Optima Battery Failure Characteristics, Engine Turns over slower and slower |
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Optima Battery Failure Characteristics, Engine Turns over slower and slower |
Spoke |
Jan 21 2008, 11:01 AM
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#1
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Jerry Group: Members Posts: 6,994 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None |
I have a red top Optima battery in my 74 and over the last few months, the engine has been turning over slower and slower. What are the characteristics of the Optima when it is going bad?
Lead acid batteries usually just dump and won't start the car. I haven't checked the voltage at rest or while the engine is running to see if it's the battery or my charging system. I guess that will be tonight's activity. Can I use an external charger to try to put a full charge on the battery? Thanks, Spoke |
Spoke |
Jan 22 2008, 11:42 PM
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#2
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Jerry Group: Members Posts: 6,994 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None |
I measured the resting battery voltage to be 12.28V (no load). My charger puts out about 15-16V while dumping in about 2 amps. After about 1/2 hour of charging, the battery voltage with parking lights on was 12.48V.
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banger |
Jan 23 2008, 01:28 AM
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#3
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Member Group: Members Posts: 354 Joined: 12-November 06 From: Santa Clarita Member No.: 7,205 Region Association: Southern California |
With a resting voltage of 12.28v, this indicates roughly that the battery is around 50% charged. It should read at least 12.65v to be fully charged. You may want to get a good charger and see if you can charge it up full. Expect to pay $80-100 for a good computerized charger. Most cheap chargers are "dumb" chargers, and wont charge the battery properly. A good computerized charger will use a 3 step process to get the battery to full charge. Also to fully charge a battery int he car, you must deliver at least 13.8 volts from the alternator. You will need around 14.4v to properly "top off" a battery for maximum capacity. If you dont top off a battery regularly, then it will eventually build up sulfate, and will fail.
I measured the resting battery voltage to be 12.28V (no load). My charger puts out about 15-16V while dumping in about 2 amps. After about 1/2 hour of charging, the battery voltage with parking lights on was 12.48V. |
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