Textron LYCOMING O-320 Series Operator's Manual
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Textron LYCOMING O-320 Series Operator's Manual

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Operator's Manual
Lycoming
O-320 Series
Approved by FAA
3rd Edition
Part No. 60297-30
October 2006
652 Oliver Street
Williamsport, PA. 17701 U.S.A.
570/323-6181

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  • Page 1 Operator’s Manual Lycoming O-320 Series Approved by FAA 3rd Edition Part No. 60297-30 October 2006 652 Oliver Street Williamsport, PA. 17701 U.S.A. 570/323-6181...
  • Page 2 652 Oliver Street Williamsport, PA 17701 U.S.A. Phone: Factory: 570-323-6181 Sales Department: 570-327-7268 Fax: 570-327-7101 Lycoming’s regular business hours are Monday through Friday from 8:00 AM through 5:00 PM Eastern Time (-5 GMT) Visit us on the World Wide Web at: http://www.lycoming.textron.com...
  • Page 3 LYCOMING OPERATOR’S MANUAL ATTENTION OWNERS, OPERATORS, AND MAINTENANCE PERSONNEL This operator’s manual contains a description of the engine, its specifications, and detailed information on how to operate and maintain it. Such maintenance procedures that may be required in conjunction with periodic inspections are also included.
  • Page 4 LYCOMING OPERATOR’S MANUAL IMPORTANT SAFETY NOTICE Proper service and repair is essential to increase the safe, reliable operation of all aircraft engines. The service procedures recommended by Lycoming are effective methods for performing service operations. Some of these operations require the use of tools specially designed for the task. These special tools must be used when and as recommended.
  • Page 5 WARRANTY NEW AND REBUILT ENGINES (1) WARRANTY AND REMEDY: Lycoming Engines, a division of Avco Corporation (hereinafter “Lycoming”) warrants each new Lycoming reciprocating engine to be free from defect in material or workmanship under normal use and service. Lycoming’s sole obligation under this warranty is limited to replacement or repair of parts which are determined by Lycoming to have been defective within a period of twenty-four (24) months after new aircraft delivery to the original retail purchaser or first user, or twenty-four (24) months from the date of first operation.
  • Page 6 (7) Any invalidity of a provision of this Warranty shall not affect any other provision, and in the event of a judicial finding of such invalidity, this Agreement shall remain in force in all other respects. Effective September 2006 Revision “M” Lycoming Engines 652 Oliver Street Williamsport, Pennsylvania 17701 (570) 323-6181 www.lycoming.textron.com...

  • Page 7: Table Of Contents

    LYCOMING OPERATOR’S MANUAL TABLE OF CONTENTS Page SECTION 1 DESCRIPTION SECTION 2 SPECIFICATIONS SECTION 3 OPERATING INSTRUCTIONS SECTION 4 PERIODIC INSPECTIONS SECTION 5 MAINTENANCE PROCEDURES SECTION 6 TROUBLE-SHOOTING SECTION 7 INSTALLATION AND STORAGE SECTION 8 TABLES...
  • Page 8 LYCOMING OPERATOR’S MANUAL ¾ Right Front View – Typical O-320 Series ¾ Left Rear View – Typical O-320 Series...

  • Page 9: Description

    LYCOMING OPERATOR’S MANUAL SECTION 1 DESCRIPTION Page General................................1-1 Cylinders............................... 1-1 Valve Operating Mechanism ........................1-1 Crankcase ..............................1-1 Crankshaft ..............................1-1 Connecting Rods ............................1-1 Pistons ................................1-1 Accessory Housing ............................1-1 Oil Sump ............................... 1-1 Cooling System ............................. 1-2 Induction System............................
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  • Page 11 LYCOMING OPERATOR’S MANUAL SECTION 1 O-320 SERIES DESCRIPTION SECTION 1 DESCRIPTION The O-320 series are four cylinder, direct drive and, horizontally opposed, air cooled engines. In referring to the location of the various engine components, the parts are described in their relationship to the engine as installed in the airframe.
  • Page 12 Induction System - Lycoming O-320 series engines are equipped with a float type carburetor. Particularly good distribution of the fuel-air mixture to each cylinder is obtained through the center zone induction system, which is integral with the oil sump and is submerged in oil, insuring a more uniform vaporization of fuel and aiding in cooling the oil in the sump.
  • Page 13 LYCOMING OPERATOR’S MANUAL SECTION 1 O-320 SERIES DESCRIPTION TABLE 1 MODEL APPLICATION Model Left Right Height Width Length O-320 -A1A, -A1B S4LN-21 S4LN-20 22.99 32.24 29.56 -A2A*, -A2B* S4LN-21 S4LN-20 22.99 32.24 29.56 -A3A, -A3B S4LN-21 S4LN-20 22.99 32.24 29.56 -A2C*, -A3C S4LN-200 S4LN-204...
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  • Page 15: Specifications

    LYCOMING OPERATOR’S MANUAL SECTION 2 SPECIFICATIONS Page Explanatory Note ............................2-1 Specifications – O-320-A, -B, -D, -E Series....................2-2 Accessory Drive Ratio..........................2-3 Detail Weights .............................. 2-3...
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  • Page 17 LYCOMING OPERATOR’S MANUAL SECTION 2 O-320 SERIES SPECIFICATIONS SECTION 2 SPECIFICATIONS The model specifications shown on the following pages of this section are divided according to model designation. When differences among models can be clearly stated, the specifications of more than one model are combined in a single group;...
  • Page 18 SECTION 2 LYCOMING OPERATOR’S MANUAL SPECIFICATIONS O-320 SERIES SPECIFICATIONS O-320-A, -E* SERIES FAA Type Certificate ............................274 Rated horsepower............................150 Rated speed, RPM............................2700 Bore, inches..............................5.125 Stroke, inches..............................3.875 Displacement, cubic inches.........................319.8 Compression ratio ............................7.0:1 Firing order ............................. 1-3-2-4 Spark occurs, degrees BTC..........................25 Valve rocker clearance (hydraulic tappets collapsed) .................
  • Page 19 LYCOMING OPERATOR’S MANUAL SECTION 2 O-320 SERIES SPECIFICATIONS *Accessory Drive Drive Ratio **Direction of Rotation Starter 13.556:1 Counterclockwise Starter 16.556:1 Counterclockwise Generator 1.910:1 Clockwise Generator 2.500:1 Clockwise Alternator 3.250:1 Clockwise Tachometer 0.500:1 Clockwise Magneto 1.000:1 Clockwise Vacuum Pump 1.300:1 Counterclockwise Propeller Governor AN20010 Mounted on Accessory Housing 0.866:1...
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  • Page 21: Operating Instructions

    LYCOMING OPERATOR’S MANUAL SECTION 3 OPERATING INSTRUCTIONS Page General................................3-1 Prestarting Items of Maintenance ......................3-1 Starting Procedures ............................. 3-1 Cold Weather Starting ..........................3-2 Ground Running and Warm-Up ........................ 3-2 Ground Check .............................. 3-3 Operation in Flight ............................3-4 Fuel Mixture Leaning Procedures......................
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  • Page 23: Prestarting Items Of Maintenance

    LYCOMING OPERATOR’S MANUAL SECTION 3 O-320 SERIES OPERATING INSTRUCTIONS SECTION 3 OPERATING INSTRUCTIONS 1. GENERAL. Close adherence to these instructions will greatly contribute to long life, economy and satisfactory operation of the engine. NOTE YOUR ATTENTION IS DIRECTED TO THE WARRANTIES THAT APPEAR IN THE FRONT OF THIS MANUAL REGARDING ENGINE SPEED, THE USE OF SPECIFIED FUELS AND LUBRICANTS, REPAIRS AND ALTERATIONS.

  • Page 24: Cold Weather Starting

    SECTION 3 LYCOMING OPERATOR’S MANUAL OPERATING INSTRUCTIONS O-320 SERIES a. Cold Engines. (1) Perform pre-flight inspection. (2) Set carburetor heat control in “off” position. (3) Set propeller governor control in “Full RPM” position (where applicable). (4) Turn fuel valves “On”. (5) Move mixture control to “Full Rich”.

  • Page 25: Ground Check

    LYCOMING OPERATOR’S MANUAL SECTION 3 O-320 SERIES OPERATING INSTRUCTIONS a. Head the aircraft into the wind. b. Leave mixture in “Full Rich”. c. Operate only with the propeller in minimum blade angle setting. d. Warm-up at approximately 1000-1200 RPM. Avoid prolonged idling and do not exceed 2200 RPM on the ground.

  • Page 26: Operation In Flight

    SECTION 3 LYCOMING OPERATOR’S MANUAL OPERATING INSTRUCTIONS O-320 SERIES 7. OPERATION IN FLIGHT a. See airframe manufacturer’s instructions for recommended power settings. b. Fuel Mixture Leaning Procedure. Improper fuel/air mixture during flight is responsible for many engine problems, particularly during take-off and climb power settings.

  • Page 27: With Manual Mixture Control

    LYCOMING OPERATOR’S MANUAL SECTION 3 O-320 SERIES OPERATING INSTRUCTIONS (2) Best Economy Cruise (approximately 75% power and below) – Operate at peak EGT, or if desired, drop 50°F on rich side of peak EGT. 2. LEANING TO FLOWMETER. Lean to applicable fuel-flow tables or lean to indicator marked for correct fuel-flow for each power setting.

  • Page 28: Engine Flight Chart

    SECTION 3 LYCOMING OPERATOR’S MANUAL OPERATING INSTRUCTIONS O-320 SERIES (2) Take-Off – Take-offs and full throttle operation should be made with carburetor heat in full cold position. The possibility of throttle icing at wide throttle openings is very remote, so remote in fact, that it can be disregarded.

  • Page 29: Operating Conditions

    LYCOMING OPERATOR’S MANUAL SECTION 3 O-320 SERIES OPERATING INSTRUCTIONS FUEL AND OIL (CONT.) ALL MODELS *Recommended Grade Oil Average MIL-L-6082 Ashless Dispersant Ambient Air Grades Grades Above 80°F SAE 60 SAE 60 Above 60°F SAE 50 SAE 40 or SAE 50 30°F to 90°F SAE 40 SAE 40...

  • Page 30: Engine Shut Down

    SECTION 3 LYCOMING OPERATOR’S MANUAL OPERATING CONDITIONS O-320 SERIES OPERATING CONDITIONS (CONT) Fuel Max. *Max. Cons. Oil Cons. Cyl. Head Operation Gal./Hr. Qts./Hr. Temp. O-320-A, -E** Series Normal Rated 2700 ------ 500°F (260°C) Performance Cruise (75% Rated) 2450 10.0 500°F (260°C) Economy Cruise (65% Rated) 2350...
  • Page 31 LYCOMING OPERATOR’S MANUAL SECTION 3 O-320 SERIES OPERATING CONDITIONS Figure 3-1. Representative Effect of Leaning on Cylinder Head Temperature, EGT (Exhaust Gas Temperature), Engine Power and Specific Fuel Consumption at Constant Engine RPM and Manifold Pressure...
  • Page 32 SECTION 3 LYCOMING OPERATOR’S MANUAL OPERATING INSTRUCTIONS O-320 SERIES Figure 3-2. Sea Level Power Curve – O-320-A and –E Series 3-10...
  • Page 34 SECTION 3 LYCOMING OPERATOR’S MANUAL OPERATING INSTRUCTIONS O-320 SERIES Figure 3-4. Part Throttle Fuel Consumption – O-320-A and –E Series 3-12...
  • Page 35 LYCOMING OPERATOR’S MANUAL SECTION 3 O-320 SERIES OPERATING INSTRUCTIONS Figure 3-5. Sea Level Power Curve – O-320-B and –D Series (Except O-320-B2D) 3-13...
  • Page 36 SECTION 3 LYCOMING OPERATOR’S MANUAL OPERATING INSTRUCTIONS O-320 SERIES Figure 3-6. Sea Level Power Curve – O-320-B2D 3-14...
  • Page 40 SECTION 3 LYCOMING OPERATOR’S MANUAL OPERATING INSTRUCTIONS O-320 SERIES Figure 3-10. Fuel Flow vs. Percent Rated Power – O-320-B2E 3-18...

  • Page 41: Periodic Inspections

    LYCOMING OPERATOR’S MANUAL SECTION 4 PERIODIC INSPECTION Page General................................4-1 Pre-Starting Inspection ..........................4-1 Daily Pre-Flight............................4-2 25-Hour Inspection ............................4-2 50-Hour Inspection ............................4-2 100-Hour Inspection ............................ 4-3 400-Hour Inspection ............................ 4-4 Non-Scheduled Inspection........................... 4-4...
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  • Page 43 LYCOMING OPERATOR’S MANUAL SECTION 4 O-320 SERIES PERIODIC INSPECTION SECTION 4 PERIODIC INSPECTION NOTE Perhaps no other factor is quite so important to safety and durability of the aircraft and its components as faithful and diligent attention to regular checks for minor troubles and prompt repair when they are found.
  • Page 44 SECTION 4 LYCOMING OPERATOR’S MANUAL PERIODIC INSPECTION O-320 SERIES 1. DAILY PRE-FLIGHT. a. Be sure all switches are in the “Off” position. b. Be sure magneto ground wires are connected. c. Check oil level. d. Be sure that fuel tanks are full. e.
  • Page 45 LYCOMING OPERATOR’S MANUAL SECTION 4 O-320 SERIES PERIODIC INSPECTION (3) Check ignition harness for security of mounting clamps and be sure connections are tight at spark plug and magneto terminals. b. Fuel and Induction System – Check the primer lines (where applicable) for leaks and security of the clamps.
  • Page 46 SECTION 4 LYCOMING OPERATOR’S MANUAL PERIODIC INSPECTION O-320 SERIES (2) Remove spark plugs; test, clean and regap. Replace if necessary. b. Magnetos – Check breaker points for pitting and minimum gap. Check for excessive oil in the breaker compartment, if found, wipe dry with a clean lint free cloth. The felt located at the breaker points should be lubricated in accordance with the magneto manufacturer’s instructions.

  • Page 47: Maintenance Procedures

    LYCOMING OPERATOR’S MANUAL SECTION 5 MAINTENANCE PROCEDURES Page General................................5-1 Ignition and Electrical System Ignition Harness and Wire Replacement....................5-1 Timing Magneto to Engine Single Magneto ............................5-1 Fuel System Repair of Fuel Leaks..........................5-3 Carburetor Fuel Inlet Screen Assembly ....................5-3 Fuel Grade and Limitations........................
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  • Page 49 LYCOMING OPERATOR’S MANUAL SECTION 5 O-320 SERIES MAINTENANCE PROCEDURES SECTION 5 MAINTENANCE PROCEDURES The procedures described in this section are provided to guide and instruct personnel in performing such maintenance operations that may be required in conjunction with the periodic inspections listed in the preceding section.
  • Page 50 SECTION 5 LYCOMING OPERATOR’S MANUAL MAINTENANCE PROCEDURES O-320 SERIES FIRING ORDER MAGNETO – Left Hand Rotation – 1-3-2-4 MAGNETO – Right Hand Rotation – 1-4-2-3 Figure 5-1. Ignition Wiring Diagram...
  • Page 51 LYCOMING OPERATOR’S MANUAL SECTION 5 O-320 SERIES MAINTENANCE PROCEDURES FIRING ORDER MAGNETO – Left Hand Rotation – 1-3-2-4 MAGNETO – Right Hand Rotation – 1-4-2-3 Figure 5-2. Ignition Wiring Diagram (Optional)
  • Page 52 SECTION 5 LYCOMING OPERATOR’S MANUAL MAINTENANCE PROCEDURES O-320 SERIES (Impulse Coupling Magneto) – Hold the T1 or B1 lead wire spring 1/16 in. to 1/8 in. away from the magneto frame and turn the impulse coupling one click at a time until a strong spark jumps between the spring and the frame.
  • Page 53 LYCOMING OPERATOR’S MANUAL SECTION 5 O-320 SERIES MAINTENANCE PROCEDURES c. Fuel Grades and Limitations – The recommended aviation grade fuel for the subject engines is listed in Section 3, Item 9. In the event that the specified fuel is not available at some locations, it is permissible to use higher octane fuel.
  • Page 54 SECTION 5 LYCOMING OPERATOR’S MANUAL MAINTENANCE PROCEDURES O-320 SERIES NOTE On installations employing full flow oil filters, this step is not practical at this time, but should be observed at the 50-hour inspection, not to exceed four (4) months between oil changes.
  • Page 55 LYCOMING OPERATOR’S MANUAL SECTION 5 O-320 SERIES MAINTENANCE PROCEDURES NOTE The hydraulic tappets, push rods, rocker arms and valves must be assembled in the same location from which they were removed. (7) Remove cylinder base nuts and hold down plates (where employed) then remove cylinder by pulling directly away from crankcase.
  • Page 56 SECTION 5 LYCOMING OPERATOR’S MANUAL MAINTENANCE PROCEDURES O-320 SERIES NOTE When installing valve springs, place the dampener end of spring (close wound coils marked with dye or lacquer) toward the cylinder. Using a valve spring compressor, compress the valve springs and place the split keys in the groove around the upper end of the valve stem.
  • Page 57 LYCOMING OPERATOR’S MANUAL SECTION 5 O-320 SERIES MAINTENANCE PROCEDURES Figure 5-3. Location of Shims Between Cylinder Barrel and Hold-Down Plates (where applicable) and Sequence of Tightening Cylinder Base Hold-Down Nuts (c) Tighten the ⅜ inch hold-down nuts to 300 in.-lbs. (25 ft.-lbs.) torque. Sequence of tightening is optional.
  • Page 58 SECTION 5 LYCOMING OPERATOR’S MANUAL MAINTENANCE PROCEDURES O-320 SERIES (6) Install a new shroud tube oil seal on the crankcase end of each shroud tube and fit a new annular ring in the groove provided in the rocker box and of each shroud tube. Install each shroud tube through rocker box and seat the end firmly in the crankcase.

  • Page 59: Trouble-Shooting

    LYCOMING OPERATOR’S MANUAL SECTION 6 TROUBLE-SHOOTING Page Failure of Engine to Start..........................6-1 Failure of Engine to Idle Properly......................6-2 Low Power and Uneven Running....................... 6-2 Failure of Engine to Develop Full Power....................6-3 Rough Engine ............................... 6-3 Low Oil Pressure............................6-3 High Oil Temperature ..........................
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  • Page 61: Failure Of Engine To Start

    LYCOMING OPERATOR’S MANUAL SECTION 6 O-320 SERIES TROUBLE-SHOOTING SECTION 6 TROUBLE-SHOOTING Experience has proven that the best method of trouble-shooting is to decide on the various causes of a given trouble and then to eliminate causes one by one, beginning with the most probable. The following charts list some of the more common troubles, which may be encountered in maintaining engines;...

  • Page 62: Failure Of Engine To Idle Properly

    SECTION 6 LYCOMING OPERATOR’S MANUAL TROUBLE-SHOOTING O-320 SERIES TROUBLE PROBABLE CAUSE REMEDY Failure of Engine to Idle Incorrect idle mixture Adjust mixture. Properly Leak in induction system Tighten all connections in the induction system. Replace any parts that are defective. Incorrect idle adjustment Adjust throttle stop to obtain correct idle.

  • Page 63: Failure Of Engine To Develop Full Power

    LYCOMING OPERATOR’S MANUAL SECTION 6 O-320 SERIES TROUBLE-SHOOTING TROUBLE PROBABLE CAUSE REMEDY Failure of Engine to Develop Leak in induction system Tighten all connections and Full Power replace defective parts. Throttle lever out of adjustment Adjust throttle lever. Improper fuel flow Check strainer, gage and flow at the fuel inlet.

  • Page 64: Excessive Oil Consumption

    SECTION 6 LYCOMING OPERATOR’S MANUAL TROUBLE-SHOOTING O-320 SERIES TROUBLE PROBABLE CAUSE REMEDY High Oil Temperature (Cont.) Low grade of oil Replace with oil conforming to specifications. Clogged oil lines or strainers Remove and clean oil strainers. Excessive blow-by Usually caused by worn or stuck rings.

  • Page 65: Installation And Storage

    LYCOMING OPERATOR’S MANUAL SECTION 7 INSTALLATION AND STORAGE Page Preparation of Engine for Installation....................... 7-1 General................................ 7-1 Inspection of Engine Mounting ........................ 7-1 Attaching Engine to Mounts ........................7-1 Oil and Fuel Line Connections ......................... 7-1 Propeller Installation ..........................7-1 Preparation of Carburetors for Installation....................
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  • Page 67 LYCOMING OPERATOR’S MANUAL SECTION 7 O-320 SERIES INSTALLATION AND STORAGE SECTION 7 INSTALLATION AND STORAGE 1. PREPARATION OF ENGINE FOR INSTALLATION. Before installing an engine that has been prepared for storage, remove all dehydrator plugs, bags of desiccant and preservative oil from the engine. Preservative oil can be removed by removing the bottom spark plugs and turning the crankshaft three or four revolutions by hand.
  • Page 68 SECTION 7 LYCOMING OPERATOR’S MANUAL INSTALLATION AND STORAGE O-320 SERIES 2. PREPARATION OF CARBURETORS FOR INSTALLATION. Carburetors that have been prepared for storage should undergo the following procedures before being placed in service. Remove the fuel drain plug and drain preservative oil. Remove the fuel inlet strainer assembly and clean in a hydrocarbon solvent.
  • Page 69 LYCOMING OPERATOR’S MANUAL SECTION 7 O-320 SERIES INSTALLATION AND STORAGE Exterior Surfaces – All exposed cadmium plated and machined surfaces should be coated with soft-film corrosion-preventative compound (E. F. Houghton and Company, Cosmoline 1059 or equivalent). The starter ring gear and propeller mounting surfaces in particular should receive a liberal coating of the compound.
  • Page 70 SECTION 7 LYCOMING OPERATOR’S MANUAL O-320 SERIES INSTALLATION AND STORAGE Figure 7-1. Fuel Metering System...
  • Page 71 LYCOMING OPERATOR’S MANUAL SECTION 7 O-320 SERIES INSTALLATION AND STORAGE Figure 7-2. Magneto Connections...
  • Page 72 SECTION 7 LYCOMING OPERATOR’S MANUAL INSTALLATION AND STORAGE O-320 SERIES Figure 7-3. Optional Oil Cooler Connections...
  • Page 77 LYCOMING OPERATOR’S MANUAL SECTION 8 TABLES Page Table of Limits ............................. 8-1 Ground Run After Top Overhaul ......................8-2 Flight Test After Top Overhaul........................8-3 Full Throttle HP at Altitude........................8-4 Table of Speed Equivalents ......................... 8-4 Centigrade-Fahrenheit Conversion Table....................8-5 Inch –...
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  • Page 79 LYCOMING OPERATOR’S MANUAL SECTION 8 O-320 SERIES TABLES SECTION 8 TABLES TIGHTENING TORQUE RECOMMENDATIONS INFORMATION CONCERNING TOLERANCES AND DIMENSIONS THAT MUST BE MAINTAINED IN LYCOMING AIRCRAFT ENGINES, CONSULT LATEST REVISION OF SPECIAL SERVICE PUBLICATION NO. SSP1776. CONSULT LATEST REVISION OF SERVICE INSTRUCTION NO. 1029 AND NO. 1150 FOR INFORMATION PERTINENT TO CORRECTLY INSTALLING CYLINDER ASSEMBLY.
  • Page 82 SECTION 8 LYCOMING OPERATOR’S MANUAL TABLES O-320 SERIES FULL THROTTLE HP AT ALTITUDE (Normally Aspirated Engines) Altitude % S.L. Altitude % S.L. Altitude % S.L. H.P. H.P. H.P. 10,000 70.8 19,500 49.1 98.5 11,000 68.3 20,000 48.0 1,000 96.8 12,000 65.8 20,500 47.6...
  • Page 83 LYCOMING OPERATOR’S MANUAL SECTION 8 O-320 SERIES TABLES CENTIGRADE-FAHRENHEIT CONVERSION TABLE Example: To convert 20°C to Fahrenheit, find 20 in the center column headed (F-C); then read 68.0°F in the column (F) to the right. To convert 20°F to Centigrade; find 20 in the center column and read –6.67°C in the (C) column to the left.
  • Page 84 SECTION 8 LYCOMING OPERATOR’S MANUAL TABLES O-320 SERIES INCH FRACTIONS CONVERSIONS Decimals, Area of Circles and Millimeters Inch Decimal Area Inch Decimal Area Fraction Equiv. Sq. In. Equiv. Fraction Equiv. Sq. In. Equiv. 1/64 .0156 .0002 .397 .1964 12.700 1/32 .0312 .0008 .794...

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