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I have hahavebear of a time trying to figure out why my battery voltage won't get past 13V. For reference I have a 440 with electric fans and an electric water pump. Whenever I drive my voltage will be anywhere between 12 and 13 volts with it slowly dipping below when I'm at an idle at a stop light. I ran some tests today and I get
*14/15V at idle coming from the alternator's battery terminal.
*10/11V at both the alt and VR on the green wire connecting the two
*12V on the IGN side of the VR (I have the earlier style VR and points distributor)
*when I was driving, anything I turned on or off (water pump, fans, headlights) would have an effect on my volt meter. i briefly turned everything off while driving and my volt meter shot to a little above 13V and my Ammeter jumped more towards the center (its usually pegged to the charging side when off idle). Does that mean my alternator isn't strong enough? It is a 4 month old remanned Ultima 55 amp squareback alternator. Any help would be appreciated as I am stumped at this point.
Why are you using the double field alternator and grounding one of the field legs?
What's the reason not to use the single wire field alternator?
When I bought the new alternator (before I knew the difference in single and dual field alternators) I just replaced the old one with a matching alt. The old alt was a dual field as well. Once I started reading up on the alternators while having problems not charging in general I found that you could still use this type of alternator by just grounding one of the legs out, or so I read. Hopefully that was correct.
Are you using the old points style regulator or the newer Solid State regulator?
My recommendation would be to use a Powermaster 95 amp alternator along with converting over to the solid state Voltage regulator and add the extra wire for the other field wire. Make sure all the wiring is good or replaced.... "Sounds like you got a voltage drop from a bad wire not carrying the load" Or the Alternator has some weak Diode Rectifier in it.
Also. Make sure the car has all the proper ground wires... Engine to body / Body to chassis / And clean and sand all and all other grounds that you find in the system.
Easy application: 1970 Dodge Challenger 383 CI....
Just my 2 cents..
I just ordered another alternator yesterday actually. It's a proform 110 1 wire. I understand this will now bypass the VR as it has an internal one so some wiring will need to be done but not that big of a deal. Also, comparing a stock crank pulley with the one I have on now, my current pulley is smaller so I'm possibly losing some charging there? I'll test it out once it arrives but only for a minute so I don't fry all the wiring before I replace it with thicker gauge.
https://www.summitracing.com/parts/pro-440-473
That should do the trick... I'm sure the power output wire is large enough... Just need to make sure you have a 12 volt Ignition hot to the field source.
And of course check all the other items mentioned. Are you still running the factory Amp Gauge? If so, Check the wire going through the bulkhead and make sure it is not burnt inside the cannection. May have to pull it apart to really check it good...
Keep us posted... Mopar On... Cheers
So this is where I am stuck now. Got the new alternator in with the battery wire hooked up. It didn't want to crank over till I grounded the other prong to the case. Once started it wasn't charging so I used the green wire to connect the blue IGN wire straight to the battery wire which kept the car running even after turning the key off and disconnecting the battery which I should've know would happen. Still no charging when I did that. Do I have things reversed or am I missing another connection that I forgot?
side note: when It ran it stumbled a lot, wouldn't idle.
Edit:
After doing more testing the idle was just cause it's cold so scratch that. I am getting 16V at the starter relay but battery only at 12.5. I have the battery relocated to the trunk so could it be the length of cable? It's a thicker gauge cable running back there
Going back to your original post. You said you have 14V at the alternator, but only 10-11V at the other end of the wire to the VR. Is that true? If so, you have a poor connection or corroded wire. They can get water up under the insulation that corrodes the wire where you can't even see it. You should never see several volts of drop between the alternator and the regulator.
If I understood your post, you need to replace the wire, not everything else. You have a high impedance connection.
I have the new 110 amp alternator in now and everything seems like it's working. I have noticed an almost chirping like noise coming from it however but it is faint while the car is running. Also, I have developed a misfire at idle but not while at speed. I'm assuming this is fouled plugs and doesn't have anything to do with the alt being replaced but I will know more tomorrow when I pull the plugs to check them.
Should be good to go in that case... All you need is to connect the ignition switched wire and you should be ok..
where exactly will it connect? Right now the only open tab is grounded to the case shown by the line and the battery terminal which is circled is connected to the battery/ammeter wire whichever you wanna call it. If I connect to that terminal won't it be too much volts?
Should be the green pigtail hooks to where you have the red wire grounded....
Maybe I should go look at the instructions for that alternator.... I must be missing something....
I guess I'm going to have to take your word for it.... I have no Idea !!!! I guess if its working? Go with it...
These instuction dont really help anyone out installing on of these.... So I see where you hit a brick wall...
Keep us posted on how everything works out !!! https://www.proformparts.com/images/...structions.pdf
Exactly what I was just about to send, very in-depth😂. As long as the misfire issue isn't electrical related it seems like it's working alright so once I get some new plugs I'll update. Fingers crossed
So good news, I believe everything works great now! Misfire was a spark plug wire that got too close to the header so I trimmed it back to before the melted part and worked perfectly. Now the bad news. I'm not sure if I should just start another thread for this or what but I was pulling back into the parking lot and the starter decided to engage. I stopped right there and turned the key off but it kept turning the engine over until I disconnected the battery. Had to be somewhere else so I threw it in the garage and haven't looked at it yet but not sure where to start. Could the alt have shorted and somehow cause this? It was making a chirp before all of this. I will link a video underneath that you can hear the chirp in if that'd help. Other than that, bad starter relay??
Need to figure out what is squeaking... Water pump, Belt, Idler pulley?
AS for the starter just engaging like that.... I would look at the ignition Switch !!!!
But I do not think that your replacement Alternator had anything to do with the starter issues.... Just a coincidental..
Need to figure out what is squeaking... Water pump, Belt, Idler pulley?
AS for the starter just engaging like that.... I would look at the ignition Switch !!!!
But I do not think that your replacement Alternator had anything to do with the starter issues.... Just a coincidental..
For sure it is the alternator making the chirping noise after testing. I'll try to get to troubleshooting here today or tomorrow. Hopefully it's something simple but I'll start with popping the ignition out.
10-19-2021, 05:49 PM
