Brand new battery drained in one day! - The 1947 - Present Chevrolet & GMC Truck Message Board Network

LiquidLight · 03-08-2005, 07:09 PM

I just replaced the battery in my 67 chevy 4x4. I thought it had given up the ghost, it was over 5 years old. Anyways, i bought a brand new battery...800 cold crankin and 1000 crankin amps. Truck fired up and got me around great all day yesterday... Today, the battery is DEAD. I left no accesories on at all. What could be doing this to my batterys? I suppose my 5 year old battery i took out was actually still working at this point. Please help, im lost on where to begin to troubleshoot this!

CHEVYE · 03-08-2005, 07:22 PM

pull the pos. wire from the batt. while it is running. if it still runs your alt. should be good. if it stalls right out then your truck has been running on the batt. alone and you should pick up a new alt.

vfrdude · 03-08-2005, 07:26 PM

Don't do the disconnect battery cable while the engine is running, it will damage the alternator. This was a valid test back in the day of generators.
I had a friend that had the same symptoms. He finally took it to a auto electric place. They found the alternator had bad diode in it. I would have the alternator and it's components checked out, if you haven't don so already.

68gmcdually · 03-08-2005, 07:31 PM

Any automotive shop should have what I have. It is a electronic load tester that tests the battery, then you turn on the headlights, shut them off. Then start the motor and it checks the alternator. Very cool, but very pricey.

shifty · 03-08-2005, 07:36 PM

My dad always told me the best way to test an alternator is this:

Get a cheap multimeter from Home Depot (if you don't have one already)

Set your multimeter to DC voltage and put the black wire to a solid ground and the red wire to the power output of the alternator.

Crank the engine. You should read 12v-14v from the alternator. If not, the alternator is dead.

Keep the multimeter on the power output of the alternator while somebody else turns on the headlights and pushes the breaks and turns the radio on (this will introduce load to the alternator). Make sure the power output of the alternator doesn't drop drastically.

This isn't the most professional way to test, but it will show you whether your alternator is keeping up properly.

vfrdude · 03-08-2005, 07:46 PM

We did this test with my friends truck. It checked out OK. An alternator can have a bad diode, and still put out a charge. That's what had us stumped.

LiquidLight · 03-08-2005, 07:51 PM

I tested the alternator a month ago with one of those 12.99 alternator testers from walmart.. Maybe thats what threw it off too,,it read my alternator was ok... But, perhaps the charge wasnt really significant? Hmmm.

shifty · 03-08-2005, 08:03 PM

How much is a rebuild kit for an alternator? I would think it wouldn't, but ... I don't know if a rebuild kit would replace the diode(s) in an alternator. I don't know if alternators use diodes in the same way that most other electronics do.

cableguy0 · 03-08-2005, 08:09 PM

i would bet if you threw a new alternator and regulator at it total cost probably 40 bucks for rebuilt alternator and new regulator your problem would go away

CHEVYE · 03-08-2005, 08:12 PM

it wouldn`t cost anymore to just buy a lifetime warr alt. rather than rebuild it.

LiquidLight · 03-08-2005, 08:21 PM

Yeah i priced autozone a few minutes ago...looks like its going to be a quick fix. Ill get my alternator tested first just in case. Im not good at electrical problems,,i guess what i was thinking is that even if the alternator wasnt working i couldnt fathom the battery draining in one day. I guess its very easy to drain a battery with out the recharge eh?

cableguy0 · 03-08-2005, 08:22 PM

yup your lucky it ran as long as it did without the alternator working if thats problem. the alternator runs everything after the vehicle is started the batterys only job is to get it started

LiquidLight · 03-08-2005, 08:44 PM

Hehe, that kinda comical after i fixed it i was jammin out on the radio all over town.

ty for all the help guys!

shifty · 03-08-2005, 08:48 PM

That might have been what killed it

LiquidLight · 03-08-2005, 09:14 PM

Haha!!

Im probably going to get flamed for this, but where is the voltage regulator located? I think ill pick one up as well.

cableguy0 · 03-08-2005, 09:17 PM

its on the core support on the drivers side. look between the headlight and the radiator

Dean23 · 03-08-2005, 09:57 PM

Using a multimeter to tesy an alternator isnt a valid test. It just check voltage, you also need to check amp output. an alternator can be putting out 13 volts but only 10-20 amps. Those amps wont recharge your battery. All the 13 volts telss you is that your voltage reg is working.

LiquidLight · 03-08-2005, 10:13 PM

Damn, this forum rocks, ty for all the help!!!!

LiquidLight · 03-08-2005, 11:01 PM

I was just reading the post with the other guy with battery problems. They suggested the horn button may cause a draw. Well, my turn signal lever is broken right now, and sometimes if it wabbles right it makes the horn blow. Could this be related? Or would that be more like a slow draw and not drain it overnight?

**VetteVet** · 03-08-2005, 11:49 PM

I had this same problem on my 1980 Monte Carlo and I went and got a new battery for it and the next day (same thing ) brand new diehard dead. So I had the wife take the car in after she got a jump and they supposedly checked out the system and said the alternator was ok. They replaced the new die hard with another new diehard and guess what ? The next day another dead battery. I decided that Sears didn't know squat about trouble shooting so I started looking for the drain. First I started the car and pulled the positive battery cable off, and the motor kept running. I knew the alternator was charging so I put the cable back on and shut off the engine. I have done this plenty of times and never harmed an alternator. The thing to keep in mind is not to rev the engine or the output from the alternator will over charge any thing that's loaded. If you don't believe me just turn on the lights and rev the engine with the battery cable off. Poof LOL. Vfrdude is right about this check on the newer vehicles because a voltage surge could kill a computer or any of the sensors on these cars where 1.5 to 5 volts is their operating range. Don"t do it.
I checked the output at the alternator and I had a full 14.5 volts, Perfect.
I pulled the negative cable off the battery and tapped it on the post and I had a spark. Not big but more than it should with all the lights and normal stuff off. I back traced the wiring and it always led to the red wire on the alternator output terminal. I pulled that wire off and the spark at the battery went away. This can be substituted by a small light as the thread in the FAQs
suggests. I knew then that the diode in the alternator was bad. To make a long story shorter I pulled the alternator off and replaced that diode and it worked great for at least 10 more years.
The amperage output of the alternator is only going to be as large as the load on it plus the amperage required to keep the battery charged. The battery acts as a capaciter to store excess voltage and surges that the alternator puts out and to provide a smooth current flow to the system draw.
I hope I haven't bored you too much.
Vettevet

**VetteVet** · 03-08-2005, 11:55 PM

I though we were sure that your alternator was bad and not charging the battery. Or is it? There's too many gremlins in these trucks lately. It must be a Ford conspiracy.
LOL

bowhunter · 03-09-2005, 01:22 AM

Here's a quick way to see if you have a draw. Use either an amp meter or a 12v test light. Disconnect the positive battery cable and touch it to the negative cable. That will discharge any capacitors that may still have a charge. Then put one lead of the amp meter to the positive battery post and the other to the positive battery cable (in series). The amp meter should read less than .3 amps. If it has more you have a draw. Using a 12v test light do the procedure above (one end of the test light to + post other end to + cable (in series)) if the light is on you have a draw. Wanna find the draw? Start pulling fuses until the light or amps go away...viola you now know where to start looking.

03-08-2005, 07:09 PM	#1
LiquidLight Registered User Join Date: Sep 2004 Location: Luray, Virginia Posts: 17	Brand new battery drained in one day! I just replaced the battery in my 67 chevy 4x4. I thought it had given up the ghost, it was over 5 years old. Anyways, i bought a brand new battery...800 cold crankin and 1000 crankin amps. Truck fired up and got me around great all day yesterday... Today, the battery is DEAD. I left no accesories on at all. What could be doing this to my batterys? I suppose my 5 year old battery i took out was actually still working at this point. Please help, im lost on where to begin to troubleshoot this!

03-08-2005, 07:22 PM	#2
CHEVYE my gas saver Join Date: Sep 2003 Location: Clarksville, TN Posts: 2,046	pull the pos. wire from the batt. while it is running. if it still runs your alt. should be good. if it stalls right out then your truck has been running on the batt. alone and you should pick up a new alt. __________________ 85' SWB, 4.3/TH350, getting ready for paint 84`SWB, 462ci./TH400, cowl hood, 15" billet spec., flows, blazer buckets/console, flat black 71`SWB, project ebay feedback

03-08-2005, 07:26 PM	#3
vfrdude Registered User Join Date: May 2002 Location: Oakley, Ca. USA Posts: 137	Don't do the disconnect battery cable while the engine is running, it will damage the alternator. This was a valid test back in the day of generators. I had a friend that had the same symptoms. He finally took it to a auto electric place. They found the alternator had bad diode in it. I would have the alternator and it's components checked out, if you haven't don so already. __________________ Rudy Fierros '95 Honda VFR750F Used to have a '71 Chevy Stepside, Guards Red, Lowered 4" rear, 3" front, White Oak bed wood, 700R4 w/373 gears until some low life stole it!

03-08-2005, 07:31 PM	#4
68gmcdually Registered User Join Date: Feb 2004 Location: Fenelon Falls, ON Canada Posts: 1,455	Any automotive shop should have what I have. It is a electronic load tester that tests the battery, then you turn on the headlights, shut them off. Then start the motor and it checks the alternator. Very cool, but very pricey. __________________ James Bellwood 1968 930 Extend-A-Cab Dually 5.7l, 5 speed,

03-08-2005, 07:36 PM	#5
shifty Questionable Join Date: Mar 2005 Location: Atlanta Posts: 13,376	My dad always told me the best way to test an alternator is this: Get a cheap multimeter from Home Depot (if you don't have one already) Set your multimeter to DC voltage and put the black wire to a solid ground and the red wire to the power output of the alternator. Crank the engine. You should read 12v-14v from the alternator. If not, the alternator is dead. Keep the multimeter on the power output of the alternator while somebody else turns on the headlights and pushes the breaks and turns the radio on (this will introduce load to the alternator). Make sure the power output of the alternator doesn't drop drastically. This isn't the most professional way to test, but it will show you whether your alternator is keeping up properly. __________________ If I've got anything up for grabs, it'll be here: 7-hole gauge cluster for a 67-72 p/u FREE (link) I can't check the forum daily. If I don't reply to you within 24 hours, drop me a PM! I'm (hopefully) still alive and will reply faster to a PM.

03-08-2005, 07:46 PM	#6
vfrdude Registered User Join Date: May 2002 Location: Oakley, Ca. USA Posts: 137	We did this test with my friends truck. It checked out OK. An alternator can have a bad diode, and still put out a charge. That's what had us stumped. __________________ Rudy Fierros '95 Honda VFR750F Used to have a '71 Chevy Stepside, Guards Red, Lowered 4" rear, 3" front, White Oak bed wood, 700R4 w/373 gears until some low life stole it!

03-08-2005, 07:51 PM	#7
LiquidLight Registered User Join Date: Sep 2004 Location: Luray, Virginia Posts: 17	I tested the alternator a month ago with one of those 12.99 alternator testers from walmart.. Maybe thats what threw it off too,,it read my alternator was ok... But, perhaps the charge wasnt really significant? Hmmm.

03-08-2005, 08:03 PM	#8
shifty Questionable Join Date: Mar 2005 Location: Atlanta Posts: 13,376	How much is a rebuild kit for an alternator? I would think it wouldn't, but ... I don't know if a rebuild kit would replace the diode(s) in an alternator. I don't know if alternators use diodes in the same way that most other electronics do. __________________ If I've got anything up for grabs, it'll be here: 7-hole gauge cluster for a 67-72 p/u FREE (link) I can't check the forum daily. If I don't reply to you within 24 hours, drop me a PM! I'm (hopefully) still alive and will reply faster to a PM.

03-08-2005, 08:09 PM	#9
cableguy0 Senior Member Join Date: Apr 2000 Location: Delta,Pa Posts: 14,950	i would bet if you threw a new alternator and regulator at it total cost probably 40 bucks for rebuilt alternator and new regulator your problem would go away __________________ Owner of North Point Car Care in Dundalk Md. We specialize in custom exhaust on both modern and classic vehicles. We are a full service auto shop from classics to modern vehicles. Feel free to contact me with questions. I will give a 10% discount to any board member.

03-08-2005, 08:12 PM	#10
CHEVYE my gas saver Join Date: Sep 2003 Location: Clarksville, TN Posts: 2,046	it wouldn`t cost anymore to just buy a lifetime warr alt. rather than rebuild it. __________________ 85' SWB, 4.3/TH350, getting ready for paint 84`SWB, 462ci./TH400, cowl hood, 15" billet spec., flows, blazer buckets/console, flat black 71`SWB, project ebay feedback

03-08-2005, 08:21 PM	#11
LiquidLight Registered User Join Date: Sep 2004 Location: Luray, Virginia Posts: 17	Yeah i priced autozone a few minutes ago...looks like its going to be a quick fix. Ill get my alternator tested first just in case. Im not good at electrical problems,,i guess what i was thinking is that even if the alternator wasnt working i couldnt fathom the battery draining in one day. I guess its very easy to drain a battery with out the recharge eh?

03-08-2005, 08:22 PM	#12
cableguy0 Senior Member Join Date: Apr 2000 Location: Delta,Pa Posts: 14,950	yup your lucky it ran as long as it did without the alternator working if thats problem. the alternator runs everything after the vehicle is started the batterys only job is to get it started __________________ Owner of North Point Car Care in Dundalk Md. We specialize in custom exhaust on both modern and classic vehicles. We are a full service auto shop from classics to modern vehicles. Feel free to contact me with questions. I will give a 10% discount to any board member.

03-08-2005, 08:44 PM	#13
LiquidLight Registered User Join Date: Sep 2004 Location: Luray, Virginia Posts: 17	Hehe, that kinda comical after i fixed it i was jammin out on the radio all over town. ty for all the help guys!

03-08-2005, 08:48 PM	#14
shifty Questionable Join Date: Mar 2005 Location: Atlanta Posts: 13,376	That might have been what killed it __________________ If I've got anything up for grabs, it'll be here: 7-hole gauge cluster for a 67-72 p/u FREE (link) I can't check the forum daily. If I don't reply to you within 24 hours, drop me a PM! I'm (hopefully) still alive and will reply faster to a PM.

03-08-2005, 09:14 PM	#15
LiquidLight Registered User Join Date: Sep 2004 Location: Luray, Virginia Posts: 17	Haha!! Im probably going to get flamed for this, but where is the voltage regulator located? I think ill pick one up as well.



Register or Log In To remove these advertisements.

03-08-2005, 09:17 PM	#16
cableguy0 Senior Member Join Date: Apr 2000 Location: Delta,Pa Posts: 14,950	its on the core support on the drivers side. look between the headlight and the radiator __________________ Owner of North Point Car Care in Dundalk Md. We specialize in custom exhaust on both modern and classic vehicles. We are a full service auto shop from classics to modern vehicles. Feel free to contact me with questions. I will give a 10% discount to any board member.

03-08-2005, 09:57 PM	#17
Dean23 68cst_ss490 Join Date: May 2001 Location: edmonton,canada Posts: 1,363	Using a multimeter to tesy an alternator isnt a valid test. It just check voltage, you also need to check amp output. an alternator can be putting out 13 volts but only 10-20 amps. Those amps wont recharge your battery. All the 13 volts telss you is that your voltage reg is working. __________________ Dean edmonton,canada a winter wonderland 2005 Chevrolet Avalanche LT cold air intake, performance exhaust, Comp cams cam, jba shorty ceramic headers. http://www.cardomain.com/ride/3090973

03-08-2005, 10:13 PM	#18
LiquidLight Registered User Join Date: Sep 2004 Location: Luray, Virginia Posts: 17	Damn, this forum rocks, ty for all the help!!!!

03-08-2005, 11:01 PM	#19
LiquidLight Registered User Join Date: Sep 2004 Location: Luray, Virginia Posts: 17	I was just reading the post with the other guy with battery problems. They suggested the horn button may cause a draw. Well, my turn signal lever is broken right now, and sometimes if it wabbles right it makes the horn blow. Could this be related? Or would that be more like a slow draw and not drain it overnight?

03-08-2005, 11:49 PM	#20
VetteVet Msgt USAF Ret Join Date: Jan 2005 Location: Kalamazoo, Michigan Posts: 8,707	battery dead I had this same problem on my 1980 Monte Carlo and I went and got a new battery for it and the next day (same thing ) brand new diehard dead. So I had the wife take the car in after she got a jump and they supposedly checked out the system and said the alternator was ok. They replaced the new die hard with another new diehard and guess what ? The next day another dead battery. I decided that Sears didn't know squat about trouble shooting so I started looking for the drain. First I started the car and pulled the positive battery cable off, and the motor kept running. I knew the alternator was charging so I put the cable back on and shut off the engine. I have done this plenty of times and never harmed an alternator. The thing to keep in mind is not to rev the engine or the output from the alternator will over charge any thing that's loaded. If you don't believe me just turn on the lights and rev the engine with the battery cable off. Poof LOL. Vfrdude is right about this check on the newer vehicles because a voltage surge could kill a computer or any of the sensors on these cars where 1.5 to 5 volts is their operating range. Don"t do it. I checked the output at the alternator and I had a full 14.5 volts, Perfect. I pulled the negative cable off the battery and tapped it on the post and I had a spark. Not big but more than it should with all the lights and normal stuff off. I back traced the wiring and it always led to the red wire on the alternator output terminal. I pulled that wire off and the spark at the battery went away. This can be substituted by a small light as the thread in the FAQs suggests. I knew then that the diode in the alternator was bad. To make a long story shorter I pulled the alternator off and replaced that diode and it worked great for at least 10 more years. The amperage output of the alternator is only going to be as large as the load on it plus the amperage required to keep the battery charged. The battery acts as a capaciter to store excess voltage and surges that the alternator puts out and to provide a smooth current flow to the system draw. I hope I haven't bored you too much. Vettevet __________________ VetteVet metallic green 67 stepside 74 corvette convertible 1965 Harley sportster 1995 Harley wide glide Growing old is hell, but it beats the alternative.

03-08-2005, 11:55 PM	#21
VetteVet Msgt USAF Ret Join Date: Jan 2005 Location: Kalamazoo, Michigan Posts: 8,707	I though we were sure that your alternator was bad and not charging the battery. Or is it? There's too many gremlins in these trucks lately. It must be a Ford conspiracy. LOL __________________ VetteVet metallic green 67 stepside 74 corvette convertible 1965 Harley sportster 1995 Harley wide glide Growing old is hell, but it beats the alternative.

03-09-2005, 01:22 AM	#22
bowhunter Registered User Join Date: Oct 2004 Location: Moore, Ok. Posts: 17	Here's a quick way to see if you have a draw. Use either an amp meter or a 12v test light. Disconnect the positive battery cable and touch it to the negative cable. That will discharge any capacitors that may still have a charge. Then put one lead of the amp meter to the positive battery post and the other to the positive battery cable (in series). The amp meter should read less than .3 amps. If it has more you have a draw. Using a 12v test light do the procedure above (one end of the test light to + post other end to + cable (in series)) if the light is on you have a draw. Wanna find the draw? Start pulling fuses until the light or amps go away...viola you now know where to start looking.

Register or Log In To remove these advertisements.