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Discussion Starter #1
I've had my '69 for about 3 years now. 29K original car, cosmetic upkeep only. Problem is when I got it I replaced a crummy battery, didn't know how long it had been in the car, so I bought a new nice Optima. Seems like about 2 months of driving it i smelled acid. Alternator was overcharging. Changed alternator but battery seemed weakened. Replaced main battery and starter cables with new starter and got a new replacement Optima. Ran well, but one day would not start or take a charge (Battery minder). There had been no long period of inactivity, 3 days max. Got a replacement Optima and it ran well without problems for a while. Then same thing last month. Out of blue no start, Optima had 7 volts on it and a "dead cell" per the battery dealer. I replaced it with a cheaper Interstate and 70 bucks in refund. 3 weeks later in same boat. Battery dead after starting strong for 3 weeks and sitting for maybe 3 days. 1 volt reading, will not take a charge. Car has raplacement electric clock and radio, otherwise I can think of another power drain. Car will not start if jumper cables used either. Next step? I am planning a full rewiring, but want to know if this is a potentiol solution to the problem or another possibility exists.:WTF
 

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Do you have a battery disconnect switch?

After I redid my rewiring, try as I might, the battery kept going dead.. From readin your post, it seems this problem of yours occurs whenever you keep the car un-driven for a period of time...

I'm sure your problem must be different than mine, but try installing a battery disconnect switch.. (costs about 6 bucks), as an iterim, so you can atleast start er up.

It worked for me.. :)
 

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I agree with E Tar. I bought a disconnect because my battery kept dying because I hardly used the car and it had a small drain. I didn't feel like finding the problem either. Plus, it's another theft deterrent.
 

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Bad alternator or you have an open short allowing the battery to drain.

A disconnect switch might help, but will not resolve the problem.

:thumbsup:
 

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I am with Mike here. Even a small draw (less than 150 to 200 milliamps) will drain a battery quickly. Find the draw. Learn how to use an ammeter and pull fuses until you find the circuit. Most likely culprits are interior lights and a horn relay problem (if the horn doesn't work.) Clocks and properly wired radios will never kill a battery, as the draw is less than 50 milliamps.
 

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well i know your frustration i had a ford ranger that would randomly destroy a battery ..it could go for a week or so perfectly normal sometimes only a day and suddenly when i went to start it ..dead battery ..not just dead...but DEAD wouldnt hold a charge after that first drain...took the thing to several shops never traced it down ..put a on/off switch on it and never had another issue ..

..bought my 78 vette and owner descibed similar problems..already had a switch on it ..it has yet to eat a battery for me ive left it on a time or two over night when i forgot about it ...interesting thing i did find was an old Rockford Fosgate amp tucked upside down in the jack compartment it was small enough you had to literally stick your head in upside down in there to see it ..it was still hooked up to power.. it was a whopping 35 watts per channel had to have been there for years i spoke with the previous owner he never knew it was even there lol. <-- im guessing that was my drain .

i would throw a on/off switch inline till you trace the drain down if you find the issue please post ..im curious
 

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Discussion Starter #7
Drained

Well Im due a re-wire anyway so will buy a new battery, keep it on the Battery minder when in the garage even over night til then. I did re-do the interior with dynamat covering the whole tub. The driver door unterior switch dosent work, as a matter of fact its been amputated at the door and I dont know where the other end may be. It has a crappy aftermarket radio that I installed and I will be replacing that unit as well. Funny that the first year I had the vette i noticed a bunch of underdash spagetti and even would get an occaisional short from a bare wire until tracked down.
 

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Put your multimeter in ammeter mode between your + battery and the node connecting the 2 reds cables (1 for starter, 1 for everything else).

You'll be able to measure the current flowing

A car ammeter won't do the job as you're looking for milliamps

Engine stopped, key off, start removing every fuse and check for value change everytime. When you see a big drop in value then you found the cause or at least in which circuit it is
 

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Discussion Starter #9
Over charged

Bought new battery, check as 12.5 volts. Started car, ammeter now shows 16 volts charging.:thud: Replaced alternator voltage regulator. Ammeter now reads 13.5 to 14 after change when running. Think this is the fix?? Funny bit is this has happened twice in the past year with faulty voltage regulator eating batteries. Do you think this will resolve the issue? I will check the battery charge after and before dringin for the next few days to see if there is a significant charge loss when it sits or battery just craps out from damage. Thoughts? Yep, full re-wire set for next week too.
 

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I had the same problem,except my drain wasnt as fast,so i bought a battery disconect switch and it has been find for many many years now.Theres nothing wrong with putting a disconect switch,i would put one on even if there are no problems,as a matter a fact i have,anything that sits for a while i have put one on and the batterys have lasted a long time on all.Have them on my trucks,my vette and boat,well worth putting one on.Nothing negative about putting one on either except maybe you will loose your radio stations:laughing:
 

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Bought new battery, check as 12.5 volts. Started car, ammeter now shows 16 volts charging.:thud: Replaced alternator voltage regulator. Ammeter now reads 13.5 to 14 after change when running. Think this is the fix?? Funny bit is this has happened twice in the past year with faulty voltage regulator eating batteries. Do you think this will resolve the issue? I will check the battery charge after and before dringin for the next few days to see if there is a significant charge loss when it sits or battery just craps out from damage. Thoughts? Yep, full re-wire set for next week too.
It might be china made regulators :down:
 
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