And in regards to replacing the under dash and hood wiring harness, it's in the works for this summer...right now it isn't possible since I need this truck daily.

 

Understanding that he needs to find the problem, surely a little maintenance like making sure connections are good (which he stated were loose) and insulating can't hurt since it's a dd. Eh?

 

That's correct; the point I've tried to make is that these problems are important and ultimately need to be addressed, but don't explain the behavior described here. I think we're saying the same thing.

Nope, that's correct.

Yes, always avoid bargain-brand or "Blue Streak" parts. You've already indicated that you continuously have to bend the coil wire to make it fit and the blue discoloration is an indication that it's not seating correctly and part of the spark is occurring in the connector itself. That's a huge red flag.

 

I'll have to pick up those parts and install them. I guess my remaining question is in regards to this resistor. I know what it does, but do I need it? Where does it tie in? If I get a 12v coil, do I need it?

Im just trying to avoid frying a new, good coil...in hopes of getting rid of this issue...

 

Sorry for the slight hijack.
But this interests me because I'm seeing a pattern with Standard Blue Streak parts.
I have a great parts store by me, I always ask for American made quality parts. The parts I have been getting lately (for my rebuild) are Standard Blue Streak. The first voltage regulator I got from them was bad. Others in the forum have had negative Blue Streak comments.
Would you or anyone else that has knowledge of this please comment fmc?

 

The factory ignition system requires a ballast resistor as well as a coil that expects an external ballast. The power dissipation properties of the power transistor in the ignition module assume the resistor is in place for reduced primary current.

The resistor is a long length of wire bundled in the dash harness. It's implemented as a long wire rather than a single unit to help dissipate heat.

Coils marked "12 V" are ambiguous because it's not clear if the coil expects 12 volts across the primary winding, or if the coil is meant to be installed in a 12-volt system that may or may not have the resistor. I don't think the "12 V" marking is meant to imply anything about a ballast resistor necessarily, it may simply be for delineating it against older 6-volt systems.

Some coils are marked "used with external ballast" which is completely clear. A coil made for a factory Duraspark system should expect an external ballast. The primary resistance of the coil may give a clue (if it's on the order of 1 ohm, it likely expects an external ballast). You need a ballast regardless since you have the factory Duraspark module.

I've heard nothing but bad things about Blue Streak parts. It's the cheapest line that Standard offers. My truck is currently parked while I'm in the middle of an electric fuel pump conversion. While waiting for parts to come in, I've done a tune-up, including trying Blue Streak stuff for the first time. I haven't ran the engine much with them yet but the parts feel very cheap.

 

Okay that makes much more sense about the resistor. I've done some searching in my free time about it, and never quite came to a common consensus on whether one is needed or not. You say it should be bundled up behind the dash? Where about should that be? I checked all up around the gauge cluster, ignition switch, etc areas...from what Ive read, it should be a fat pink wire that says "do not cut or splice" on it. To my knowledge (and eyesight), I didn't see it.

Good to know about the coils as well. The newer BWD one I have says "for use with 12v electronic ignition only". The older Ford ones say "for use with external regulator only". As I said above somewhere, I have a lead from an older parts store that they still have a Ford coil in stock that's NOS. Is the resistor wire sold seperately or how can I obtain one if mine is indeed missing?

Mind the stupid questions...I'm just trying to avoid more breakage and wasted money and headbanging.

 

The resistor wire can be bought as a length of wire from a place like Rock Auto. Chrysler used solid panel-mount resistors with spade terminals that can be made to work too.

The resistor wire may be hidden behind tape. It should be RED with a GREEN stripe, not necessarily PINK. Someone would have really wanted to get rid of it to get rid of it.

 

From what I've seen in wiring diagrams, it comes off the I post on the starter solenoid, correct? If it's buried in tape, that explains why I don't see it. So then how would I go about replacing it if it's all wrapped up? I'm just trying to figure out the best plan of attack on how to even go about replacing this thing.

 

It makes an electrical connection to the 'I' post of the solenoid by way of the start bypass circuit, but it's not physically located under the hood at all. If you must replace it, you can just bypass it and leave the old one in the tape.

Note, however, that you do have a ballast resistor in your setup already. It shows up in the coil voltage measurement you took with the key in RUN. If you did not have a resistor, the coil voltage would be equal to the battery voltage. The added resistance that's responsible for the low number you measured is likely downstream or upstream of the ballast, meaning replacing the ballast resistor may or may not address that particular issue. It doesn't really make sense to be researching how to replace a ballast resistor right now in fear that you don't have one when you should. You do have one, it may or may not be related to the non-ideal coil voltage you measured, and it's not related to the no-start issue based on the observations you've stated.

 

Okay then I will not worry about replacing it. Ha that probably just saved me a ton of work. But then what could be causing the non standard coil voltage? Too much resistance in the ICM? Bad grounds?

 

I listed the causes in one of my first posts. Unwanted resistance through the ignition module or bad ground at the distributor would cause an increase in coil voltage with respect to ground. Those are all downstream of the coil primary winding. I've mentioned a couple times that the problem has to be upstream.

 

Alright after rereading all this that makes sense. I think I will replace all these cheap replacements with decent quality parts and see where it goes from there.

On a somewhat side note, I know my distributor is one of those BWD replacements...therefore its got a cheap pickup coil in it. Would it be worth replacing the pickup coil as well then? I'm still somewhat confused on primary vs secondary parts of the ignition...

 

The pickup coil is on the primary side of the ignition system. If the coil switches at all, the pickup coil is fine.

Primary side refers to the low-voltage, high-current side of the ignition system, including all of the control electronics. The ignition key, ballast resistor, half of the coil, ignition module, and distributor pickup module are all part of the primary side. Secondary side refers to the high-voltage, low-current side of the ignition system. This includes the other half of the coil, plug wires, distributor cap, rotor, and plugs themselves.

The coil bridges the primary and secondary sides. As such, the coil has both a primary and secondary winding. Energy is transferred from the primary winding to the secondary winding through the use of an electromagnetic field. It's the exact same mechanism behind AC power transmission with transformers (in fact, an ignition coil is called an "auto-transformer").

 

Interesting. So from the sounds of it, combined with what you've said, the low voltage at the coil is being caused by higher resistance upstream...I assume therefore somewhere on the secondary side? So possibly the cheaper wires or questionable cap/rotor contact?