Installing mopar Electronic distributor

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johnnycuda

johnnycuda

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Having trouble with the install.
I ran a 12 volt hot to the the ballast resistor and the other side to the + side of coil like the directions said.
Dosnt seem right because I only have 5-6 volts at the coil after going threw the ballist +
Does this sound wrong?
Help I’m stumped dos t take much. It’s aLso getting hot at the Distributor and the ballast resistor
 
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The coil only runs on 6 volts, you should be good...

Follow the wiring diagrams, and make sure that the control is grounded well...
 
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Ballast resistor reduces run voltage to the coil when switch is in run position. The switch and cars wiring sends full available voltage to the coil in start position only. So... In run, if you have 12 volts into the ballast resistor you'll have 7 or so out to the coil depending on what resistor you have. You haven't told us enough about what vehicle or parts you have or why you're doing this in the first place. Some of these old vehicles here have major voltage drop issues in their 50+ year old electrical. A ballast resistor is what it is. Low voltage in is equally low voltage out. Where 12V in equals 7V out, 10V in equals 5V out. Points ignition would operate decent on low voltage. Electronic ignition will not.
 
That doesn't sound right.
Are these the instructions you have?
screenshot_2_55f12516eb14635e81f64e98b95c847feb7eb786.jpg

The only "hot" wires are switched feeds from your ignition switch: "Ignition 1" (run) and "Ignition 2" (start). Basically the same wires that were there for your points ignition. Do NOT use a constant hot.
Yes, the voltage through the ballast will drop; that is the purpose of the ballast. The system provides full voltage for starting and reduced voltage for running- full time constant 12v will cook your ECU (unless you run an ECU specifically designed for constant 12v).
 
68 barracuda 340
I bought the car with the distributor and ECU missing
And was giving the Mopar electronic distributor and orange box with my purchase.
I initially dropped the Dist in and the orange box in and it fired right up I thought I was good.
Then I went to get gas for the first time and barley made it back it would stall wait cool off start back up made it home.
So I figured I’d better use the ballast resistor it came with and harness but no luck firing it now.
Maybe coil crapped out?
 
Professor Fate said:
That doesn't sound right.
Are these the instructions you have?
View attachment 1715785518
The only "hot" wires are switched feeds from your ignition switch: "Ignition 1" (run) and "Ignition 2" (start). Basically the same wires that were there for your points ignition. Do NOT use a constant hot.
Yes, the voltage through the ballast will drop; that is the purpose of the ballast. The system provides full voltage for starting and reduced voltage for running- full time constant 12v will cook your ECU (unless you run an ECU specifically designed for constant 12v).
Click to expand...
Yes those are the ones I have
 
johnnycuda said:
68 barracuda 340
I bought the car with the distributor and ECU missing
And was giving the Mopar electronic distributor and orange box with my purchase.
I initially dropped the Dist in and the orange box in and it fired right up I thought I was good.
Then I went to get gas for the first time and barley made it back it would stall wait cool off start back up made it home.
So I figured I’d better use the ballast resistor it came with and harness but no luck firing it now.
Maybe coil crapped out?
Click to expand...
Good guess but when a coil overheats to failure it can dump oil out the nose/tower. They dont come back. If you have a very old 5 wire orange box that needed a dual ballast resistor and it got full 12 volts... Any of the early electronic ignition modules had temperature related failures, Ford, Chrysler, you name it. Chrome box for 4 wires and single ballast resistor to protect coil is the way to go.
 
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RedFish said:
Good guess but when a coil overheats to failure I can dump oil out the nose/tower. They dont come back. If you have a very old 5 wire orange box that needed a dual ballast resistor and it got full 12 volts... Any of the early electronic ignition modules had temperature related failures, Ford, Chrysler, you name it. Chrome box for 4 wires and single ballast resistor to protect coil is the way to go.
Click to expand...
So you think I fried the ECU? And the coil is still good?
 
Are you sure the coil is 'correct'? Some coils do not get used with bal res; coils that do get used with bal res have to have a bal res of the correct resistance for THAT coil.
 
Some thing is wrong the distributor shoud not get hot from electric at all period. Suspect a fake ECU have a picture of the top of it?
 
Professor Fate said:
That doesn't sound right.
Are these the instructions you have?
View attachment 1715785518
The only "hot" wires are switched feeds from your ignition switch: "Ignition 1" (run) and "Ignition 2" (start). Basically the same wires that were there for your points ignition. Do NOT use a constant hot.
Yes, the voltage through the ballast will drop; that is the purpose of the ballast. The system provides full voltage for starting and reduced voltage for running- full time constant 12v will cook your ECU (unless you run an ECU specifically designed for constant 12v).
Click to expand...
THOSE INSTRUCTIONS ARE NOT CORRECT


The wire shown at top right running off they are calling "START position" is not correct. You do NOT want to connect that to the "start" wire because in park or neutral, or with a stick car, the start relay will bleed off power from the coil

As mentioned, that wire goes to IGN2 which is already present. IN FACT the stock factory wiring to the coil and ballast resistor IS UNCHANGED.

You want to check coil positive to ground DURING CRANKING. The coil+ should see "same as battery" during cranking and that should be 10V or more minimum

A few things:

Make CERTAIN absolutely CERTAIN that ECU is GROUNDED. Scrape around the bolt holes and mount using star lock washers

Make certain ECU is getting FULL battery power to the appropriate wire either with key in "run" or during cranking

Turn key to "run." "Rig" coil wire to a test gap or plug. Separate the distributor connector and take the ECU end of the connector in hand. Tap the bare prong repeatedly on a ground point. Each time you do so should produce one single "snap" blue spark

Distributor: Remove cap, inspect for shaft wear and play, bent, or other damage. Look for "strike" damage between reluctor and pickup coil. Look for any filings, rust or other debri stuck to either. Connect your multimeter on low AC volts. Rotate dist either spinning by hand (out of engine) or with starter. Dist pickup should produce about 1V AC
 
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There should be NOTHING getting hot at the distributor. There should be no current or power of any kind going to or from the dist pickup wiring If you did not "chop up" the distributor wiring in the supplied harness, there is something "bad" likely defective box, and it may have burned up the dist. pickup
 
I can't tell from your photo what goes where and I'm going to say "no." Where is your original ballast wiring and what did you do with that?

It appears you do not have the IGN2 bypass circuit wired in, which must supply power to the coil (and back to the box) for starting

Have you tested cranking voltage to the coil?
 
Fake ecu bet it is bad look in the how to thread. MP sourced them out and they are a "licensed product" Easy to tell it has a fake transistor. They usually fail hot also and work agin cool.
 
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Can I ask a dumb question should the negative side of the coil be getting 12v hot with ign on?
 
Just that side? Shoulld be even across. Put another ECU in to test it. Make sure it is a reall one.
 
halifaxhops said:
Just that side? Shoulld be even across. Put another ECU in to test it. Make sure it is a reall one.
Click to expand...
No I mean with the key on and 12 V going to the coil the negative side is hot also?
Bad coil?
I think I had the ECU disconnected when this happen
 
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So I re checked all the wiring several times. I’m getting 5 volts to coil constant with key on
When cranking I get 12 volts which should be correct.
With key on ballast res gets really “hot” to the touch. Is the Coil or ECU bad or both? Other issue?
 
johnnycuda said:
So I re checked all the wiring several times. I’m getting 5 volts to coil constant with key on
When cranking I get 12 volts which should be correct.
With key on ballast res gets really “hot” to the touch. Is the Coil or ECU bad or both? Other issue?
Click to expand...

The ballast is supposed to get hot. That's why it's ceramic. It's cutting battery voltage (12v or more) down to about 6-7 volts. It's GONNA be hot. You're probably good. Your voltage is a little low at the coil I bet because your battery is a little down.
 
I don't know if this helps ya' but FWIW,
This is part of what came with my distributor kit. It's worked just fine since maybe '86 or so with my '69 stock harness. I am not currently running the 534 chrome box, coil, ballast set, but a "real" Mopar orange with appropriate coil and ballast. I also run the 732 VR.
When checking for keyed power, both connections on the ballast need to be removed.
In key "start" you should have power to Ign2 connector ONLY, nothing on the other.
In key "run" you should have power to Ign1 connector ONLY, nothing on the other.

upload_2021-8-25_9-3-44.png

upload_2021-8-25_9-5-4.png

upload_2021-8-25_9-6-44.png

upload_2021-8-25_9-8-13.png
 
Daves69 said:
I don't know if this helps ya' but FWIW,
This is part of what came with my distributor kit. It's worked just fine since maybe '86 or so with my '69 stock harness. I am not currently running the 534 chrome box, coil, ballast set, but a "real" Mopar orange with appropriate coil and ballast. I also run the 732 VR.
When checking for keyed power, both connections on the ballast need to be removed.
In key "start" you should have power to Ign2 connector ONLY, nothing on the other.
In key "run" you should have power to Ign1 connector ONLY, nothing on the other.

View attachment 1715786277
View attachment 1715786279
View attachment 1715786281
View attachment 1715786283
Click to expand...
Thanks, thats how it set up now.
12v with key on at #2
And at run nothing only to #1
I originally ran it with the orig Harness 5 wire installed and it ran for about 1/2 hour total time over 2 days then died dead.
apparently somthing blew out. trying coil today but i suspect the box may have went.
I just called mopar performance the maker of the setup and he is sending a new orange box He seems to think I got a bad one
 
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