High Alternator Reading Question:

[Captain D]

HI all,

I've been reading through some older posts regarding the alternator/voltage regulator and I would greatly appreciate your knowledge and experience on this board regarding a question that I have on this subject if I may ask please:

Basically, I have a basic 69' Charger (383 4bbrl), but with a 75 amp alternator as pictured below:

http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_chrysler-square-back-alternator-75-amp-chrome-powermaster_19210106-p?searchTerm=75+amp+alternator

And, for the voltage regulator, a new 60 amp from NAPA that I installed a few months ago in the fall (the closest that we could find to accommodate this size alternator for $75.00). And, finally, an electronic points ignition system.

My question going into this is - I don't know if it has to do with the cold weather since I noticed this issue when the weather got really cold (average 30 degrees for the high temps these past few months), but when I start the car from a cold start and give it that occasional rev up, the alternator gauge needle will quickly jump all the way over to the right when I give it that occasional rev up and goes back to normal when I left off the gas from that occasional rev up. However, when I don't rev it up, or when I am driving the car at a normal cruise, it seems fine at a reading between 0+ to 12+. I apologize if this is a dumb question to ask, but is this normal for the needle to quickly jump way over to the right when the engine is being occasionally revved up at idle and go back to normal when not giving it that quick rev?

Other than that, the only other thing that I've done recently 'electrical' is to paint the horn relay a little to freshen it up (which a connector runs from it to the alternator), install new positive and negative battery connector terminals pictured below, and one spade/Quick-Connector on just the positive side for a CD player, also pictured below:

http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_top-post-battery-terminal-coated-autocraft_6283136-p?searchTerm=battery+terminals

http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_x_25984887-P_x_x?cm_mmc=ACQ-_-Google-_-enhancedRM-_-25984887&ci_src=17588969&ci_sku=25984887&ci_gpa=pla&ci_kw={keyword}&gclid=CJunv5qj67UCFZE-Mgod-HMAOQ#utm_source=acq&utm_medium=google&utm_campaign=enhancedrm&utm_content=25984887

'Thank you' for taking the time to help and I look forward to any and all feedback. It seems like one thing after the next in trying to get it all done before the spring shows...
Best regards,
Aaron

[John_Kunkel]

If the battery is weak or there is something discharging it overnight it's fairly common for the ammeter to show a full charge rate right after startup but if it still does it after a good warmup and driving for a few miles that's not good.

First, have the battery tested...if it tests good and it still charges max after warmup there's a problem. Way too many possibilities to take a guess without more info/testing.

[b5blue]

John is right Aaron, also a battery is effected by cold as the chemical reaction is reduced. (Many times a battery that is borderline here in FL. will die with a first cold snap.) What your seeing is an increase in output as the alternator spins faster from you revving, FASTER=Ability to make more Amps. The REASON is it's trying to recharge the battery. That vintage ALT. only outputs 15-20 Amps @ idle so it's to be expected. (The key is: "@ idle output") Search topics in electrical for: Denso 120 amp  for how I fixed the @ idle charging problem. b5 

[Captain D]

Thank you gents for taking the time to reply to this issue - I greatly appreciate your input,

From what I've gathered from all of these responses collectively at first glance, it would seem that something is draining my battery (from a combination of both the cold weather and an accessory) - hence the alternator having to compensate for the difference. I'm trying to recall anything and everything that I've been working on to what could possibly be draining the battery, perhaps.

With the exception of my installing a new vacuum canister + hoses (not that this is electrical), the only other thing that is different was the 12V 'Quick Connect' to the positive battery terminal:

http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_x_25984887-P_x_x?cm_mmc=ACQ-_-Google-_-enhancedRM-_-25984887&ci_src=17588969&ci_sku=25984887&ci_gpa=pla&ci_kw={keyword}&gclid=CJunv5qj67UCFZE-Mgod-HMAOQ#utm_source=acq&utm_medium=google&utm_campaign=enhancedrm&utm_content=25984887

From this point, we have a CD player as an accessory wire connected to this battery mount. Until I get a multimeter to better test the battery, I'm tempted to remove this mount altogether to see if it makes a difference - especially since I read on here that another member here noted that, "accessories must be sourced always from the alternator."

I also read that there are other things to check, such as: bulkhead connectors, starter relay stud, battery ends clean, etc. but all of these are clean and checked out. So, maybe one of the first things that I'll do is remove this 'Quick Connect' mount. I'm also wondering about the fuses - when they installed both my CD player + CB radio they utilized power through the fuse box. Since I'm not as knowledgeable about this topic as I'd like to be I wonder if this was a factor too. But, I would think that by disconnecting the 12V Quick Connect connection it may eliminate any problems in this area regarding the CD player/CB (if this is the source of the problem, that is). Tomorrow, I'll run through to make sure that I've got good grounds on everything.

Like John and B5 mentioned above, "ammeter to show a full charge rate right after start-up" is exactly what happens when I step on the gas at idle. And, this is also true when he stated, "but if it still does it after a good warm-up and driving for a few miles that's not good." This is exactly what happened as well when I occasionally stepped on the gas at idle after a quick run I did the other day with the car.

I'll keep in touch with any info, but if there are any more suggestions I'm all ears and welcome any and all input,
Best regards,
Aaron

[b5blue]

  Aaron remove the battery and have it slow charged to full and then tested, many parts stores do this for free. (You'll leave it overnight in most cases.) If it verify s at 13+ volts then you can start from there. (Your system and battery really run around 13.5 to 14.5 volts to allow voltage drop through wire.) If the battery fails then that's your issue and the ALT gauge is working and told you something was not right.
  You can get a cheap volt meter at Harbor Freight (Free with a coupon and 10.00 purchase.) or Walmart for less than 10 bucks. If the battery is OK what you would do to check for a drain is disconnect power to clocks or memory functions like the CD player and if the dome light is working off the door jamb switches have the doors closed and of course have every thing turned off. Have the battery installed with the ground wire only and put the meter leads: one on the positive post and the other on the main positive battery cable head. (The thing that attaches the red cable to the battery.)  Be careful that nothing else touches the positive cable or positive battery post by placing clean rags under or around exposed things like the positive cable head. You should get a "0" reading with the key off and removed. 

[Captain D]

HI Neal,

'Thank you' for the info - I'll be sure to make some phone calls and see what I can find out,  . One thing that I did forget to add (not sure if this is relevant or not), but when I put the key in and turn it to the 'on' position (not turning the engine over), the alternator reading goes slightly into the left/negative reading prior to initial start-up.

In the meantime, I was thinking that if I were to start the car to check to see if the voltage regulator got overly warm would anyone feel that it would be best not to actually start the car until I begin to get this squared away?  

Anyhow, I'll keep in touch and thank you again for the helpful guidance,
Aaron

[Nacho-RT74]

you know what ?

I'm remember now I got a similar problem on my car long time ago and it was the stator and rotor being shorted out a while spining!!!!...

More specific, the rear fan blades making a slight contact with the stator lead wires going to the diodes bank!!!

I wasn't really able to get charge ( amperage load ) really no matter the ammeter reading ( also full to charge side when reving up ), but got to read up to 24 volts on voltimeter at battery ends when reving up

It was REALLY HARD to diagnose since with alternator out of the car every continuity reading was simply perfect... UNTILL thought on spin with the hand and could feel somekind of REALLY SMALL step allmost unnoticeable... tried to find what it was causing and it was that, one ( or two ) of the stator leads making contact with the internal fan blades. It took me one full morning to find out the problem!  bent a little bit more the stator lead, reassemblied and VOILA!!! car on the road again

[b5blue]

HI Neal,

'Thank you' for the info - I'll be sure to make some phone calls and see what I can find out,  . One thing that I did forget to add (not sure if this is relevant or not), but when I put the key in and turn it to the 'on' position (not turning the engine over), the alternator reading goes slightly into the left/negative reading prior to initial start-up.

In the meantime, I was thinking that if I were to start the car to check to see if the voltage regulator got overly warm would anyone feel that it would be best not to actually start the car until I begin to get this squared away?  

Anyhow, I'll keep in touch and thank you again for the helpful guidance,
Aaron
  That is the correct reading, slightly discharge. Find the problem as it could just be a weak charge level or a dead cell in the battery.

[Captain D]

Hello all,

Thank you again B5 and Nacho for the info,  .

That is a good point to keep in mind there Nacho with regards to the stator and rotor - good info that I will certainly keep in mind. To give a little update on the battery so far, I took it to Advance Auto where they did a test and reported that the battery voltage is still really good with no dead battery cells. However, the amp reading should be (if I recall) about the 700 range, yet it was putting out only about 400. As B5 suggested, I opted for the slow overnight charge and I'll pick it up this afternoon.

Over the past few days, the car had come up when chatting w/ local car buddies at work and the jury is still out if it had to to with the 12V Quick Connect piece or not, lol. A few say that the CD player (installed in the glove box so that I can keep my old AM radio stock look in the dash) must have been left 'on' even though the car was technically shut off - yet still drained the battery slowly over time these past few weeks since I've installed the Quick Connect. On the other hand, guys in the other camp said that it wouldn't drain the battery even if the CD player is left on when the car is off - regardless if it is connected to the battery or the alternator .  

With that being said, I'll just leave the Quick Connect off and the CD player disconnected so that I don't run the chance of draining the battery all over again if it was, in the fact, the culprit until I get to the source of the problem. The only other thing that I thought that I would throw out here is that my CB radio is connected to a fuse inside the glove-box. So, even though the CD player is now disconnected, the CB radio still works fine. Just out of curiosity, and since I wish that I knew more about this subject than I actually do, would it be possible that the CB being connected to the fuse directly cause a slow drain from the battery?

Thank you again and I'll keep in touch as things progress,  
Best regards,
Aaron  

[Nacho-RT74]

the battery can be drain no matter where you connect any device, just that conecting to the alt side the ammeter will read that

[Captain D]

HI Nacho,

Thank you for reply and clarification,  .

I installed the battery (minus the 12v Quick Connect + CD player connection wire this time round') and at first start-up, the alternator needle kept jumping to the right whenever I occasionally revved the engine up at idle for at least 10 minutes as if the battery hadn't been recharged. However, after about that time, the ammeter needle seemed to settle all on its own and remained steady at 0 at idle and up to 12+ max when cruising at 50 MPH. I started it up off and on for quick cruises during the remainder of the afternoon and it seemed fine since the battery recharge - only problem was during the cold start when the ammeter jumped to the right at idle for the first ten minutes.

My first thought, since I installed the battery a few days ago, was that something else other than the 12v Quick Connect/CD player was draining it even though I haven't started up the car during those first ten minutes. I'm still going to get everything tested but just wanted to post an update and to see if any of this seems normal just out of curiosity,  .

Thank you again and all the best,
Aaron   

[Nacho-RT74]

on my car with 78 amps alt and full batt just got maybe 20 to 30 seconds get recharged what battery lost on cranking, and thats just a small charge reading which decreases allong the time untill ammeter gets death centered. At least on day cruising, just small flicks when turning lights, or brakes... what inmediatly lifts up the reading as soon regulator senses that to give the alt the order to charge back again.

I can't recall since yeeears ago, when I did the alt upgrade a full right reading on ammeter, not even with batt discharged.

true I have not accesories and just relay upgrades

[Captain D]

Hi Nacho - thanks man! Things have been really busy so I haven't had the chance to get everything tested just yet for anymore updates. The battery is four and a half years old (DieHard) so, I suppose there is the chance that even though I haven't used it a lot since I'm just now finally getting the car on the road, it may not be out of the realm of possibilities that the battery could just be getting old perhaps. But, with no dead battery cells reported with the low amp reading, I'm kind of/hoping that something else was merely draining it slowly these past few weeks (such as the accessory piece).

Thank you again and I'll keep in touch,
Aaron

[b5blue]

Aaron low amp=low volts so 90% chance a new battery (4 years is old for a battery just sitting around.) is the only problem as per that battery low your gauge and Alt. are doing just what they should.