Ammeter pegged...
- Thread starter 7milesout
- Start date
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Hey guys - It's been a while since I've worked on this problem because I had to deal with a radiator leak. The radiator is all good now. So I'm back on this.
I took El Scampo to a dragstrip on 3/29, Friday night. The insulation tape on the fuel line wasn't enough, I'm still getting vapor lock. Which is beside the point, but I'm chasing that down too. Resisting getting a low pressure electric pump. Anywho...
What I wanted to say was, on the way down there, and most of the ride home, this thing acted completely normal, voltage wise. That is, until about a 10 second span of time on the way back. Just toodling along at 55 mph, at about 11 pm, and all of the sudden, all the lights that were already on (headlights, dash lights, etc) lit up like Hiroshima. A quick glance at the ammeter, and it's pegged to the right (charging). I thought about what I could do to add electrical drag so in order to bleed away some of the amperage from all the lights. I can't recall what I did off hand, but I turned on something. Not much help I'm sure. I was about to pull over and shut it off, when it just went back to normal, and that was that. It lasted right about 10 seconds.
It didn't happen again. At other times, even when the ammeter is pegged, the ammeter very much responds to rpm. Even when pegged, if I let the RPM drop to idle, the gauge goes almost to the neutral point.
So, just wanted to see more about what you guys think about this issue. Now I'm going to go back and read this whole thread again.
7milesout
I took El Scampo to a dragstrip on 3/29, Friday night. The insulation tape on the fuel line wasn't enough, I'm still getting vapor lock. Which is beside the point, but I'm chasing that down too. Resisting getting a low pressure electric pump. Anywho...
What I wanted to say was, on the way down there, and most of the ride home, this thing acted completely normal, voltage wise. That is, until about a 10 second span of time on the way back. Just toodling along at 55 mph, at about 11 pm, and all of the sudden, all the lights that were already on (headlights, dash lights, etc) lit up like Hiroshima. A quick glance at the ammeter, and it's pegged to the right (charging). I thought about what I could do to add electrical drag so in order to bleed away some of the amperage from all the lights. I can't recall what I did off hand, but I turned on something. Not much help I'm sure. I was about to pull over and shut it off, when it just went back to normal, and that was that. It lasted right about 10 seconds.
It didn't happen again. At other times, even when the ammeter is pegged, the ammeter very much responds to rpm. Even when pegged, if I let the RPM drop to idle, the gauge goes almost to the neutral point.
So, just wanted to see more about what you guys think about this issue. Now I'm going to go back and read this whole thread again.
7milesout
67Dart273
Well-Known Member
You should not even be running it AT ALL with the charging system acting up......you can blow things up on the car, meaning, failed electronics from over--voltage
ONE THING YOU can try.........Pull that regulator off and SCRAPE around the bolt holes on the body and the rear and front of the VR and remount with star lock washers. THAT REGULATOR MUST BE GROUNDED
If you want to race it..........I would not street drive it.........you can charge the battery, disconnect the VR connector and run without a charging system. At least that way it won't hurt anything until you get it fixed
Isn't the battery boiling and puking? I bet it is!!!!
ONE THING YOU can try.........Pull that regulator off and SCRAPE around the bolt holes on the body and the rear and front of the VR and remount with star lock washers. THAT REGULATOR MUST BE GROUNDED
If you want to race it..........I would not street drive it.........you can charge the battery, disconnect the VR connector and run without a charging system. At least that way it won't hurt anything until you get it fixed
Isn't the battery boiling and puking? I bet it is!!!!
67Dart273
Well-Known Member
Where are you located? PTC doesn't compute. If you can get set up with a voltmeter you could call me sometime and I can direct you through a few checks. I'm in the N end of Idaho. Pacific Daylight time. I work We-Th-Fri
The battery seems fine. No pukage, lots of startage. Looks nice and clean. PTC = Peachtree City, GA.
You and me and everyone else too! LOL
Since it showed roughly 40 amps charging, the regulator must be grounded. If it wasn't, then power could not flow through rotor unless the green wire is shorting.
Look carefully at the green wire from the alternator field terminal to the regulator. If that terminal or wire has poor insulation and can touch ground, that's one possibility.
Another possibility is an internal failure in that P-part regulator.
Last, but not least, is a poor connection with the blue wire at the regulator or where-ever its spliced in. The rest of the blue wire (after the splic)e must be good or the rotor would not have had recieved much if any power.
Lets make sense of the items mentioned; Blue wire, Green Wire, Field.
Field is shorthand for electro-magnetic field.
Blue Wire is the power source for the field and has a branch to tell the voltage regulator whether voltage is going higher or lower than the set point.
Green Wire connects the field to ground through the voltage regulator. If a stronger field is needed, the regulator connects the green wire directly to ground.
If a weaker field is needed, it opens the circuit. There's also an in between connection through some form of resistance.
The rotor windings create the electromagnetic field.
The Field terminals connect to brushes. (orange arrows)
Field is shorthand for electro-magnetic field.
Blue Wire is the power source for the field and has a branch to tell the voltage regulator whether voltage is going higher or lower than the set point.
Green Wire connects the field to ground through the voltage regulator. If a stronger field is needed, the regulator connects the green wire directly to ground.
If a weaker field is needed, it opens the circuit. There's also an in between connection through some form of resistance.
The rotor windings create the electromagnetic field.
The Field terminals connect to brushes. (orange arrows)
Any chance you can swap out the regulator with a known good one? Its the job of the regulator to regulate the voltage from the alt and thats not happening.
67Dart273
Well-Known Member
^^There are a few possibilities here^^
The old "voltage drop" either in ground circuit or harness..............
Bad VR but this is actually rare, they actually usually fail completely
Bad battery
The old "voltage drop" either in ground circuit or harness..............
Bad VR but this is actually rare, they actually usually fail completely
Bad battery
I reread the whole thing including the attachments. The whole MAD - Amp gauge wiring fixing approach sounds like the absolute best way to go.
But for a NON electrical guy, it also sounds like the scariest thing to me to actually achieve. All because I generally fry a handful of fuses before I ever get anything right. It's really annoying and a motivation killer to be some dumb about what electrons actually do, versus what I think they should do.
Tonight, if I get the chance, I'm going to put my multimeter on the battery and alternator as was mentioned in the early part of this thread, and get back with you guys on what I see. However, El Scampo is bound to not foul up whilst I have the multimeter on it. I'll also check the wiring to / from the VR, as well as pull it off, check / clean all the connections.
As far as the MAD fix … where is the starter relay? My mind says there would be a fuse box under the hood somewhere (as well as the one under the dash). I'm fairly certain that the starter relay and the starter solenoid are 2 different things. As I understand it, the starter solenoid is an electrical device that is attached to the starter and is a trigger. It uses small wiring and a small current signal to magnetically pull contacts. Said contacts are large and close the circuit from the battery to the starter (and then to ground), so that big amperage can flow through the starter, but small amperage is used at the starter activation switch.
I don't know, maybe a starter relay might be one in the same thing, just not located on the actual starter. I hope it's not on the starter, as when I decided to install (TTi) headers, I removed the factory starter and used the small starter (I forget the name of it). And I think trying to access that small starter now with the headers on is going to be a beeatch.
7milesout
But for a NON electrical guy, it also sounds like the scariest thing to me to actually achieve. All because I generally fry a handful of fuses before I ever get anything right. It's really annoying and a motivation killer to be some dumb about what electrons actually do, versus what I think they should do.
Tonight, if I get the chance, I'm going to put my multimeter on the battery and alternator as was mentioned in the early part of this thread, and get back with you guys on what I see. However, El Scampo is bound to not foul up whilst I have the multimeter on it. I'll also check the wiring to / from the VR, as well as pull it off, check / clean all the connections.
As far as the MAD fix … where is the starter relay? My mind says there would be a fuse box under the hood somewhere (as well as the one under the dash). I'm fairly certain that the starter relay and the starter solenoid are 2 different things. As I understand it, the starter solenoid is an electrical device that is attached to the starter and is a trigger. It uses small wiring and a small current signal to magnetically pull contacts. Said contacts are large and close the circuit from the battery to the starter (and then to ground), so that big amperage can flow through the starter, but small amperage is used at the starter activation switch.
I don't know, maybe a starter relay might be one in the same thing, just not located on the actual starter. I hope it's not on the starter, as when I decided to install (TTi) headers, I removed the factory starter and used the small starter (I forget the name of it). And I think trying to access that small starter now with the headers on is going to be a beeatch.
7milesout
I had a similar issue on my 72 Satellite. The ammeter would peg and the lights would get very bright. Sometimes it would be OK. For me, it turned out to be the voltage regulator however I would follow the advice given here to troubleshoot. I would also agree and be very careful with that situation and not drive the car until fixed.
In my case the battery started to bulge and the bulbs got very hot. I got lucky.
I also keep spare VR, ballast resistor and a spare alternator in the trunk.
Good luck and keep us posted.
In my case the battery started to bulge and the bulbs got very hot. I got lucky.
I also keep spare VR, ballast resistor and a spare alternator in the trunk.
Good luck and keep us posted.
MAD's bypass has flaws too. Besides its not a fix. The ammeter is telling you something on the battery side of its circuit is drawing current big time, although not all the time. Instead of hacking up something you're not familiar, my advice is find the problem and fix it. I had 3 P-part voltage regulators fail, and a several Standard VR-128 flake out like your seeing. However, that's a different type of VR, it controls the positive side. So I don't know if your p-part VR might flake the same way or not, but I wouldn't discount it.
So far we have four possible causes we've come up with. It's probably one of them.
So far we have four possible causes we've come up with. It's probably one of them.
Mattax - I agree with you 100%. So I will resolve the root cause of the problem. I got to messing around with El Scampo last night and I measured the battery with the engine off (12.7 V IIRC … I should have took a picture because I'm just guessing at what I remember). Then I moved on to look at how I was going to measure the alternator output after firing it up.
And I found the below. My mind thought "AHAAAAA." The smoking gun. So I took pictures and figured I would show you guys before moving on. And then I went on and worked on another vehicle. However, later on about bed time I got to thinking. That damaged connection could be either the cause … OR A SYMPTOM.
My request is: Please confirm if you think this damaged connection is the cause, or that it could be either the cause or a symptom. I will need to fix it either way, and then move on from there.
Back side of the alternator...
And I found the below. My mind thought "AHAAAAA." The smoking gun. So I took pictures and figured I would show you guys before moving on. And then I went on and worked on another vehicle. However, later on about bed time I got to thinking. That damaged connection could be either the cause … OR A SYMPTOM.
My request is: Please confirm if you think this damaged connection is the cause, or that it could be either the cause or a symptom. I will need to fix it either way, and then move on from there.
Back side of the alternator...
I also took pictures of the VR. It looks clean and pretty. But that doesn't mean it's working right all the time.
However, big question for me. After seeing pictures in various links you guys have posted, I was expecting a ground wire. But, as you can see in the picture, no ground wires.
I had already disconnected it prior to the picture. Just the one connection, that's all.
7milesout
However, big question for me. After seeing pictures in various links you guys have posted, I was expecting a ground wire. But, as you can see in the picture, no ground wires.
I had already disconnected it prior to the picture. Just the one connection, that's all.
7milesout
And lastly, I took pictures of what I believe to be the resistor ballast. Mentioned earlier in the thread, and I didn't know what it was.
Them there wars ain't lookin' too healthy. And one of the connectors is just dangling. Which leads me to believe that this is not the original resistor ballast.
7milesout
Them there wars ain't lookin' too healthy. And one of the connectors is just dangling. Which leads me to believe that this is not the original resistor ballast.
7milesout
It grounds through the case. I would remove the paint from around the bolt holes The bolts need to make contact with the regulator case and ground to the firewall. Don't ask me how I know that a poorly grounded regulator can cause overcharging.
That wiring is nasty and that's only what you can see.
Without seeing the terminal connection, I don't know. My guess is that the wire connection was poor, maybe for mechanical reasons, and then at times of high current flow, it cooked itself good.
If the wire isn't corroding badly you can clean it and crimp on a new ring terminal. looks like that protective ring was molded on? Best you can do is use shrink tubing to proect the crimps, and a seperate insulating ring which Chrysler used on many years.
Is the alternator's output stud tight? If not, you'll have to open the alternator case and tighten it. (Yellow arrow in photo above.)
Yep. Who knows whats melted and shorting to what within the harness, under tape. Some models have a white engine harness connector near firewall, right valve cover, blower motor area. It could be melted and shorting also. In fact it could have been the original fault.
Come and go short circuits are possible where temperature changes, vibration, and distorting plastics are present.
Not to be mean spirited but too bad these photos weren't posted back on Feb 25th. on page 1. The diagnosis would be a bit different.
The Ballast regulates power through the ignition coil.
On your '72, it would have had a second resistor to limit power through the ignition amplifier box (ECU).
Both of those are resistors are bypassed during startup.
The ballast was also a convient location to connect things up.
My suggestion is to cut or unwrap the harness tape and see how far back the wires have insualtion damage.
Then look at the conductor condition. If its all oxidized under the insulation, IMO it should be replaced. If its clean, then cut off the terminals, and slip some heat shrink tubing over the conductor wire to act as new insulation. You can buy various types. I would look at the fuel resistant types and higher temp rating so it doesn't get brittle. You can then mark them with short lengths of colored heat shrink tubing. IIRC the colored stuff is not available in the high temp ratings. Just check out McMaster for a good sense of what is available.
You'll need a good crimper and a some Packard 58 open barrel terminals to replace the ends.
Just a tidbit of possibly related info. A couple days ago I opened up my engine harness because the "blue" wire was melted inside of it. I found the burnt section ended prior to any real damage, but the cause was that the previous owner had installed an aftermarket carburetor and left the electric choke lead (I think) hanging free. Without a shielding cover. It grounded on the intake and melted the wire right back to the ballast resistor. I'm sure when it happened to him the ammeter was acting up and showing some info as well. I am not aware as I have disconnected it.
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