Dying at idle?!?

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Well, now you HAD to find SOMETHING with the electrical system to go from not cranking to running fine. If you did not, then there is a gremlin waiting to show again.
 
So now the car won't crank. It acted as if it wanted too.

My readings with my multimeter are as follows.

New battery 11.4
Ballast 9.8 and 6.2
Starter 11.2
Alternator 12

The coil was at 5.6 so I replaced it and it read the same.

Now it just barely groans.

What should the voltage be at the switch wire?

I tried jumping at the starter but it just cranked didn't fire and made a couple sparks with the screwdriver.
 
Pull the dipstick out. Smell it. If it smells like gas take all the sparkplugs out. Disconnect one connector from the ballast resistor to prevent ignition, and crank it. Be prepared for gasoline to come shooting out of some or all of the cylinders.
Charge the battery. You are looking for more than 12.5 volts
 
look at your accelorator pumps adjustments, pickup the idle a little bit , set fuel mixture
 
Pulled the cable from the distributor and tested. I have spark going to the coil.
Cranks when I jump it. Starts and sputters when I let key go.
 
You can charge it all day long and if it is bad, it won't take a charge. What is the voltage across the battery terminals after an overnight charge and also after having removed the charger for an hour? You CAN get bad batteries out of the store. (I got 2 in a row form the same store once.) The symptom of cranking when you jump it sure points to a bad battery.

Your readings below look fairly good at the ballast output. Of course, the battery voltage is low and the alternator voltage does not make sense.... unless it was running. Was it running or cranking or was the key in RUN but not running when you took these readings? If running, then the charging circuit likely has problems.

New battery 11.4
Ballast 9.8 and 6.2
Starter 11.2
Alternator 12

"Starts and sputters when I let key go. " Does this mean it does not fire at all when cranking but then fires for a few rounds when you let the key go from START to RUN? Or does it mean it starts while cranking but then dies when you let the key go to RUN? Being clear here may tell us a lot.
 
Measure the voltage drop from the big stud on the starter to the case of the starter. You need 8 V or higher while trying to crank. If not, find the main voltage drop. If true, then the starter is at fault or the engine has excessive resistance (try turning over by hand). One drop that people miss is from starter case, thru block, thru return cable to BATT-. Aluminum can give high resistance w/ a little oxidation. It does sound like your battery is bad. Autozone and others will test it free in the parking lot. I have found many bad batteries lately, and 2 were only 4 months old. The wouldn't "hold a charge".
 
once you get the electrical figured out...sounds like your carbs are leaking gas into the manifold, I may be wrong but, weber carbs may like less fuel pressure than the factory setup....
 
"starts while cranking" lets go of key on position and shuts off.... doesn't that sound like vapor lock? same problem i had.

i ended up replacing a lot of things... what did the job i think was replacing the ICM, reluctor and pick up coil. careful where your gas lines are running through.
 
abody said:
once you get the electrical figured out...sounds like your carbs are leaking gas into the manifold, I may be wrong but, weber carbs may like less fuel pressure than the factory setup....
Click to expand...

I have a fuel management system from redline keeps the fuel at 3 psi
 
BIG-B-Barracuda said:
"starts while cranking" lets go of key on position and shuts off.... doesn't that sound like vapor lock? same problem i had.

i ended up replacing a lot of things... what did the job i think was replacing the ICM, reluctor and pick up coil. careful where your gas lines are running through.
Click to expand...

Thanks I am installing pertronix igniter today. And if not then this is what it's gotta be.

Any tips or tricks are always appreciated.
 
****** apart of course from me moving my gas lines away from heat source and getting a new carb. Base plate that doesn't generate as much heat ....

has been spot on so far.
 
So after many parts and curse words and testing. I upgraded to electronic ignition and jumped the battery and she's back!! Now I'm getting proper reading at the battery and alternator.
Just need to drive it around and get the battery charged again.

Thanks to all of you for the help.
Couldn't have done it without you Fabo!!!!
 
BIG-B-Barracuda said:
"starts while cranking" lets go of key on position and shuts off.... doesn't that sound like vapor lock? same problem i had.

i ended up replacing a lot of things... what did the job i think was replacing the ICM, reluctor and pick up coil. careful where your gas lines are running through.
Click to expand...

Sounds like a classic bad ballast resistor to me.
 
no way.... sometimes it is yes i agree but most are not this easy.

mine wasnt anyways,

and after many new parts and upgraded ignition it started just fine. . . not really knowing what the culprit was.
 
BIG-B-Barracuda said:
no way.... sometimes it is yes i agree but most are not this easy.

mine wasnt anyways,

and after many new parts and upgraded ignition it started just fine. . . not really knowing what the culprit was.
Click to expand...

Well I put the original ballast back on because the new one had one terminal break.

I think it was the points. Super weak spark. It had a weak charge on the battery so I jumped it and let it run for about 25 minutes. Turned it off and back on with no problems.

I'm getting all the proper readings on my multimeter now so I think it was the distributor issue.

Now I just gotta drive her around and see how it all goes.
 
BIG-B-Barracuda said:
no way.... sometimes it is yes i agree but most are not this easy.
mine wasnt anyways, and after many new parts and upgraded ignition it started just fine. . . not really knowing what the culprit was.
Click to expand...
Actually yes, the "fires while cranking but dies when key is released to RUN" is exactly what will happen with an open ballast resistor. That was why the question was asked. It is possible that the points could cause this, but it would not normally have started easily or at all. Simply adjusting them is the first step if they are suspected. Condenser bad? Possibly...

The typical symptom of vapor lock is that you stop after driving and the engine compartment is good and hot, and wait a few minutes and then the car will not fire at all, just sputters occasionally while cranking and cranking.

BTW, the OP's year of Mopar (1972) would not have points in stock form. Guess we need to ask about ALL possibilities.
 
Get the heat out of/away from the fuel lines and the fuel. Re-route the fuel lines, cover them with reflective tape or shielding, and so forth. I have not had to do this, but on some /6's routing the fuel line over the top of the valve cover instead of up the front of the engine is helpful. (May get in the way of valve cover access though.)

Helping the carb stay cooler can help too, with a thicker base gasket to help insulate it. (That would be fuel boiling out of the carb, not vapor lock strictly speaking.) Make sure the exhaust manifold heat riser is not stuck open, which will heat up the intake even more.

And if you can get fuel without ethanol in it, than can help a bit too.
 
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