Did you try buying one of those battery testing units at auto parts store or checking the level and adding some distilled water?
Dealers are always looking at ways to *bill* you for something or the other.
2004 4Runner still on OEM Panasonic battery
- Thread starter Jed
- Start date
Did you try buying one of those battery testing units at auto parts store or checking the level and adding some distilled water?
Dealers are always looking at ways to *bill* you for something or the other.
Both of you are right actually;
DoCMT is correct your alternator normally provides all the required power to operate the vehicle AFTER it has been started. The battery is mainly for starting the vehicle as this will draw the most amperage out of any operation of the vehicle. BUT, the second thing an alternator does is recharge the battery's lost charge when the vehicle is cranked over.
The key idea there is that an Alternator and the Regular Auto Battery are not designed to Deep Cycle...
Deep Cycling is drawing a battery to a low charge level, (in the case of automotive batteries is it is below 9.5volts it is often considered a "dead battery") and the charging it back to a full charge status repeatedly.As a rough rule of thumb it takes roughly an hour worth of driving to recharge the battery the amount you drained from cranking it over. Now imagine your alternator trying to keep your car running AND recharging a dead battery, it literally burns itself out. The alternator is not designed to hand that much of a load, its meant for essentially operating the vehicle and topping its battery off not recharging it from zero.
DCDude is also right, pretty much any dead/weak battery will not usually start a car, though that is why people get jump starts.
Sorry if its written rather jittery like, trying to keep it concise without going into how the battery operates as well as the charging and starting systems in too much depth. (Though I guess if you'd like I could knock it out if people really want to know? :shrug
Actually, I made the point highlighted above.
So I’m trying to find out how to read the date codes on the Panasonic battery in my sons 97 4runner we bought used and I run across this forum. If I understand it right, you cannot get Panasonic batteries here in the States. If that’s true, then this battery is 14 years old? No way or is there? Maybe I should contact the Smithsonian Institute.
Silly statement. Depends upon many different factors. I had a battery that wouldn't hold and charge and it would start my vehicle for at least 3 days before it would no longer have enough amperage to crank the engine.
Besides, I wasn't talking about "starting" the vehicle. I was talking about running the vehicle on a weak battery that won't hold a charge. You could always jump start the vehicle and run it on the bad battery. Do that for a while and see how long your alternator lasts. If you somehow believe that a bad battery doesn't cause your alternator to work excessively, there's really nothing else to say here. I suggest you read up on the subject, especially considering your screen name.
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Talk about heading down a path of diminishing returns.
If you have a weak battery that needs to be jumped, then you're begging for pain if you don't replace it...whether it affects the alternator or not.
:banana:
The fact remains: A bad battery will overwork the alternator. In time, it will kill the alternator.
The fact is that it's a moot attempt to make a point because one should be changing the battery as soon one realizes that the battery has issues when leaving lights on is not the culprit.
Anyone willing to to continue using a battery that needs jumping after "3 days" is begging for pain whether it results in a bad alternator or not.
Wow, talk about back-pedaling. LOL
I give you a factual situation to illustrate (and prove) my point and all you can come back with is that it's a moot point because anyone in that situation would be asking for trouble? Sorry, but that's weaksauce to the tenth degree.
Facts are facts and what I said is a fact. Next time you want to debate, bring some facts to the table.
You really didn't prove anything, and the point you tried to prove was actually a ridiculous scenario to begin with.
Alternators run non stop when the engine is running, so a bad battery has little to no impact on an alternator.
The scenario was only mentioned to illustrate the point I made earlier in the thread. It's kinda funny that you can't wrap your head around that. In reality, plenty of people will recharge their dead battery and not chage it unless it dies again. So to say it is a ridiculous scenarios is just...well...ridiculous of you.
And yes alterators run non-stop when the engine is running. No kidding there, genius. But a bad battery does have an impact on the alternator. Did you know that the higher the load on the alternator, the more HP it consumes from the engine? Thats right, Sparky.....a hard-working alternator is more difficult to spin than one that's not forced to provide a lot of current to the electrical system. There's another fact that you couldn't have possibly known, based upon the last sentence in your quote above.
Now put it all together and tell me again how a bad battery has "little to no impact" on an alternator. Better yet, go read up on the subject and come back when you're more educated on how 12V electrical systems work.
You're probably the only person on this forum who may continue to jump start their battery despite it giving you every indication that it's on its last leg.
An alternator is working no harder with a bad battery compared to a good battery. The only issue is whether the engine is running just long enough to give the battery enough juice so that it can start the car next time.
If you're sitting in your car for no reason but to wait until your little 12V battery is charged just enough to start the next time, then you need to either a) get a life, or b) borrow some money from mom to get a new battery.
Anything beyond that is what you imagine when you're asleep at night under the covers.
I never said I did that. What I said was that I had a battery that wouldn't start my car. I recharged it and it was fine for three days before it died again. So I replaced it with a new battery. Sorry, but plenty of people would do the same exact thing. And actually, if you read my other posts, you'll see that I replaced the Panasonic battery in my 4Runner just because it was seven years old, even though it showed no signs of dying. So save your sarcasm for someone who cares.
Wrong. Alternators worker harder as load increases. And as an alternator works harder, it saps more power from the engine because it becomes more difficult to turn the alternator pulley. So if the alternator is supplying the car's electrical needs AND continually trying to recharge a bad battery, it is in fact working harder. That's not even a debatable fact, but I'm not surprised that you'd say something so foolish.
You really need to educate yourself before you continue posting. Or I guess you can just keep acting like you know something instead. Either way, you're coming across as ignorant.
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You may or may not have noticed, but that alternator is running non stop whether the battery requires recharge or not. There is no extra load on the engine to recharge the battery whether the battery is drained or fully charged. There is no battery monitoring unit in the car that makes the engine work harder to charge a "weakened" battery....except in your Bizarro world.
Eastcoastrunner
New member
take it to PM's lol
Umm...yes, there is extra load on the engine. I'll say it one more time in the hope that it sinks in for you: The more amperage (load) demanded from the alternator, the more physical resistance (turning the pulley) the alternator is putting on the engine. In other words, as the electrical system draws higher amperage, the more HP required to turn the alternator pulley. This is pretty basic stuff and something that you should understand if you're going to discuss this intelligently.
Read this:
How Everything Works - Question 1224 - Printer Friendly
It applies to alternators as well as generators.
How Everything Works - Question 1224 - Printer Friendly
It applies to alternators as well as generators.
Nah...you're full of it.
The Thomas J
New member
2005 v8 with an OEM still going strong.
