Ballist resistor overheating

Posted By: cudarroger

Ballist resistor overheating - 02/05/12 10:51 PM

I am lost on this one. 70 aar factory 340 dual points. The car will start and idle fine and the ballist resistor heats up and the ignition starts breaking up and the car dies and burns out the condenser. Is there back feed from somewhere? All suggestions are appreciated.

Posted By: DAYCLONA

Re: Ballist resistor overheating - 02/06/12 12:18 AM

Quote:

I am lost on this one. 70 aar factory 340 dual points. The car will start and idle fine and the ballist resistor heats up and the ignition starts breaking up and the car dies and burns out the condenser. Is there back feed from somewhere? All suggestions are appreciated.

There are different Ohm rated 2 prong ballast resistors avaliable for Chysler/AMC

Have you confirmed the wiring on the coil, Blue wire off the bulhead (ignition) is positive (+), the distributor/point(s) Black, is (-) negitive on the coil, a 2 prong ballast has no terminal specification

Posted By: RapidRobert

Re: Ballist resistor overheating - 02/06/12 12:18 AM

I could see w the ign left "on" that current could burn out the ballast but I'd sure think it'd burn the points first tho w both sets closed they would be passing 1/2 the amount I'd think (parallel circuit). Lets solve the breaking up that's making it die. More info/details please. Correct ohm ballast I'm assuming

Posted By: cudarroger

Re: Ballist resistor overheating - 02/06/12 04:39 AM

I did not know that there are to different ohm resistance. What are the two different ratings?

Posted By: RapidRobert

Re: Ballist resistor overheating - 02/06/12 04:43 AM

1.25 ohm ballast w the orange/chrome box. .25 ohm w the gold box. Those are nominal ratings, actual vary widely & OE 2 terminal ballast vary widely also. We're missing something here

Posted By: dynorad

Re: Ballist resistor overheating - 02/06/12 05:07 AM

Need to know coil resistance as well. The current in the primary ignition circuit is determined by the sum of the ballast and coil resistances.
Also need to ensure that you don't have an overcharging condition so your voltage is too high thus burning things up.

Posted By: DAYCLONA

Re: Ballist resistor overheating - 02/06/12 07:33 AM

Quote:

I did not know that there are to different ohm resistance. What are the two different ratings?

Would be great if you "spill the beans" on what parts your running, any mods you've performed, etc, etc, rather than assume you have factory parts or the proper aftermarket parts

Posted By: 451Mopar

Re: Ballist resistor overheating - 02/06/12 08:07 AM

Quote:

I am lost on this one. 70 aar factory 340 dual points. The car will start and idle fine and the ballist resistor heats up and the ignition starts breaking up and the car dies and burns out the condenser. Is there back feed from somewhere? All suggestions are appreciated.

How is the condenser burnt out? Is it shorting out? That would make the ballast run hot.

Posted By: cudarroger

Re: Ballist resistor overheating - 02/06/12 03:27 PM

I'm running all stock componets. Coil, ballast, V.R., Factory distributer,dual points and condenser, Plumcrazy Garage restored alternator. Was there ever a ground strap on an E-body from the engine to the firewall? I don't remember one being there. How would the condenser be shorting out?

Posted By: dynorad

Re: Ballist resistor overheating - 02/07/12 10:38 PM

Have you shorted out more than one condenser? The condenser is a big capacitor. It does not have DC current passing through it unless it is shorted. Unless it shorted out from old age the only way to short them is to have too much voltage across it, as far as I know.

Posted By: phantomx

Re: Ballist resistor overheating - 02/08/12 03:01 AM

I have had condensers fail from the new clamp crushing it. As a rule, I always reuse the old clamp on new condensers to avoid this.
Travis..