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or a huge pothole, or having the battery clamp pounded on. Exide did some testing back in the early '90s. They tested something like 10,000 failed batteries, and over 9000 of them showed signs of damage to one or both posts, or the connecting strap between the post and the plates, or both.
That's why they even make a tool so you don't need to pound them on. You open them up.
or you take the bolt out, and open them up with a big screwdriver, and put the bolt back in.
I'm just saying that since I personally sold about a thousand batteries in that 4 years, I may have learned a bit about batteries, and their failure modes.
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[quote Racer X]or a huge pothole, or having the battery clamp pounded on. Exide did some testing back in the early '90s. They tested something like 10,000 failed batteries, and over 9000 of them showed signs of damage to one or both posts, or the connecting strap between the post and the plates, or both.
That's why they even make a tool so you don't need to pound them on. You open them up.
or you take the bolt out, and open them up with a big screwdriver, and put the bolt back in.
I'm just saying that since I personally sold about a thousand batteries in that 4 years, I may have learned a bit about batteries, and their failure modes.
I can remember a time when we would jump start a dead car battery remove the cables and the car would run until and if it stalled. There was no auxillary drain for other functions, you could run that old 50 or 60 something until it ran out of gas.
That's how old I am.
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hey, I did that too a few times. great way to fry an alternator, but a car with a generator was OK.
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It was pre alternator days, I said I wuz old.
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[quote Racer X]could go more into it, but the gist is that when the vehicle is already running, the battery pretty much just takes up space, and adds weight.
yeah, right up until you pull the battery cable while the car's running--and the car STOPS. Dead. Right there. All lights, all motor, stopped cold.
The car doesn't keep running without the battery.
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How is any modern car going to run when there's no battery to energize the coils in the alternator?
And I've never had to pound on a battery to install the clamp.
>when the vehicle is already running, the battery pretty much just takes up space
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[quote elmo3][
yeah, right up until you pull the battery cable while the car's running--and the car STOPS. Dead. Right there. All lights, all motor, stopped cold.
The car doesn't keep running without the battery.
Now that's a totally assinine statement to make, mostly because it's blatantly untrue.
It's not even generally true.
A car doesn't 'run'. It rolls.
Engines run. (and not on two legs)
Whether an engine will run depends on the engine's electronic control system(s).
Post-1995, the likelyhood of an engine running depends on whether the alternator will supply power without a load. (numerous damages can occur)
Pre-1995, generally, an engine will run, but again , you risk frying the alternator's regulator (circuit).
*1995, or thereabouts.
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It's a Sears battery. Not sure what the warranty is. I'll be taking it to the nearby Pep Boys to have the battery checked today. If it's the alternator then to we'll be going to our regular mechanic on Sat. His shop is an 30 minute drive away but we' ve been going to him for the past 15 years.
Kap
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elmo3, you obviously have very limited automotive theory background. Numerous alternator designs will operate if disconnected from the battery once the vehicle is running. What usually happens is you send a voltage spike at the moment that the battery cable is pulled, that fries an alternator's diodes. However, this doesn't always happen. I have on numerous ocassions done this with cars equiped with Delco 10 SI and 12 SI series alternators. Blusubaru's link says that it may damage the alternator, but nowhere does it say, for example, that the vehicle will shut off.
As for the voltage spike taking out diodes, in marine applications that use a battery switch, they even make something called a ZAP Stop, which is another diode essentially, that is mounted externally on your alternator. So if someone turns of the battery switch between the engine and tha battery bank, it won't fry the alternator, and the boat stays running.
And as for an alternator actually functioning without a battery to provide power for the field, there are numerous alternators that have a self exciting field. They are also know in the racing community as one wire alternators. You even see race cars with insulated posts on the back. This is for starting jumper cables, as many race cars have no on-board battery. They do have alternators though.
I am ASE certified, and I managed an auto parts store. I have seen and done a few things that you haven't done, and haven't even heard of.
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