Discharging Problem

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64_Barracuda

64_Barracuda

Virginia Beach VA
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I to have a discharging problem when anything like the lights, blower, wipers are turned on. I have read some of the posts so here is my story;
1964 Barracuda 273, 2bbl. A/C, P/S, P/B, Intermittent wiper, radio.

Readings so far, key on, motor off;
Battery 14.1
Alternator B=14.2 Field=11.5
Volt Reg IGN=13 Field=11.9

So reading the schematic it looks as though the Alternator is on the negative side of the AMP Meter and the Voltage Reg IGNITION is on the positive side.

Which seems to be I think that something on the negative side of the AMP meter might be bad? maybe after the spice point?

I will start the old girl up and take the readings again running and then also with a full load of all the accessories.

I am not sure what I am checking when I run a 12 gauge wire from the positive side of the battery to the B side of the Alt, except that it can take a charge and perform inductance to the Field?
 
Some of what you posted is confusing, you say, voltage readings ENGINE OFF

The battery should be no where near 14 v with engine OFF. Should be down around 12.6, after sitting for a bit. Turn headlights on for about 1 minute then take another reading.

FIRST we need to confirm engine off readings.

Read the battery, then read the IGN terminal of the voltage regulator with key ON, engine OFF. There should be not more than .2--.3V (three tenths of one volt) difference

Run the car and check battery running voltage at a good fast idle to simulate "medium cruise." With engine (regulator) warm, voltage should be 13.8--14.2, and in no case below 13.5 or above 14.5

If this is so, load the system, turn on heater, lights, etc, all the accessories you can.

Now re--check battery running voltage --under load--medium cruise--, AND check charging voltage at the alternator battery stud.

These two points will now tell you if you are losing voltage "in the harness" or if the alternator simply cannot put out enough.

If there is nor more than say, 1 volt difference, you are in the ballpark, and if this voltage drops under load, your alternator has a problem, such as one or two bad diodes, etc.
 
Ok looks like I had a bad meter.

Readings
Engine off Key on
Batt 13 IGN 12.6

Running Fast Idle
Batt 14.2

Loaded
Batt 15.5 ALT 14.2 IGN 15.7 AMMETER at 3/4 Charge side.

Running loaded or unloaded at idle
Batt 12.4 ALT 12.4 IGN 10

IGNITION seems to be all over the place each time I take a reading.

You spoke about putting Battery positive jumper to output of ALT, what exactly is this doing?

Thanks again for all the help.
 
Your readings still don't make much sense...............which might indicate improper (bad) connections to the meter, or maybe a bad connection in the harness

There are several areas of concern

Not sure, but I believe?? that the main ammeter wires on the 64 go through the bulkhead in separate connections from the bulkhead. But check those anyway

Check the connections to the ammeter, and monitor the rear of the ammeter after running for a bit for heating, showing bad connections there

1---the alternator may be giving up, a combo, maybe, of worn brushes, sticky or greasy brushes, or blown diodes or other problems which diminish it's full current output

2--regulator / field wiring problems. This includes a poor ground at the regulator, dirty contacts if the regulator is still the old mechanical relay type, and voltage drop in the harness feeding the regulator voltage. This is the "ign run" buss, or what Ma calls "IGN1". Same point that feeds the ignition switch side of the ballast resistor.

also in this realm are bad connections in the ignition harness path from the battery to the regulator. On newer cars this is battery--fuse link--bulkhead connector--ammeter--in harness splice--ignition switch connector--through the switch--back out the switch connector (dark blue "ignition run"--back through the bulkhead--to the ballast resistor and to the regulator IGN terminal.

3--Bad connections in the path from the alternator to the battery. In newer cars this path is battery--fuse link--bulkhead connector--ammeter--"in harness splice"--bulkhead connector--to alternator. This, mainly, is what you are trying to eliminate by hooking a large gauge bypass wire from alternator to the start relay.

The DIFFERENCES in the above description MAY be that your 64 (I believe) has the two large battery/ alternator charge wires separated from the bulkhead

Here's a very good read:

http://www.madelectrical.com/electricaltech/amp-gauges.shtml

So harness problems are almost always CONNECTION problems, so this includes wire ends (crimped connectors) in the connectors, as well as ring terminals at the alternator and ammeter

Believe it or not, the "in harness splice" can and has failed. A few members right on here have had this dilemma. This splice is in the black ammeter wire a few inches from the ammeter, taped up in the under--dash harness. Only way to check it for certain is to pull the cluster, access the harness, and untape or cut the tape from the black ammeter wire down until you find the splice

This splice feeds the hot fuse panel buss, the ignition switch input, the headlight power to the headlight switch, and a coupe of other things on some cars. NONE of this is FUSED!!!
 
It might be easier to attempt to determine if the alternator is capable of outputting what you need. To do that, Get the battery "up and normal" and unhook the green field wire to the alternator. Run the engine at "medium cruise" with all accessories, lights, on, and jumper a clip lead from a battery source directly to the alternator field terminal.

The alternator should be able to AT LEAST output 14V, and monitor the voltage so that it does not go above 15, by adjusting engine speed

Check both the battery and the alternator stud for voltage, and check these carefully. If you have more than a volt or so difference, you have problems in the charging wire path to the battery

If this voltage will NOT come up under load, IE sags below 13.5, your alternator is done

If you DO get a different alternator, get yourself a mid--70's "square back" which has TWO field connections. You can use your early regulator by merely grounding either one of the two field connections, or you can convert to the 70/ later regulator by adding one more wire.
 

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Well the current meter I am using is good. The Bulkhead connecter has both ammeter wires going through the bulk head connectors. My 65 is different they have there own lug on the bulkhead for positive and negative.

The other thing is my harness is pretty brittle, so just because I have good continuity and voltage doesn't mean I don't have enough to hold current. I may start unwrapping the harness for the Alternator first.
 
Ok, I read you said in another post to run a jumper wire from the positive batter to the output battery of the alternator. should I do this? what does this test?
 
64_Barracuda said:
Ok, I read you said in another post to run a jumper wire from the positive batter to the output battery of the alternator. should I do this? what does this test?
Click to expand...

Item 3 in post no4 above, especially if the voltages between battery and alternator post differ by more than about a volt UNDER HARD CHARGING
 
I have a gasious discharge after eatin tacos.
 
RustyRatRod said:
I have a gasious discharge after eatin tacos.
Click to expand...

When I read the headline I thought "somebody needs to visit the Doctor" LOL
Glad you got it fixed. 67Dart273 is like "Reddy Kilowatt" He gets all juiced up about Mopar electricity ! lol
 

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REDDY KILOWATT!!!!!!

haven't heard of 'im in YEARS!!! "He" used to be an icon of one of the local power companies in my small home town, but for the life of me, I can't remember which one

We had "Northern Lights" which I guess is a relatively small rural power co. (power co-op)

We had "Pacific Power and Light" which serviced my house
 
67Dart273 said:
REDDY KILOWATT!!!!!!

haven't heard of 'im in YEARS!!! "He" used to be an icon of one of the local power companies in my small home town, but for the life of me, I can't remember which one

We had "Northern Lights" which I guess is a relatively small rural power co. (power co-op)

We had "Pacific Power and Light" which serviced my house
Click to expand...

LOL He's got his own website for crying out loud. I'm impressed.

http://www.reddykilowatt.org/
 
I stole Reddy to make a sticker for my rat truck.
 
67Dart273 said:
Not sure, but I believe?? that the main ammeter wires on the 64 go through the bulkhead in separate connections from the bulkhead.
Click to expand...
63 & 65 were the only years with the separate "buss lugs" for the big ALT and BATT wires in the bulkhead connector. That is why I am putting a 65 bulkhead in my 64 (requires 1/4" wider). 63 was different in that one of the 2 connectors was about half width (fewer terminals). I think that all bodies in 65 had the "buss lugs", at least my Newport does, as does the Fury harness I got to upgrade my 64. It is nice to not melt the bulkhead terminals (my 64's are slightly melted).

I am guessing they dropped the buss lugs because it took longer assembly time. My guess is that they brought it back in 65 because they needed some of the terminals for new accessories. In 66 they went to a 3-connector bulkhead and had more space, so put the big wires back on the "56 terminals". If they had reports of melted connectors then, they probably figured "our customers buy a new car every 3 years anyway, we don't care about 2nd owners".
 
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