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Sad Cuda.... HELP DIAGNOSE

CudaK

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Sooooo the night before last I decided to do a quick maintance on my 1973 340 Cuda, drained oil,filter and lubed the front end steering parts..... but the hurriedness of the job caused me to forget that I had turned the ignition switch on and that's the way it stayed all night. About 10hrs later and a cars and coffee show to go to.....damn it left the key on last night and the car is stone dead not even a click !!!!

Now I go get my jump box and discover it don't hold a full charge, after several attempts to start it slowly cranks but not enough juice so it's no go. So now I drive across town to where I store my Dart and Challenger and grab my roller battery charger to give it that powerful jump start it needs with a dead battery.
So I get home... hook up the charger and bam sure enough fires right up !!!
Happy I get in and my girlfriend and I go to the show.... now I'm noticing that my stock dash amp meter is pegged +to the right, and thinking WTF now I get to the show a few miles away pop the hood and I don't see any juice coming from the battery vents as I'd had seen before on another vehicle from over charging... hmmm so I check all the connections everything is tight and I go about the day. 4 hours later shows over we drive home, now I notice the amp gauge is not pegged but about 2 o'clock position and the needle its dancing about.... I get home pop the hood look around... nothing " I'm not great at electrical issues " so close the hood and head inside.

About 3 hours later we decide to drive for dinner and grab a coffee before heading home. Car now has started fine, and is running fine. BUT now I notice the amp gauge is dead balls in the middle and not moving....almost like normal. So now It's getting dusk so I flip on the fog lights and don't really notice them on the car in front of me and they must be very dim.... very soon after that I flip on my head lights at the next stop light and I now notice the car starting to run rough and have little to no power so before it stalls I turn lights of and baby it to a parking lot...

I call around to see who's around to pick us up so I can go get a spare Voltage regulator.....the only spare part I have for it at the house thinking maybe this is it sounds like from what I've read in the past could be Voltage reg. . I get home grab the Voltage reg. And tools and head out to the Cuda....
Now the battery seams to be starting the car just fine over and over as after I install the Voltage reg. And put it in gear and there's absolutely no power when under load, it will rev at this point in neutral but no power in gear " wants to die. "

Now it's 9:00pm Sunday no parts store open and they won't have the parts anyhow they never carry older mopar parts. and SO I have no choice but to call my local tow company to come rescue us.... and flat bed my now "Sad Cuda" back to my house with my head hung low.....

Ok here's what I have on my plate now...questions !!!

1) Battery seems fine, and amp gauge is working properly it appears to be.

2) SO did I fry the Ignition module when I jump started it with the battery charger ?

3) Could I have damaged the alternator ?

4) Voltage Regulator no good. " wasn't sure on the spare one"

Is or should my Alternator be a 65 amp unit ? It's a replacement that was installed before I purchased the Cuda... and it's got a double pulley so I know it's not factory.

Thanks for your time, help and comments
 

tonysrt

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Do you have a voltmeter to put across battery terminals with it running? Voltage should be at least 13.5 volts at fast idle. The voltmeter is a necessary tool for electrical problems, unless you have voltmeter in your gauge package. Get a HF cheapie and keep it in the car. It has solved many a problem before pulling out my hair.
 

CudaK

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I do got home today got the multimeter and battery/charging system tester out and found out alternator is completely shot...

Do you think the battery charger jump fried the alternator ?
 

tonysrt

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Maybe after the dead battery, alt. had to overwork to bring battery back up. That's why voltmeter should be in a gauge package with Temp. and oil press..
 

moparleo

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Battery seems fine. Did you slow charge disconnected from the car ? Did you do a load test after discharging the surface charge ? How low did the battery go during the load test ? Less than 9.5 volts ? After testing, is the battery reading 12.5 volts or more ? If not, the battery should be replaced before any other electrical testing. The battery is always the first electrical component to be tested when doing any type of diagnostic work.
 

KATSAAR

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leaving the key on you prob fried the brush wires in the alt.
surprised you didn't damage the voltage regulator also.
if the gauge is jumpy. replace the v regulator.
good luck.
 

CudaK

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I installed

New Alternator
New ignition Ecm
New Voltage regulator

And I bought all new engine harness, headlight pig tail,tranny back up pig tail and firewall junction box.

As all those wires were dry and connections were green.... I'm not taking any chances.
 

74stroker

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I had a short from a bare wire off the alternator in 74 challenger stroker. Replaced engine wiring harness, rallye gauges still malfunctioning: no or intermittent tach, alternator maxes out on charging even at low rpm 2500, gas gauge reads less than correct amount. I have new solid state dash voltage regulator. What is best way to replace it? I've read several posts on how to pull dash out. What do you suggest?
Thanks for any help you can provide.
 

cuda joe

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first charge batt and load test it you need a good batt to start with if batt is iffy replace it.. then when running with cheak volts at batt should be charging at 13.5 -to 15 volts not over not under .. with the gages sounds like a bad ground or loose or bad connection in the wire harness also look for burnt or melted wires best of luck
 
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