Battery issues

FuryDan66

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So about a month ago my battery (new) just up and died on me. Now I'm sure there's probably a short somewhere but I disconnect the battery each time she sits and come out to find it dead again. What could eat away at my battery life? Could it be a bad alternator while I'm driving that's draining it or possibly just a bad battery ?
Dan
 
If you are disconnecting the battery and it doesn't hold a charge, it's a bad battery.

Probably a shorted cell...
 
That's what I was thinking. Well they replaced it so I'm hoping that's it lol.
Thanks,
Dan
 
If they replaced it then they tested it so it must have been bad. No place around me would exchange a battery unless they knew it was bad.

I leave my 66 300 battery hooked up all winter. It might go 2 to 3 months before I start it. 5+ year old battery still no issues with the battery discharging.
 
i always buy batteries from my local battery guy. not a big box store. pay the extra coin get a good one and you support the local guy.
 
So on the instrument panel while drive it will read charged while driving. I had the battery up there about a month ago and spent 3 hours waiting for it to charge. Once it did they told me it was fine. Now I've driven it a handful of times up till today and each time I always just unplug the battery bc I never know how long before the next drive.
 
This is the battery paid a pretty penny. Not sure who the local battery guy would be to be honest.

1527614567946856702254.jpg
 
Thanks FuryDan66. That gauge looks right in the middle (to me anyway), not working. Sometimes I've had issues with my 50 year old wiring harness and the battery was not charging. I could tool around town ok for a while, but as the new battery wore down,.... I had a similar crisis.
I then dropped a voltmeter across the battery and low and behold it was not charging. This is where I am coming from. If you measure the voltage you will know for sure, and having a voltmeter around is always a good thing to have in your (literal) tool box.

I'm sure you may know this, but here is what you do, just in case.
Set the meter to DC volts, with the car off and press one lead down on the positive side the other on the other side.
The voltage will be about 12V. Start the car and measure it again. It needs to go up. 13V, 13.5V or there abouts, is perfect.
If it doesn't go up, stays the same or less, something is wrong and it isn't your battery.

On the other hand, perhaps you just had a crappy battery, or sometimes a dead dead dead battery will wind up being unchargable and NFG.
But if you disconnected it after every use, it isn't going to drain through a short circuit/load in the car, since it is open-circuited.
If you re-attach the battery cable to the terminal and see small sparking going on, then you have a short somewhere in the car. Pull one fuse at a time until it no longer sparks to isolate the fault.

Alternator - Sometimes an alternator that is on its way out, will be intermittently bad. These can be hard to catch. If you see smoke pour out of your hood near the battery, it could be one of those flaky moments, where the internal regulator is being bad, overcharges the battery and boiling steam comes off, or the battery explodes. Most of the time though you will catch this happening.

Sorry for droning on, hope some of this helps.
 
Man thanks a lot, I would rather had too much info then not enough. I'll try this later on today or this weekend and report back;).
Dan
 
Although many good points have been listed, a couple of things to look for also. See if your glove box light, trunk light, or cigar lighter are on. If any of the three stay on, it will drain the battery. Also do you have a factory radio? If you have an aftermarket one, the internal clock can do it also.
 
Factory radio that's in it now, I'll check later to see if anything is staying hot while it's off ;)
 
So with the car off it went up to 12.6 and with the car running it dropped down to 12.48. Would this explain why my headlights are so dim also?
 
So with the car off it went up to 12.6 and with the car running it dropped down to 12.48. Would this explain why my headlights are so dim also?

System is not charging. There is a problem somewhere in the charge circuit, ie, alternator, regulator, or wiring harness.

Yes, also explains dim lights.
 
Agreed something wrong in the charging should be upper 13 amps at least when running. If you want to rule out the alternator, take it off and have it checked. Mine last summer was my voltage regulator. Buy the solid state one if only 10-15 dollars more if it is not the alternator.
 
I did just change out the voltage regulator about 5 months ago. I will say this alternator looks pretty old lol
 
If the alternator is charging it should be magnetic at the rear bearing cover. While the car is running, carefully hold a screw driver to the centre of the alternator at the back - it should have a mild magnetic attraction if It's charging.
 
Simple alternator test is this...

Disconnect the field wire at the alternator. Use a jumper wire to connect the alternator field connection to the alternator output. Connect a voltmeter to the battery. Turn on the headlights (high beam) and start the car.

Check the battery voltage. If it's over 14 volts, the alternator is fine. Don't run the car long like this. If it's still ~12 volts, it's the regulator.

This duplicates the test in FSM except you are using the headlights to load the system rather than the carbon pile.
 
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