Battery/alternator question
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Joined: Dec 2001
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From: Lincoln USA
Battery/alternator question
My '68 F-100 was purchased in Feb. 01. One of the first things I did was replace the batery with a new one. My voltmeter gave a reading of 12.5V at idle, 12.75V at 1200RPM. I drove the truck daily for about a year, then got a 91 Taurus as a daily driver, using the pickup for "truck" things. It sat for a month unused. Then last week I went to start it to move it out of the driveway as the Taurus was going to be parked for a while waiting for a new tranny. It wouldn't start. Put the voltmeter on it: 0.0V! Jumped it with the wifes car, let it idle for an hour. Still got a reading of 12.5 at idle. Went to start it today. Nothing. 0.0V! Put the battery from the Taurus in it. Guess what? 14.3V at idle, 14.9 at 1200 RPM!!
My question is: Is it possible for a battery to have an 'internal short' that would keep it from charging properly and cause it to self dicharge?
It seems to me that I should have been getting 14V+ readings from either battery.
Pardon me if this question seem stupid but I'm an electrical idiot. And I don't want to be stranded with a dead battery.
Thanks in advance, all!
My question is: Is it possible for a battery to have an 'internal short' that would keep it from charging properly and cause it to self dicharge?
It seems to me that I should have been getting 14V+ readings from either battery.
Pardon me if this question seem stupid but I'm an electrical idiot. And I don't want to be stranded with a dead battery.
Thanks in advance, all!
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Joined: Jan 2008
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Battery/alternator question
I've seen them NEW off the shelf with Internal shorting.
They should always be testing when buying one.
If the salesman complains Why test it,because "It is new"
Reply with: "I'm from Missouri, Show Me!"
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They should always be testing when buying one.
If the salesman complains Why test it,because "It is new"
Reply with: "I'm from Missouri, Show Me!"
[font color=red]Dennis
FTE Assistant Administrator
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Post Fiend
Joined: Apr 2002
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From: Central Kali
Battery/alternator question
This is a strange one. 
I don't see how the old battery could keep going that long with voltage that low. I would replace it and keep a close eye on the voltmeter. Turn on the lights and other loads and see if stays around 14v at a fast idle.
I don't see how the old battery could keep going that long with voltage that low. I would replace it and keep a close eye on the voltmeter. Turn on the lights and other loads and see if stays around 14v at a fast idle.
Senior User
Joined: Jul 2002
Posts: 234
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From: Jacksonville, FL
Battery/alternator question
If a battery is dropped on a hard surface, the lead plates inside are almost certain to break up even though the plastic housing may not. I've seen them dropped off a pallet at the parts store, not checked and just put on the shelf! A check you can perform on your truck, with everything off, set your voltmeter to DC amps, place a probe end on the battery + terminal with the cable disconnected. place your other probe end to the cable and any amp draw will show up on the meter.
A very slight reading could be due to accessories such as a stereo w/ a preset memory...etc. anything over 0.5 could very well run a battery down. sounds like you fixed it already though.
A very slight reading could be due to accessories such as a stereo w/ a preset memory...etc. anything over 0.5 could very well run a battery down. sounds like you fixed it already though.
New User
Joined: Jan 2008
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Battery/alternator question
For automotive batteries to last as long as possible you must
Use it > Charge it > Use it > Charge it >etc
Without being used in this manner and just left sitting they will
Sulfate(sp)and go bad.
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Use it > Charge it > Use it > Charge it >etc
Without being used in this manner and just left sitting they will
Sulfate(sp)and go bad.
[font color=red]Dennis
FTE Assistant Administrator
[/font]
[link:www.ford-trucks.com/guidelines.html|Club FTE]
[link: motorhaven.autoanything.com|How YOU Can Support This Site]
http://www.clubfte.com/users/mil1ion/canada_flag_animated.gif
[link:www.clubfte.com/users/mil1ion/Mil1ion.html|My Website,"North Of The 49th"]
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