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Engine stays running only if the key is held in the start position ....

Cranky

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As soon as you release the key to the run position it dies. Didn't someone just post about that happening recently? If there was, I can't find it now. Anyways, did a lot of work on this car a little over a year ago but it was all mechanical and no electrical as I'm shade blind and faded wires only make it worse for me. The car also has no ballast resistor in the system and still has a point system on it. The car came for a carb issue but the carb seems to be decent idling and revving up even right after firing it up cold. Yeah, I hot wired it.

I replaced the ignition switch with a known good one that I had stuffed away and the car does the same thing. Dies when you release the key. The under hood wiring on this thing SUCKS!! It even has house type wire nuts on it. Told him he needs to buy a new under hood harness as this one is junk (dried and hard as rocks) but he wants to get it running as is for now. He did say it's been running fine until recently. The points don't seem to be fried because I just started it and ran fine....and the battery is only 12.3v.....

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That IS the issue.. run goes through the ballast. If you don't have one jumper the wires and I bet it keeps running. Just don't leave it that way...
 
That IS the issue.. run goes through the ballast. If you don't have one jumper the wires and I bet it keeps running. Just don't leave it that way...
He says it was running fine like that and then it started having a low speed miss and then it wouldn't start up and stay running anymore. He was going to bring it to me for what he thought were carb issues and that's when it wouldn't stay running. I only jumped it to see how the carb was acting but it seemed fine sitting here but haven't run it on the road.....just sitting and didn't do that for more than a couple of minutes.
 
So the wiring from the run position, that should be going through the single ballast for the points distributor, has fell off or burned off somewhere..
 
I don't get how it was running before....since there is no ballast resistor on the car at all! When I was working on it the last year or so ago doing the front end etc, it ran fine but never paid any attention to it having one or not but it had a different carb. He said he replaced the carb because it started leaking. Well, what can I say. He knows construction and not cars. Electrical systems is my achilles heel.
 
FRIED points at the least! C'mon Crank, get back in the groove.Probably some bad wiring also.
 
I'd trace the output from the ignition switch.
With the ballast disconnected (and not jumped) the "start" side should have battery voltage only in the "start" position and nothing in "run". The "run" position should have battery voltage only in the "run" position and nothing in "start".
The ballast doesn't "have" to be there for an engine to run if the "run" and "start" circuits have been jumped. The ballast reduces voltage put to the stock coil when in "run".
How an "internal ballast" coil affects this I'm not really familiar with.

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Running with the ballast resistor bypassed will eventually burn up the coil. Maybe try a different coil?
 
I bought a 64 Plymouth with that same problem. I found that there were two light brown wires . One was power only when the ign switch was putting power to the starter, and the other was 12 volts all the time. The wrong one was hooked up to the ballast or coil. ................................MO
 
He says it was running fine like that and then it started having a low speed miss and then it wouldn't start up and stay running anymore. He was going to bring it to me for what he thought were carb issues and that's when it wouldn't stay running. I only jumped it to see how the carb was acting but it seemed fine sitting here but haven't run it on the road.....just sitting and didn't do that for more than a couple of minutes.
If you turn on the ignition do you have voltage at the coil?
 
I don't get how it was running before....since there is no ballast resistor on the car at all! When I was working on it the last year or so ago doing the front end etc, it ran fine but never paid any attention to it having one or not but it had a different carb. He said he replaced the carb because it started leaking. Well, what can I say. He knows construction and not cars. Electrical systems is my achilles heel.
Well the engine will run without the ballast it's there to drop the primary voltage to the distributer so the points last longer and don't burn up. I would turn the ignition on and check for 12 volts at the positive side of the coil (I suspect you wont have it) then trace the wires back to the ignition switch
 
I'd trace the output from the ignition switch.
With the ballast disconnected (and not jumped) the "start" side should have battery voltage only in the "start" position and nothing in "run". The "run" position should have battery voltage only in the "run" position and nothing in "start".
The ballast doesn't "have" to be there for an engine to run if the "run" and "start" circuits have been jumped. The ballast reduces voltage put to the stock coil when in "run".
How an "internal ballast" coil affects this I'm not really familiar with.

View attachment 1010382
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How is a ballast resistor checked? Can you run battery voltage on one side and it will be less on the other side? I've checked 3 of them and none shows a voltage drop.....
 
How is a ballast resistor checked? Can you run battery voltage on one side and it will be less on the other side? I've checked 3 of them and none shows a voltage drop.....
The ballast resister when cold will show battery voltage. When it heats up and then the voltage will drop. It should drop to between 6 and 9 volts
 
How is a ballast resistor checked? Can you run battery voltage on one side and it will be less on the other side? I've checked 3 of them and none shows a voltage drop.....
Take an ohm meter or a multimeter set to ohms, you should get 1.8 to 5 ohms of resistance.
 
The ballast resister when cold will show battery voltage. When it heats up and then the voltage will drop. It should drop to between 6 and 9 volts
So if I leave it hooked up to my voltage tester, the volts will slowly drop?
 
Take an ohm meter or a multimeter set to ohms, you should get 1.8 to 5 ohms of resistance.
Probably will be a lower value than that even. I believe .7 - .8 ohm is a popular .
 
I guess I need a digital VOM to see exactly what's going on since my 55 year old analog VOM isn't showing much but it does show a difference lol
 
I guess I need a digital VOM to see exactly what's going on since my 55 year old analog VOM isn't showing much but it does show a difference lol
Lol, Crank don't worry about it! You're just getting older. Happens to all of us.
 
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