Understanding and Troubleshooting Your Tractor's Electrical System
Briggs & Stratton Master Service Technician,
Simplicity Dealer, Kohler Dealer, and Tecumseh Premier Dealer
This series of articles will attempt to address some of the mysteries that surround electrical problems. As I go to service meetings, almost all of the manufacturers, both engine and equipment, focus on electrical problems. If it is a problem for technicians, it must be even tougher for consumers. I will start out with some VERY basic electronic theory, and then adapt it to wiring, solenoids, charging systems, etc. Please be patient and if this is too boring at the beginning, just tune it out. I believe that if you can understand what is happening when an electric current flows you can easily understand what is happening in all electrical devices.
Electricity 1, Basic Matter. To understand electricity we need to understand "matter" and some basic electrical charge characteristics. It discusses negative and positive polarities, electrons and protons in the atom, the relationship of magnetism, and how an electrical current flows at the molecular level.
Electricity 2. This article describes the basic electrical concepts of electromotive force (voltage), current (amperes), resistance and power, and their basic relationships.
Electricity 3. This article describes how these basic electrical properties are measured (volts, amperes, and Ohms). It covers the only two "laws" that you really need to know and understand, in order to solve the most common electrical problems on your tractor. It also introduces the electrical symbols used in schematics and wiring diagrams.
Electricity 4. Series and Parallel Circuits. This article looks at simple series and parallel DC circuits and illustrates the relationships occurring between Voltage, Current, Resistance and Power.
Electricity 5. Magnetism and Electric Current. This article looks at the relationship between magnetism and electrical current. It explores the basic principles of how magnetism can be used to convert electrical current to mechanical energy or how magnetism can convert mechanical energy into electrical current.
Starter-Generator. This article describes the starter generator assembly, how it is made, how it works, how to test it and how the voltage regulator controls it.
3 Pole Regulator. This article describes the voltage regulator commonly used with the long-frame starter-generator on horizontal crankshaft engines in tractors such as the Landlord or Sovereign. It provides an understanding of how they operate, in addition to a detailed description, to help you troubleshoot them.
2 Pole Regulator. This article describes the different voltage regulator commonly used with the short-frame starter-generator on vertical crankshaft engines in tractors such as the Broadmoor, Yeoman or Serf. See the 3 Pole regulator article, above, to understand how regulators function.
I hope you find this information valuable! Your friend and fellow club member . . .
Edited by Kent