
S.I. 1514
03/20
Roller Tappets Part Information Update
S.I. 1529
03/20
Hydraulic Lifter and Tappet Body Part Numbers
S.I. 1530
03/20
Engine Inspection in Particulate-Laden Environments
S.I. 1535
03/20
Counterweight and Roller Removal, Inspection, and
Installation
S.I. 1566
03/20
Lycoming Engines Approves the Use of Safety Cable
S.I. 1569
03/20
Installation of Lycoming Electronic Ignition System
(EIS)
S.I. 1575
03/20
New Connecting Rod Bushing
S.L. L114
03/20
Reciprocating Engine and Accessory Maintenance
Publications
S.L. L171
03/20
General Aspects of Spectrometric Oil Analysis
S.L. L180
03/20
Engine Preservation Guidelines for Active and Stored
Aircraft
S.L. L192
03/20
Spark Plug Fouling
S.L. L197
03/20
Recommendations to Avoid Valve Sticking
S.L. L221
03/20
Warranty Repair of Precision Airmotive Corporation
Fuel Control Products
S.L. L247
03/20
Shelf Life Requirements
S.L. L253
03/20
Warranty Repair of AVStar Fuel Systems, Inc. Fuel
Control Products
S.L. L272
03/20
Release of New Silicone Rocker Cover Gaskets

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