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Well, yesterday we drove her 150 trouble free miles! It was a cool, rainy day here so that may have helped. I'm going to buy a aftermarket coil anyway(NAPA has one for $50) to carry along for now. I think I'll probably follow clipper47's advise and eventually mount it with a make-shift bracket.
Thanks to all for your help!!

Not a Problem! that is why were all here! to help each other out! Glad to hear you had a great outting!

Well, here's a question that I thought I knew the answer to, but now not sure. How do you tell which is the primary (or secondary) side of a replacement coil purchased at a parts store? This is important to know in connecting it. I believe that if the car is positive ground, for example, then the positive terminal goes to the distributor. But how do you know if the coil's positive is the primary or secondary? I hope all of this babble is not too confusing, but we often talk about getting a replacement coil at the local NAPA, like in this thread. Thanks.

primary winding is the one the cars harness connects to. seconday is what the coil wire attaches to. and yes, positve ground= positve terminal to the distriburor

greendragon, so replacement coils come in 6- or 12-volt, and negative or positive ground? You need to specify which voltage and ground your car is to get the correct coil, right?

All the universal coils I've seen are not polarity sensitive like a solid state component but you do have to specify voltage when buying. You then wire according to needs because terminals come marked either with the plus & minus such as this one or a red dot on the positive side. Some of the older OEM coils had one terminal labeled -- usually IGN or SWitch. Assuming it was installed in the specified car, polarity was assumed to be correct with that kind of label.

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greendragon, Thanks for this, but I think that a universal coil will not work universally. The primary and secondary windings are different. So, what would be the primary winding for a negative ground system would be the secondary on a positive ground system. This would result in what we used to call "reversed polarity". Ignition system performance will suffer with a coil connected incorrectly. You would have to know which terminal goes to which winding and install accordingly. A coil that only has + and - signs would not give you the needed information. Is there a way to test for identifying primary and secondary windings?

Sorry to be a pain about this, but I think it important, and I appreciate your time and efforts in pursuing this with me.

Can anyone else lend any light on the subject?

EDIT: I suppose one could install the coil according to the + and - marks, and then with the engine running test the secondary voltage output. One would need a milliamp meter to do this with one lead on a spark plug terminal and the other lead grounded. I do not know what the output amount should be. A way to do this would be to run the engine with the coil connected one way, take a reading, reverse leads and take another reading, and connect according to the highest reading. BINGO!

Here's a couple of brief articles on ign coil construction.

Looking at the schematics, I think the only way to possibly know best orientation without an ign scope on the secondary output would be to have an ohmmeter sensitive enough to pick up the additional .5 - 1.5 ohm of the primary winding reliably. The terminal with the least resistance to the tower terminal would be the one the secondary coil end is attached to--

Don't really think that method would work as I don't believe one could get a reliable reading with the difference of +/- 2 ohms in the secondary coils range between 7.5 - 10k.

A couple of articles mention some coils having the secondary end attached to metal case instead of the primary terminal but I don't know how common that is & don't recall ever checking for one. The description & picture in the Packard Ign training book almost makes one think the dash mounted coils may be constructed that way though.

http://www.delmarlearning.com/samplechapters/dl_display_sampchap.aspx?isbn=0766806731&cid=23

http://www.sentex.net/~mwandel/cannon/sparky.html

https://packardinfo.com/xoops/html/modules/article/view.article.php?46

OK HH56 and Greendragon are not the same person! please read the posts! And HH56 is correct! coils are voltage sensitive, but not polarity sensitive! and NO!!!! changing where the + and - are hooked up WILL NOT result in a reversed polarity system!!!! the SECONDARY windings which is what the COIL WIRE is attached to and the PRIMARY windings which is what the CAR'S HARNESS is attached to, do not actualy TOUCH TOGETHER!!!

greendragon I apologize referring to you as HH56. HH56, I apologize for confusing you with greendragon. HH56, thank you for your article references. I'll stick with my edit comments as that is how we used to check for secondary output and coil connections. Bye.