From reading the manual I understand a bit more of how it works, but still have some questions.<br /><br />first of all, 1970 800 80 HP, early 278*** serial number, battery CD, distributor,single coil inline 4.<br /><br />according to the book, the switchbox has an inverter, and ramps up the battery voltage to higher voltage AC ( approx 120 Volts AC) to saturate the coil.<br /><br />and then the distributor somehow triggers a switching transistor inside the switchbox to drop the primary circuit on the coil, and thru magnetic induction a very large voltage is induced into the secondary circuit and seeks it path to ground thru the spark lead leaving the coil.<br /><br />Now what I dont really under stand is why the coil is charged with 120 V AC? <br />dont most ignition circuits charge the coil with 12V ( battery voltage)?<br /><br />also how does the distributor work? I under stand there is a small voltage present and as the rotor spins the windows in the plate pass over the coils, and some type of signal is sent to the switch box every time this happens ( 4 times per engine revolution)<br /><br />BUT is the voltage sent from the switchbox and only returned when the distributor window lnes up?<br />or is the signal sent to the switchbox actually induced by the coils as the window passes over?<br /><br />and lastly,<br />on testing my own engine, the switchbox as a 1.6VAC output to the coil, a nearly battery level output to the distributor (11.5 VDC) and the coil has almost no resistance on the primary, (0.2 ohms)<br /><br />and about 350,000 ohms across the secondary.<br />does this mean these components are faulty?<br /><br />I have done alot of reading and searching and there isnt much information available for these old engines, and even less about the inner workings of the ignition components, source after source tells me to take it to a certified service center for testing.<br /><br />I would much rather understand how it works so that I can better maintain the engine for years.<br /><br />sorry for such a long post, and thanks for any help/ideas in advance!
