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Can someone ID this one wire. It goes to the dizzy

Can someone ID this one wire. It goes to the dizzy
Just behind the air filter housing on my 71 Renegade 2 (First day I got it home).

DSCN0818.webp

Mounted next to the coil on my 78, msd coil and ballast resistor (From PO I since bypassed it.)

IMG_14981_zpsa0858cd1.webp
 
That sounds interesting, is that what you have done Lumpy? or Posi, I was refering to that resistor.

No-my '85 had the res. wire in the firewall loom that I removed when I installed a MSD ign.
I just remember see'n a couple of early 70's CJs, and noted the big resistor next to the coil. Really don't know if that was OEM or not.
LG
 
Thanks Posi . I would have thought that thing would be all corroded and rusty.
 
What helps is they have a ceramic body. The connectors, and exposed spring if applicable do get rusty without maintenance.
 
With respect to the rest of the guys...

The idea of the Resistor Wire is to produce 1.35 Ohms to 1.5 Ohms resistance.
The output voltage at the coil doesn't matter.

Voltage (Electrical Pressure) will drop as Amperage (Electrical Volume) drops.

The idea is to knock back the WORK POTENTIAL of the current traveling to the ignition coil.

Remember, that current passes THROUGH the coil,
To the module, where a Transistor has to switch the electrical load 'On-Off' for the ignition to work.

The Factory DuraSpark module has a fairly weak switching transistor,
So the Amperage (Volume) of current needs to be knocked back to keep the module alive.

-----------

You have TWO choices,

1. You can use a ceramic block and common wiring,
OR,
You can use a resistor wire like the factory did.

The ceramic block will fail from time to time,
All the Resistance is being made in a VERY SHORT run of wire wound in that block,
So it overheats and cooks with time.

The Resistance Wire spreads the resistance out over a long run of wire, so no part of that wire gets REALLY hot.

2. You can use common wire to replace the resistor wire,
And use a MODULE SWAP that allows for full current, (No Resistor)
This is pretty easy, it's called a 'Stealth HEI' module swap.

You keep the factory module,
GUT the case, take the circuit board out,
And connect a GM style HEI module designed to work at full current load to the wires.

The 'Stealth HEI' is a full power unit, so the ignition coil will acutally be able to use more of the electrical energy,
Increasing spark energy at the plugs.

GM HEI style modules are available everywhere, so it's not a propritary part, easy to mount/wire, and solves the issues with the Resistor wire you have.
 
Interesting post as usual TeamRush, in this case there seemed to be an overheating of that resistance wire. Can you give some input as to why that would happen? Should that resistance wire be separated from the rest of the system, since it does get hot?
 
Not in my OPINION.

Resistance wires build heat, it's a fact of life.
All resistors do...

Think 'Duty Cycle'...
When the engine is running, the circuit is only active about 50% of the time, since the module has the circuit 'Open' the other 50% of the time.

This is a 50% duty cycle.

When you leave the key switch in the 'Run' position WITHOUT the engine running,
The resistor is seeing a 100% duty cycle.
That's a TON more heat to deal with.

In my OPINION,
The resistor wire shown has been left 'ON' and cooked itself at one time or another,
And the heat cooked the insulation which fell apart over time.

The 'Rubberized' insulation on both Fusible Links and Resistor Wires is designed to take the heat from NORMAL use,
But that same insulation is susceptible to overheating,
And to UV light, Engine vapors (Fuel, Oil, Ect.) over time.

The 'Quick Fix' would be a ceramic 'Pot' resistor and common wire.
The biggest problem I have with these is when they get hot, and get moisture on them, they corrode like crazy, or they come apart from thermal shock.

The ones that have a 'Paste' looking stuff covering the actual resistor wire winding hold up longer in wet conditions,
While the 'Open' versions handle the heat better since they can shed that heat into atmosphere.

Everything is a trade off...

I don't mind the ceramic resistors, they usually last a few years and they are available about everywhere, so it's not a proprietary part you would have to special order.
 
So somebody left the key on burning that wire and the best solution would be to just replace it and of course it is a crimped on connection because the resistor wire cannot be soldered.
 
Mine was crimp'd and soldered.
LG
 
Is there any negative effect to going with the stealth HEI? Is there any benefit other than getting rid of the resistor?
 
Is there any negative effect to going with the stealth HEI? Is there any benefit other than getting rid of the resistor?

The 'DuraSpark' clone module replacements all come from 'China' now, and they simply aren't reliable unless you have a LARGE resistor in place,
Then sometimes they aren't reliable...

They are also getting expensive with no improvements to things like the weak switching transistor.

--------

The 'Stealth HEI' swap gives you RELIABILITY,
HEI modules DO NOT heat up when the key is left in the 'RUN' position nearly as bad as the DuraSpark/clones modules do.

It's your choice to remove the resistor wire or not.
The resistor wire left in place WILL NOT harm the HEI style module,
Removing it will increase spark energy a little bit.

The HEI style module was designed to work with an E-core coil,
Where an E-core coil on the DuraSpark style module will often cook the module.

The E-core coil has LESS RESISTANCE than the factory canister coil, so the module gets hotter working with the E-core coil.

Removing the resistor wire and using common wire,
And using an E-core coil will substantially increase spark energy to the spark plugs.
(Assuming you have a good cap, rotor, plug wires, engine 'Ground Path')

With these MARGINAL, single coil ignitions trying to fire all cylinders,
Any increase you can show COST EFFECTIVELY, will help you get the fire lit in the cylinder CORRECTLY.

Just getting the cylinder to 'Spark' DOES NOT ensure an ignition or good flame front across the cylinder,
But the 'Hotter' and Longer Duration the spark is, the better chance you have of getting the cylinder lit properly...

The module swap is about $25,
The resistor wire removal costs the piece of wire and some connectors,
The 'E-core' coil runs about $5-$10 in the salvage yards,
Both GM Remotely Mounted, and Ford Remotely Mounted E-core coils will work, so there is no shortage of them,
And E-core coils RARELY go bad,

So instead of paying $65 for a 'New' discount store coil,
$5 or $10 at the junk yard for the coil, connector and bracket seems like a pretty good deal to me.

Again, NON-Proprietary parts, all off the shelf,
And if the coil were to fail, E-core or Canister coils will work to get you home.

The module is Non-Proprietary, still easily available in any parts store in the country, and hundreds in any salvage yard for your 'Spares'...
 
I can attest to the china modules. I purchased a china BW figuring it would be the best of the china stuff. Both side clips broke when I joined the connectors, and the new out of the box module didn't work. It went back to the parts store.
 
As I said, I've done TR's swap (all but the hei) which includes cap, rotor, wires, e-coil, and it is night and day over stock. Better start, better response, better mileage, better everything. I actually lost my stock coil on the trail and did this conversion in the woods since I had recently picked up the parts and they were in the back. Took about 15 minutes, true story. I'm still running the stock module, it's the best one O'Reilly has, no idea who makes it but it visually "beefier" looking with larger ribs for cooling. I haven't had any issues with it. About 2 years old. I'm not running a resistor wire or resistor.


Wooly
 
Wooly, '78 up have the resistor wire in the harness, you won't know it's there unless you test for it,
Or tear the harness apart looking for it...

Personally, I wheel alone much of the time.
I have a distributor with TWO pickup coils (Triggers),
I have TWO modules,
I have TWO coils.

I can switch back and forth from #1 Ignition to #2 Ignition with a flip of a dash switch.

Redundancy is a wonderful thing!
Since it's RARELY the cap/coil/plug wires that give up,
Especially if you used high quality to begin with,
I'm covered,
And since EVERYTHING is mounted under the hood,
No 'Spares' rattling around in the cab/tool/glove box...

There is no sense in having 'Spares' rattling around if you can mount them and get some good out of them...

----------

In the beginning, there was a RAGING WAR about which module would do best,
DuraSpark (or clone), HEI (or clone), and a CDI like MSD 6 modules.
I installed a second pickup (Trigger) in the distributor so I could switch from one to the other, both modules side by side, for testing...

When the testing was over,
I off-set one trigger about 8° RETARDED,
Now I have one trigger for light weight running, maximum economy,
And a second retarded about 8° (currently) so when I pull the trailer, or go lugging up big hills with heavy loads I can retard the ignition to keep the engine from pinging or heisting.

It's a poor mans 'Towing' package for the little circa '73 AMC engine...
And it's a redundant back up to the primary ignition in the even a trigger, coil, module fails...
Also makes a pretty good anti-theft device when the switch is in the 'Off' position.

I'm NOT trying to sell this as a home game, just saying it's pretty easy if you have basic skills with wiring and some mechanical ability.
Nothing but hand tools required to do this.
 
'Stealth HEI' module swap:79/360

To clarify, if you were to use an epoxy filled canister coil, and stock resister wire there wouldn't be a need for the diode?
If your running an ford e-core the diode stays and stock resistor wire goes?

Edit: I would think the diode is needed in both situations to keep the current flowing in one direction.
 
Last edited:
'Stealth HEI' module swap:79/360

To clarify, if you were to use an epoxy filled canister coil, and stock resister wire there wouldn't be a need for the diode?
If your running an ford e-core the diode stays and stock resistor wire goes?

Edit: I would think the diode is needed in both situations to keep the current flowing in one direction.

A diode isn't needed in an ignition circuit.

The 'Excite' wire for the Alternator comes off the ignition circuit,
So the 'Excite' circuit shuts off when the engine isn't running.
The 'Excite' wire is a RESISTOR wire ALSO, 10 to 15 Ohms, (The small 'Brown' wire is a resistor wire),

A diode will REPLACE the resistor wire, so you can use common wire.

In the Alternator circuit, the HIGH RESISTNACE (10 to 15 Ohms) is there to keep the 'Excite' wire from BACK FEEDING the ignition.

The way the voltage regulator/Excite circuit works in the alternator...
The 'Excite' terminal is a 'Ground' when the alternator is NOT charging, since the regulator is drawing current and sending it to the rotor to start the charging process.

As soon as the alternator starts to charge,
The 'Excite' terminal becomes 'Positive',
It changes polarity...

The Positive feed in the 'Excite' wire will back feed through the ignition system,
And that will power the ignition when you turn the key switch off.

The Alternator 'Excite' Resistor Wire (10-15 Ohms) is enough to keep the 'Positive' from back feeding the ignition with enough energy to keep the ignition working.
(What electrical folks call a 'Sneak Circuit')

A 'Diode' is a one way gate valve for electricity.
It allows current to flow ONE direction only,
So the 'Excite' circuit can be powered GOING TO the alternator,
But the alternator CAN NOT back feed the ignition.

-------------

When a Diode is used in the 'Stealth HEI' swap,
It's used with a COMBINATION IGNITION SWITCH.

Jeep used TWO different ignition switches,
One was COMBINED, Start/Run combined when starting the engine,
Then falls back to the 'Run' circuit when you release the key switch...

The other used a SPLIT switch, Start & Run are separated all the time.

*IF*...
You get the starter relay 'Running On' after you start the engine, then you need a diode.

Since those switches haven't been used since the early '80s, and the replacements don't have the internal connection, not many will need the diode,
But I include it in the diagrams anyway, so folks know how/where to solve the problem when it presents.
 
:biggun: "Holly Cow, that was Intense!" :biggun:

Thanks for the info TR! :rock:
 
Just a heads up, Radio Shack will be out of business by the end of the month. I've been by a couple times to pick up a few electrical tools and supplies while they last, 60-70% off.
 
Wooly, '78 up have the resistor wire in the harness, you won't know it's there unless you test for it,
Or tear the harness apart looking for it...

Personally, I wheel alone much of the time.
I have a distributor with TWO pickup coils (Triggers),
I have TWO modules,
I have TWO coils.

I can switch back and forth from #1 Ignition to #2 Ignition with a flip of a dash switch.

Redundancy is a wonderful thing!
Since it's RARELY the cap/coil/plug wires that give up,
Especially if you used high quality to begin with,
I'm covered,
And since EVERYTHING is mounted under the hood,
No 'Spares' rattling around in the cab/tool/glove box...

There is no sense in having 'Spares' rattling around if you can mount them and get some good out of them...

----------

In the beginning, there was a RAGING WAR about which module would do best,
DuraSpark (or clone), HEI (or clone), and a CDI like MSD 6 modules.
I installed a second pickup (Trigger) in the distributor so I could switch from one to the other, both modules side by side, for testing...

When the testing was over,
I off-set one trigger about 8° RETARDED,
Now I have one trigger for light weight running, maximum economy,
And a second retarded about 8° (currently) so when I pull the trailer, or go lugging up big hills with heavy loads I can retard the ignition to keep the engine from pinging or heisting.

It's a poor mans 'Towing' package for the little circa '73 AMC engine...
And it's a redundant back up to the primary ignition in the even a trigger, coil, module fails...
Also makes a pretty good anti-theft device when the switch is in the 'Off' position.

I'm NOT trying to sell this as a home game, just saying it's pretty easy if you have basic skills with wiring and some mechanical ability.
Nothing but hand tools required to do this.


Thanks TR. I have tested per your info in another thread. No resistor. I'm not indicating that the stock module will take full 12v, just that mines held up so far. I plan to try HEI stealth when/if it does. I think the one I have is BDS. Here is a photo.
ba2191fac76ee22da263d167c8044278.jpg



Wooly
 

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