| Author |
Message |
Doyle Gaither (Texasborderdude)
Registered Member
Username: Texasborderdude
Post Number: 102
Registered: 3-2007
Posted From: 75.202.242.24
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, November 26, 2007 - 12:17 pm: | |
I just replaced 8-6volt Interstate batteries. My digital volt meter reads 12.85+/- at full charge, butt the hydrometer (new) registers only 1/2 charge or so. (1.25 specific gravity if I remember correctly.) I'm not getting the numbers of hours I'm expecting on a the "fully charged" new batteries... but don't have a real benchmark yet. Shouldn't the hydrometer be the most accurate measure of charge (By the way my 8d's for the engine batts register full charge according to the same hydrometer) Wouldn't this need be checked out my Interstate?
dg |
Jack Conrad (Jackconrad)
Registered Member
Username: Jackconrad
Post Number: 676
Registered: 12-2000
Posted From: 76.3.169.171
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, November 26, 2007 - 12:31 pm: | |
I just ran into the same problem on my son's car. Engine would not crank. Digital volt meter showed 12.6 (until starter was engergized, then dropped to 9.2) Hydrometer showed all cells in "Fair" condition. Battery was charged and re-tested, same results. New battery and problem solved. Don't know why i got the readings I did. Jack |
niles steckbauer (Niles500)
Registered Member
Username: Niles500
Post Number: 806
Registered: 11-2004
Posted From: 71.43.39.156
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, November 26, 2007 - 12:38 pm: | |
Doyle - just tried to call you - it sounds like you need them load tested - did interstate install them ? |
joe padberg (Joemc7ab)
Registered Member
Username: Joemc7ab
Post Number: 171
Registered: 6-2004
Posted From: 66.38.159.33
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, November 26, 2007 - 12:43 pm: | |
Doyle
According to Trojan battery literature: 1.25 specific gravity is about 85%state of charge. Fullstate of charge should show an open circuit voltage of 12.73 volts and S.G. of 1.277 corrected to 80* F.
Joe. |
Gus Causbie (Gusc)
Registered Member
Username: Gusc
Post Number: 548
Registered: 11-2005
Posted From: 63.97.117.17
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, November 26, 2007 - 10:51 pm: | |
As you have discovered, a voltmeter is almost worthless for testing batteries. A battery will still show 12 v when almost dead.
Load testing is the most accurate. Specific gravity should just about as good but it isn't always, have no idea why not.
You can get a decent load tester for $20 at HF.
I use both when in doubt.
(Message edited by gusc on November 26, 2007) |