Alternator, battery readings
#1
Alternator, battery readings
Do these numbers seem ok? I took them with two different meters, a fluke and a Milwaukee. The Milwaukee had higher readings.
battery with ignition off 12 and 12.73
running at battery 13 and 13.96?
I read somewhere under 14 with it running is no good? Replace the alternator?
battery with ignition off 12 and 12.73
running at battery 13 and 13.96?
I read somewhere under 14 with it running is no good? Replace the alternator?
#2
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Car: '89 Firebird
Engine: 7.0L
Transmission: T56
Re: Alternator, battery readings
Put down the tools and step away from the car!
Alternator is definitely working. So I'm guessing the difference between the first set of readings and the second set of readings is you let the car run for a while and charge the battery?
Alternator is definitely working. So I'm guessing the difference between the first set of readings and the second set of readings is you let the car run for a while and charge the battery?
Last edited by QwkTrip; 12-16-2018 at 01:15 PM.
#3
Re: Alternator, battery readings
Battery is charged. The first reading was done with a fluke meter. The second was done with a Milwaukee meter. The first set of numbers were with the car off and checking the battery. The second group was with the car running, 13 for the fluke meter and 13.9 for the Milwaukee meter.
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Re: Alternator, battery readings
What are you complaining about then? Why you so eager to replace an alternator?
Come on don't make me fish or I'm going to go away and you can do this yourself.
Come on don't make me fish or I'm going to go away and you can do this yourself.
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Re: Alternator, battery readings
Dumbass
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Re: Alternator, battery readings
See, you communicated pretty clearly there. Now do the same when it matters.
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Re: Alternator, battery readings
Sorry, if I had known you were 16 then I wouldn't have called you a dumbass. At that age it's just still part of your nature and you can't help it.
Joking aside, All your voltage readings could be legit depending where the voltage was measured, condition of battery, position of the key switch, and if any electrical devices are wired around the key switch (directly to battery). Right now you might have a battery about to fail, or an electrical drain on the battery with key off, or nothing wrong at all, or..... ???
A battery with 12V "open circuit voltage" is a battery deader than a door nail. But not sure where you made measurements and whether there was a current draw on the battery. After a battery is charged it will carry a residual surface charge for a while so that could be why you got 12.7V. But again, not sure what you actually measured. You say the battery is charged but just because it takes a charge doesn't mean it is healthy -- unless you know you had just installed a new battery. But again, we don't know. 13V and 13.7 is alternator working in both cases. But it is suspicious that the voltage climbed so fast to 13.7V unless the battery has really small capacity and is about to die.
So many questions.... so many possibilities.... with no way to narrow the options unless you start sharing more of what you know. You said you have some electrical problems. Describe that too and it might reveal something.
Joking aside, All your voltage readings could be legit depending where the voltage was measured, condition of battery, position of the key switch, and if any electrical devices are wired around the key switch (directly to battery). Right now you might have a battery about to fail, or an electrical drain on the battery with key off, or nothing wrong at all, or..... ???
A battery with 12V "open circuit voltage" is a battery deader than a door nail. But not sure where you made measurements and whether there was a current draw on the battery. After a battery is charged it will carry a residual surface charge for a while so that could be why you got 12.7V. But again, not sure what you actually measured. You say the battery is charged but just because it takes a charge doesn't mean it is healthy -- unless you know you had just installed a new battery. But again, we don't know. 13V and 13.7 is alternator working in both cases. But it is suspicious that the voltage climbed so fast to 13.7V unless the battery has really small capacity and is about to die.
So many questions.... so many possibilities.... with no way to narrow the options unless you start sharing more of what you know. You said you have some electrical problems. Describe that too and it might reveal something.
Last edited by QwkTrip; 12-16-2018 at 06:05 PM.
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