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Ughh... I need.... help. Midlife...

70_Fastback

70_Fastback

Hell Bent for Speed
Follow up to my alternator issue.

I installed a brand new 100-A alternator and a new Borg-Warner voltage regulator (read $40!) last night. Adjusted everything, plugged everything back in. Fired it up. And it's not charging. The BAT post on the alt reads the same voltage as the battery.

If I unplug the 4 prong plug from the voltage regulator and jumper the "A" & "F" terminals it charges like it should 14.x volts.

I tried the other new voltage regulator that was on there and it does the same thing. I'm at a bit of a loss here.

Sluggo mentioned on the phone last night that there could be an issue because my original gauge cluster had an amp meter on it and I converted to all new autometer gauges and installed a voltmeter. So the printed circuit plug is not connected to anything and maybe a circuit is broke there due to not being plugged in for the original amp meter... ?

And also, something a bit different on my car, I grounded the engine block straight to the NEG battery terminal in lieu of to chassis. And I also have a chassis ground - from the fender apron to the NEG terminal of the battery also. Could this be causing any issue...? I don't see how, but thought I would mention it.

If you have time, and it's easier to call, I'll message you my #. If you want to that is.
 
No, it's externally regulated. And the voltmeter should not matter. it's wired seperate and just needs a switched 12V source to read the voltage.
 
"70_Fastback" said:
Follow up to my alternator issue.

I installed a brand new 100-A alternator and a new Borg-Warner voltage regulator (read $40!) last night. Adjusted everything, plugged everything back in. Fired it up. And it's not charging. The BAT post on the alt reads the same voltage as the battery. The two readings should match, but I suspect what you meant is that it is reading 12.5V or so.

If I unplug the 4 prong plug from the voltage regulator and jumper the "A" & "F" terminals it charges like it should 14.x volts.Good!

I tried the other new voltage regulator that was on there and it does the same thing. I'm at a bit of a loss here.

Sluggo mentioned on the phone last night that there could be an issue because my original gauge cluster had an amp meter on it and I converted to all new autometer gauges and installed a voltmeter. So the printed circuit plug is not connected to anything and maybe a circuit is broke there due to not being plugged in for the original amp meter... ?If you originally had an ammeter, you have wires carrying the signal through the light underhood harness (for 1969) or the extended underdash harness (for 1970) that connect to the underdash harness, and then eventually to the dash cluster. What has been done with those wires? They are directly tied to the alternator/battery line.

And also, something a bit different on my car, I grounded the engine block straight to the NEG battery terminal in lieu of to chassis. And I also have a chassis ground - from the fender apron to the NEG terminal of the battery also. Could this be causing any issue...? I don't see how, but thought I would mention it.With all the bondo you have on the car, I'm hesitant to say this is OK. Just Kidding!

If you have time, and it's easier to call, I'll message you my #. If you want to that is. I'll call after my lunch is over.
Click to expand...
 
If you originally had an ammeter, you have wires carrying the signal through the light underhood harness (for 1969) or the gauge harness (for 1970) that connect to the underdash harness, and then eventually to the dash cluster. What has been done with those wires? They are directly tied to the alternator/battery line.
Click to expand...

The printed circuit board plug is just unplugged and left behind the dash, I did cut loose a few of the wires and reused them to feed dash lights, gas guage etc
 
"70_Fastback" said:
The printed circuit board plug is just unplugged and left behind the dash, I did cut loose a few of the wires and reused them to feed dash lights, gas guage etc
Click to expand...

Ruh Roh...you have lines that are always hot and unfused laying around back there! I'd hate to see an overcooked pumpkin...I'll call in a few minutes.
 
"Fast68back" said:
Ahh, the mind of our Gov't employees...
Click to expand...

3 hours and four martinis later....

Jeremy doesn't sound much like his picture, but more like his "cousin" Aaron. You'd think that Mr. American BadAss would have a manly voice...it's more like a high pitched squeal. :bird

I did find out some interesting clues:
(1) The VR is not well grounded as one needs to remove paint behind one of the retaining screws. The VR needs to be grounded to the chassis for it to work well.
(2) The more interesting factoid is that the alternator does not have a grounding wire attached! Aaron...errr..Jeremy said the Sluggo said he didn't have a ground wire on his. Well, lemme tell ya...this is essential for the alternator to work well! If you don't, the ground goes through the case to the engine block, and the case to engine block is not a solid connector. Some cars may get away with it, but that is not recommended.

He'll change these two things, and we'll go from there. If I'm good, the Great Pumpkin may work after all...
 
Did both things and still no luck.

I'm getting beyond frustrated. This F'ing thing should work. It works when I full field jumper the VR (A+F) plug. I think it's these new damn electronic regulators.
 
"silverblueBP" said:
Return that POS and get a one wire alt.
Click to expand...

That makes trouble-shooting more problematic, as you need to blip the RPM's to energize the alternator. And if blipping doesn't work, then what?

Tonite, I'll examine the '70 charging system wiring, to see if there's something unusual in the design...
 
"70_Fastback" said:
Did both things and still no luck.

I'm getting beyond frustrated. This F'ing thing should work. It works when I full field jumper the VR (A+F) plug. I think it's these new damn electronic regulators.
Click to expand...

OK...did some research. There's two different versions of charging systems, depending upon whether you have a ammeter or a tach. Since Jeremy stated he taped the ammeter wires on the now unused dash cluster connector, I'll presume he has the non-tach wiring system.

The VR plug should have three contiguous lines filled: Orange (35), Green/Red (904...this could be violet!), and Green/Black (152). This particular system also has a Black/Red wire connecting the negative (or ground) from the alternator directly to the VR case, and should be part of that harness. (The tach version is grounded via the chassis...kinda strange, don't you think, that Ford isn't consistent?). There should be three wires at the alternator: Orange (F or Field), Black (38 for BATT), and black/red (ground for GND or -). Normally, the black/red wire is tied to the engine block ground as well. The black/red is not part of the covered grommet.

If the VR plug has all four lines filled, there's a real problem here with incompatible wiring. This version should have an additional line at the alternator connector grommet. This line is white/black.

Based upon what Jeremy said, that jumping A to F (green/black to orange) produces 14.5 V, and plugging the connector into the VR only produces 12.5 when the engine is runnng, that strongly suggests that the VR is bad. He said he tried both VR's, but I suspect both are bad at this point.

Jeremy also said his starter solenoid switch was relocated further down on the fender apron, which suggests to me that someone may had to have cut or spliced extra length of wires to make the existing harnesses fit. I would look at that area very closely as well. Somewhere near the alternator or voltage regulator should be a two prong blue plug. The green/black wire from the VR ties to the battery there, and also to the black wire at the alternator.

Here's my suggestion: take a jumper wire from the alternator ground point to the VR case and try again the measurements. I would then beg, borrow, steal, or buy yet another VR (from a different source: I highly recommend Motorcraft solid state), and try again. If that doesn't work, then the next step is to measure the continuity of all the various wires and see if there is some anomalous resistance somewhere in the wiring...

Jeremy knows my number, and has told me he'll call tomorrow.
 
"Midlife" said:
That makes trouble-shooting more problematic, as you need to blip the RPM's to energize the alternator. And if blipping doesn't work, then what?

Tonite, I'll examine the '70 charging system wiring, to see if there's something unusual in the design...
Click to expand...

You are correct, actually I was just bustin his chops. There's no winky emoticon.....

; ^ )
 
Well, we think we finally found the problem, after a couple of hours of long-distance trouble-shooting. First, I want to thank Jeremy for his cooperation, and anticipation of what I would be asking him to do. He had checked continuity of all of his wiring and pulled back the wiring looms to examine each wire: Perfect!

Since the alternator charged the battery when jumpering the A to F terminals on the VR plug, that led us to suspect the VR. He had used 3 different VR's, and they all responded the same. Hmmm... What about that third wire, a green/red wire? No voltage there. We traced it back to the harness plug (no voltage) and to the fusebox (no voltage). It turns out its the power source for everything on that fuse: throttle modulator, pink resistor wire, and a large female bullet plug beyond the firewall that I believe is for some sort of emissions control. Jeremy said he cut the pink resistor wire to plug into his electronic ignition, but without power to the pink wire, it shouldn't run.

It turns out he cut a pinkish colored wire between the ignition switch and the harness plug; on the other side of the harness plug is the green/red wire. Y'all should remember (I failed to do so!) that this is the only wire that is hot in RUN position but not in ACC position. It turns into the pink resistor wire to feed the coil (now bypassed in Jeremy's pumpkin), but also energizes the VR to do its thing.

Last time I talked to Jeremy, he's going to re-energize that wire and see if his car will now charge the battery. When it does, he'll clean up the mess we made, and make everything pretty.

Wow! This was a lot of work. I learned a lot in the process, as did Jeremy. It was a load of fun as well...thanks, Bud! You owe me a Wattles.
 
Yes, that was the problem. It charges great now. So many thanks Randy. PM me your address and I'll have some wattles sent to you :bow
 
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