OK, you guys seem to know it all (that's not intended as a slight)
91 Plymouth Laser (I know, dodge truck NG, but it is a chrysler product, and I do own a dodge truck, and well, you guys know it all). Constant clear liquid around the battery, especially around the top vents, very corrosive. No, the battery does not have a leak Battery was three years old, exchanged with another three year old battery, same thing, clear liquid around battery. Constantly adding water to the battery. Removed regulator from the car, set it up on the test bench, regulator turns on (alternator) at 13.8 volts and turns off (the alternator field winding) at 14.2 volts (at about 70 degrees F). Battery voltage measured at the alternator/regulator, is the same as the voltage measured at the battery. This vehicle uses a separate wire to measure the battery voltage for the regulator, tests OK (same voltage at either end of the wire). With the car running, the measured output voltage of the alternator is 14.2 volts. Manual says voltage should be between 13.9 and 14.9 volts Question is, why am I boiling the batteries. Car runs fine, starts OK, no other problems.
Alright genius, how is that going to make any difference. At best, the voltage between the battery positive and the engine ground will be HIGHER than at both terminals of the battery while the alternator is working. Do you need a lesson on the current path during charging too?
You have to take into account that your problem may be intermittent. Just because the regulator behaves normally while on the bench or while idling in the driveway doesn't mean that it or it's wiring is ok. You will need to keep a voltmeter connected in the car with you for a while to monitor it. If it has a peak hold capability, that would be best but otherwise, you will need to keep it in a place where you can see it without taking you eyes off of the road any more than you would to look at any other gauge. Another thing to think of is that it is not voltage that causes a battery to vent and spit fluid, it is current and high current can flow on both sides such as bad turns in the starter. I would probably look at the sense wire for the regulator and make sure that it is in-tact and has a good solid connection to whatever power source it is tapping from. A bad wire or connection here can cause your problems for sure.
Good point about that intermittent, a bad sense point for example on the regulator, say when it heats up, could definitely cause the overcharge problem. And for the record, I measured the battery voltage at the positive terminal of the battery, and at the regulator plug, with reference to chassis ground, maybe I should have used engine ground, technically they are the same.
The "sense" lead runs through 2 fuses (both good) from the battery.
I'll have to hunt around for a peak hold volt meter Are you suggesting that an over current drawing, starter motor could also cause the battery to spit?
No problem. Another thing that you might want to look at is if something is now constantly drawing current from the battery such as a glove compartment or trunk light that is stuck on and causing the battery to deep cycle. This will also cause excessive current flow in the battery while charging that could cause venting. A bad starter winding could have a similar effect. During your tests, put a current meter between the battery and it's positive connection with everything as you would have it while parked at night and see how much current is being drawn. It should be close to if not zero and if not, you need to find out what is drawing it.
And you wonder whjy people take exception to you...
Really? Unless the battery has a dead cell, voltage across the terminals has every possibility of being higher than battery positive to ground. Typically (remember that lesson you wanted to hand out?) there will be more resistance in a circuit that across the terminals themselves.
Gary is simply trying to establish if that possible resistance is causing the VR to keep charging the battery when it shouldn't.
Maybe you should shut up unless you have something construcive to add.
He's definitely suggesting it, but I think its a real stretch to have that happen. If a starter drew that many amps and still functioned properly, it would lead to the conclusion that the battery was far too small. Of course, you haven't mentioned either the load or the size of the battery, so thats a possibility from where I sit. However, you seem to have a handle on it, so thats a question you should have an easy answer for.
Yawn, not in your case Maxi. We all know that you are just desperate for attention and usually wrong, like now.
LOL, you really don't have a clue. If the alternator is CHARGING or OVERCHARGING, which BTW, is the entire point of this post, the voltage at the battery terminals will NEVER BE HIGHER. Measuring from the battey positive to ground or the negative terminal makes no difference in this case. 14.2V is acceptable from either location.
That is correct but since we are charging, the alternator is the source of the voltage, not the battery and since the alternator grounds thru its case, the output terminals are the alt output connection (+) and the engine block (-), not the battery. BTW, we are concerned about the voltage being applied TO THE BATTERY, not the voltage of the battery itself. Pay attention for a change Maxi.
No he isn't and that makes absolutely no sense at all. If the VR was being fooled into overcharging, the voltage would be much higher than the measured
14.2 at the alternator output which is ALWAYS the same or higher than the voltage at the battery terminals under CHARGE conditions. If the 14.2 was measured at the battery terminals themselves, it is still within accepted voltage range regardless of the possible voltage at the alternator output. BTW, his "piss off" response also proves that he was not trying to do this so you appear to be once again wrong on multiple levels, LOL.
I did have something constructive to say to the OP which is more than I can say about you and as I have said before to you in regard to this last sentence from you, PKB. Now are you going to jump thru some more hoops and falsely accuse me of name calling again, LOL
Sure it makes a difference, in one case there is no resistance possible, in the other you open the possibility to all sorts of resistance. Certainly the voltage you list is acceptable to the system, thats not the issue. The question is whether or not the battery was designed with this in mind (likely it was), whether or not the battery is being accurately monitored by the VR, and whether the battery is big enough to sustain the draw of the starter under normal conditions and the charging of the system under normal conditions. No doubt that the battery voltage "WILL NEVER BE HIGHER" under a charging condition, however, we're still open on the issue of whether or not the VR is seeing the same voltage as what can be found across the terminals.
Terrific, and since the Alternator is putting out specified voltage, it must be grounded just fine.
Ahh yes, pay attention yourself. How does the charging system determine output voltage? Thats right, it monitors battery voltage. So while we are concerned with the voltage being "applied" (charging voltage) we also need to figure out how that voltage was determined. As such, since the VR seems to behave properly on a bench test, we must then look at the switching voltage it sees and determine if that accurately reflects the actual voltage of the battery. (Funny, if you read it, the OP did EXACTLY this test!!) THUS.... Gary asks the question, "Are you measuring battery voltage between the terminals, or from positive to ground?" A perfectly valid question, since we want to know how accurate the info regarding the battery voltage is. It matters not what the output voltage of the alternator is, so long as its in spec, and is switched properly. If the alternator is putting out
14.2v but the VR isn't getting a proper reading of battery voltage and sees it as too low, then we have a great place to find overcharging.
Unless of course, that little "intermittant" word (you do remember bringing it up?) creeps in and blows your whole theory. But lets assume its a constant..... if the VR never sees 14.2, but does see a constant lower voltage, say... 14.0v, it'll keep charging that battery at a rate designed to bring it up just a bit, but never sees it come up.
You can sputter away all you like, the big variables here are the condition of the wiring, how much voltage the VR sees, and how accurate the readings taken have been.
1) Having checked the VR sensing wire, I'd check connections and other details of how it sees battery voltage.
2) I'd also check to be sure battery size is matched to maximum draw, just to cover your theory on too high a draw by the starter.
3) Anything else that was drawing enough current to heat up the battery has to be more than a glove box lamp etc. Generally that size draw will drain the battery long before boiling it.
4) The OP has determined that the VR swiotches properly, but I'd test installed voltage on the VR to see if its performing the same while in the vehicle.
5) Given that battery and charging ALT voltage should be the same, I'd check both the battery (terminal to terminal) and alternator output terminal to CASE, not block etc. If they are th same, and not over spec, I'd look at the VR for problems in switching.
I'm betting this is a deal where something in the wiring is giving a false reading. Which was where Gary was going, and I'll bet you are too.
You took the time to bash Gary prior to just posting what you know. Thats the problem. I've mentioned this before.
BTW, nice job on resisting more posts on that other thread. Got you to shut up nicely, and yes, the reverse psych worked well.
Sure would be nice if you'd just post what you know, and quit being so lame and insulting all the time.
LOL, it is fun to watch you spin. Resistance is not only possible, it is a guarantee unless you have invented the perfect material to make your connections and wires out of. As for the battery being accuratly monitored, LOL. If the voltage is within spec, that is all that matters.
Who cares what the VR sees across the terminals. The only thing that matters is what the voltage actually is. If it is sitting at 14.2, then the VR is function properly, despite your spin.
Never said otherwise. Is this more spin??? If so, then you just spun yourself.
Actually, no it doesn't. It monitors system voltage and could give a rats ass about the battery. Once running, the battery does little more than to act like a giant filter cap to smooth out the mess of crap comming out of the alternator and to serve as a reserve if and when the current requirements exceed the alternators capability at a given time, especially in an older vehicle.
LOL, we need do no such thing, at least not as far as what the OP said he is concerned with. 14.2V is 14.2V regardless of where the measurment is taken, especially with regard to ground.
Hahahahahahahahaha, you really don't have a clue. The voltage is 14.2V BECAUSE the VR set it there.
How does intermittence blow out my theory, oh, that's right, it doesn't.
LOL, you really are kidding, right?!?!? The purpose of the VR is not now nor has it ever been to precisely monitor or control the charging of the battery. Perhaps you should look up the real purpose of the VR before responding. Here is a hint. Although the action of the VR is in its name, perhaps you should look into why it is really needed.
Partially right (sense wire), wrong, and mostly wrong.
With the exception of the VR sensing wire, the rest of what you said means nothing, especially since the VR sensing wire IS how it sees the voltage.
While that is not a bad idea, a bad starter will have the same effect as too small of a battery and even in a defective state, may still have enough umph to start the car.
Once again, you prove your ignorance. It is not the current draw from the battery that boils the fluid or more likely causes venting. It is the significantly increased current draw by the battery itself trying to recharge from a significant discharge state due to that small current draw over a long time that causes venting and venting can cause it to spit fluid, especially if the battery is being jostled while it is venting. This is how a defective starter can also cause venting beyond the short duration of the start.
That is why I suggested he drive with an operational volt meter. Everything is operating normally when the vehicle is sitting still or the voltage would be much higher.
You are daydreaming, talking way over your head, and full of shit. If the voltage is not over spec, then it is what it is and the VR is functioning normally at the time of measurment. There is no rocket science here and we are not talking about percision regulation of voltage or frequency (switching) here. The average voltage is all that matters and if it is in spec, then it is working.
Gary was going nowhere or he would have said so. He got it backwards again like his TC flow and it is as simple as that. As for the wiring giving a false reading, I am not going that way at all since it is complete BS. With the possible exception of an intermittant bad connection to the VR or the alt field winding itself, the wiring has nothing to do with it
He does the same to me as do you and what goes around, comes around. Actually, I questioned his reasoning which is far more than he does with his childish header changes and no text and he could have simply answered my question and proved his reasoning valid but instead just told me to piss off which translates into him being both childish and wrong.
LOL, actually it was your lame attempt at baiting that failed because there simply was nothing else to say there.
LOL, not true. To use the famous Budd line, I am trying to prevent him from giving bad information to and confusing the OP, nothing more. But instead of just bashing him, I asked a question to clarify his response and as usual and much like yourself, he was unable to answer it and not man enough to admit to error or even walk away.
You are right for a change, I did want to and there is simply no reason for me to want to resist but now I am done with this part of the thread so if you want to respond and have the last word, knock yourself out
If I'm correct, I'm obviously not spinning anything. How do you know the voltage is within spec, if you aren't measuring the voltage across the terminals? And if we are both correct that resistance exists in a circuit, how is it possible for your claim to be true, that battery voltage across the terminals will match output voltage, or be the same from positive terminal to ground as it is from terminal to terminal?
Anyone who wants to know if the VR is working properly. Perhaps the OP, in this case.
And you've determined this how? I don't recall any specs being published, let alone a make and model. All we know is that the VR switches on and off at known voltages, and that 14.2 is between those voltages. We don't know what voltages it is supposed to operate between, nor do we know what the system voltage is while its not charging.
But didn't you just say that output voltage and battery voltage are the same? Or are you backing away from that now that you've confirmed my remarks about resistance and properly checking battery voltage?
The OP is concerned with his battery being cooked. Thus we DO need to know how the VR is determining system voltage, and what that system voltage is relative to the battery. Remember, you first claimed that battery voltage and output voltage had to be the same, then you claimed resistance existed in any circuit. So, we're back to my original claim, better check ALL circuits in the charging system and make sure all are intact and functioning properly.
I do have a clue. I'll repeat myself so you can figure it out. Yes, the VR sets the voltage, BUT, how it determines the output of the alternator relies on a circuit that reads system voltage, so..... if that circuit is not functioning properly, and the output exceeds demand, it'll cook the battery. I'm not sure whats so hard for you to grasp here. I've repeatedly said that the VR has to have a good reference voltage, if it does not, it'll call for more output than is needed. It doesn't get any easier than this. Despite the OP having checked the reference voltage circuit, I'd bet something is wrong in that or the VR.
Oh thats right, it means that the VR could jack up the output while no one was looking at it. So we don't know if its a constant 14.2, or just a random reading.
As you previously said, the battery acts as a filter. Thus, if that filter is below its normal level, it will lower system voltage, unless the VR jacks it up. Careful, you are starting to flip flop pretty badly here.
So now it DOES see battery voltage? And I'm sure that you somehow KNOW that this VR is not connected in any way to an ECM? Better check those details......
Right, but will it draw current long enough to boil the battery? Seriously unlikely, unless there are details we weren't given.
Or is it once again you spin? First it was starter draw, now its....
So now, after seeing that the system voltage was sitting at 14.2, you are willing to claim that the battery is drawing down on the system enough to boil the battery, but not enough to lower system voltage? Ok sure.... whatever. Smells of a merrygoround type spin......
Jeez, so I do have a clue, eh?
Oh no, not again, but you just agreed with me, damn, so short lived.....
QUICK!! whats spec for the system??? Ever see it yet? Know what kind of vehicle it is yet?
Is it in spec? Is it ALWAYS in spec? what IS that spec?
I don't recall Gary getting an answer, nor a chance to reply, before you decided you know more than anyone else on the planet.
In a circuit, ya can't get it backwards, one thing affects all others on the circuit. You have to start checking somewhere.
Except your claim that resistance exists and perfect circuits do not. Which will it be?
Oh, you mean the intermittant that I mentioned before, and you claimed had no way of affecting the situation?
More whining. You get it because you give it.
Or bored with your inane bullshit.
YOu just don't get it do you? You claimed in the side bar to this that you were done talking about this sort of thing on this thread, yet here you are. Further, my "lame attempt at baiting" got done exactly what I wanted. You shut the hell up. Finally.
LOL, Please, find one place in this thread or any others where I've insulted you. Or perhaps you are jsu too thin skinned and feel that anything I call you on is an insult? Whatever. I'm sure you'll have an answer.
I'm done here, I explained where I thought the problem is, you flip flopped a bit in trying to prove me wrong, then said exactly what I did using a different method. Then, you did what I figured you would, and tried to argue about your insulting manner, despite claiming you wouldn't continue.
As before, the last word is yours. You cannot resist.
Because the voltage spec is between 13.9 and 14.9 according to the OP and
14.2 is well within that range.
I never said that it was. You really need to stop spinning. I said that the voltage between the terminals cannot be higher than the voltage between the positive terminal and the block because the batteries ground connection is made at the block by one of those wire that has resistance and the voltage he measured was 14.2V, within spec.
If it wasn't working, the voltage would either be battery voltage (no output) OR somewhere above 15 volts (excessive output).
Because an unregulated alternator is capable of putting out MUCH HIGHER voltages.
Because you didn't bother to read it. He posted them.
By not charging, I hope that you mean not running or you really are clueless. He said between 13.9 and 14.9 volts according to the service manual.
Actually, the measured voltage at the batteries terminals is the same as the system voltage, while the actual battery voltage is lower, you do know that, right???? If the system and battery voltage were the same, the battery would never charge. Your comment about properly checking battery voltage is just another example of you not knowing WTF you are talking about.
We need do no such thing. The required voltage needs to be between 13.9 and
14.9 and it was measured to be 14.2, well within spec. If the battery is being cooked at that voltage, the problem lies elsewhere.
You just don't get it. How many circuits do you think exist in the charging system? As for resistance, while it does exsist, it could and many times is so low as to have no measurable effect. If the voltage is within spec, it HAS TO BE functioning properly.
LOL, if the output exceeded the demand for whatever reason, then the voltage would be high, much higher than the 14.2 that he measured. Like I said, you really don't have a clue. You really need to do a little reading and understanding of simple DC circuits.
I have to say Max that you really make me laugh. I really hope that you have a much better understanding of transmissions. If the VR called for more output than is needed, the voltage would rise and rise above the maximum spec as that is the only way the alternator can put out more power than is required. Since the voltage measured is well within the expected range, the VR is working properly at the time of measure.
Yea, it could happen and possibly might. A bad or temperature sensitive connection on the voltage sense wire could cause this very thing and has nothing to do with the 14.2 being a random reading, LOL.
There is no flip flopping except for either your imagination, complete lack of understanding, or a lame attempt at deception. Since the voltage is steady ar 14.2 during his test, I would think that the VR did bump the alt output to bring the system voltage to expected levels. This is the real purpose of the VR, to control the output of the alt to deal with a changing load and output of the alt, not to baby or specifically charge the battery. The battery is just another load that the alt has to deal with. BTW, what exactly are you trying to get at here???
It see's battery voltage until the engine starts, then it sees system voltage as does the battery. Since this is a 91 Laser, I doubt that the ECM has a whole lot to do with it.
No, but it could hammer the battery down far enough that it will require added current to recover and the two combined could cause venting. I didn't say that is the problem, only that it is a possibility.
Now the only one spinning is you. These are just possibilities.
No, smells like stupidity and ignorance on your part. You do remember that thing called a regulator or VR, right? You do know what it actually does, right??? It is the purpose of the VR to detect a heavy current draw from something like a depleted battery (voltage drop) or high beams and boost the output of the alt to compensate for it and to reduce it when the load backs off like when the battery recovers (voltage jump).
No, not really. He did test it in the vehicle but the problem could be intermittent.
No, you just think that I did but I did notice your custome editing by deletion again.
From the initial post:
91 Plymouth Laser - Manual says voltage should be between 13.9 and 14.9 volts With the car running, the measured output voltage of the alternator is 14.2 volts
Perhaps if you actually read the OP's initial post instead of jumoing in blindly and over yuor head to defend you buddy, you would have a little more information to work with, not that it would help you.
Read above and I don't know if it is always in spec. That is why I gave him some suggestions on testing.
I asked him the question and he could have replied to me with a valid answer but chose not to as usual. While I don't know more than anyone on the panet, I know far more about this than the two of you.
He did get it backwards. He thought that the OP was measuring at a point that would have a lower voltage, not the highest like it was.
The resistance is in many cases negligible and in any case, the resistance will lower the voltage, not increase it and it takes a higher voltage to boil a battery.
Sorry Max, I was the one in my first post to the OP that the problem could be intermittent and as stated above, with the exception of the sense and field wiring, no other wiring problem will cause the battery to cook. Care to try again?
That is once again incorrect but why should you break a near perfect record of error.
I would believe that if it wern't for his childish jumps into posts with his lame and unprovoked attempts to insult me.
Actually, here you are. You were the one who brought it up, not me. I said that I was done with the silly side bar, not the main thread where you really don't have a clue as to what you are saying.
More BS. If I responded to it, you would have said that you knew that I couldn't resist and if I don't, you take credit for nothing. The sad thing is that anyone with the I Q greater than a grain of sand knows that lame spin that you try and pull so it really means nothing.
Where did I insult you here? Oh, that's right, I didn't. You could also just post what you know but you rarely if ever do that.
You are done here because even you know how thin and transparrent your spin is getting. That and your false accusations about me flip flopping to distract others and cover your complete lack of understanding in this subject is quite entertaining .Sorry Max, but anyone with an ounce of sense knows that I didn't flip flop just because you said that I did. I had no reason to because quite frankly, you really don't know WTF you are talking about. It is clear that you don't understand the simplicity of an older automotive charging system with your BS about the VR needing to specifically monitor the rate and state of charge of the battery, like in your example of the VR applying 14.2 when the battery needs 14.0 and that cooking the battery, LOL.
As it should be because once again, you don't have a clue.
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