Electrical Help Please

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SleeperDart505 said:
OK so you're saying that the alternator and voltage regulator should both be good? And am I to infer since you didn't mention the battery that you think it is the issue?
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I don't know which starter is on the engine. Looking at an FSM, older Chrysler starter will draw around 180 amps from a higher compression v-8.
The new Denso starters many use may draw less.
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My point here is that you can use your starter as test load like I suggested earlier. Start with a fully charged battery and the votlage it drops to during the start will give you a ballpark idea of its internal condition.
 
I also think it will be really helpful to figure out the battery and new circuits have been connected into the original system.

All I have to go from is the photos posted.
It looks like power for the fans comes from a connection by the firewall or inside or ?
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It looks like there may be three wires on the relay stud?
Guessing
One heavy ga from the battery
Second heavy gage either to the starter (which could be a problem) or to feed relays or an auxilery fusebox or such.
Third may be the original connection to the main junction via the ammeter.
 
Alternator looks like a "revised squareback". As long as it has a matching regulator - and it looks like it may, that is probably about as good as it gets without switching to a much newer design. Whether, at slow idle, it can recharge the battery at the same time as running the fans - that i don't know. For that you will need a real test.

It is possible that the alternator would still work, but more weakly, with one leg of the field out of commission. So far nothing posted makes me think thats the situation. it seems to have no trouble producing power after start up. I'm assuming that was at slow idle.

What's a real alternator test look like?
It shows maximum current the alternator can produce stepping up from the slowest rpm until it maxes out.
Or if you have the factory specs for that alternator (I don't) test for maximum current output at the spoecified test rpm (usually 1250 rpm).

Here's a test sheet that came with a revised squareback (Lester number 7509)
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and here's one Dana posted for a regular square back (although lester 7007 can be a roundback so not sure if the two got mixed up in testing)
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The main point here is the alternator's capacity to create power increases from nothing at its turn on rpm.
Knowing the alternator rpm (pulley ratio) one can compare the output an alternator is capable of to the maximum loads expected while idling.
If it can't , and you want to stick with the electric fans, then a Denso is probably the way to go.
Butthat's skipping way ahead. We don't know that's why the battery is loosing charge.
Solve that first.

Longer discussion here about graphs
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Reading Alternator Output graph

I received this testing report with an aftermarket alternator I purchased for a project. Just want to make sure i'm reading it right and figured someone on here would probably know. The graph shows the Amp output vs RPM, this is the rpm of the alternator not the engine correct? Since the graph...
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Thanks everyone for all the comments and suggestions. I'm pretty good with everything but electrical issues. With them I am a lost ball in high weeds. :BangHead:

Since I could not get a definite answer out of anyone and neither of my local parts stores could produce a reliable test, I have just decided to buy new parts. I think this will solve the problem and give me piece of mind when I drive the car. I'm tired of the battery going dead and leaving me stranded.

Just for the curious........, I found a company here in the USA that is building the square back alternators BRAND NEW. Not rebuilt or remanufactured. After talking to both Managers of the local auto parts stores and hearing the horror stories about all the JUNK they get from the rebuilders and remanufacturers in Mexico and South Korea, and Vietnam, I didn't want one of them. They both said the failure rate was pretty high and sometimes were bad right out of the box. I got the brand new one for $170. The quality from a company from the USA should give me much better chances of getting a good one.

For the battery I bought a 24F Die Hard Platinum AGM battery. I hear the AGM gel filled batteries are less effected by vibration so it will last longer since I plan to drag race some. It has 710 cranking amps and 885 cold cranking amps. It also has 120 minutes reserve capacity. The long reserve capacity should help me with those electric cooling fans on my car since the engine stays pretty cool and the electric fans don't really run all that long.

I'm really hoping that this puts an end to me getting stranded everywhere I go. I'd like to drive the car without worrying about it. If this doesn't fix my issue I'll be back asking for additional ideas. Should I go ahead and buy a voltage regulator now? I seem to have bought everything else!:rofl:

Thanks again for the help!
 
I have always thought it was a good idea to replace the regulator with a new alternator. Probably no real science there, just a personal preference.
 
Neighbor's camaro had a bad VR that drained the battery overnight. We watched my voltmeter while unplugging fuses and nothing...

Until we unplugged the VR. That was it, replaced and drain was gone.

I read somewhere(sorry no citation) that jumping a battery with a solid state VR can cook it. No idea about the validity of that claim though
 
My wife's BMW battery would die once a month. I trickle charged overnight 2 amps. Brought to AutoZone for a test. They said it was fine. Car was charging fine. This went on for a year. I finally broke down and bought a Battery. Never had an issue since. My opinion was a bad cell or low cell (sealed battery). Good luck and keep us posted.
 
Kendog 170 said:
My wife's BMW battery would die once a month. I trickle charged overnight 2 amps. Brought to AutoZone for a test. They said it was fine. Car was charging fine. This went on for a year. I finally broke down and bought a Battery. Never had an issue since. My opinion was a bad cell or low cell (sealed battery). Good luck and keep us posted.
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I had a Taurus that the gauges would go crazy on sometimes, mostly when I started the car. They would flop all over until I turned car off and restarted it. Looked at online posts, lot of people had this trouble and some spent thousands trying to fix it. One guy suggested buying a new battery. I did that (even though the car always started great), and it never happened again. Weird things can happen with batteries sometimes.
 
Kendog 170 said:
My wife's BMW battery would die once a month. I trickle charged overnight 2 amps. Brought to AutoZone for a test. They said it was fine. Car was charging fine. This went on for a year. I finally broke down and bought a Battery. Never had an issue since. My opinion was a bad cell or low cell (sealed battery). Good luck and keep us posted.
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That's kinda what's going on here. I keep it on a trickle charger yet when I'm out driving the car, after several stops the battery gets weak enough that it won't start the car. It's maddening.
 
Justn my $.02 but now its $.05 ajusted for inflation... :poke:

1. Check the date code on teh battery it will be a colored dot sticker with something like K-8 (2018)
in this example the battery is 6 years old may want to get a new one most batteries are 60 month and my personal rule is 5 years .

2. You stated high comporession what is the cca 1000 volts? I like 1000 cca for high comp applications.

3. Check for parisitic draw killing the battery. turn car off take key out of ignition hook an ammeter up after you disconnect the battery negative, hook probes or test light between cable and neg terminal,
check amps OR use a test light a nice bright light mens something is drawing off the battery when the key is off..50-80 miliamps on new cars is normal for all the modules aND LESS THAN 50 MILLIAMPS IS NORMAL ON OLD CARS FOR PARISITIC DRAW. Caps lock not yelling. Trunk and glovebox lamps used to stay on they were the culprit usually but in a race car who knows what it could be...

4. If you can get it where it cranks do a load test hook up a volt meter while someone starts the car see if the volts drop to less than 9.6 cranking if it drops to less than 9.6 battery fails load test.

5. is the starter getting cooked by header heat...? if so the car should start after sitting a while...

and not necessarily in that order...good luck :thumbsup:
 
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