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  #1  
Old 01-30-2010, 01:57 PM
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ricdiculous ricdiculous is offline
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Location: richmond, va
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Alternator charging @ 18 Volts

my alternator is charging my battery at just under 18 Volts. In fact, acid bubbles out of the vents on top of the battery.

after driving a while it seems to level out and go back to a normal charge. (reading 0 on the ammeter).

think it'll blow up the battery?

the battery doesn't get hot, nor do the cables?

I'ma rock it around in the snow here in a bit and see if something heinous happens.

i hope not, don't feel like cleaning up an exploded battery.
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  #2  
Old 01-30-2010, 02:01 PM
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Unless you want to replace your battery, I'd fix the problem.
Overcharging the battery will kill it in a pretty short time frame.
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  #3  
Old 01-30-2010, 02:21 PM
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Tornado230 Tornado230 is offline
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Chrysler mini-vans were notorious for overcharging, resulting in exploding battery.
Fix the problem ASAP.
You will probably find that the battery case is bulged.
Don't stand over it (the battery) while the motor is running.
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  #4  
Old 01-30-2010, 02:23 PM
joe joe is offline
 
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Shut it down. Prolly regulator is kaput.
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  #5  
Old 01-30-2010, 03:25 PM
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yeah, i plan on replacing the battery anyway. is the regulator built in to the alternator on grand wags? it's an 84 by the way. it really only over charges after start up but that's too much in my opinion.

thanks.

Last edited by ricdiculous : 01-30-2010 at 03:35 PM.
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  #6  
Old 01-30-2010, 03:32 PM
joe joe is offline
 
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In 84 it's prolly an internal regulator but not sure.
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  #7  
Old 01-30-2010, 06:29 PM
FSJ Guy FSJ Guy is offline
 
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An 84 should have the internal regulator.

You can get a simple rebuild kit, too, for about $20-$30.

I'd have the alternator checked first. There could be something wrong with your wiring that is causing the alternator to put out too much voltage.
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  #8  
Old 01-30-2010, 10:30 PM
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i think it might be a problem with the wire that's a 15 ohm resistor or whatever the heck it is. i'm going to check that out first. i did see the rebuild kits for 15 bux. i have two extra 94 amp alternators so even a rebuild would cost more than just throwing on one of the others. but if it is that wire throwing on another alt won't fix it.

gonna read the service manual about that wire when i sober up enough.
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  #9  
Old 01-30-2010, 10:36 PM
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Tatsadasayago Tatsadasayago is offline
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A battery that is beginning to short between the plates will cause this as well.

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  #10  
Old 01-31-2010, 10:50 AM
andy d andy d is offline
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dont mess around. If you are fiddling under the hood and a spark touches off the battery , you will get a bath in sulphuric acid. I knew a guy who lost an eye from this.
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  #11  
Old 01-31-2010, 10:55 AM
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could I possibly pick one of those extra alternators off of you?
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  #12  
Old 01-31-2010, 11:06 AM
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gsmikie gsmikie is offline
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just hook a 6 volt battery up to the 12 volt battery =18 volts yea that should do it thast the ticket
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  #13  
Old 01-31-2010, 02:44 PM
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it was a bad alternator.

replaced it, all good.

i have another 94 amp alt i'll sell for 30 bux to whomever was asking about it. pm me and we'll do it up.
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  #14  
Old 02-03-2010, 07:24 AM
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ricdiculous ricdiculous is offline
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so the new alternator did great for about a day and a half, then it started overcharging like crazy too.

turned out i had the field wires reversed.

yeah, i'm a jackass.
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