Packard Forum Index » Pre-War (1899-1942)

Recently got my 1940 356 Packard running after many problems with ignition system. Took it out for test ride a few miles or so and all went well. Returned home and set manual idle at 1100 RPM's an let run. Wanted to do this test before taking it out on highway to be sure engine would preform at higher RPM's for an extended length of time. Kept an eye on temp and oil pressure and they looked good. Then after about 10 minutes the engine started to miss badly and was unable to keep it running. Like before this seems to be an ignition problem. Checked everything and even pulled distributor reset points and tested to insure breaker plate was grounded (even put jumper from upper distributor body to engine block) all to no avail. Tested coil at coil wire with KV tester which showed only 8K or so. This seams low, however, primary winding post checked out at 1.2 ohms resistance and the resistance from primary to coil posts was 8K. These readings seem OK or are they? One thing I have done a number of times was forget to turn off ignition key for a few hours. This resulted in the coil getting very hot around 160 degrees. Could this oversight result in a coil failure? Maybe this is what happened when I left the engine running at 1100 RPM"s? If so, would think this would then be a common problem when outside temperature is high and one is stuck in city traffic. Vapor lock is not an issue as having the same problems when trying start engine in morning with electric fuel pump. Any thoughts?

Coil tests are generally almost completely useless in diagnosing coil health. The most common symptom of impending coil failure is that all is great when the engine starts up cold, and ignition gets erratic as the coil heats up. Simple enough to check - just go to NAPA and get a proper coil and hook it up temporarily and go for a test drive. Just been down the same road with a coil on my 34. Leaving the ignition probably didn't do any harm, and anyway it would depend on whether the points were open or closed at the time; generally points will suffer more than anything else.

Thanks,have purchased a new 6 volt coil and "hot wired" it. Had the same problem as with the NOS installed coil. So I'm thinking it's not the coil. At this point I'm at a loss why the engine went from smooth running to very rough and finally stopping. On re-start, which is now very difficult,engine now goes immediately to very rough to stopping again. Thinking the timing chain may have "jumped" but setting the TDC mark on the damper pointer the rotor lines up with the #1 post on the distributor cap, so I guess that's not the problem. Keep coming back to the grounding of the points but have checked the distributor a number of times to ensure proper grounding. Have another set of points and condenser so maybe I should try them?

I vote for the plugs having fouled due to rich mixture on the extended idle. Very close in second place would be the condensor, a technology which the Chinese have seemingly never mastered. Third would be to give the points a couple of licks with a point file.

I once had a 48 Custom here and needed to make several brief cold starts over the space of 3 days. At the end it would hardly run till I cleaned the plugs.

I would vote for the condenser.