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Thanks r_d,
I will follow your directions tomorrow night and report back. -Tim "r_d" wrote in message . com... "TSC" wrote in message ... I have the Siloc book. I went through the troubleshooting, and I have no spark anywhere. Curiously, the wiring diagrams in the book do not show an external ballast resistor. I have following the wires from the coil and I cannot locate one either. The original coil (which I replaced) says the only use it with an external resistor. I made sure the new coil was for use with an external resistor. Any clues as to where the resisitor would be? Would a faulty resistor allow it to crank, but show no spark? Note that I checked for spark at the points, by pulling the coil wire and holding it near a ground, and by putting a spare spark plug into a plug wire. Trust me... there is no spark. Ok let me ask you this... Key on do you see 12v on the positive (+) terminal of the coil with the key on? If NO then hooking up a wire with gator clips from the positive (+) battery terminal to the positive (+) side of the coil. See if it will start if so pull the clip off if it dies then you have a problem with the external resistor. In this case just ignore it, go get a internal resistor coil and run a wire directly from the ignition switch to the coil. Don't use the external resistor coil on 12 volts it will overheat. You can in the future use this new 12volt wire to run the electronic pickup that you will eventually install in place of the points...... I suspect this is not your problem as it will not start even when the starter is running. If YES there is power to coil with key on then I would unhook everything from the negative (-) terminal of the coil except for the points (should be a single wire running from points/condenser to coil). See if it starts and runs. If so tach is dead or short in shift interrupt system. The way the coil works is such... the coil charges when positive power is on and the coil is grounding though the points. When the lobe in the distributor gets to the proper position it opens the points breaking the ground to the coil and the power stops flowing in the secondary circuit in the coil. When this happens it creates a magnetic pulse in the coil that is picked up by the primary circuit and is send out of the coil as a high voltage "jolt" that is then sent to the plugs. If the ground circuit is always grounded no spark or if the circuit does not close (no ground) no spark. I bet this is where your problem is in the system. During cranking the starting system will feed a full 12volts to the coil then when the starter is off it feeds ~10volts to the coil through the resistor circuit (voltage will depend on the resistor but should be between 7-10volts). From what I have read in your posts I bet you have a ground issue. I went though something similar last year with my OMC. Let us know how you make out. good luck, mark |
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