Small Gas Engine Troubleshooting and Tune-up Introduction Small gas engines are a vital aspect of many businesses, used for a variety of power demanding tasks. Most of these engines take heavy abuse daily. Due to the rough conditions in which these small engines must operate, it is essential that scheduled maintenance procedures be followed. Without proper maintenance, a small gas engine can be ruined in a very short period of time. This video will explain the trouble-shooting and tune-up techniques needed to properly maintain these small "power plants." You will learn how to service a small engine's fuel system, ignition system, lubrication system and more. To be a successful small engine technician, you must be able to diagnose and repair any engine malfunctions. This program will provide you with the information needed to accomplish this task. Student Objectives After viewing this video, you will be able to: • Inspect a small gas engine for any type of fluid leaks. • Check a small engine's compression level. • Test the operation of a small gas engine's ignition system. • Explain how to test the operation of a small engine's fuel system. • Examine a small engine's exhaust smoke to determine engine condition. • Service a small gas engine's ignition system. • Service a small engine's fuel system. • Clean or replace a small engine's air cleaner. • Service a small gas engine's lubrication system. • Inspect and service a small gas engine's cooling system. To The Instructor This video is designed to be a valuable supplement to your curriculum. Since young people are extremely acclimated to television, it is a natural way to help present important aspects of your subject matter. This video is designed to give a detailed, yet broad coverage of the topic. Most educators agree that it is best to use as many instructional methods as possible. Utilize quality textbooks, workbooks, videos, lectures, demonstrations, overheads, and other methods to present the technical information. This will hold interest and help pupils understand the large amount of information required to succeed in today's complex world. This video is organized into major sections or topics. Each section covers one major segment of the subject. Graphic breaks are given between each section so that you can stop the video for class discussion, to answer critical questions, to ask questions or perform in-class demonstrations with actual components or parts. This program's format is arranged to be extremely flexible. View it as a full length program, a supplement for lectures, or demonstrations for self-paced individualized instruction. This video allows you to watch only a portion of the program each day or the complete video, depending on your curriculum requirements. The program is designed to simplify the complex. Concise wording and carefully selected graphics are used to provide maximum learning in minimum time. Close-up shots of components and service procedures are used to make every second of viewing instructional, as if each student was standing right behind you, watching over your shoulder while you were working or giving a demonstration. Our technical visual images are designed to match the audio so that every scene has maximum educational value. Computer animation is used to explain difficult to comprehend principles or techniques. Students seem to enjoy the cartoon type images that show how parts work, how they fit together, or how they vary in design. Quiz Answer Key 1. a 2. c 3. a 4. d 5. d 6. c 7. b 8. a 9. c 10. d 11. c 12. a 13. b 14. c 15. c Use your own judgment to evaluate the definitions, definition type questions, and discussion topics. Technical Terms Write definitions for the following terms. Use a textbook or review the video if needed. carburetor fuel bowl, engine compression, fuel system, ignition system, lubrication system, cooling system, rod knock, electronic stethoscope, piston slap, piston pin knock, engine horsepower , engine model number, engine spec number, spark test, spark tester, spark plug, wire feeler gauge, contact points, condenser, point gap, ignition coil, magnetic field, electronic ignition system, electronic ignition module, ohmmeter, ignition coil resistance, ignition coil primary windings, engine flywheel, timing marks, timing light, ignition timing, fuel filter, two-stroke cycle engine, four-stroke cycle engine, carburetor float, carburetor needle valve, carburetor fuel mixture, high speed jet carburetor, connecting rod, crankshaft, American Petroleum Institute rating, oil dipstick, dipstick tube, oil pan sump, engine crankcase, oil filter, cylinder cooling fins, flywheel air inlet screen, engine shrouds, air cooled engine, liquid cooled engine, cooling system pressure tester, voltmeter, distilled water, battery post cleaning tool, engine charging system, tire gauge, grease fittings Video Discussion Topics Here are a few topics that might be used for a class discussion. 1. What safety rules should be followed when servicing a small gas engine? 2. Name some other causes or a carburettor leak on a small gas engine. 3. Describe how to test the operation or a small engine's ignition system. 4. How can dirty motor oil damage a small engine? 5. Explain how to install contact points and a condenser on a small gas engine. 6. Why is it important to know the engine identification numbers when ordering replacement parts for a small engine? 7. Why should you drain the gasoline from a small engine before storing it? 8. What precautions should be taken to prevent an "air cooled" small engine from overheating? Video Quiz Print the appropriate letter in the blank to indicate the most correct answer after reading the statement: 1. _____________ leaks often form a brown deposit under the fuel bowl. a. Carburettor b. Oil c. Cylinder d. Exhaust 2. Without ____________ pressure, a small engine's crankshaft will spin freely with little resistance. a. fuel b. oil c. compression d. crankcase 3. A ___________ spark plug indicates flooding from a closed choke, high float level or other problem. a. wet b. dry c. hot d. cold 4. A ____________ spark plug may indicate that fuel is not entering the engine's combustion chamber. a. wet b. hot c. cold d. dry 5. ____________ exhaust smoke indicates oil is being burned in the small engine's combustion chamber . a. Brown b. Gray c. White, d. Blue 6. ___________ smoke coming from a small engine's exhaust would indicate water in the fuel system or an internal engine leak in a "liquid cooled" engine. a. Brown b. Blue c. White d. Black 7. A rod knock is caused by wear between the connecting rod bore and the ________ journal. a. valve b. crankshaft c. camshaft d. piston 8. A piston slap is caused by excessive _____________ to __________ CV axle clearance. a. piston, cylinder b. piston, crankshaft c. piston, camshaft d. piston, head 9. Valve train noise is due to too much clearance between the rocker arm and __________. a. crankshaft b. camshaft c. valve d. lifter 10. If a small gas engine's ignition system fails a spark test, it may be necessary to test the ignition __________. a. switch b. coil c. module d. all of the above 11. When installing a new fuel filter on a small gas engine, make sure any arrows face toward the ________ and check to see if the filter is secured properly. a. head b. governor c. carburetor d. breather 12. If a small engine's carburetor body is worn or damaged, it 1SOften more cost effective to replace the ___________. a. carburetor b. float c. bowl d. gaskets 13. When installing a new oil filter on a small engine, wipe motor oil on its ________ and tighten the filter with your hands. a. bracket b. seal c. element d. none of the above 14. Most new small gas engines are equipped with a(n) _________ to properly check engine oil level. a. gauge b. tube c. dipstick d. plunger 15. With air cooled small gas engines, a high volume of air must be drawn over the cylinder cooling fins by a fan on the engine _______________. a. shroud b. block c. flywheel d. crankshaft Short Answer Briefly answer the following questions in your own words: 1. What obvious problems should you look for when trouble- shooting a small gas engine? 2. List the five operating requirements needed for a small gas engine to start and run properly. 3. What is indicated if black smoke is detected in a small engine's exhaust? 4. How can a small engine's "valve train noise" often be corrected? 5. Describe how to properly install a spark plug in a small gas engine. 6. Name two possible places where "contact points" can be located on a small engine. 7. Describe the basic procedures used to test the operation of a small engine's ignition coil. 8. What is basically involved when performing a carburettor rebuild on a small gas engine? 9. Explain two common techniques used to adjust the "high speed" screw on a small gas engine's carburettor. 10. Why should a small engine's air cleaner be periodically serviced?