what could drain a battery while the car is running?
Thread Starter
Registered User
Joined: Sep 2001
Posts: 903
From: boxboro, MA, USA
Originally posted by shoebox
It is not getting enough power to keep it operated, so it engages and releases rapidly.
Take the alt and get it load tested. No more guessing, wondering, theorizing, just do it.
Plus, with all this messing around, you may have wasted the battery, too.
It is not getting enough power to keep it operated, so it engages and releases rapidly.
Take the alt and get it load tested. No more guessing, wondering, theorizing, just do it.
Plus, with all this messing around, you may have wasted the battery, too.
brian
Registered User
Joined: Feb 2003
Posts: 1,553
From: San Antonio, Texas
I mean a normal 6 cell battery only produces 12 volts
there are spring-loaded brushes that ride on a commutator
Wtih all those amps flowing from the alt through those brushes, lots of arcing happens and it wears down either the contacts or the springs of the brushes. Usually the brushes are what cause most alternator problems because they wear out first.
As I tried to tell you before, you probably have a bad voltage regulator. That is what decided how much exiter voltage to put to the brushes, and through the rotor, which determines how much the alternator puts out. You can replace it if you want to, or just replace the friggin alternator.
Registered User
Joined: Apr 2002
Posts: 480
From: Lincoln, NE, USA
I have no doubt in my mind that you have an alternator problem. Nothing could be really draining the battery while the car is running because that would be a 140+ amp drain and you would notice a ton of fuses being blown.
Your alternator runs your accessories while the car is running and the battery only helps when the alternator cannot supply enough voltage to the accessories. The battery is basically just there to provide amperage to the starter motor to start the car and to backup the alternator. First though, I would make sure that you have your terminal on the alternator tight. If you do, take the thing off the car (4 bolts or so) and just get the thing load tested.
Just because you have a new alternator means nothing. Most of the ones you buy from a store are just rebuilt ones, and anytime you deal with rebuilds, you deal with human error, which happens ALL THE TIME with the rebuilt alternators.
Just my .02
Your alternator runs your accessories while the car is running and the battery only helps when the alternator cannot supply enough voltage to the accessories. The battery is basically just there to provide amperage to the starter motor to start the car and to backup the alternator. First though, I would make sure that you have your terminal on the alternator tight. If you do, take the thing off the car (4 bolts or so) and just get the thing load tested.
Just because you have a new alternator means nothing. Most of the ones you buy from a store are just rebuilt ones, and anytime you deal with rebuilds, you deal with human error, which happens ALL THE TIME with the rebuilt alternators.
Just my .02
Thread Starter
Registered User
Joined: Sep 2001
Posts: 903
From: boxboro, MA, USA
yeah, the thing is its a 200 amp one also, so a 100 amp draw or more is pretty damn huge. ill pull it on saturday or maybe friday night (car is at home, i am at relatives) and get it load tested and see what happens. ill probably take it to sears. thanks for teh help guys!
brian
brian
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Joined: Jun 2002
Posts: 117
From: Washington, PA
Thanks for all the tips guys...It actually above freezing today so, im going to go down in the garage and check it out. FWIW...i am also on my 3rd battery. The last one was the BEST EXIDE BATTERY i could get my hands on. Ill keep you all updated when i figure it out. I too am gonna take my NEW alternator and get it tested and I guess I might as well get another battery while im at it. Is OPTIMA supposed to be Kick ***? Thanks
Registered User
Joined: Jun 2002
Posts: 117
From: Washington, PA
Originally posted by 12sec97Z28
n20TransAmLT1: That was my situation exatly. Intermittently wouldn't start. Tried to test, and the battery read full charge.... just like it's supposed to. I ended up looking like an idiot and bringing it to the dealership so they can tell me that the battery will not pass a load test. it read fine under no load, but couldn't handle a load for anything. So I bought an Optima Red Top(overkill, but it looks NICE under there) and problem was solved.
When it doesn't want to start does the whole system just shut down when you turn the key to the on position? That's what mine did. Get a new battery and clean up the terminals really well.
P.S.- I thought about a ground being loose too, and i wasted my time getting under the car to check. Nothing. And all the ones behind the coil were tight too. Anyway, I hope that helps. Later.
n20TransAmLT1: That was my situation exatly. Intermittently wouldn't start. Tried to test, and the battery read full charge.... just like it's supposed to. I ended up looking like an idiot and bringing it to the dealership so they can tell me that the battery will not pass a load test. it read fine under no load, but couldn't handle a load for anything. So I bought an Optima Red Top(overkill, but it looks NICE under there) and problem was solved.
When it doesn't want to start does the whole system just shut down when you turn the key to the on position? That's what mine did. Get a new battery and clean up the terminals really well.
P.S.- I thought about a ground being loose too, and i wasted my time getting under the car to check. Nothing. And all the ones behind the coil were tight too. Anyway, I hope that helps. Later.
Registered User
Joined: Nov 2002
Posts: 422
From: Katy, TX
Is OPTIMA supposed to be Kick ***?
Yes. Most are made for large stereo systems in a standalone (aka deep cycle use. The expected lifetime on them, I believe, is 7-10 years. I've only had mine for like 2 months though, so I guess i'll just see.
Yes. Most are made for large stereo systems in a standalone (aka deep cycle use. The expected lifetime on them, I believe, is 7-10 years. I've only had mine for like 2 months though, so I guess i'll just see.
Registered User
Joined: Jun 2002
Posts: 117
From: Washington, PA
Originally posted by robob
n2oTransAmLT1 I may have an answer for you. You say you had your alternator replaced. Check the wiring from the alternator to see that the positive lead is not hitting the serpentine belt. It may have been mis-routed in front of the belt when it was replaced and is hitting the belt. It happened to me when I had roller rockers installed and the alternator was removed. The "mechanic" did not route the wire behind the belt and the belt cut into the cable causing the 4th of July to come early.
n2oTransAmLT1 I may have an answer for you. You say you had your alternator replaced. Check the wiring from the alternator to see that the positive lead is not hitting the serpentine belt. It may have been mis-routed in front of the belt when it was replaced and is hitting the belt. It happened to me when I had roller rockers installed and the alternator was removed. The "mechanic" did not route the wire behind the belt and the belt cut into the cable causing the 4th of July to come early.
HOLY ****!!!!! Thanks Sooo Much man for the info. You have been the biggest help. This was the worst problem since last summer...i hardly even drove my beast because of it. Anyhow, i read your post about 30 min ago...went into the garage, crawled under the car. And, Walla.....both of my battery cabels were totally naked where they passed by the bottom pulley. The belt/pulley striped all the coating/sleeve whatever you want to call it off the wires. No wonder i was hearing an electric chair sound. They were touching each other. That would also explain the crazy lights, and the battery being drained. Thanks again soo much. I feel like a new man again...for some reason. Love this board. Later!
Thread Starter
Registered User
Joined: Sep 2001
Posts: 903
From: boxboro, MA, USA
got alternator load tested (finally)
well, took it to autozone and had it load tested. read 14.4 volts or right about. i asked him what the tester spins at and he said probably 1000 or more rpms, and at that speed the alternator is fine in the car. its only at 700 rpms (idle for me) that there is problems. so i guess getting it tested didnt really show me anything i didnt know. Tom@mr. alternator told me to just send it back, which i will probably do anyways, but does this help you guys eliminate or add potential solutions to my problem (aside from sending it back)?
thanks
brian
thanks
brian
Registered User
Joined: Feb 2003
Posts: 1,553
From: San Antonio, Texas
Why did you ttt this again? The last thing you said was the alternator's going back. That is what me, and many others told you to do from the begening. Did you get the new alternator on there yet? I see no need to put this to the top of the forum anymore, especially with no update telling us whether our advice helped out.
Thread Starter
Registered User
Joined: Sep 2001
Posts: 903
From: boxboro, MA, USA
the reason i TT'd was because it pulled absolutely fine on the load tester. i was hoping that somebody might have another idea besides alternator that could be causing this, as im expecting to get the alternator back with Tom saying its a-ok, then i have to examine other avenues. though if i had known it would upset someone so much i wouldnt have done it 
brian
brian
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Joined: Nov 2001
Posts: 719
From: Summerfield, NC USA
just got out of the garage and degreased. I ran all over the motor trying to find the draw. when i first connect I got a 285 mA draw. After all the caps and memory chips got up to speed it dropped down to about 40mA. Alternator pulled 14 mA, tach memory pulled about 13mA, then there was brakes, digital dash, etc that pulled the remaining.
I don't think a 40mA draw is much at all. It's probably due to all the starting and not charging the motor that has caused this. I've got the alt and battery pulled and going to have both checked again tomorrow.
good luck with yours.
I don't think a 40mA draw is much at all. It's probably due to all the starting and not charging the motor that has caused this. I've got the alt and battery pulled and going to have both checked again tomorrow.
good luck with yours.