electrical short help please!
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From: Spokane WA
electrical short help please!
Got a tech question here.
SO, i would leave the ign off and would find a dead batt when I returned. I followed wires (with a diagram from autozone) and found that the alternator housing has a POSITIVE CHARGE ALWAYS, even with ign turned off. dug a little deeper and found the orange wire on the alternator (which the diagram says goes to the regulator) is the charged wire. SO. Is this wire always supposed to be charged, and the alternator's leaking? or is it NOT supposed to be charged and the regulator's leakin? or, is there another culprit? thanks!
the rig's a 76 f-100
SO, i would leave the ign off and would find a dead batt when I returned. I followed wires (with a diagram from autozone) and found that the alternator housing has a POSITIVE CHARGE ALWAYS, even with ign turned off. dug a little deeper and found the orange wire on the alternator (which the diagram says goes to the regulator) is the charged wire. SO. Is this wire always supposed to be charged, and the alternator's leaking? or is it NOT supposed to be charged and the regulator's leakin? or, is there another culprit? thanks!
the rig's a 76 f-100
Lead Driver
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From: Albuquerque
The positive big wire on the alternator is hot all the time. The case should be ground potential.
Check for things that don't go off like the light in the glove box or a tail light. Could also just be a very weak battery.
Check for things that don't go off like the light in the glove box or a tail light. Could also just be a very weak battery.
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From: west central florida
"the alternator housing has a POSITIVE CHARGE ALWAYS"
[QUOTE=beartracks]The positive big wire on the alternator is hot all the time. The case should be ground potential
so the alternator housing should be 12 volts positive
, which is connected to its brackets, which are connected to the engine, which is connected to the negative side of the battery......that seems odd
[QUOTE=beartracks]The positive big wire on the alternator is hot all the time. The case should be ground potential
so the alternator housing should be 12 volts positive
, which is connected to its brackets, which are connected to the engine, which is connected to the negative side of the battery......that seems odd
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From: Franklin, GA
That wire is hot all the time. The alternator case should NOT ever be hot. Something fried inside the alternator. At a minimum, take the alternator to the parts house and have it tested. And when you replace it, consider replacing the voltage regulator also. I always replace both just as a precaution.
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From: Spokane WA
It's not the big wire that should always be hot. Its a smaller one that goes to the regulator, but i guess that it should also always be hot. I think i'll be able to go get it tested tomarrow. I'll let yall know.
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From: Spokane WA
I exchanged alternators today, and it still does the same exact thing. something that occured to me though was that the alternator is a 74 alternator, and the regulator is of the 76. Maybe they're incompatible?
Here's where i'm at. This is all with the ignition off (and even unplugged right now) :
Chasis has positive charge.
Orange wire running from insulated connection on the alternator to the "F" terminal on the regulator always has power.
Unplug the orange wire at alternator and there's no charge running through chasis or alternator housing.
there's no chance that regulators are interchangable between these years is there? (I noticed the internals look different, but would the 74 regulator solve my problems?)
THANKS
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Here's where i'm at. This is all with the ignition off (and even unplugged right now) :
Chasis has positive charge.
Orange wire running from insulated connection on the alternator to the "F" terminal on the regulator always has power.
Unplug the orange wire at alternator and there's no charge running through chasis or alternator housing.
there's no chance that regulators are interchangable between these years is there? (I noticed the internals look different, but would the 74 regulator solve my problems?)
THANKS
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Try taking the + cable off and putting a test light between the + cable and the + post and see if it lights up. Make sure anything that is hot all the time clock, etc. is disconnected.
Last edited by mark a.; Apr 28, 2005 at 09:38 PM.
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From: Spokane WA
Alright, I got it fixed. The regulator ended up being fried. Thanks for the help guys.
Oh, and the VR in this truck with duraspark is quite different than what was in my other one with points. If you open them up, they're very different setups.
Oh, and the VR in this truck with duraspark is quite different than what was in my other one with points. If you open them up, they're very different setups.
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From: Southwestern Michigan
Originally Posted by 74fordtruck
Oh, and the VR in this truck with duraspark is quite different than what was in my other one with points. If you open them up, they're very different setups.