Maybe dumb ballist question

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Originalowner73 340duster

Originalowner73 340duster

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I'm converting to two prong ballist with my new system . I got.new distributor harness and module.coil and ballist.. question is I got the keypower on side but the key on start power side was never on my car on prong ballist???. Can I just hook up as is or should I run a jumper to the yellow key power on at relay..and then if I do run the jumper to the relay from other side of ballist which goes to/from positive side coil won't it run power back threw the yellow wire and activate starter??
 
First go to Mymopar and in the reference section find your wiring diagram. if you are using a wire harness from another model / year car pull that one up as well.
trace out the start cir and the run cir and see if it looks like what you are working with

I think we all need a bit more info.
 
upload_2018-10-2_16-27-34.png
 
Dana67Dart said:
View attachment 1715230523
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Yes and that is pretty much what instructions said...but when looking a scematic won't the power from the ballast power the yellow wire when running and activate the relay?? Or will it not power backwards that way ...power constant on other side if ballist when running...am I just not understanding the flow direction..
 
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Also wonder y the car is not like that ..has a jumper on right side and unused wire from module going to top left of ballist ...guess another one of my dad's rigs..lol
 
Originalowner73 340duster said:
Yes and that is pretty much what instructions said...but when looking a scematic won't the power from the ballast power the yellow wire when running and activate the relay?? Or will it not power backwards that way ...power constant on other side...am I just not understanding the flow direction..
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The dark blue wire from the harness "ON" provides constant 12V to the ballast resister and to the ECU.

The 12V then travels through the resister to the coil.

Under starting (Crancking) conditions the yellow wire puts 12V directly to the coil and as soon as you release the key the dark blue wire takes over.

There is no issue applying 12V to both sides of the ballast resister.
 
As set up now..blue wire on top left bottom left blue from module and a jumper wire up and down..right side is brown positive from coil on bottom and unused green from module on top, on ballist 4 prong in car now
 
Thought it was that simple but just wanted to make sure.. my dad ripped alot of stuff out and rigged alot of stuff he used ro drag it.. I had no problems when I drove 20 yrs ago..and have been fixing correctly and updating as I go this past few yes .
 
If i'm not mistaken the duel ballast was used on the 5 wire ECUs. one resister fed the ecu and the other fed the coil. Newer ECUs use only 4 wires and do not need the duel ballast so there might be jumpers here or there if the ECU was replaced at some time.
 
Dana67Dart said:
If i'm not mistaken the duel ballast was used on the 5 wire ECUs. one resister fed the ecu and the other fed the coil. Newer ECUs use only 4 wires and do not need the duel ballast so there might be jumpers here or there if the ECU was replaced at some time.
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Yes has crome one..guess he just never had the extra cranking volts to the coil on start up.... Also has no electronics for choke ..lol..
 
Yes that's my scematic now ..just without the ignition 2 hooked up and has a jumper on other side..so was acting as a single ballist anyway.
 
Also they said to start at 5' advance to start and run it. Without vacuum advance of course..seems low to me..also I never ran car with vacuum advance..looked up how to do it ..but just had the question on werre they said to start..and if you had any additional information of course..
 
Dana67Dart said:
View attachment 1715230523
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THIS DIAGRAM IS WRONG at least for "our cars." Notice it shows the coil side of the ballast going to the "starter relay." No such thing. The coil + side of the ballast goes to the (some years brown) IGN2 wire which comes from the ign switch (separate contact) through the bulkhead and to that point

I don't understand how your car ever started if that was not connected because on all these cars THE RUN (IGN1) goes DEAD during cranking
 
Dana67Dart said:
If i'm not mistaken the duel ballast was used on the 5 wire ECUs. one resister fed the ecu and the other fed the coil. Newer ECUs use only 4 wires and do not need the duel ballast so there might be jumpers here or there if the ECU was replaced at some time.
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TRUE!!! The coil side of the ballast is wired exactly the same as with "points." In fact if the ECU system quits, you could unplug the ECU, stab a "points" distro in there, and hook it up to the coil NEG

"The other" side of the 4 prong provided power to parts inside the ECU, earlier. Later model ECU was changed, and powered from the "full power" wire going to the box (blue ign run)
 
...wait so the single ballist diagram is wrong???My blue wire splices out before engine side of the non existent middle bulk head (all have bullet connectors).. I'm going to have to cut some of the wireing harness and see ..I'm pretty sure my brown ignition wire runs to the yellow wire on my starter relay and nowwhere else?? .. ahhh cut and play tomorrow.......
 
The one I said is wrong is OK except for the "start" wire. It does NOT go to the start relay. IN FACT you do not need to mess with the ballast wiring at all. The wiring as it is is same whether for points or ECU. All you need do, is to add the power wire from the ECU to the "high" side of the ballast. If any question, pull loose the wire you believe it to be from the ballast, and confirm it is "same as battery" with key in "run."

When you get it hooked up, confirm that you have at least 10.5 to the coil + when cranking. This will confirm the ballast circuit is working
 
Ok thanks ..I'm cutting apart the rest of harness anyway..did half of it might as well do the rest..still wanna trace my brown wire from ignition and see we're it goes...and chk all the blue wire splices..it seems to power everything..lol
 
Dana67Dart said:
http://www.mymopar.com/downloads/1973/73ValiantA.jpg
http://www.mymopar.com/downloads/1973/73ValiantB.jpg

I know not duster but fundamentally the same, also look at 73 dart service manual, SIGNIFICANTLY more complicated wiring diagram but works the same way
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Heh.........and you have to be careful because that manual is ALSO misleading. The way the ign switch is drawn would lead you to believe that the ballast bypass (IGN2) and the "start" wire to the relay are off the same switch contact. These are, essentially, separate switches in the ign switch housing, IE separate contacts. This is specifically to prevent backfeed in the coil power circuit from trying to backfeed the start relay
 
67Dart273 said:
Heh.........and you have to be careful because that manual is ALSO misleading. The way the ign switch is drawn would lead you to believe that the ballast bypass (IGN2) and the "start" wire to the relay are off the same switch contact. These are, essentially, separate switches in the ign switch housing, IE separate contacts. This is specifically to prevent backfeed in the coil power circuit from trying to backfeed the start relay
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Yes my car is (off the bulkhead) blue white has power when key is on brown wire is starting power..my car was hooked up correctly..I'm putting all new wires in the blue and white splice in with alternator,ballist and regulator..brown goes from coil to splice into ballist and into bulkhead brown ignition start
 
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