A compilation of key maintenance and performance articles taken from the former Lycoming Flyer Newsletter Lycoming Flyer Key Reprints
D e a r Lycoming Flyer C u s t o m e r, O u r K e y R e p r i n t s i s o n e o f L y c o m i n g s m a n y u n i q u e a s p e c t s t h a t m a k e o u r c o m p a n y s p e c i a l. F o r t h o s e w h o h a v e b e e n i n a v i a t i o n a l o n g t i m e a n d f o r t h o s e w h o a r e j u s t d i s c o v e r i n g g e n e r a l a v i a t i o n s w o n d e r s, f u n, a n d e x c i t e m e n t, y o u w i l l q u i c k l y r e a l i z e t h a t o u r e n g i n e s a r e t r u l y l i v i n g o r g a n i s m s. A s w i t h a n y l i v i n g o r g a n i s m, b e t t e r u n d e r s t a n d i n g a n d c a r e o f t h e p r o d u c t w i l l e n s u r e m a x i m u m p e r f o r m a n c e f o r e v e r y f l i g h t a n d f o r t h e l i f e o f t h e e n g i n e. F o r o v e r 7 5 y e a r s L y c o m i n g h a s b e e n d e s i g n i n g, t e s t i n g, a n d a s s e m b l i n g e n g i n e s. A s a c o m p a n y w e h a v e a b o d y o f k n o w l e d g e a b o u t o u r p r o d u c t s u n p a r a l l e l e d i n t h e i n d u s t r y. W e t h u s h a v e a r e s p o n s i b i l i t y t o s h a r e t h i s k n o w l e d g e w i t h y o u a n d h o p e y o u l e a r n a s m u c h a s p o s s i b l e a b o u t h o w o u r p r o d u c t s w o r k a n d t h e n e c e s s a r y c a r e a n d f e e d i n g o f e a c h m o d e l. L y c o m i n g s K e y R e p r i n t s i s o u r e f f o r t t o c o n t i n u a l l y s h a r e o u r b e s t p r a c t i c e s, k e y l e s s o n s, a n d e n g i n e s s y s t e m s k n o w l e d g e t o e m p o w e r o u r c u s t o m e r s. P l e a s e e n j o y L y c o m i n g s K e y R e p r i n t s. R e a d, l e a r n, a n d b u i l d o n y o u r b o d y o f k n o w l e d g e a b o u t h o w o u r e n g i n e s l i v e a n d b r e a t h e. T o k n o w m o r e a b o u t o u r e n g i n e s a n d h o w t o c a r e f o r t h e m, w i l l n o d o u b t m a k e b e t t e r p i l o t s a n d m a i n t e n a n c e p r o f e s s i o n a l s a r o u n d t h e w o r l d. A f e l l o w p i l o t, I a n W a l s h V i c e P r e s i d e n t & G e n e r a l M a n a g e r L y c o m i n g E n g i n e s
I N D E X The articles contained herein are not intended to supersede manufacturers service publications, instructions or manuals or any other official publications, but are provided in order to augment or explain in pilot s or mechanic s language these publications, as well as provide other supplemental helpful information for our customers and operators. G E N E R A L Facts About the Flyer and Key Reprints Some Definitions of Terms How to Get Lycoming Engine and Accessory Maintenance Publications Determining Engine Condition of High-time Piston Power Plants Questions Asked by Pilots and Mechanics Definitions Applicable to TBO, Engine Replacement and Engine Rebuild Oil Analysis What is an Aerobatic Engine? Low-compression Engine Grade 100 Aviation Fuel Fuel Contamination Do Not Use Automotive Gasoline in Lycoming Aircraft Engines Let s Talk Turbocharging Information About Lycoming-approved, Full-flow Oil Filters Detonation and Preignition Nitriding What is it? Compression Ratio An Explanation as it Relates to Lycoming Engines Watts Horsepower Cutaway of a Four-cylinder Power Plant Your Engine and the Fixed-pitch Propeller Induced Engine Damage The Whistle Slot Welding is not Recommended Engine Balance Fuel Injector or Carburetor The Same Engine Myth The Unfortunate Choice Low-time Engine May Not Mean Quality and Value In Search of Badly Behaving Baffles and Seals 6 8 8 9 10 11 13 14 15 17 17 18 19 19 20 21 21 22 22 23 25 26 26 27 28 29 30 31
O P E R A T I O N S Hard Facts About Engine Break-in Leaning Lycoming Engines Proper Leaning at Cruise Aids Safe Flight and Saves Dollars Operating the Direct-drive Fixed-pitch Lycoming Engine Operating Your Lycoming Engine at Takeoff and Climb The Exhaust Gas Temperature (EGT) and Fuel Management Landings and Takeoff from High-elevation Airports Basic Power Sequence An Explanation of Power Settings Considerations for Low-power Low-RPM Cruise Induction Icing Cold-weather Operations National Transportation Safety Board Warning on Simulated Engine-out Maneuvers Importance of the Cylinder Head Temperature More on Cylinder Head Temperature Interpreting Your Engine Instruments Engine Starting Suggestions Use of Fuel Boost Pumps with Lycoming Engines Avoid Sudden Cooling of Your Engine Sticking Valves Do Not Neglect the Warning Signs Operational and Maintenance Procedures to Avoid Sticking Valves Tips from the Hangar The Pilot and Turbocharging TBO Tradeoffs or Tips from Fred Thieves of Aircraft Engine Power Wet Air Effect on Engine Power Frequency of Flight and Its Effect on the Engine A Review of Old Wives Tales Spark Plug Fouling Engine Instruments: To Believe or Not to Believe Oil Flow Screens, Filter, Cooler and Pressure Relief Test Your Knowledge on Engines 36 36 39 39 40 40 42 43 43 44 47 48 51 51 52 52 52 53 53 54 55 56 57 61 62 64 65 65 66 66 67 69
M A I N T E N A N C E Mechanic s Creed The Basics Of Maintenance in General Aviation Ask About Reference Publications Before Your Engine is Taken Apart Air Filter Maintenance Oil and Your Engine Oil and Filter Change Recommendations More About Oil and Your Aircraft Engine Maintaining Oil Levels of Wet Sump Engines Tips for Changing Your Spin-on Oil Filter Suggestions if Metal is Found in the Screens or Filter Safety Tip Sealant Use Understanding Engine Color Codes Reciprocating Engine Break-in and Oil Consumption Limits Compression Check as a Maintenance Aid Spark Plugs Key To Smooth Engine Operation, I Spark Plugs Key To Smooth Engine Operation, II Is Your Spark Plug Connector Overtorqued? Why Rotate Spark Plugs? Maintenance Suggestions From the Lycoming Service Hangar Engine Hoses Checking and Adjusting Dry Tappet Clearance on Lycoming Engines Some Tips on the Lycoming O-235 Engine Importance of the Correct Base Nut Tightening Procedure Fuel Injector Nozzles Have Been Improved Unauthorized Additions to Your Engine Can Cause Trouble A Simple Check of Internal Engine Timing Installation of Counterweight Rollers Safety Notes Engine Suggestions for Operators Recommendations for Aircraft or Engine Struck by Lightning Recommendation Regarding Use of Incorrect Fuel Propeller Ground Strike or Sudden Stoppage Can Be Dangerous Keep Your Direct-drive Engine Starter Clean to Avoid Trouble 74 74 75 76 76 77 77 79 79 80 81 81 81 84 85 86 88 88 89 90 90 91 91 92 92 93 93 94 94 94 95 95 95
Notes on Replacing Connecting Rods or Pistons Does Your Nose Seal Leak? Cam and Tappet Wear Exhaust System Maintenance Pay Now or Pay Later High Time Cylinders Top Overhaul? Lycoming Model Codes for Reciprocating Engines 96 96 97 98 99 99 100 F R E Q U E N T L Y A S K E D Q U E S T I O N S Lycoming Overhaul Engine FAQ Lycoming Cylinder Kit FAQs Lycoming Roller Tappet Technology FAQs Lycoming-IO-390 FAQs Lycoming-IO-580 FAQs 104 105 106 107 108
Lycoming has been pleased and impressed by the number of requests for copies of the Key Reprints pleased by your many favorable comments concerning it, and impressed by the thirst for knowledge by operators of General Aviation aircraft engines. In the event a reader perceives a conflict between the content of these articles and the content of the current manuals, service bulletins or service instructions, the latter items govern, but the reader should contact Lycoming Service and bring such a conflict to our attention. The service bulletins and parts of the manuals are FAA approved; these articles are not. Some of the articles published are based on information contained in Service Bulletins, Service Instruction, and Service Letters. In addition, other articles are taken from actual field test data carried on by Lycoming personnel. Furthermore, the Lycoming factory is a central collecting agency on its aircraft engines in the field. Experiences and information from all over the world provide feedback that is recorded and analyzed. We share this information with our readers in the Flyer and Key Reprints. During the preparation process of each article and as each subsequent re-issue updating of information is part of the procedure. After articles are written, each one is carefully screened and checked by management, engineering and service personnel to ensure accuracy before being released for publication. The Flyer does not have an established publishing date for each issue. The latest issue is Number 53. The original concept of the Flyer has not changed since the first issue was published in 1964. Approximately 85% of the prepared text deals with technical information related to Lycoming engines, and the remaining 15% covers general newsworthy items. Distribution of the Flyer is made to owners and operators of Lycoming powered aircraft, authorized distributors and others who write us and request that we place them on our mailing list, with all costs of printing and mailing absorbed by Lycoming. It is the intention of Lycoming to continue to make available service, maintenance and operational data in the Flyer and Key Reprints to assist the owner and operator in improving their engine s performance and reliability. S t a t e m e n t o f C o p y r i g h t This material is copyrighted under the laws of various countries including the United States and Canada. No reproduction is authorized. Violation of copyright laws may render unauthorized copiers subject to penalties of up to $50,000.00 per unauthorized copy.