Ignition wiring to coil + with 4G alternator. Burned the resistor wire. Help.

[DirtDonk]

Did you mention which distributor you were running? I think you did but from my phone I don’t see it.

 

[gr8scott]

This is the distributor he bought Paul.

https://www.amazon.com/dp/B00VVAJ9OG/?tag=classicbroncos-20

 

[gr8scott]

@rory007 can you post a link to the wire harness you bought?

 

[m_m70]

http://www.mksportscars.com/media/downloadable/21-circuit-manual.pdf

This is the link rory posted above.......

 

[m_m70]

So did your wiring kit come with a new ignition switch or are you supposed to use your original??
In the instructions it's showing a "ignition switch conversion".

I'm curious how your harness ties into the ignition switch currently.

 

[rory007]

Which wires from the harness are connected to the ignition switch? You have described the original wire harness left remaining on the ignition switch connector. But they must connect to the new harness somewhere or you will not have any key-on power.

power is coming from the battery + red wire connecting to the yellow on the ignition switch.

It sounds, as if initially, you were considering the ignition switch as a completely separate component from the new harness, and connecting the switch directly to other components.
You’re actually supposed to be connecting new harness wires to the switch, so they can control.

kind of. i realized i needed to integrate the ignition switch into the new harness. some of the wiring didnt make a whole lot of sense. the harness has a pink wire labeled coil that connects to the IG switch and then goes to the front of the vehicle. the harness instructions show this to be connected to the coil +. now that i have added the pertronix, it's instructions show only the black with white wire to be connected to the coil +. I have since disconnected the pink wire from the coil +.

the pertronix instructions had the red wire going to the IG switch for 12 volts. i have now connected the red to where the pink was previously connected at the IG switch (green/red-12 vols on).

Probably so. But it also still has to excite the alternator.

also, just for clarification, the harness came with a white wire labeled alternator excitor. this wire i have connected to the alternator, so i think the alternator is good from that perspective.

You could, of course, eliminate any concern about this by adding a relay.
The green wire controls the relay’s on and off function, while larger wires from the battery to the relay to the ignition, do all the rest.
We may have to get deeper into that if you’re not comfortable with relays and their function.

completely comfortable with using a relay if needed.

i have inserted a test light between the coil and the distributor. when turning the key to start, the fuel pump winds up, the starter engages and turns the motor over, but there is no spark coming off the coil. no light on the tester at the coil.

So did your wiring kit come with a new ignition switch or are you supposed to use your original??
In the instructions it's showing a "ignition switch conversion".

i'm using the IG switch from a 75 bronco.

IGN SW PWR -Yellow to red in harness
IGN SW IGN -green/red to pink in harness (on harness side this goes to the pertronix red)
IGN SW ACC-green/black to orange in harness to panel
IGN SW START-purple to purple in harness to starter solenoid


i have tested the wires coming off the ignition switch. The green/red that was (alternator excitor) has 12 Volts when key is "on" position. The pink-brownish wire also has 12 volts with key to "on" position.

im wondering if i could have fried the pertronix box with my previous wire set up. maybe that is why there is no spark coming off the coil?

 

[DirtDonk]

It’s very possible. But let’s not go there just yet!
Hopefully you don’t have to deal with that aspect.

Is the distributor connected to the pertronix box correctly with the two wires mentioned in the diagram? That would be orange and purple I think? Or was it green and purple? I don’t remember.
Does your distributor have color matched wires, or are they all black like I have seen on some distributors lately?

What you have basically is a Ford Duraspark clone distributor, which normally goes into the ignition module or ignition control module, and that does all the work that the pertronics box will now be doing.
In theory, the Pertronix is an upgrade with lots of extra functions, but we need to find out if the distributor can trigger the new ignition control module. If we can’t figure out from their instructions, then perhaps a call to them tomorrow is called for.
In theory it should have no trouble doing that so I think you’re OK there.

There is usually a third wire coming from the distributor which is strictly a ground wire.
I would actually connect that to a ground maybe at the same point that you have mounted your Pertronics ignition box.

 

[DirtDonk]

Oh, and in case you didn’t notice, the original green with red alternator wire, and the original pink resistor wire, both come off of the same terminal of the ignition switch.
So they are in effect the same thing, except for the one resistor wire that reduces voltage at its other end.
So you can use the green with red stripe wire (or black in your case) to excite the alternator and to control the ignition switched power to the Pertronix module.
As you noted, it’s only hot with 12 V when the key is in the ON position.
It’s inactive when the key is in the ACC position so that you can work on other systems or simply listen to the radio without draining the battery prematurely or overheating ignition components.

 

[Broncobowsher]

So did your wiring kit come with a new ignition switch or are you supposed to use your original??
In the instructions it's showing a "ignition switch conversion".

View attachment 902624

I'm curious how your harness ties into the ignition switch currently.

In case I missed it...
White wire on the ignition box is left disconnected. It is only used with points ignition. Don't look at the ford ignition module wiring and think it is the same as the Pertronix. The above diagram is for a Duraspark module, not the Pertonix.

One thing you can check is the orange and purple wires off the distributor, if you put a digital meter across those two wires and set it to AC volts, you should get something while cranking the engine. The distributor makes a small AC voltage signal that the ignition box reads. No AC voltage, no spark.

The white wire on the pertronix box, if you tap it to a good ground, should get a spark as you lift it off the ground. I have had an aftermarket ignition box (similer to but not exactly like the Pertronix) where the coil input worked but the magnetic pickup did not.

 

[DirtDonk]

And even though the distributor and it’s parts are new, that doesn’t mean that you can assume they are good.
So, along with the test of the two wires just described above, put the meter into ohms mode and test between the two wires again.
You’re looking for between 400 and 700 ohms.
Anything outside of that is a defective unit.

There are some specifications that say 400 to 800 ohms, but I prefer using 700 as that was cited more often.

 

[rory007]

Is the distributor connected to the pertronix box correctly with the two wires mentioned in the diagram? That would be orange and purple I think? Or was it green and purple? I don’t remember.
Does your distributor have color matched wires, or are they all black like I have seen on some distributors lately?

there are 3 wires coming out of the distributor. they arent colored coded very well. i traced the ground and have attached that one to ground bus. for the other two, i traced the top one in the distributor which i think is the positive and have connected that one to the green wire from the pertronix. the purple wire to the other wire (not the ground wire) from the distributor.

White wire on the ignition box is left disconnected. It is only used with points ignition. Don't look at the ford ignition module wiring and think it is the same as the Pertronix. The above diagram is for a Duraspark module, not the Pertonix.

confirmed. this wire was not connected to anything in my set up.

The white wire on the pertronix box, if you tap it to a good ground, should get a spark as you lift it off the ground. I have had an aftermarket ignition box (similer to but not exactly like the Pertronix) where the coil input worked but the magnetic pickup did not.

i turned the key to "on" and then ran this white wire over the negative battery terminal. it didnt spark, but the fitech fired up and was pressurizing the fuel in the throttle body.

One thing you can check is the orange and purple wires off the distributor, if you put a digital meter across those two wires and set it to AC volts, you should get something while cranking the engine. The distributor makes a small AC voltage signal that the ignition box reads. No AC voltage, no spark.

i connected the two wires from the distributor (not the ground) to the volt meter and turned the key to start. there were zero volts coming through the volt meter.

So, along with the test of the two wires just described above, put the meter into ohms mode and test between the two wires again.
You’re looking for between 400 and 700 ohms.

i connected the two distributor wires to the volt meter and selected ohms. at the 2k setting, it read 0.567 ohms

 

[gr8scott]

Did you go through the programming sequence per the manual? It needs to be set to Falling Edge (Duraspark). It comes programmed to Rising Edge (points, electronic ignition).

 

[gr8scott]

I used to run the HP-510 and yes, Duraspark will trigger it. But it needs to be programmed to do so.

 

[rory007]

I used to run the HP-510 and yes, Duraspark will trigger it. But it needs to be programmed to do so.

i checked the setup on the pertronix box and it was set up correctly to the falling edge for the duraspark. pertronix seemed to respond well to checking of the programming, so i dont think i fired it. a little good news.

One thing you can check is the orange and purple wires off the distributor, if you put a digital meter across those two wires and set it to AC volts, you should get something while cranking the engine. The distributor makes a small AC voltage signal that the ignition box reads. No AC voltage, no spark.

i didnt get any volt reading on the multimeter when i tried this. i did get .567 ohms when i tested them for resistance.

could the distributor have an issue as it wasnt producing any volts?

 

[Broncobowsher]

I just want to double check, you are on AC volts on the meter, not DC. DC will (or should anyway) read 0.
You are checking while the distributor is spinning. It will be 0 if not moving. It is an AC generator, only making that AC power when energy is put into spinning the shaft.
Before condemming the distributor, check if there is a star reluctor wheel on the shaft passing by the pickup coil. If that is missing it would explain why the ohm reading is correct but there is no signal when the shaft is spinning.

Random photo stolen off the internet showing the 8-tooth reluctor on the shaft.

 

[Oldtimer]

And as I remember there is a gap setting between the reluctor wheel and the coil. I think that is why I have a set of brass feeler gages.

 

[rory007]

I just want to double check, you are on AC volts on the meter, not DC. DC will (or should anyway) read 0.
You are checking while the distributor is spinning. It will be 0 if not moving. It is an AC generator, only making that AC power when energy is put into spinning the shaft.
Before condemming the distributor, check if there is a star reluctor wheel on the shaft passing by the pickup coil. If that is missing it would explain why the ohm reading is correct but there is no signal when the shaft is spinning.

ok. i made sure the reluctor wheel was in the distributor. i also confirmed it was spinning when the engine rolled over. i re-checked the multi meter to the distributor and it did show a small amount of voltage 0.055 when i turned the key to start. i think when i tested it before i didnt have the multimeter on a low enough setting with the decimal point all the way to the left.

i replaced the coil wire going from the coil to the top of the distributor. still no spark.

maybe the pertronix did get fried? if the distributor is giving it the little signal voltage and it isnt waking up, not sure what else it could be.

 

[m_m70]

what wire do you have connected to the small red wire at the pertronix module???

 

[rory007]

i have the green red wire that has 12volts when the key is switched to "on". i have verified the voltage with a multi meter when key is turned "on".

 

[m_m70]

do you have 12v at the coil with the key on?