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Chuck, to answer your question how to test a condensor, its basically an open circuit to DC and should NOT show a short between its leads. (if its a short circuit to DC its bad) If you have an analog ohm meter you can set it on the x 10,000 scale, discharge the condensor first, and then when you apply the ohm meter it should start to swing towards zero ohms as the condensor initially starts to charge and conduct, but then swing back to infinity ohms. However, thats NOT the usual suspect when the ignition does not work. The more usual problems are bad (open) coils or bad points. Here are a few troubleshootong tips using volt meters or even an inexpensive test lamp. PRELIMINARY Make sure both sets of points are gapped proper and NOT burned or pitted or carboned up and if so, replace them. If only gray oxide coated but otherwise smooth you may get by if you clean/polish them. Make sure you have power to the unit when the ignition is turned on. The coils low voltage primary sides MUST be a continuous circuit, they can burn up and open if left on too long and get hot. TROUBLESHOOTING 1) Turn on the ignition and verify you have power going to it, due to a current limiting ballast resistor in the ignition circuit plus dependign upon if the points are closed and conducting, the voltage could be somewhat less than battery voltage, but there must be power present to work. 2) Open the points, or have them held open with an insulator like paper or plastic, or have them open on high cam, and there should be near battery voltage on their wiring terminal. Thats cuz when open theres no conduction path to ground (except for the test lamp or volt meter). If they dont show voltage there, the coil may be burned/open which can happen. If they do show voltage when open, the coils primary is continuous which is a good thing. 3) If they DO NOT show voltage, the coils primary may be open, or theres no power getting to the ignition unit, or theres an open ballast resistor. Use a test lamp or voltmeter and trace backwards (with points open) to see where power is and where it stops, like if its on the coils input but not output (to the points), the coils open. I believe you said the unit has power going to it, so the coil may indeed be bad/open. Unhook the condensor and if it then has voltage but didnt with it in place, its shorted. Also, look for any shorts or bad/freyed wires going to the points or any shorted spring assembly etc which may be shortign out the power to the points. 4) Now, if they do show voltage allow them to close (remove insuator between points or take off high cam etc.) and the voltage on the points terminal should then go to near zero and/or a test lamp go OFF. If you place a test lamp on the points terminal as the engine rotates the lamp MUST flash ON (points open) and OFF (points closed) for her to ever fire. If the voltage does not go to zero and test lamp go off when the points are closed, the points may be bad like carboned or burned or are not getting a good ground path. 5) If a test lamp or voltmeter on the points flashes on and of as the engine rotates, there's power to the unit and to and through any ballast resistor, the coil has continuity, the points are basically doing their job, and the condensor or points or wires are not shorted out. 6) If all that passes but she wont fire the plugs and they and the plug wires and cap etc are all good, the coil could be bad in its high voltage secondary side, although they burn up low voltage primarys more common. Do the test lamp or voltmeter checks at the points and let us know what you find and we will proceed from there. Make sure power is present to the unit, and then see what happens on the points terminal as they are open and closed and post back. Good Luck n God Bless John T Nordhoff
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