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On Sun, 2006-09-03 at 22:01 -0500, Jim Adney wrote: > On 2 Sep 2006 at 18:06, Constantino Tobio wrote: > > > So, my 73 Fasty won't start. From the looks of it, I'm not getting > > spark- holding the coil wire near a ground shows no spark whatsoever, > > and I smell fuel in my exhaust, so I'm pretty confident that the fuel > > part of the operation is good. > > > > I get voltage to the coil- on both sides, but I also get voltage on > > both sides when the points are open. I tested out the points and > > they're not shorting. I swapped in a new condenser, but this was just > > throwing parts at the issue- both condensers are Bosch, as are the > > points. > > > > Disconnecting terminals 1 and 15 of the coil, and putting a multimeter > > across both lugs, gives me a resistance of zero ohms, and running the > > meter for continuity test shows it's indeed continuous across the two > > lugs. Resistance from each lug to the coil wire connector is around 8k > > ohms. I'm reading that resistance across 1 and 15 should be more like > > 20,000 ohms. > > Some time ago, I worked up a mathcad program to show the spark energy > as a function of RPM and coil style for the stock VW/Bosch coil and > the German Bosch Blue coil. I measured several stock coils to get an > average and came up with a primary resistance of 3 Ohms and a > secondary resistance of 9.3 kOhms for the stock VW/Bosch coil, so > your numbers don't sound that bad. > > The zero you measure for the primary makes me wonder whether your > Ohmmeter just isn't on a low enough scale (or doesn't have such a > scale. For comparison, you need to measure something else that has a > known resistance in that same range. Measuring between the 2 posts on > the generator (with the DF wires off) should give you 3.5-4 Ohms, > IIRC. > > > So, indeed it appears that my coil would be shorted across the two > > windings somehow. > > OR, a broken lead on the points, or a distributor with a bad ground braid on the plate, or something is not hooked up right in the point circuit. -- russw <russw@classicvw.org> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ List info at http://www.vwtype3.org/list | mailto:gregm@vwtype3.org ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~