1 / 32

Chapter 9

Chapter 9. Ignition Systems page 147. Basic Ignition System Operation. charge builds up in coil (12 volts in) creates a magnetic field (windings of wire) voltage is stepped up (secondary windings) switch open (magnetic field collapses) high voltage discharged (to plug).

ezekiel-larson
Download Presentation

Chapter 9

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 9 Ignition Systems page 147

  2. Basic Ignition System Operation • charge builds up in coil (12 volts in) • creates a magnetic field (windings of wire) • voltage is stepped up (secondary windings) • switch open (magnetic field collapses) • high voltage discharged (to plug)

  3. Fundamental Electrical Principles • Electricity is lazy • Electricity wants to go to ground • electron theory (-) to (+) • conventional theory (+) to (-) • Conductors • Insulators

  4. The Electron Theory • Electricity moves from – to +

  5. Electrical Units of Measurement • Volts---- Push V • Current ---Quantity A • Resistance ----Resistance to flow 

  6. Ohm’s Law • E = I x R • E / I = R • E / R = I E I R

  7. Magnetism • Alike charges repel (-) (-) • Dissimilar charges attract (-) (+)

  8. Magnets & Electricity • Magnets can be used to for electricity • Electricity can be used to form magnets • Electricity when applied to magnets make stronger magnets

  9. Ignition Coils • Coils of wire wrapped around an iron core • Step up transformer

  10. Spark Plugs • Spark plugs contain an air gap for electricity to create a spark and make a seal

  11. The difference between a "hot" and a "cold" spark plug is in the shape of the ceramic tip. Heat Ranges • The manufacturers will select the right-temperature plug for each engine. • Some engines with high-performance naturally generate more heat, so they need colder plugs. • If the spark plug gets too hot, it could ignite the fuel before the spark fires • It is important to stick with the right type of plug • Engine that burn oil may need hot plugs

  12. Measuring Spark Plug Temperature

  13. Types of Electrodes • Center electrode • Side electrode

  14. Switching Devices • Breaker points • Electronic

  15. Breaker Points • Ran by cam shaft

  16. Electronic Switching Devices • NO breaker points to burn or wear out

  17. The MBI Magneto System • Mechanical Breaker Point Ignition • produce power without an outside power source • Condenser-prevents arching

  18. The MBI Magneto Cycle • Magnets pass legs

  19. Coil • 150 turns of large wire • 20,000 turns of fine wire • Iron core

  20. The Stop Switch • Plug only fires when points open • Switch grounds points • Fasten metal to head bold

  21. Ignition Advance Systems • Cause spark earlier • BTDC • As engine warms up • Speeds up • Centrifugal • Vacuum • Mechanical

  22. Dwell & Cam Angles • Time points stay closed • Lobes size = dwell time

  23. Electronic Ignition • Solid state • No maintenance • No points-burning • Spark plug life • Easy starting • Higher output • Starts flooded engine • Higher spark output

  24. Electronic Ignition • Hermetically sealed • Uniform performance • Good under adversity • Improved idling • Smoother power under load

  25. Operation of Capacitive Discharge Ignition ( CDI) • Solid State • Newest • NO Breaker points • Magnets only moving parts

  26. Operation of Transistor Controlled Ignition (TCI) Systems

  27. Magneto Ignition Systems Compared

  28. Battery Ignition Systems • Low voltage primary circuit • High voltage secondary circuit • ignition switch • builds field • field collapses • spark to plug

  29. High Voltage Secondary Circuits • Uses a step up transformer • Several winding of wire / iron core

  30. Auto-Transformer Type Ignition Coils

  31. The Lead Acid Battery

  32. Vehicle batteries

More Related