OK Folks,
Here's what I'm thinking. I hope you can smell what I'm steppin' in! I won't bore youse guys with every detail, but want you to understand why I'm going where I am going. My plan is to install a 3G alternator, but instead of the normal way, make the charging "system/loop" separate from the main wiring harness and not worry about retaining the original gauge, etc. operation, or even adapting it or it's wiring "into" the existing harness. I mean "HECK" it only requires a sensing wire, charge wire and key on power to "excite" it for operation!
As it is, if I disconnect the alternator, all else seems to function correctly with not any dramatic amperage draw, except no charging while running. I have already, in the past, removed all accessory and auxiliary power from the ignition switch to be powered through a separately fused and powered relay.
From what I can gather, all that should be required is:
Thanks 4 Your Patience,
Gene
Here's what I'm thinking. I hope you can smell what I'm steppin' in! I won't bore youse guys with every detail, but want you to understand why I'm going where I am going. My plan is to install a 3G alternator, but instead of the normal way, make the charging "system/loop" separate from the main wiring harness and not worry about retaining the original gauge, etc. operation, or even adapting it or it's wiring "into" the existing harness. I mean "HECK" it only requires a sensing wire, charge wire and key on power to "excite" it for operation!
A) Last week a crappy Scott Drake ignition switch crapped out and in the process of generally exploding, dead shorted the main "Hot" wire feed from the battery to the switch allowing the "MAGIC SMOKE" to escape from under the dash! Be very aware that these switches are absolute junk and should be avoided like the plague!
Sooooo, after all that, back to my original 3G topic. It seems that doing the 3G install as a separate system should not cause any issues? I realize that the best solution would be all new harnesses and wiring, but I afraid they would likely be made in similar factories in "CHINESIAWANOREANAMPAN" as made the crappy switch that caused this night mare in the first place! Not to mention the price of around a Grand ($1000) by the time all is said and done.1) Upon just installing a new switch, all seemed to function but with a fairly high amperage draw. as evidenced by the little three wire plug near the puny original alternator getting pretty hot fairly quickly. Funny thing is that my "ALT" gauge actually showed some movement which it has never done before (just barely in the past) and this was my first clue that something was shorting!
2) Upon inspection, I discovered that the main feed wire, from the starter solenoid (Black w/Yellow stripe on most diagrams for 68) to the ignition switch (Yellow in most diagrams) had severely melted insulation and some wire exposed.
3) After poring over diagrams and comparing to my "bone stock, original" wiring, I determined that there is at least one junction/splice of several wires in the midst of the under dash portion of the wiring harness. Depending on which diagram you look at, there may or may not also be some sort of splice in the under hood (called the headlight harness) portion of the harness.
B) I removed the instrument cluster, etc, etc, etc. and unplugged the under dash from the headlight harness and began un-taping the harness from that end, until I got to the junction/splice and a few inches beyond.2) Upon inspection, I discovered that the main feed wire, from the starter solenoid (Black w/Yellow stripe on most diagrams for 68) to the ignition switch (Yellow in most diagrams) had severely melted insulation and some wire exposed.
3) After poring over diagrams and comparing to my "bone stock, original" wiring, I determined that there is at least one junction/splice of several wires in the midst of the under dash portion of the wiring harness. Depending on which diagram you look at, there may or may not also be some sort of splice in the under hood (called the headlight harness) portion of the harness.
1) This junction/splice is four wires: the Black/Yellow from the solenoid, Black/Orange constant power to the light switch, Black/Yellow continuing on to the constant power section of the fuse box and the solid Yellow to feed the ignition switch.
2) I then continued to un-tape the harness to the branch off to the ignition switch.
3) What I found was that the only wires compromised and/or heat damaged (melted insulation) were the Black/Yellow from the solenoid and the Yellow to the ignition switch. Even though the melted ones were slightly "stuck" to the wires adjacent to them, none of the others actually got melted.
4) I decided my best course would be to bypass/replace that Black/Yellow under the hood, along with the melted connector to the under dash harness and replace the Yellow from the "junction" to ignition switch. I neatly and nicely soldered and shrink wrapped a new junction and retaped the harness and plugged all back in for testing.
C) Before starting the car, I first turned on the ignition switch and tested amperage draw at the battery +positive and found no drastic draw.2) I then continued to un-tape the harness to the branch off to the ignition switch.
3) What I found was that the only wires compromised and/or heat damaged (melted insulation) were the Black/Yellow from the solenoid and the Yellow to the ignition switch. Even though the melted ones were slightly "stuck" to the wires adjacent to them, none of the others actually got melted.
4) I decided my best course would be to bypass/replace that Black/Yellow under the hood, along with the melted connector to the under dash harness and replace the Yellow from the "junction" to ignition switch. I neatly and nicely soldered and shrink wrapped a new junction and retaped the harness and plugged all back in for testing.
1) All gauges, accessories and lights worked normally.
D) Upon starting the car, the "ALT" gauge pegged to max and in a few seconds began to smoke. I turned the car off and quickly disconnected the battery. No other damage occurred, other than the likely demise of the "ALT" gauge.1) This inferred several things:
a) There is likely another "junction/splice" (possibly intentional or possibly a short from the melted Black/Yellow wire) somewhere, likely in the under hood headlight harness.
b) This other junction is either a sensor wire (no longer connected) that was "sensing" through the ALT gauge or in the convoluted scheme that Ford used to incorporate this nearly useless gauge, the "charging" was actually going through the ALT gauge!
c) If the charging system and all of it's sensing and monitoing were removed from the harness, all would be well and function for my purposes!
b) This other junction is either a sensor wire (no longer connected) that was "sensing" through the ALT gauge or in the convoluted scheme that Ford used to incorporate this nearly useless gauge, the "charging" was actually going through the ALT gauge!
c) If the charging system and all of it's sensing and monitoing were removed from the harness, all would be well and function for my purposes!
As it is, if I disconnect the alternator, all else seems to function correctly with not any dramatic amperage draw, except no charging while running. I have already, in the past, removed all accessory and auxiliary power from the ignition switch to be powered through a separately fused and powered relay.
From what I can gather, all that should be required is:
A) A nice, heavy #6 or larger wire from the B+ terminal of the 3G to the battery side of the starter solenoid.
B) A #14, or so wire from the "A" terminal of the 3G to a sensing location of my choice. (MAD author http://www.madelectrical.com/index.shtml suggests remote sensing at the point of highest current draw as opposed to sensing at the battery)
C) A short jumper wire from the "S" terminal of the 3G to the small plug on the alternator.
D) A #14 or so wire from the "I" terminal of the 3G to a key on power source.
Please correct me if there is some flaw in my thinking and/or plan.B) A #14, or so wire from the "A" terminal of the 3G to a sensing location of my choice. (MAD author http://www.madelectrical.com/index.shtml suggests remote sensing at the point of highest current draw as opposed to sensing at the battery)
C) A short jumper wire from the "S" terminal of the 3G to the small plug on the alternator.
D) A #14 or so wire from the "I" terminal of the 3G to a key on power source.
Thanks 4 Your Patience,
Gene
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