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what should battery volts be while running

moparjohnny

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my battery shows 12.2 while running,is that the correct voltage?nothing extra on eng just stock. cranks fine. just curious. thanks
 
12.5 resting and 13.8 running
 
12.2 while running means systems is not charging…. what kind of charging system is it mechanical or electronic VR single or dual field alternator ? … You need to do a few test & get out the Mult meter…

Need a fully charge Battery. Check all grounds is a must. And full field the alternator, be careful doing this not to excessed 16 volts at 1500 rpms… If voltage increases Alternator is good, And need to check VR & wiring circuit ..

1969 Chrysler Imperial Charging System Diagnosis Service Guide from the Master Technicians Service Conference Session 256
 
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A fully charged healthy battery, after some settling of normal charging, and a temporarily higher voltage, should stabilize at 12.6 v.
Under charging, with an already charged battery,the voltage should be around 13.8 at any rpm or load, unless the alternator is weak at idle, and that's just something that's been foisted upon us by cheap rewinding nethods.
Your ammeter tells a lot more information, does it go into the charge region when you rev the rpm up some?
Steady 12.2 v will not keep your battery full.
Tell more.
 
A fully charged healthy battery, after some settling of normal charging, and a temporarily higher voltage, should stabilize at 12.6 v.
Under charging, with an already charged battery,the voltage should be around 13.8 at any rpm or load, unless the alternator is weak at idle, and that's just something that's been foisted upon us by cheap rewinding nethods.
Your ammeter tells a lot more information, does it go into the charge region when you rev the rpm up some?
Steady 12.2 v will not keep your battery full.
Tell more.
 
does not go into charge after rev up,this a electronic vr,point distributor,new ballast,new vr.how to check alternator with miltimeter while car is running?
 
does not go into charge after rev up,this a electronic vr,point distributor,new ballast,new vr.how to check alternator with multimeter while car is running?
my alternator only has one attached to field pos,other field pos no wire.been find before now for as charging and ammeter showing proper charge position.
 
Ensure proper grounding at voltage regulator.
At least loosen and retighten bolts on regulator.
If you remove the field with the engine running, you should see an arc as you break the field current.
This would show that the VR is sending current through the field, trying to make output.
If either brush wore out it would not charge at all, so, is there an arc when you connect-disconnect the wire to the field?
 
if you have two tabs, you need two wires.
One from VR positive, and one negative,
which MUST find a good ground.
Did a wire just fall off?
 
if you have two tabs, you need two wires.
One from VR positive, and one negative,
which MUST find a good ground.
Did a wire just fall off?
my harness only had on wire for field.
 
my harness only had on wire for field.
did multimeter test today and before start it shows 12.6 and when i cranked it shows 12.6 never did go up,so its the alternator not charging the battery.
 
I would check all connection at alternator & VR before throwing parts at it….it could be that simple...

What was voltage at alternator positive stud. should be 12volts engine off...
DID you full field the alternator to verify NG alternator… If you have a single field one wire alternator . Remove green wire for alternator. the green wire comes from the Voltage reg… safely ground connection at alternator to ground this will full field…The guide & video give you good pointers...
 
I would check all connection at alternator & VR before throwing parts at it….it could be that simple...

What was voltage at alternator positive stud. should be 12volts engine off...
DID you full field the alternator to verify NG alternator… If you have a single field one wire alternator . Remove green wire for alternator. the green wire comes from the Voltage reg… safely ground connection at alternator to ground this will full field…The guide & video give you good pointers...
thanks pop,i went back to check and i did leave a wire loose from the voltage regulator,plug it up and ammeter is setting where it should be. thanks
 
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