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RIP (12/27/60-7/18/15)
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767 Posts
Discussion Starter #1
Howdy all,
I ran my Goat for about 20 minutes. :)
Mwaaaaaaaaaaa............ as it was cooling down.............
I put a voltmeter on the battery.motor off I read 12.7VDC
running I got 12.5 and it slowely rose from there to like over 12.8VDC.
just for s&g's I revved up the motor pretty high and the meter shot up to 15 something VDC.
I have the old external v. regulator.
Is this normal? thanks as always
Tk
:party:
 

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15v is a bit high...motor running 13.2 is optimal....could be the regulator is a little off or the alternator is tired. E
:agree One of the reasons "the industry" converted from generators to alternators was that the latter works better at low rpm. Sounds to me like you could have a little of both --- an alternator that's getting tired and a voltage regulator that's sluggish to react. I notice on my 69 the GEN light will flicker when the motor's cold and in serious 'rumpity rump' mode. Once it warms up and idles around 1000 rpm, it's fine. Right now it has the same alternator that it last ran --- 25 years ago ---. I had it checked at AZ before I put it on and it tested good, but still....

Bear
 

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15v is high, but it's charging, so that's good.
If it runs high all the time then it will boil the water out of your battery, if it puts out less volts as the battery increases, then it's OK. I'd leave it alone and see if it acts up. I like to put the one wire self exciting alternators on mine and ditching the entire external regulator and other two wires for internal regulated, but that's just me, less wiring is better. If you want stock, it's fine. Get a new voltage regulator and try that if you think it's a problem.
 

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RIP (12/27/60-7/18/15)
Joined
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767 Posts
Discussion Starter #6
If I switch to an alt with an internal regulator, what wiring changes need I make?
thanks as always
 
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