i have a 64 mustang and i had to rewire it and i have it just about done and i ran into this issue. it may be a normal issue but i do not like it.

this is what i have going on if your familiar with the older cars when you turn the key to run the dash lights for the oil and the gen light up. when the oil pressures is made that turns that light off. the same with the gen the gen powers form the A on the regulator and just as soon as the gen put out voltage that cancels the 12 volts it was getting from the A on the reg. anyway the car has a resistor wire in that circuit i do not quite understand that purpose but the new wire kit uses a resistor that crosses from the A wire and the coil wire that the light connects to. but if i leave the key in run and the engine is not running so the gen make power that resistor gets hot. today i started the car for the first time after the new wiring with the cluster setting on a table and the cluster wires i let long for that test. the resistor got so hot it started to let out the smoke. and we all no electrics all run on smoke.

so what i'm thinking about is using a relay under the hood with the coil connected to both the A on the reg and the other side to the coil on the engine just like the bulb would be. then power the bulb from a b+ and ground so when the N/O contacts close because the key provided power just like it would for the bulb and then the bulb would light up. but what i need to find out if there is a relay that will not burn out with it gets just a bit of power like if the engine was idling and the gen was making say 1 volt positive or discharging 1 volt so that the power would backfeed like it does when the key is on and the gen is not making power. if you understand what i trying to do here?

what i do not need is the resistor getting hot and burning out or causing a fire. the car had a resistor wire in the loom and when i took that out i noticed all the wires inside that loom had the insulation burned off and bare wires. so i think that resistor wire was getting so hot it was melting the other wires insulation.

so if i can find a relay that will actuate with a small amount of power and not burn out i will just install one. i do not know how much volts it takes to make the A on the reg to cycle but that relay never seems to burn out so it may be that any 12 volt regulator will work so maybe you guys can help me confirm that.

thanks

 

In a 64 Mustang there was a resistance wire used in place of an actual ballast resistor, to drop the voltage for the ignition coil.
Unfortunately many fools did not realize that and so tried to power other things from that same ignition coil feed. The result was problems and sometimes that wire failed and the car would not run.
So the solution is to only feed the ignition coil from that resistance wire. Then heat will not be a problem.

 

ok then that is what that resistor wire i found was for. i was wondering. it now has a ballast resistor. so maybe i do not even need that resistor in the gen circuit at all then the comet wire print and the mustang pring does now show a resistor wire they show a wire from the A on the reg to the bult and to the coil terminal on the ign. but when i have that setup the resistor smoked/

 

ok then that is what that resistor wire i found was for. i was wondering. it now has a ballast resistor. so maybe i do not even need that resistor in the gen circuit at all then the comet wire print and the mustang pring does now show a resistor wire they show a wire from the A on the reg to the bult and to the coil terminal on the ign. but when i have that setup the resistor smoked/

Usually the ballast resistor is bypassed when the engine is cranking, to compensate for the battery voltage being reduced due to the starter motor current draw. I am not sure exactly how that is done, I never had to deal with it.

 

yes i know that. what i did was that that resister the was on the gen light by itself. it was not in the ign. circuit. that resistor was not in any prints for cars using generators so i have no clue. unless it was intended for the alt. circuit and the owner of the car installed it without knowing it was not needed for generators. but i also left it there. so today i took another bulb and socket and placed it in the cluster and turned on the key the light came on and then started the engine the light when off. i did that a number of time's and it worked as it should have. then i disconnected the coil and cranked it a number of times to get the light to go on and off and it works. so i sent a email to the painfull wire company and asked them why they have that resistor in the circuit. they might come back and tell me that is for the alt system.

 

As @MisterBill2 said, that ballast resistor should ONLY be connected to the coil. He also stated, and you acknowledged that you know this fact, the ballast resistor is bypassed during startup. Beyond that it has no function other than to prevent the ignition coil from burning up. Without the resistor (or original resistance wire) the coil will burn and fail. I've taken coils apart before that had the resistor bypassed or the car was hot-wired. If you're burning up the resistor then you have a wiring error. And I can say that for sure because under normal conditions it will get warm, even hot, but not so hot that it leaks magic smoke.

 

you guys are missing the point! i'm not talking about the coil resistor i was talking about the resistor the wire kit has at the generator dash light in the dash panel. that resistor got hot and smoked. i have since found out that it is not required in that circuit. but if it was i was asking about the relay pull down current if a relay could be used in the gen circuit.

anyway it is done and over thanks

 

How about some pictures? The last generator I messed with OUTSIDE of a car was a Toyota 60 amp alternator with three wires. One wire was used as a ground for the generator dash light. If there was power on it the dash light would have 12 volts on both legs and would not light. But if the alternator was not spinning or producing then the dash light warning light would illuminate. There was no resistor involved, nor was there any ballast resistors or resistance wire. So I'm at a loss to understand exactly what's going on with your car. The only problem I can see thus far is that it's a Ford. Had always been a Chevy guy but of late I'm a Toyota fan.

 

thanks the generator is done. i got the local generator repair shop to give me the anwser. i just hooked the gen light up on side to the A on the regulator and the other side the to coil at the ign switch and it is working good. i think that resistor was for an alt, system. this wire kit he got was a generic kit and it did not have any mention in it for a generator. so that is done thanks everyone

 

Sorry, I thought we were talking about the ignition.

ballast resistor, to drop the voltage for the ignition coil.

This is where I got off track.

So was it a wiring error? Can't see it working now after it wasn't working, unless you changed something.

 

yes i think what that kit was really for was the 65 mustang that had the alt. in it and that resistor was for exciting the one wire alt system. the manual for this kit did not mention anything on the generator. but yes it is all good. i found the temp sensor was bad and that is why the temp gage went to hot fast. i did the temp wire to ground test after i remembered that test and the temp gage reacted the same.
thanks