flat battery

[bigtow]

my battery has just given up the ghost all of a sudden the hydrometeris showing green and the charge meter is showing 13 volts but the starter just turns once then clicks if you put a boost pack on it will start at once. if i put a multi meter on the battery it shows 12.3 volts with the key off as soon as you turn the key on bot not to start it drops to 10.2 volts is it my battery or altenator i have not been able to check the out put with the car running any clues? ps this car is my daily driver so i need help quick if poss

[Black97]

How old's the battery?

Had same symptoms recently on two of my cars and both times I had to buy a new battery. One was only 1 1/2 years old.

[bigtow]

re flat bat

i do not know how old the battery is its just strange that the hydrometer is still green. go corvttes have the same batery as i an get one of thoe tomoro?

[Black97]

Anyhow, charge the battery for several hours and then hook it up. If the same thing happens again, I would say it is shut.

[Jeff_in_Atl]

I would jump start it then disconnect the battery. Rev it to like 1500 and turn on the lights and the A/C on max. If it doesn't die, it's the battery. If it does, it's the alternator.

[wolfdogs]

Originally posted by Jeff 95 Z28
I would jump start it then disconnect the battery. Rev it to like 1500 and turn on the lights and the A/C on max. If it doesn't die, it's the battery. If it does, it's the alternator.

alternator-ed cars wont run without input from a battery...unlike a car with a generator.... they need the current input to the stator in the alternator...........thats why you cant push/jump start a car with an alternator........what are you talking about broh?

[Jeff_in_Atl]

Originally posted by wolfman
alternator-ed cars wont run without input from a battery...unlike a car with a generator.... they need the current input to the stator in the alternator...........thats why you cant push/jump start a car with an alternator........what are you talking about broh?

Come on man, I'm not that old. I've never had a car with a generator.

Not true. Once the alternator is spinning, it energizes the entire electrical system. If you run the output of the alternator to the positive input to the regulator, you can spin it and it will make juice (and grounding the negative to the case.).

And just to be sure, I started my car, disconnected the battery and it ran fine. I've load tested alternators like this for years.

[rufrider76]

i had the same thing happen to me this weekend on my bonneville. it is the battery. do you have a large stereo in you car. sometimes when you deep cycle a battery so many times it will ruin it. Mine i could hook to the battery charger and it would take the charge. as soon as i hit the key it would drop to around 6 volts and start charging agian. i was luckily had my t/a apart and a fresh battery setting on the floor in my garage so i hooked it up and it was all good

[Spades95formula]

someone told me that if you diconect the battery while on it could " spike" the system . dont know if thats true or not though

[bigtow]

new battery

i just fitted a new battery so i will keep i eye on it and let you know