Not Getting 12 Volts at Coil

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Not to specifically address your problem, but just food for thought:
1). George R ran into this problem, had a long thread going last September. I found it helpful to my plight, you might check it out.
http://www.forabodiesonly.com/mopar/showthread.php?t=42182

2). Like George's problem, my problem was not just one thing. I found a 2 volt drop in my bulkhead, and .5 volt drop at my ballast resistor. Still wouldn't start. Last resort STARTING FLUID! Started right up. I think too much gas in the cylinders, too much other stress going on. The car needed a little kick to overcome the overtaxed ignition system.

Moral of my story: it just wasn't one thing. Hope this helps, and good luck!
 
Sounds like a bad coil - see #5 terminal 2 above.
I also have to apologize, I didnt check back. You misunderstood me. I didnt meant the ignition switch itself, but the connector ounder the dash. that is what overheats and burns/melts. However, it sounds to me like the coil might have an issue because of the above.
 
Can you post a picture of the ballast resistor wiring? According to the wiring diagram for a 74, the dark blue wire should be attached to same end of the ballast (both top and bottom connectors) with the dark blue/yellow trace wire to the ECU. On the other end of the ballast, the dark green/red trace wire should run to the ECU and the other (brown?) wire runs to the voltage regulator. The diagram shows the dark green/red trace wire on the opposite level of the dark blue/yellow trace. Say the dark blue/yellow trace is on the top row so the dark green/red trace would be on the bottom row and brown would be on top.
 
moper said:
Sounds like a bad coil - see #5 terminal 2 above.
I also have to apologize, I didnt check back. You misunderstood me. I didnt meant the ignition switch itself, but the connector ounder the dash. that is what overheats and burns/melts. However, it sounds to me like the coil might have an issue because of the above.
Click to expand...

You're right. I did misunderstand you. I previously checked that connecter under the dash that wraps around the steering column. I actually have just slightly less voltage at this connector than at the battery, starter relay, and starter. I think my connector is fine.

My coil is brand new. How do I test it to determine it is good? I do have a multimeter.
 
I went to the garage and took the wires off the + and - coil and also pulled the high tension lead in the center of the coil. I took out my ohmmeter and got the following results:

Checking Primary Resistance
20k - 0.00
200k - 00.0
200 - 2.0
2000 - 002

Checking Secondary Resistance
20k - 9.22 to 9.23
200k - 9.1
200 - Nothing
2000 - Nothing

I did the same test on another older coil and got almost the same readings. Is this coil good or bad?
 
Dartnewbie said:
Can you post a picture of the ballast resistor wiring? According to the wiring diagram for a 74, the dark blue wire should be attached to same end of the ballast (both top and bottom connectors) with the dark blue/yellow trace wire to the ECU. On the other end of the ballast, the dark green/red trace wire should run to the ECU and the other (brown?) wire runs to the voltage regulator. The diagram shows the dark green/red trace wire on the opposite level of the dark blue/yellow trace. Say the dark blue/yellow trace is on the top row so the dark green/red trace would be on the bottom row and brown would be on top.
Click to expand...

Here is another link with a clear picture of the dual ballast and wires.
http://www.forabodiesonly.com/mopar/showthread.php?t=58332&highlight=74+ballast

My wiring is actually different. Is this one correct? Does it matter if the wires are not hooked up like the FSM shows?
 
clifftt said:
Not to specifically address your problem, but just food for thought:
1). George R ran into this problem, had a long thread going last September. I found it helpful to my plight, you might check it out.
http://www.forabodiesonly.com/mopar/showthread.php?t=42182
Click to expand...

I just spent 1 1/2 reading 200 posts between mid August and August 30 helping George with his issue that sounds a lot like mine. He had several people a day responding to his pleas for help. I am just as frustrated as him and am even madder because I have not received a single answer today. Today is Saturday and I have time to work on it.

Please guys, I need answers to my the last three or four posts I made today. ANYBODY!
 
1974DartSport said:
Here is another link with a clear picture of the dual ballast and wires.
http://www.forabodiesonly.com/mopar/showthread.php?t=58332&highlight=74+ballast

My wiring is actually different. Is this one correct? Does it matter if the wires are not hooked up like the FSM shows?
Click to expand...

Well I would think if they are different it could be a problem. That's why I asked for a picture of what you have now. Wire colors can be different as long as they are doing the same thing in both cases. Could you at least describe how yours is wired with wire colors if possible? I think the FSM wiring method is the way to go unless that is not working for you.
 
Here is a pic of the ballast wiring in my '74 Duster. Randy and I have talked before, and I think his wiring is slightly different. As stated above, all the wires could be the same color, as long as their connections are correctly oriented. If his car ran for years wired as it is, there is no good reason to believe it shouldn't now. The question becomes, are the OTHER ends of the ballast wires connected to the right component.

This is my wiring layout:
A = dk green w/ red tracer to harness (looks like from ECU)
B = brown to connector, then to harness (maybe +coil)
C = brown to harness (maybe to starter interlock switch, also ignition switch)
D = blue jumper
E = dk blue to harness (maybe to voltage regulator, also EGR timer)
F = green (maybe faded blue) w/ yellow tracer to harness (looks like from ECU)

Don't you just love electrical gremlins...

Jerry

Ballast Wiring.JPG
 
While we are at it tracing wires, let's look at the starter relay:

A = 10ga red from +battery
B = 10ga red to fusible link at bulkhead connector
C = 12ga brown to starter
D = 18ga brown to EGR timer
E = 18ga yellow to starter interlock switch
F = 20ga brown w/ yellow tracer to neutral safety switch at transmission

Starter Relay Wiring.jpg
 
1974DartSport said:
My wiring is actually different. Is this one correct? Does it matter if the wires are not hooked up like the FSM shows?
Click to expand...

Looks like mine are wired just like this one you referenced from another post (just not as clean and pretty).
 
The problem is not the ballast. I have no spark at the spark plug wires. I bought a spark plug tester and tested plugs 1, 2, and 3. No fire at either of these three plug wires. It's either the distributor, high tension coil/distributor wire, spark plug wires, or a wiring issue. I'll work on one at a time and eliminate each.
 
OK folks, now we're getting somewhere. Here's what I understand so far:

The battery is charged and has good cables
The ignition switch works
The starter engages
The neutral safety switch is connected and checks good
The dual-ballast resistor is connected properly
The ECU is new and has an extra ground wire
The voltage regulator is new and has an extra ground wire
The coil is new (checks good ?) and is wired properly but not getting 12V
The coil has a hot lead directly from the battery to the + post to get 12V
The fuel pump and filter are new and deliver gas to the carb
The carb is rebuilt and is getting good gas (even tried starter fluid)
The distributor was checked and is OK
The ignition wires are installed in the proper firing order
The plugs are new and gapped properly
The timing chain is new
The windshield is clean and the tires are aired up

Why won't this ol' girl fire up? What's preventing it from getting fire to the plugs? What's missing from the formula?

The one thing I don't remember you saying, Randy, is whether you actually pulled the cap off the distributor and saw the rotor turn with a quick bump of the starter. Do you know if the old nylon gear on the shaft is engaging the cam?

I'm about out of ideas myself,
Jerry
 
On the coil... you are checking terminals, right? So the resitance on the primary side was 2ohms between the coil + and - terminals. No problem there. Was there infinate resistance between the case and the terminal(s)? ON the coil secondary... Again, you checked between the case and the center post and got infinate, and between the + or - and the center post? I just want to make sure you are checking the circuits properly...

Also, you have looked at the bottom of the cap to verify the nub is there to touch the rotor, right? Did you check to make sure the dist is rotating when cranking? Have you taken a spark plug and grounded it while turning the engine to verify no spark? Not just assuming because there is no popping or running engine that there is no spark.

I apologize if you've done it all the right way.. I'm just making sure.
 
1974DartSport said:
I bought a spark plug tester and tested plugs 1, 2, and 3. No fire at either of these three plug wires.
Click to expand...

That's what I was wondering, but it sounds like he has this taken care of.

[QUOTE='74Sport]...you actually pulled the cap off the distributor and saw the rotor turn with a quick bump of the starter. Do you know if the old nylon gear on the shaft is engaging the cam?[/QUOTE]

Moper, it sounds like we are on the same page.
icon10.gif


This is a real head-scratcher...
 
'74 Sport said:
The one thing I don't remember you saying, Randy, is whether you actually pulled the cap off the distributor and saw the rotor turn with a quick bump of the starter. Do you know if the old nylon gear on the shaft is engaging the cam?

I'm about out of ideas myself,
Jerry
Click to expand...

Yep it turns. I pulled the dizzy cap again tonight and had the wife try to crank the engine. The rotor turned as it was supposed to. The distributor was out of the block for a long time while my son and I restored the body. The gears on the dizzy are fine.

Next step - How do you test the pickup wires?

I'm also having trouble finding original style spark plug wires and a new high tension coil/distributor wire made of copper wire. Who sells them "Made in the USA"? eBay auction 290248073927 is selling the style that I want, however they are silicone spiral core wires.
 
I was given the following distributor instructions to do:

If the measurements are off, or if you want to set it anyways just to be sure, here is how you do it:

1. Get a Feeler Gauge set (can be found at any auto parts store)

2. Rotate the gauges until you come to the one that is .008.

3. Rotate the dizzy until a star point is lined up with the point on the magnet block.

4. Insert feeler gauge between the two points. If the feeler has some resistance to passing through the two points, they are probably ok. If it is too tight, loosen the flat-head screw and move the magnet away from the star point until the feeler gauge will pass through with little resistance. If it is too loose, then do the opposite, and move the magnet closer to the star point.

Then always spin the dizzy and make sure that none of the star points hit the magnet. If you really want to be thorough, check all of the star points against the magnet. You will want to set the gap with the feeler gauge to the one that is closest to the pickup to start with.


After I tested the resistance on the pickup wires to be 455, I read my FSM on how to check measurements on the distributor. Just as instructed above, I manually spun the rotor and noticed the six star points on the reluctor were just barely touching the point on the pick-up coil assembly. Using a flat head screwdriver, I loosened the screw holding the pick-up assembly and reset the gap to .008. I reinstalled the distributor, plugged in the pick-up coil wires, rechecked for a good connection of all six plug wires in the dizzy cap and the high tension center wire, plugged all six wires back to the correct sparkplugs and center of coil. I sprayed a little starter fluid down the carb and began cranking. Only 6.7 volts at + coil terminal in run. It did not fire up.

What else can I do?
 
ive never ever had to adjust a elec dizzy,, but i did read some where to use only a brass feeler gauge,,,
not to be a smart buttt, do you have the coil hooked up backwards ??

how do the connections in the 4/5 pin plug on the brain look inside??

any chance you have a points dizzy laying around, to get it started ?
 
fstfish66 said:
ive never ever had to adjust a elec dizzy,, but i did read some where to use only a brass feeler gauge,,,
not to be a smart buttt, do you have the coil hooked up backwards ??

how do the connections in the 4/5 pin plug on the brain look inside??

any chance you have a points dizzy laying around, to get it started ?
Click to expand...

I don't have a brass feeler gauge. I don't know if this could have created a problem.

It's a brand new 5 pin Mopar ECU. The wires look great. No corrosion or cracked wires.

Never owned a car with points dizzy.

I will gladly fork out $52 for a new dizzy if mine is bad. Nobody answered my previous post asking if the tests on my dizzy proved it good or bad.

The coil is definitely hooked up correctly.
 
Try taking the distributer out, spin it by hand with the ign. switch in the run posistion. With a spark plug taken out and grounded, you should be able to see if the spark is hotter. Do not do this with a bunch of fuel in the cylinders as it might blow apart your muffler.
My car had a similar problem. It turned out to be a rebuilt starter that had a short in it. It was draining the ign. system of voltage when I turned the car over.
 
I've only been into mopars sense 1962 so this may not count for much. Every thing you've said says the pluigs are not getting fire. And I don't see where you checked. Take out #1 spark plug and put the plug wire back on it. Get someone to to turn the starter while you hold the plug to a good ground. If it don't spark you have one of three things. A: A bad distributor pickup, B: A bad control box {I don't care if its new] or C: Both parts are bad. I the start position you by pass the resistor and go right to the control box, a good box will put 12 volts to the coil and 8.5 in run. If it was my car I'd warrenty out the control box and replace the pickup in the distributor. If it gets fuel and fir at the right time its got to run.
 
1974DartSport said:
The problem is not the ballast. I have no spark at the spark plug wires. I bought a spark plug tester and tested plugs 1, 2, and 3. No fire at either of these three plug wires. It's either the distributor, high tension coil/distributor wire, spark plug wires, or a wiring issue. I'll work on one at a time and eliminate each.
Click to expand...

This is where Randy posted the plug test results earlier in this thread. I've been on the phone with him a few times, and I convinced him to buy an inline spark plug tester, so he can see the tool while cranking the engine by himself.
 
bobscuda67 said:
Try taking the distributer out, spin it by hand with the ign. switch in the run posistion. With a spark plug taken out and grounded, you should be able to see if the spark is hotter. Do not do this with a bunch of fuel in the cylinders as it might blow apart your muffler.
My car had a similar problem. It turned out to be a rebuilt starter that had a short in it. It was draining the ign. system of voltage when I turned the car over.
Click to expand...

Bob, I pulled the distributor and plugged the pickup coil back in. As you said I pulled the #1 plug out and put it back in the sparkplug wire. After grounding it and the car in RUN, I had an assistant spin the dizzy rotor as fast as he could. NO SPARK. I did hear clicking as the rotor was being spun. What was the clicking noise?

So I ordered a new pickup coil wire. It will come in in two days. Tomorrow my new ECU and a new ballast come in. (Remember my current ECU and ballast are new.)

My starter has not been rebuilt. How did you find out your rebuilt starter was the cause of your problem? How do I test mine for a short?

Thanks for your suggestions. All help is welcomed.
 
Randy,
I just dug out an old distributor I had stashed and spun the shaft on it to listen for clicking you described. I believe it is probably the internal weights flying out and snapping back under spring tension. At least, that's what it sounds like to me. If you hold the rotor with one hand and try to turn the gear end of the shaft, you can feel the spring tension and hear the click when you let it snap back. Try that and see if it's the same sound.
 
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