66furywagon
Well-Known Member
This is what the gauge looks like
With no car running or battery hooked up.
With no car running or battery hooked up.
Charging question
- Thread starter 66furywagon
- Start date
66furywagon
Well-Known Member
Yes the gauge did move when i turned on the lights deep discharge
Since the gauge moved, it probably is not "open" but one way you can test the continuity of the gauge is to disconnect the positive battery cable and span the two terminals on the gauge. Then hook the battery cable back up to see if the car will then charge itself when started. You can do this test with the car's regular wiring hooked to the alternator. Use the voltmeter to verify charge.
Dave
Dave
66furywagon
Well-Known Member
Dave thank u for all your help
66furywagon
Well-Known Member
I will do some testing tomorrow
Thank u
Thank u
Triple Pickle
Senior Member
I’d gamble $20 and put a new regulator on it. Takes about 15 minutes at the most. Install it, start it up and see if the gauge moves to charge.
I’m all for diagnosing the problem and all that, but to me, this is a cheap gamble. And sure beats running test wires,taking the dash apart, etc. If it doesn’t fix it, then you’ve eliminated everything but the wiring.
I’m all for diagnosing the problem and all that, but to me, this is a cheap gamble. And sure beats running test wires,taking the dash apart, etc. If it doesn’t fix it, then you’ve eliminated everything but the wiring.
Story Time
Back in 1978 my ragtop started doing strange things, the ammeter would read funny, the battery kept losing charge and I like you guys started changing parts with the hope of success. Well, new battery, new alternator, new voltage regulator later the problem didn't change. A second alternator, no change. A second voltage regulator, no change. It totally pissed me off and I parked the car in my back yard and it sat until 1997. I put yet another battery in her and some fuel. Crank to fill the float bowl and she started like a champ. However the charging problem remained. I found a wiring diagram I could understand.
I got to thinking, if my battery is good, my alternator and voltage regulator are good, why doesn't my ammeter show charge and why doesn't my battery charge. Looking at the diagram, all the black wiring side seemed to work perfectly. Looking at the red side, the bulkhead connection could be my problem, if this connection is bad, all my problems make sense. Anyhow I was in teardown mode so once the fenders and wheel wells were gone the pesky bulkhead connector became visible. Guess what.
That burned up and melted connector is the connector shown in the diagram in the red circuit. I noted the connector slot beside it was empty, so I moved the circuit over using new connectors from NAPA.
Napa...part number 784490 for male and 784491 for female. The package says GM on it, but they work on Mopars also.
So what about all the bypass the ammeter talk. An ammeter is basically a piece of wire with a short piece of known resistance wire in parallel. The meter itself is really a center zero volt meter that measures the voltage drop across the resistance wire. So, looking at the diagram, if the power is coming from the battery, the meter reads discharge. If the power is coming the alternator and going to the battery, the meter reads charge. About the only things that can go wrong is loose nuts attaching to the wiring to the meter, or most unlikely a broken resistance wire within the meter. In any case the meter, even when it fails, will not cause problems. A very elegant system.
You must however be careful yarding on under dash wiring so that the ammeter nuts stay tight. On my car I used two nuts per stud, one to lock the wire and the second to lock the first nut.
If you decide that the ammeter must go and you want to use a BMF alternator wired directly to the battery, here is another wiring diagram.
Personally I think this is overkill. If you instal a monster alternator, by all means, use the direct to the battery, with a fusible link, wiring to charge the battery. However I would leave the bulkhead connectors and ammeter in place. In either case, if you add monster audio amps, rad fans or other high draw toys, power them directly from the battery, with proper fusing. Do not in any case connect high draw toys to the existing under dash wiring, it is simply not designed for additional loads. Basically it's not a fusing problem, the wire gauges used are just too small for any additional loads.
You have probably noted that everyone seems to promote their best guess solution when it comes to wiring issues. Many suggestions are good, however, many are simply guesses and a surprising number are just crazy. It's the crazy ones that cause car fires.
My advice, study any changes carefully before you make any changes to ensure you understand how everything works before you start cutting wires. If you don't understand something, don't do it until you do.
I hope some of this helps solve your problem.
Back in 1978 my ragtop started doing strange things, the ammeter would read funny, the battery kept losing charge and I like you guys started changing parts with the hope of success. Well, new battery, new alternator, new voltage regulator later the problem didn't change. A second alternator, no change. A second voltage regulator, no change. It totally pissed me off and I parked the car in my back yard and it sat until 1997. I put yet another battery in her and some fuel. Crank to fill the float bowl and she started like a champ. However the charging problem remained. I found a wiring diagram I could understand.
I got to thinking, if my battery is good, my alternator and voltage regulator are good, why doesn't my ammeter show charge and why doesn't my battery charge. Looking at the diagram, all the black wiring side seemed to work perfectly. Looking at the red side, the bulkhead connection could be my problem, if this connection is bad, all my problems make sense. Anyhow I was in teardown mode so once the fenders and wheel wells were gone the pesky bulkhead connector became visible. Guess what.
That burned up and melted connector is the connector shown in the diagram in the red circuit. I noted the connector slot beside it was empty, so I moved the circuit over using new connectors from NAPA.
Napa...part number 784490 for male and 784491 for female. The package says GM on it, but they work on Mopars also.
So what about all the bypass the ammeter talk. An ammeter is basically a piece of wire with a short piece of known resistance wire in parallel. The meter itself is really a center zero volt meter that measures the voltage drop across the resistance wire. So, looking at the diagram, if the power is coming from the battery, the meter reads discharge. If the power is coming the alternator and going to the battery, the meter reads charge. About the only things that can go wrong is loose nuts attaching to the wiring to the meter, or most unlikely a broken resistance wire within the meter. In any case the meter, even when it fails, will not cause problems. A very elegant system.
You must however be careful yarding on under dash wiring so that the ammeter nuts stay tight. On my car I used two nuts per stud, one to lock the wire and the second to lock the first nut.
If you decide that the ammeter must go and you want to use a BMF alternator wired directly to the battery, here is another wiring diagram.
Personally I think this is overkill. If you instal a monster alternator, by all means, use the direct to the battery, with a fusible link, wiring to charge the battery. However I would leave the bulkhead connectors and ammeter in place. In either case, if you add monster audio amps, rad fans or other high draw toys, power them directly from the battery, with proper fusing. Do not in any case connect high draw toys to the existing under dash wiring, it is simply not designed for additional loads. Basically it's not a fusing problem, the wire gauges used are just too small for any additional loads.
You have probably noted that everyone seems to promote their best guess solution when it comes to wiring issues. Many suggestions are good, however, many are simply guesses and a surprising number are just crazy. It's the crazy ones that cause car fires.
My advice, study any changes carefully before you make any changes to ensure you understand how everything works before you start cutting wires. If you don't understand something, don't do it until you do.
I hope some of this helps solve your problem.
66furywagon
Well-Known Member
Ok the wagon is charging now.
It was a bad terminal in the bulkhead.
The main alternator wire.
Gauge works works fine.
Thank u all for the help.
It was a bad terminal in the bulkhead.
The main alternator wire.
Gauge works works fine.
Thank u all for the help.
Last edited:
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