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  #16 (permalink)  
Old 02-12-2013, 05:45 PM
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Quote:
Originally Posted by EOD Guy View Post
All good advice above, except you do not have to disconnect the wires from coil to check the "S" wire.... it's only energized when the key is in start and it's only function is to supply voltage to engage the soleniod etc.......

The "I" wire will get backfeed from the resistor wire to the coil etc...... but it's designed to provide 12v to the coil so that shouldn't be an issue, however if it's not disconnecting from the starter solenoid feed then...... it makes sense that that's where the 14 volts are coming from...

Try disconnecting the "I" wire from the coil and see if you are getting voltage on the wire with the key in start, then turn the key to run and it should go dead...... if it's not, check and make sure the ring terminal on the starter end of the wire isn't making contact with lg lug with the battery cable at the starter...... which I suspect is your issue.


Maybe I missed something but I did not see where anyone suggested disconnecting the coil wires to check the "S" wire which as you correctly point out would not be necessary. The "I" wire from the solenoid however must be disconnected from the coil (or the output side of the resistor if it happens to be connected there instead) otherwise it would show voltage from the output side of the resistor. The "I" wire from the solenoid might be connected to the coil terminal, output side of the resistor or anywhere in between since this is not a factory installation.



Sequence to check,

1-Check for 12 (0r slightly higher) volts on the input side of the resistor with switch in "run".

2-Check for 8+/- volts on the output side of the resistor (better if points are closed during this check to load the resistor) with switch in "run".

3-Check for 8 to 12 volts on the wire from the solenoid while the engine is cranking and wire is disconnected from coil/resistor.

4-Check to make SURE the wire from the solenoid does NOT have voltage when the switch is released from "start" to the "run" position.


Step 3 voltage can vary wildly from almost full normal system voltage to being quite low, how much variation from normal system voltage will be determined by things like engine size (starter load), battery charge level, battery size/rating and battery condition. A relatively new, large and fully charged battery will show very little voltage drop during this check while a smaller and or older battery in less than top condition could show a lot of drop so the only thing important for this check is to make sure there is voltage on this wire while cranking but that it goes dead when the starter is disengaged.

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  #17 (permalink)  
Old 02-12-2013, 05:55 PM
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Quote:
Originally Posted by EOD Guy View Post
All good advice above, except you do not have to disconnect the wires from coil to check the "S" wire.... it's only energized when the key is in start and it's only function is to supply voltage to engage the soleniod etc.......

The "I" wire will get backfeed from the resistor wire to the coil etc...... but it's designed to provide 12v to the coil so that shouldn't be an issue, however if it's not disconnecting from the starter solenoid feed then...... it makes sense that that's where the 14 volts are coming from...

Try disconnecting the "I" wire from the coil and see if you are getting voltage on the wire with the key in start, then turn the key to run and it should go dead...... if it's not, check and make sure the ring terminal on the starter end of the wire isn't making contact with lg lug with the battery cable at the starter...... which I suspect is your issue.
The s wire is used to engage the starter, the I wire feeds the ignition system while the starter solenoid is engaged.
As I said disconnect everything from the + side of the coil except the resistor and run a feed to the other terminal on the resistor and see if the voltage readings are normal. If it is there is voltage somehow being fed from the other wire back to the coil.
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  #18 (permalink)  
Old 02-12-2013, 06:10 PM
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Quote:
Originally Posted by T-bucket23 View Post
disconnect everything from the + side of the coil except the resistor and run a feed to the other terminal on the resistor and see if the voltage readings are normal. If it is there is voltage somehow being fed from the other wire back to the coil.


Not at all trying to disagree but this is puzzling? You are saying to disconnect all wires to the (I) terminal on the coil except the one from the resistor and then connect a full voltage wire to the input side of the resistor, am I understanding that so far? Then after connecting the hot wire (full voltage) to the input side of the resistor check voltage at the coil, is that correct? If so then it would be expected to have a voltage to the coil but this voltage would be slightly lower than the voltage on the input side of the resistor, not sure but maybe I am misunderstanding here.


Easy to get "wires crossed" when discussing electrical matters!
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Old 02-13-2013, 07:13 AM
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thank you to all who posted their suggestions. I did a lot of what was stated here.
The only thing that has given me some success is to disconnect wire from solenoid to coil side of resistor. The car runs better now. I DID NOT hook it back up to see if problem comes back. Car starts fine without it. I also did some research and got specs on ohm readings for resistor. My original read 1.2 ohms, the new one reads 2.1 which is what it is supposed to be, dont know if that was problem, but I am not putting the old one back on to find out. Thanks again, rick
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Old 02-13-2013, 07:38 AM
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Originally Posted by choirboy View Post
The car runs better now. I DID NOT hook it back up to see if problem comes back. rick

That wire should not make any difference at all, NONE, in the way the car runs unless it is possibly grounding somewhere. In that case it could cause all kinds of problems! As far as hooking it back up, I was going to suggest just unhooking it and leaving it off because it's only purpose is to bypass the resistor to help during starting, if your battery is fully charged and in good shape (and also large enough) then you will most likely never need that wire and never miss it. HOWEVER, be warned if the battery gets low or as it gets older and not able to supply a lot of starting AMPs you may very well then have starting problems because the voltage will drop a lot lower under starting load. Also really cold weather might (or might not) be a problem, it depends on how easy your engine fires. As long as your battery can supply a lot of AMPs to the starter you will not have a problem but a weak battery or a low charged battery may not be able to hold the voltage high enough to make a hot spark during start, the less battery capability the greater the voltage drop to the coil. If the battery gets discharged to the point that the engine is turning over slowly during start the voltage could very well drop low enough for the coil to fail to fire at all, of course none of that matters in the least after the engine is running.
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Old 02-13-2013, 11:03 AM
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Old Red makes a very valid point

I have an 82 Dodge pickup that I bypassed the lean burn computer on and used a stand alone ignition system.

The stand alone required a different coil and distributor
when I wired it all up, I made no provisions for 12 volts at startup to the coil.

If the car sits long enoough for the battery to weaken------it will not start and won't even try, but the engine will spin like nothing is wrong.

I have the wiring in place to provide the 12vdc while cranking----but have yet to get a necessary diode so that the starter will shut off-----Dodge relays---weird
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  #22 (permalink)  
Old 02-14-2013, 05:10 AM
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You fellas are quick to jump on............"Maybe I missed something but I did not see where anyone suggested disconnecting the coil wires to check the "S" wire"

Nor did I state someone suggested it. I just clearified that you didn't have to, as one poster suggested remove all the wires from the coil etc.....
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Old 02-14-2013, 06:51 AM
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I mentioned removing the wires from the + side of the coil

only to check the switching in the solenoid.
easier to do that than to crawl under the car and do it.

Just trying to make sure that ignition contacts in the solenoid were not sticking when the starter was not running.
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Old 02-15-2013, 08:33 PM
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thank you to all. I think all is working now, I will know tomorrow afternoon when I go for a cruise.
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  #25 (permalink)  
Old 02-15-2013, 09:18 PM
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What did it end up being?
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Old 02-16-2013, 10:06 PM
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Well, I disconnected wire that comes from terminal on solenoid and goes to coil side of ballast resistor (to supply 12 volts while cranking). I also changed my ballast resistor because I was getting full voltage at coil. I then started the car and it idled better and did not start missing after about 5 minutes as it was doing.
Today I took the car for a ride and if I stay easy on the gas pedal all is fine. BUT if I step on it, the car misses and I get small backfires. I do have three deuces for carbs, but I do not think it is when the secondary carbs are kicking in. I walked away a little disgusted and didn't look at any thing. I am thinking that I am still getting too much voltage at coil/points and it is breaking up. I do have a set of plates that I can put under secondary carbs to eliminate any problems there. I may do that tomorrow.
I took my old and new ballast resistors and hooked up to my battery charger, I got 12 volts on BOTH sides with both of the. I did however get two different ohm readings: 1.2 on the old one and 2.1 on the new one. I thought that may have been the cure. No luck Rick
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Old 02-16-2013, 10:08 PM
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I am also thinking about a new electronic distributor. I just don't want to throw money at a problem that may be something else. If that makes sense
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  #28 (permalink)  
Old 02-17-2013, 06:41 AM
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If you put an HEI Dizzy you will elimiinate the whole voltage thing. The HEI is designed to run on a full 12 volts....... If you decide to go that route make sure you don't use the old resistance wire to pwr the new HEI.

Try this for your old system......
Unhook your ballast resistor from the feed side, leave it hooked to the coil, run a temp jumper wire from the battery to the feed side of the resistor....... see if it runs better. You may have to pull the jumper in order to shut off the motor.

If you have a known good coil I'd try that also, it doesn't take long for 12v to burn up that new coil you put in.
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Old 02-17-2013, 07:50 AM
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is there a resistence wire? I assumed the ballast resistor did it all. Thanks, Rick
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Old 02-19-2013, 12:01 PM
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If you are getting 12 volts to the input side of the resistor then there is no resistor wire in the circuit, some systems had resistor wires and some used an external resistor but no system uses both at the same time. If you are just checking the voltage on that resistor with no load on it using a DVM multimeter then I doubt you will see any voltage drop because those things are linear and voltage drops with load. With all the wires hooked up (including the one from the resistor to the coil) except the one from the solenoid check the output voltage from the resistor with the points closed to load the resistor and I bet you will get a lower voltage reading.
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