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post #1 of 27 (permalink) Old 08-13-2019, 08:34 AM Thread Starter
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New battery voltage

Just bought and installed an Everstart Maxx H6 battery from Walmart, gave it a charge but this morning it's ready 12.16 volts. Shouldn't a new battery be up around 12.6 or so? I don't see anything that would be draining it. Should I return and replace?
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post #2 of 27 (permalink) Old 08-13-2019, 09:22 AM
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not running that is o.k,should jump up to 13.5 or so running


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post #3 of 27 (permalink) Old 08-13-2019, 09:25 AM Thread Starter
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not running that is o.k,should jump up to 13.5 or so running
Even for a brand new battery? Saw other posts where they say it should read 12.6 or so at rest, 2.1 volts per cell (6 cells)?
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post #4 of 27 (permalink) Old 08-13-2019, 09:38 AM
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Originally Posted by Texdan View Post
Just bought and installed an Everstart Maxx H6 battery from Walmart, gave it a charge but this morning it's ready 12.16 volts. Shouldn't a new battery be up around 12.6 or so? I don't see anything that would be draining it. Should I return and replace?
Sounds a bit low to me, but open-circuit voltage (what you're measuring) doesn't tell you much about the battery's condition. The voltage needs to be tested under load, so at a minimum I'd have the store do a load test and see what happens from there.

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post #5 of 27 (permalink) Old 08-13-2019, 10:33 AM
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Originally Posted by Texdan View Post
Just bought and installed an Everstart Maxx H6 battery from Walmart, gave it a charge but this morning it's ready 12.16 volts. Shouldn't a new battery be up around 12.6 or so? I don't see anything that would be draining it. Should I return and replace?
a new battery that has been charged to full capacity should read 12.6 or 12.66 volts depending on the accuracy of your meter. This does not mean your batteries are bad, just that they are not charged off the shelf which is not abnormal. I would take the truck for a 45 minute drive on the highway, park it for an hour or two, then hop in, dont start it, turn the high beams on, and the blower on high for 30 seconds then check the voltage, if your still not around the 12.4-12.6 range then i would start to worry about the batteries. Note that with the battery isntalled in the truck, you may never see a perfect 12.6. anything over 12.3 - 12.4 is good in my book.


Edit:

To answer the question that is likely to come, the reason you turn the blower and the high beams on for 30 seconds with the truck off is to bleed off any surface charge on the batteries. Its not uncommon after a battery comes off a charge, especially when that charge is from a 200+ amp alternator, for there to be some extra charge in the battery that would read over 13V on a meter, but the battery cant sustain that voltage for more than a few seconds since the chemistry prohibits it, turning the lights and blower on bleed off that extra charge and give you a better reading of what the battery voltage actually looks like. Were you to skip this step after a fresh charge, even a bad battery could read over 13 volts and you may incorrectly assume it is healthy. This step is not required if you are using a true load tester as it will bleed off the extra charge, but if your just using a high resistance meter to test for voltage it does not have sufficient load (almost none in fact) to bleed off the surface charge.
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Last edited by J83; 08-13-2019 at 10:39 AM.
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post #6 of 27 (permalink) Old 08-13-2019, 11:14 AM Thread Starter
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a new battery that has been charged to full capacity should read 12.6 or 12.66 volts depending on the accuracy of your meter. This does not mean your batteries are bad, just that they are not charged off the shelf which is not abnormal. I would take the truck for a 45 minute drive on the highway, park it for an hour or two, then hop in, dont start it, turn the high beams on, and the blower on high for 30 seconds then check the voltage, if your still not around the 12.4-12.6 range then i would start to worry about the batteries. Note that with the battery isntalled in the truck, you may never see a perfect 12.6. anything over 12.3 - 12.4 is good in my book.


Edit:

To answer the question that is likely to come, the reason you turn the blower and the high beams on for 30 seconds with the truck off is to bleed off any surface charge on the batteries. Its not uncommon after a battery comes off a charge, especially when that charge is from a 200+ amp alternator, for there to be some extra charge in the battery that would read over 13V on a meter, but the battery cant sustain that voltage for more than a few seconds since the chemistry prohibits it, turning the lights and blower on bleed off that extra charge and give you a better reading of what the battery voltage actually looks like. Were you to skip this step after a fresh charge, even a bad battery could read over 13 volts and you may incorrectly assume it is healthy. This step is not required if you are using a true load tester as it will bleed off the extra charge, but if your just using a high resistance meter to test for voltage it does not have sufficient load (almost none in fact) to bleed off the surface charge.
Great tips, will give that a shot. Headed to Walmart tomorrow so will have them do a load test too, sure want to make sure my brand new battery mfgd in July is a good one!
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post #7 of 27 (permalink) Old 08-13-2019, 11:44 AM
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Great tips, will give that a shot. Headed to Walmart tomorrow so will have them do a load test too, sure want to make sure my brand new battery mfgd in July is a good one!

Im quite sure the battery is fine, its very rare to get a bad battery off the shelf these days. However its still a good idea to make sure its good before your outside the return period so do the tests and see how it goes. I would bet though that the batteries are totally fine unless there is some other issue with the truck that is so far undocumented.

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post #8 of 27 (permalink) Old 08-14-2019, 12:11 PM
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Did you change just the one?
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post #9 of 27 (permalink) Old 08-14-2019, 12:40 PM
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Did you change just the one?
Thats a good question, i overlooked that possibility, if you only changed the 1, you need to change both at the same time. The older battery will wear down the new battery until they are both blah.
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post #10 of 27 (permalink) Old 08-14-2019, 06:02 PM Thread Starter
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I only have 1 battery. It was totally dead today, tried charging it all day but could only get up to 11 volts. Had to jump the truck with my wife's car, headed to Walmart tomorrow. I don't know of anything that could have drained the battery overnight, no lights or radio left on, what else could drain it?
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