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What is the resistance supposed to be on these coils??????should i measure across the posts (top and bottom) or should i read from each post to the center wire connection. The car ran pretty good before i started the tuneup. The coil has a 1/4 deep dent in the housing and i want to make sure the windings are ok (not touching).

Pat

For 6V systems the coil primary should be in the range of 0.9 to 1.7 ohm, the secondary 8,000 to 11,000 ohms.

Primary resistance measurement is made across the two low voltage posts, secondary measurement is from one of the low voltage posts to the the high voltage secondary output connection of the coil.

https://www.youtube.com/watch?v=dtMnD8YJo2Y

So in following the video im getting 1.5 Ohms post to post and 5.5KOHMS on the other so i would have to say the coil is shot???

Problem with just a resistance check is the coil can be quite different when hot and if the tar compound or whatever other insulation between the coils and can has been cracked or damaged with the dent it might not show up until a high voltage is present to jump over.

To rule out coil issues it might be easier to pick up a relatively inexpensive IC-7 from Napa and substitute. If the original works the same then use it and keep the Napa as an emergency spare.

HH56 yeah i may try that....im guessing that this coil is probably original, even painted and cleaned up its pretty rough......all the vendors are selling their coils for around 225......why so damn much????? are they original??????or just original style?

Some are original and some are labeled as rebuilt. I don't know of anyone reproducing the approx 35-47 coils that have the base terminal for an armored cable feed wire other than possibly KM Lifestyle. There is a photo of a Clipper style coil they made which looks as if they might have crimped some tubing on the end of a coil that could accept the end of the armored cable that is used on those models. Believe the conventional bodies take a different armored end so haven't seen their option for that type if they have one.

I know at least one of the vendors said they have had no comebacks with NOS coils but after that many years with something electrical sitting on a shelf it is hard to believe some deterioration has not taken place. How long they would work is a question and as for rebuilt, another question is what exactly constitutes a rebuild in something like a coil -- all new guts or just a paint and dent removal.

At least the Napa option is for a fresh and relatively inexpensive coil. Making a holder to use an IC7 on conventional bodies along the lines of the one I made for my Clipper is something I have toyed with but if KM has one that works for one type coil then they probably have it covered for the other.

I keep hearing about these coils and an 'armored' cable as being original issue in the late 30's, early 40's. On my '39 Six, I just had a standard looking coil that mounted in a bracket that LOOKS like original kit as it is bolted underneath the head bolts, but it just has a standard, plastic covered wire going between it and the ignition switch. Is it possible somebody switched this over to a more modern, available coil, or did some Autolite equipped cars come that way?? Are there any issues with this? Just curious as the 'armored covered cable' comes up again and again. I did replace my coil with a correct 6-volt unit that was supposed to be appropriate for my car and it didn't change anything.

Bonnie is a 1941 110 as far as i can tell its pretty original.Here are some pics of my coil and "armored" cable to the key switch.

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Thanks for the pics, Pat. My question is: if one does NOT have that type of coil (i.e. the top & bottom terminal type with the 'armored cable'), can it pose issues with operation??? If a previous owner has just gone ahead and changed it up to the more modern 'both wire terminals on top' type coil, with a regular, non armored wire, can it cause problems?? My guess it was the 'original way' for a reason??

No difference in operation as long as the coils are good. I don't know how many other mfgs used the wire inside the armored cable or if any kept it longer than Packard but the 21st series thru 47 was the last for Packard. 22nd series 48 models went to the modern 2 terminals exposed type coil.

The only reason for the wire inside the armored cable approach was it was harder to hot wire and steal the car if the terminal needed for the ignition power was not easily accessible. I doubt that really deterred a determined thief though -- just took them a few minutes longer.