Packard Forum Index » V-8 (1955-56)

I'm in the process of putting my 55 400 back together. I'm trying to get it to fire for the first time in 49 years. The engine has been rebuilt (long story). The first step was to get wiring back so that the engine turned with the ignition switch. Found switch to be bad. Change switched. Okay engine turns with the key. But no, spark. New coil points and condenser from Napa. Installed the new parts and got spark from the coil wire, but now coil is heating up! Disconnect the battery. With the key out disconnected the ground wire from the distributor to the coil. Reattached battery ,touched wired to coil, spark. Somehow have bypassed the ignition switch - I think?? I have double checked the distributor wiring as well as the ignition switch both check out to wiring diagram. I really don't know where to check next. Any help would be deeply appreciated. Thanks. Happy

The V8 coil feed is from the ignition switch to the ballast resistor and then to the coil. There is a secondary feed directly from an aux contact on the solenoid which provides a straight 12v to bypass the ballast resistor and produce a hotter spark during starting. That feed is only present when the starter is engaged. Once the solenoid drops the starter out it also drops the extra feed to the coil and the coil then gets only the reduced voltage thru the ballast resistor.

On automatic transmission cars, the other coil terminal goes directly to the distributor where the points connect to ground to complete the circuit. On overdrive cars, in addition to the distributor wire there is another wire on the second coil terminal which will also connect to ground during kickdown. If there is a problem in that circuit it can also keep the coil energized and getting hot.

If the coil gets cool by disconnecting the distributor I would suspect either the points are not opening or else during the work inside the dist the small flexible cloth covered wire between points and the outside terminal has lost a chunk of the old fabric insulation and has become grounded. That has happened to more than one person on the forum. There is also a slim but still possible chance the new capacitor is shorted.

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Neighbor came over and helped troubleshoot my electrical problem. Found current leaking through the ignition switch in off the off position. Ordered new switch from Max. Should have it by the end of the week. Expect problem solved.
Thanks for the input, much appreciated.
Happy

Glad you found a problem. Don't recall anyone mentioning that particular ignition switch failure before but they have done crazy things so will have to add the symptom to the list. Strange the car wouldn't give some indication of trying to start with the coil on all the time though. Let us know if the new switch solves it.

Another issue is that your new coil is likely made in China. Better off with a salvage yard coil from a '70s US car. Ask me how I know!

I agree with 64avanti. I was looking for an Autolite coil when I was working on my 55 Clipper. Located one from a parts seller in California. It came off a Packard that had been out in a field for several years. Checked it out, seemed fine, installed it, and it worked with no problems. JWL