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Charger no charging (still)

74Slant6Charger

74Slant6Charger

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We've had this frankenstein 1974 Charger for a long time.

It is a factory slant six car, but a prior owner crudely swapped in a 318/904 from 1975... The wiring harness is a bit of a gong show, and it has never charged in all my years owning it - making it just sit around and continue rusting in quiet.

We've replaced the Voltage regulator, the Ballast resistor (4-prong), tested the alternator, attended to the grounds, cleaned up the firewall bulkhead connections, and STILL - no charge.

I am so frustrated and I know its hard to diagnose over the internet, but does anyone have any tips for where to look next? Any diagnosis tricks or anything we can try??

thank you guys

74charger.jpg
 
Is the alternator actually putting out 13 to 14 volts while the engine is running? Check your fusible link?
 
When you say "no charge" how are you testing it? Just by the amp gauge or with a test meter?
What is the running voltage?
 
Testing using a meter on the battery terminals... when running it is 10 or so. It gets lower the longer it runs. The ammeter shows 'discharge' when running. Also, when I put a charging pack on the car, when running, the ammeter still shows 'discharging' even though I have the jump pack on it. I thought that was odd. I know my charger jump pack works because it replenishes the batt when i hook it up.
 
74Slant6Charger said:
Testing using a meter on the battery terminals... when running it is 10 or so. It gets lower the longer it runs. The ammeter shows 'discharge' when running. Also, when I put a charging pack on the car, when running, the ammeter still shows 'discharging' even though I have the jump pack on it. I thought that was odd. I know my charger jump pack works because it replenishes the batt when i hook it up.
Click to expand...
maybe you should by-pass the amp meter if it is shorted internal it might make it discharge IF all other wiring and grounds are good . have you ohms tested all wires and grounds ?
 
I was thinking of the bypass trick. Had a '79 Trailduster that I did that to a couple decades ago...

No I haven't ohm-tested all wires and grounds. Wiring is not my strength as you may have guessed.
 
don't just throw parts at it. Get out a test light and meter and start getting some reading.
Must have a fully charge battery to do checks.
Slide04.gif

from 440roadrunner.​
QUICK TEST

For a few quick tests of your charging system, simply buy a meter -- you need one anyway-- and with the engine warm, the battery "normalized" (ammeter centered after some running) and the engine at an RPM to simulate "low to medium cruise" then measure across the battery terminals. What you ideally want is more than 13.5, perfect is 13.8-14, or high end about 14.5. Higher or lower is cause for concern

If this is low, no charge, pull the field wire off at the alternator, and install a clip lead from the output stud on the alternator to the field terminal on the alternator. You should hear the alternator "grunt" and with the engine GENTLY brought up a little in RPM, the battery voltage should start to climb. Be careful not to ref the RPM too much, and monitor battery voltage. Do not rev enough to bring voltage over 15, 15.5.

If you get no output, check the voltage at the alternator stud. Should be close to battery. If you have battery voltage at the stud, but no charging voltage increase, you have something wrong in the alternator

If the voltage at the output stud is low, much lower than battery, you have a wiring problem in the charging/ output circuit, either the ammeter or the bulkhead connector is your no 1 suspects

If this test DOES show a marked voltage increase, you have either a wiring problem in the regulator/ field circuit or a bad regulator.

To check for that, unhook the wires from the regulator, and connect them with a clip lead, reconnect the field wire at the alternator. As above, the alternator should output "full tilt," and be careful of the RPM

If this test shows a charging increase, you need a regulator.
​

http://www.imperialclub.com/Repair/Lit/Master/269/Page03.htm

http://www.classicwinnebagos.com/forum/index.php?topic=3424.0
 
74Slant6Charger said:
I was thinking of the bypass trick. Had a '79 Trailduster that I did that to a couple decades ago...

No I haven't ohm-tested all wires and grounds. Wiring is not my strength as you may have guessed.
Click to expand...
do your self a favor go to you tube and look for some vid's on how to use a multi meter go to harbor fright and buy one if you dont have one and start trying to test one wire at a time lets say from the alt pos post to the bulk head see what reading you get then from the alt pos post to the battery and see what you get. it will take less time to learn than chasing your tail.
 
make sure the VR is actually grounded to the firewall and you have a great battery to body ground.
the MAD BYPASS is something I would HIGHLY recommend. I just got done doing it on my 74. Google for information. bypass the ammeter and bulkhead and add a volt gauge
 
Like you, I too have a Charger that doesn’t charge. My Amp gauge always shows discharge. I’ll be doing the same troubleshooting on it as suggested in this thread. Getting my car on its wheels, running and steerable is first priority though.
 
I have a '73 Charger and have had to replace the voltage regulator a number of times. When I first got it running back in '01 I had to replace the voltage regulator 2 or 3 times as they kept immediately failing (I can't remember what, if anything, I did to fix it). Since then it seems like every few years the voltage regulator fails.
The only real problems I've had with this car have been electrical. Today I'm going to try to figure out a new and mysterious cranks but no fire when hot condition.
Does your car still have the ground cable that goes from the back of the block to the firewall?
Are you sure you have the correct alternator and that it is wired correctly?
 
Last edited:
amm doesn't need to by replaced or bypassed, just mantenienced after all these years of use and even more, abuse.

Electrical stuff is the part everybody minimize, but they are important just like the brakes or fuel lines. When it comes the moment for a good job on this area, it's time to do it. You can't keep the electrical system being patched continuouslly. Specially when it comes to the charging ( and ignition ) system.

please, take your time to remove and check engine harness conditions, bulkhead conditions and headlight harness conditions on red batt wire and check them furtherly. It has been working for 50 years and mostly sure bad used and abused.
 
A engine bay harness is not that expensive and would probably be a smart move even if you do find the issue.

Every time I found a wiring issue under the hood it traced back to a poor connection at the bulkhead connector. I believe in 74 they still routed power to the ammeter via the bulkhead.
 
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