Are you by chance using one of the Mallory "variable" ballast resistors? As advertized they are supposed to have a low start-up (cold) value and gradually change up to 1.5 OHMs. I originally thought that would be a good idea - but the part was not only inconsistent - but ultimately failed "open". Replacing it with an MSD .88 OHM unit resulted in instant relief. 

 
 Steve Metzger       Tucson, Arizona

Another shot in the dark.

Run a jumper wire from the battery + ( positive post ) to the distributor to by pass the resistor and the ignition switch. CAUTION you no longer have neutral start switch protection and the can AND WILL start while in gear.

You said " I checked the voltage at the battery. anywhere above about 700 rpm the voltage was about 15.75V. Around 600, it was about 14V. At 550 rpm it was a little under 13. It was always higher than resting voltage with the engine off."

Do you have an alternator? It seems high, I would expect less than 15 volts.

You did say new coil and condenser but I still vote for an ignition problem. Good luck. Pete

Check your engine ground if you already haven't, you may have an unwanted resistance in the path to the negative battery.  Find a good ground source on the engine (shiny bolt etc) connect jumper, connect to the grounded battery with the jumper.  Just a thought and real easy to check.

Ted, Redding, CA

Greenbird: the resistor I've been running is what was on it when I bought it, possibly original or else quite old. I tried running a 1.20 ohm unit I got from Napa with no change to speak of.



Pete: I'm running a generator. I thought the voltage was high too, but the ford manual says the regulation point is between 14 and 16. At one point the volts went off the scale though, as in more than 16, so I took the regulator off and removed the cover. Everything looked fine. I moved the contacts with my fingers. Not knowing what else to do and having no replacement handy, I reinstalled it, and noticed that now average volts were more like 14-15 than 15-16. Didn't really seem to affect the way it ran.



brokengate, I could stand to recheck that.



So eventually I got exasperated to the point that I wanted to try to drive the car to its normal resting place and take a break from this problem until after the new year. I was able to keep it running in gear with 2-foot driving, wasn't as hard as it had been when I started this thread. It drove very well and I made it all the way to the garage. It was idling in gear at around 600-650 rpm, though not smoothly. When I arrived at my destination I sat in drive and just let it run, waiting for it to stall. It never did, though it started to miss and get unhappy the longer I let it go. I tried to back the idle down a little (maybe an eighth turn of the screw) at this point, which it did not like, and it was much rougher but still running. I then proceeded to turn the mixture screws out bit by bit at the same lower idle. When I hit 2.5 turns out, it dropped into gear and ran smoothly for a little while before getting lumpy and irregular.



I keep the car at a friend's house, and one of his neighbors worked at Ford and teaches auto tech and is generally a bit of a guru. I ran into him when I was making those adjustments and he wants to work on it with me after the new year, so hopefully we'll get this sorted once and for all. I'll keep you posted when I have more info.

1954 Crestline Victoria 312 4-bbl, 3-speed overdrive

I don't recall you mentioning it and you probably have you checked distributor cap, rotor and spark plug wires. You mentioned that the weather was cold. Where I live (Pacific Northwest) all kinds of ignition issues come up in the winter. I helped a friend once because her car was running crappy. We went out at night, opened the hood and sparks were flying all over the engine compartment from rotten spark plug wires. You couldn't see them in the daylight. Anyway good luck. Mark

Mark

1956 Mercury M100
1955 Ford Fairlane Club Sedan
Delta, British Columbia

I spent several hours today working with my neighbor to try to sort this problem out. We quickly confirmed that the idle quality deterioration and stalling was due to spark breaking down. We found that, while idling through the resistor, when the quality started deteriorating, we could "fix" it instantly by connecting a jumper wire to the starter solenoid direct lead to the coil, aka bypassing the resistor. With the jumper connected, idle was great. Disconnected, not so much. So, we attempted to run the car for a bit with the resistor out of circuit, but the points couldn't take it, and after a while of running well, all spark dropped out. Sanding the points would bring it back for a limited time. Voltage drop through the points was unacceptable.



I was pretty sure I had left the ignition on (unintentionally of course) right before this problem cropped up so it seemed I may have burned the points from that and that was all that had ever been wrong. I bought a new set of points and when paired with the new resistor and coil I had already installed, the idle was like butter. Honestly as smooth and steady as one could ever ask for. With the dwell at 27* and mixture screws at 1 1/8 turn out, it would idle in gear under 500 rpm, though it preferred to be around 550. Problem fixed, right? No. Of course not. haha.



I was ready to take it out and stretch its legs at last, but I never got out of the driveway. I packed up all of my tuning stuff and the sun had nearly fully set, so once I started the car again I needed to turn the lights on. Immediately noticed irregularity in the idle with the lights on. I hit the brake (again, no power assist) and it got a little worse. Dropped it in gear, instant stall. I tried a few more times but the only way it would run with an electrical load in gear was if I held my foot in the gas.



So it seems that the electrical problem runs deeper than the ignition components themselves. I will certainly be checking the charging system, but really, with a good battery I would expect it to be able to run for at least a short time with the generator disconnected. I suppose that expectation is ill-founded.

1954 Crestline Victoria 312 4-bbl, 3-speed overdrive

Just a suggestion-have you considered the ignition switch itself possibly being the problem?

  

Only casually. I'm not sure what could be wrong with it that would cause my trouble except perhaps excessive resistance, but that should show up whether the lights are on or not (right?)

1954 Crestline Victoria 312 4-bbl, 3-speed overdrive

One other thought.Is the ground strap(little braided wire) in the distributor actually connected between the breaker plate and the distributor body under the breaker plate?It may appear to be intact but when you check its actually broken from the breaker plate advancing and returning.

  

It's fixed!



My neighbor came over and worked with me again today. The first thing we found was that the misfiring began when the voltage seen on the positive side of the coil dropped below 9. It stalled by 8.5 V every time (8.5 being the spec'd minimum). Turning on the headlights and other electrical loads dropped the voltage more aggressively and killed the car. Naturally, dropping the trans into gear dropped RPMs and voltage, so the spark would stop. At this point I was pretty convinced that the voltage regulator or generator was at fault, especially since I frequently saw charging voltages as high as 16. We tried bypassing the resistor briefly and found that it didn't help improve matters this time.



At this point we somewhat arbitrarily got around to checking the indicated advance when shifted into gear. I was genuinely surprised to find that advance was dropping from about 12 to about 6 before the engine died. I was surprised because I had tried idling way down in the rpms and thought I'd seen the mechanical advance floor already, multiple times. My neighbor didn't like the apparent lack of initial primary spring tension in the distributor and so we pulled the distributor and thoroughly cleaned and lubed all the working parts. In the end we didn't have to alter the spring tension because the cleaning and lube allowed even the very light tension to fully seat the advance mechanism easily.



Upon reassembly, with an initial advance of 12 degrees, the engine would idle without hiccup or misfire down to 375 rpm. Maybe it could have gone lower, but that's as low as we went. I couldn't believe it! It dropped into gear smooth and strong from 700 rpm down to about 525.



I'm still a bit puzzled as to why all of the electrical load problems and spark breakdown went away. It makes sense that the advanced spark made the engine more powerful at a given rpm and thus able to run in gear. I suppose that the timing also required less energy from the ignition system such that the supply voltage drop no longer caused the spark to fail.



So, I believe in the end I was fighting just 2 problems: bad points and a false initial advance reading--both items I thought I'd already ruled out! Go figure. Oh, and the old resistor was no good, so it was worth replacing that as well--tried hooking it back up and the engine ran poorly.



Thanks for all of the help and input! I'm so happy to have this resolved, as the car is very fun to drive.

1954 Crestline Victoria 312 4-bbl, 3-speed overdrive