See the answer I gave in the next post down. A 6v coil will spark just fine and hot when operated on 10 volts (as when the engine is cranking, and the starter is taking 300 amps) The coil will get hot if operated on 14+ volts,(tractor starts and charging system works) and the points will deteriorate faster. So a resistor is placed between the ignition switch and the coil reducing the voltage to about 7 or so for continuous operation. To get full voltage (10 or so) when starting the resistor is bypassed. when cranking.
If the tractor has a mechanical starter switch, a bypass can be made to work as follows.
Take off the starter switch from the starter (if it is a saddle mounted type), or disconnect the lead from switch to starter at the starter if it is the big push button style.
Solder a #12 insulated wire to the side of the starter stud (saddle mount) and make a small "mouse hole" in the side of the saddle switch to get the wire out with out pinching when the switch is installed. If it is the big button style, just use a large diameter terminal end to attach a #12 wire to the starter main terminal. in this wire it is mandatory to place a Diode. This diode must be a 5 amp 500piv rated device. This diode prevents back flow into the starter blocking ignition voltage from flowing through the starter when the starter is not operating, but flowing full available battery voltage to the ign when cranking.
The polarity of the diode for negative ground will have the band on the side away from the starter. and on positive ground it will be toward the starter.
The far end of the diode will be attached to the #12 wire and extended to the coil side of the Ignition Ballast resistor.
To assure you have it connected with correct polarity an easy check is to wire everything but the diode, then, with the ignition off, use a jumper wire from the non-ground battery terminal to the diode then touch the other diode lead to the wire going to the far side of the resistor. if it sparks it is correct, passing voltage to the coil on cranking. If it does nothing it is wrong, and will just smoke the Ignition resistor when the starter motor acts like a ground to the ignition voltage when running. Best of luck, Jim
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Today's Featured Article - George's Fordson Major - by Anthony West (UK). This is a bit of a technical info to add on to the article about George's Major in the "A Towny Goes Plowing" article. George bought his Major from a an implement sale about 18 years ago for £200.00. There is no known history regarding its origins or what service it had done, but the following work was undertaken by Harold alone to bring it up to show standard. From the engine number, it was found that the major was produced late 19
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