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Discussion Starter · #1 ·
Hey gang,

I thought my battery was not being charged by the alternator somehow but that's not the case. It turns out the battery is being drained when I turn the car off. If I charge the battery and leave it overnight it will be toast. What could be drawing this much power from the battery (it's a new battery, too). It's a '69 Chevelle with a 350, no air, no cruise, no nothing. I've checked all lights and such and they're all turned off. I have a CD player hooked up but the only thing running on it is the clock when the car is turned off. It's been installed for a year and it's only started giving me problems recently.

Thanks.
 

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My last guess didn't do it for you?
http://www.chevelles.com/forum/Forum22/HTML/001898.html

Try:
1, Disconnect the battery.
2, Remove the forward harness wire on the horn relay. This is the one that runs up the left fender to the connector on the firewall. Take off only this wire and reattach all others. This will separate the interior of the car from everything under the hood.
3, Recharge battery and reconnect the cable(s).
4, Let sit overnight.
5, Hook up everything the next day and see what happens. Large fast battery drains are usually under the hood.
 

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Disconect the + battery cable and conect a test light between the battery and the cable. With key off the light should not light. If it does light start pulling fuses. When you pull the fuse that makes the light go out you know where to start looking.
 

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Discussion Starter · #4 ·
John,

Sorry I didn't respond to your earlier suggestion. The alternator is good and the regulator is newer (1 year old).

Thanks for the ideas, guys... I'll let you know how I make out. Ironically, my points went two days ago so I put a new set in but it's funny how bad things don't seem to happen one at a time.
 

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Is the battery new? If not, it may seem like your charging it, but in reality it will only hold a small charge wich is why you can drive them with the help of the alternator but once you shut it off, you're walking.....

We just lived this one yesterday as a matter of fact.The charger would show a full charge but if you disconnected the battery it would not even turn over the engine
 

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Hi Rolr, Make sure your ignition system is not staying hot when you turn the ignition off ... This will also kill your points ... and will certainly drain your battery quickly ... Also, feel the laternator to see if it is warm to the touch after sitting over night ...
 

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Discussion Starter · #7 ·
Hey guys - thanks for the info.

Yes the battery is new but I'm going to check first to see if it holds a charge even when it's disconnected from the car. Will know this evening...

sdtsdt,

Thanks - I will check that!
 

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Discussion Starter · #8 ·
Furthermore,

My battery was fully charged this morning when I put it in the car... I drove around the block a couple times and got out and popped the hood.

The battery had quite a bit of fluid (I assume water) leaking out. Is this normal for a fully charged battery?
 

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Discussion Starter · #10 ·
Here's where I'm at:

I disconnected the battery and ran the test light and sure enough, when the car was off the light came on. I pulled all the fuses one at a time and still the light was on. I disconnected the alternator and bang, the light went off. So then I hooked the alternator back up and disconnected the regulator and the light went off. Does this mean my regulator is shot? I bought a new regulator yesterday and put it in, then I ran the test light again with only the alternator and the regulator connected and there was still no circuit - a good sign. So I put all the fuses back and I'll probably know tonight - if the battery is dead obviously that didn't do it, but if the battery is good that must have been it.

Voltage Regulator - $25 Canadian.
 

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My first guess is the isolation Diode in the alternater letting current drain back with the engine off. These go bad when someone crosses + & - when jump starting.
 

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Discussion Starter · #12 ·
Bob,

Any way to test the isolation diode in particular without flat out spending $$ on a new alternator? I've had the alternator tested 3 times and it's come out good each time, but that just tests to see if it's charging or not.
 

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I would think any Auto Elect shop could check it. If you have a Alt. light on the dash it will stay on very dim with the switch off if the diode is bad, It is hard to see the small drain with gauges.
 

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Discussion Starter · #15 ·
Hey guys,

It's three days later now since I swapped regulators (external) and it started up good this morning - first time I started it since Sunday. It usually only took one day of sitting to completely kill the battery so I have to assume the regulator was the problem, but I'm definitely keeping my fingers crossed.
 
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