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battery goes dead


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You should be able to see a small arc when disconnecting the Negative terminal, if any drain is there. Touch the connector to the post and see if there is any arc. That will tell you if there is anything draining the battery. <P>In order to check the voltage regulator output, first check the lamp in the "GEN" indicator then check the voltage output from the reg to the battery with a meter. Should be 12.3 to about 13.8, depending on battery condition. Generally, this is on the RED wire coming from the reg. <P>------------------<BR>George C. Thomas<BR>70 GS 455 12.teens<BR>86 GN Low 13's/ high 12's

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Actually you should get between 13.8 and 14.3 voltls when the engine is running. a FULLY charged 12 volt battery should read 12.65v open cct with no loads on it. Battery drains of over 50 miliamps can kill a battery overnight. A battery with a bad cell in it can read over 12v but when a load is applied (starting) the voltage will take a severe dump to well under 9v. Most gm's should read battery voltage over 9v. Snap-on sells a cool tool called an ammeter shunt. it can be used to measure current up to 200Amps with a digital multimeter. You take the o/p lead off your alternater and place the shunt in series between the terminal and the wire, you now measure milivolts across the two small leads and this will tell you how much current your alternator is putting out. When you start adding loads (heater fan,lights and stuff) your alternater should start increasing it output. The shunt costs $50 Canadian up here. Also easy things to check out are those silly little things like glovebox and trunk lights if you got em or other electric accessories like power trunk release solenoids.<P>Hope this helps<P>------------------<BR>Lee C.<BR>81 Electra Park Ave (350 original)<BR>83 Electra Park Ave (307 that wont die)

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Well I shoulda thought of that the belts on my 350 seem to loosen up all the time and all the belts are new. Only thing is mine squeel like crazy when they slip. The alt belt always goes looser than the ac. Pretty annoying.<P>------------------<BR>Lee C.<BR>81 Electra Park Ave (350 original)<BR>83 Electra Park Ave (307 that wont die)

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I don't want to patronize you guys but I thought I could add some tips.<BR>1. The battery is always the first thing to check when diagnosing an electrial problem.<BR>2. A good way to tell a batterys actual voltage is to turn your headlights on for a minute with the engine off. This will get rid of the "surface charge". GM boat owner is correct in that it should have 12.6 volts. If it has less than 12.0 after this test then it is basically dead.<BR>3. I wouldn't recommend making any unnecessary sparks near the battery. The fumes are explosive and as you know batteries are full of acid. Not a pretty thought.<BR>4. Another check you can do with a Volt/Ohm meter is to check if their is voltage travelling between the Neg battery post and the Neg wire attachment point on the engine. This measures the voltage traveling through the car to keep you radio memory etc. It should be very low.<BR>5. Finally you can pull fuses until the loss goes away. This will isolate which circuit has the loss. <BR>

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Justin, Check to see if all your lights go out, such as the hood light, the trunk light, the glove box light or any other light as mentioned. Also if you have modern stereo/radio installed, does the led or lcd (display) go out when the ignition is off. These are a few items that can be easily checked and could cause drainage. Also even if you have a new regulator & alt. they should be re-checked. I ran into a problem a few years back and got two bad Rebuilt Alts.<BR>I hope this helps. John Lyman Automotive Instructor/ Advisor/ BUICK

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JUSTIN, Tomsriv is correct about sparks around the battery, BUT, it's impossible to remove either terminal and not have one if there is a DRAW on the battery. Do it in the dark and you'll see some kind of draw, if it exists.<P>------------------<BR>George C. Thomas<BR>70 GS 455 12.teens<BR>86 GN Low 13's/ high 12's

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