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Terry, I'm not so sure I agree with what the parts guy told you... I may be wrong, but I don't think that working the tractor hard is going to put enough more load on the ignition system to cause the ballast resistor to fail. Maybe, but I don't think so. Sometimes, ballast resistors do "go out", but I think it is more a function of time (hours of use) and cycles (startup-run and shut down) than of engine load. I think he is dead wrong on telling you that the ballast resistor will feed 12 volts to the coil if it "goes out". The way a ballast resistor works is this: A ballast resistor is nothing more than a coil of higher resistance wire inside a ceramic block case. (Think of a 3/4 inch garden hose spliced together with a short 1/4 inch piece of pipe to splice it together...when water is flowing through the hose, the 1/4" pipe will resist the full flow of water through it and as a result you have lower pressure at the nozzle. That's basically the same way a ballast resistor works-it is the 1/4" piece of pipe in the hose.) The coil of wire "resists" electricity flowing through it as freely as it would through a copper wire. So, as the electricity flows through the coil of wire, it absorbs some of the electrical energy and converts it into heat, and as a result, the resistor gets HOT. Over time and repeated HOT/COLD cycles, the wire inside the resistor eventually weakens and breaks or burns through. What you then have is an open circuit, and NO electricity makes it to the coil because of the broken coil inside the resistor. It's the same result as if you cut the wire. The reason the new resistor smoked when you put it on is because it was getting hot and the protective coating on the coil of wire and the outside of the ceramic block was burning off. It's a normal occurrance with a new resistor. What I would do if I were you is put on the new coil that he gave you and also the new ballast resistor, because they likely are matched up so that you have the proper impedance for your ignition system. What that means is better reliability, because the resistor will reduce the voltage (pressure in the hose analogy) to the proper level for the coil and as a result the coil is happy and the resistor is not working so hard and getting so hot that it smokes. When you get all the numbers right, everything works a long time before it breaks again! Just my opinion, probably worth about what you paid for it! :-) Brian
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