Battery losing juice... Need help!
Thread Starter
Melting Slicks
Joined: Jul 1999
Posts: 3,201
Likes: 0
From: Clifton Park NY
Battery losing juice... Need help!
Hello All,
Here's my new problem: my battery is constantly losing charge, and even with the car running the ammeter points slightly to the negative side. Could the alternator be going bad? :confused:
I need help troubleshooting this, since I don't know where to start!
Thanks in advance!
-Pedro
Here's my new problem: my battery is constantly losing charge, and even with the car running the ammeter points slightly to the negative side. Could the alternator be going bad? :confused:
I need help troubleshooting this, since I don't know where to start!
Thanks in advance!
-Pedro
Safety Car
Joined: Jun 2001
Posts: 4,004
Likes: 2
From: Severna Park Md
Re: Battery losing juice... Need help! (Pedro'74)
Im not sure but i believe the 74's have an internal regulator alternator. Therefore if your ammeter is constantly reading in the negitive, most likely its a problem inside your alternator. Check to make sure your belt is on and in good shape and that it is not too loose. I've seen loose belts cause discharging conditions in otherwise functioning charging systems. Also check for loose wires at alt and battery. After these basic things have been varified as ok, the next step would be bench testing your alt. If you take it off the car and take it down to a local parts store, most of them have bench testing equipment and can tell you the condition of you alt.
Thread Starter
Melting Slicks
Joined: Jul 1999
Posts: 3,201
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From: Clifton Park NY
Re: Battery losing juice... Need help! (Jvette73)
Thanks, John! That will give me a point where to start! Checking the alternator belt tension was my first thought, since I have been messing with the alternator (I removed it to paint the brackets). That will be the first thing I'll do tomorrow. Then I'll try the wires, and if I have no luck, I'll take it to Autozone to be tested.
Thanks again!
-Pedro
Thanks again!
-Pedro
Racer
Joined: Jan 2000
Posts: 491
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From: florida
Re: Battery losing juice... Need help! (Pedro'74)
If you have a volt meter check for 14 volts while its running. Then turn on the headlights and make sure it stays about the same. IF your not getting around 14 volts you alternator is going bad. You did say you were messing with it also, so you should make sure the wires and connectors are okay. If your battery is going dead after just sitting for one day I would start looking for a short. lou
[Modified by lou, 1:27 AM 8/4/2001]
[Modified by lou, 1:41 AM 8/4/2001]
[Modified by lou, 1:27 AM 8/4/2001]
[Modified by lou, 1:41 AM 8/4/2001]
Race Director
Joined: Apr 1999
Posts: 10,866
Likes: 717
From: Beverly Hills/Pine Ridge Florida
Re: Battery losing juice... Need help! (lou)
If you accidently got a spark or two when you were removing or re-installing the alternator wiring...wrench slipped, etc., you might have fried a diode or two. Don't ask me how I know this. 
If it's your "original" alternator, it can be rebuilt. I personally wouldn't "mess" with a junk rebuild from AutoZone/PEP Boys, etc. Too much trouble with their rebuilt stuff. Chuck
If it's your "original" alternator, it can be rebuilt. I personally wouldn't "mess" with a junk rebuild from AutoZone/PEP Boys, etc. Too much trouble with their rebuilt stuff. Chuck
Thread Starter
Melting Slicks
Joined: Jul 1999
Posts: 3,201
Likes: 0
From: Clifton Park NY
Re: Battery losing juice... Need help! (Pedro'74)
Thanks for the responses, guys!
Seems that I know the root of the problem now. The belt was loose, so I tightened it. But it seems that the real culprit is the red wire that is connected to the alternator: as I move it, the ammeter needle goes to the positive side. Problem: the wire and nut are stuck to the terminal--they seem to be soldered or something. Other problem: the terminal is kinda loose. Don't know exactly what to do, but at least now I know what the problem is! :D
With this problem I didn't even have the opportunity to enjoy the awesome sound of the new chambered exhaust... :(
-Pedro
Seems that I know the root of the problem now. The belt was loose, so I tightened it. But it seems that the real culprit is the red wire that is connected to the alternator: as I move it, the ammeter needle goes to the positive side. Problem: the wire and nut are stuck to the terminal--they seem to be soldered or something. Other problem: the terminal is kinda loose. Don't know exactly what to do, but at least now I know what the problem is! :D
With this problem I didn't even have the opportunity to enjoy the awesome sound of the new chambered exhaust... :(
-Pedro
Thread Starter
Melting Slicks
Joined: Jul 1999
Posts: 3,201
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From: Clifton Park NY
Re: Battery losing juice... Need help! (MNJack)
The manual calls for disconnecting the battery negative cable even for jobs such as filling up the tank! :crazy:
-Pedro
[Modified by Pedro'74, 12:00 PM 8/4/2001]
-Pedro
[Modified by Pedro'74, 12:00 PM 8/4/2001]
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Drifting
Joined: Feb 2001
Posts: 1,603
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From: San Francisco, CA
Re: Battery losing juice... Need help! (Pedro'74)
I almost always disconnect the neg. cable when working on the car - even for radiator hoses and the like. I decided to start doing this after reading posts of shorts and burnt wiring harnesses due to accidents when working under the hood. These cars are difficult enough to deal with without causing problems for myself. Just my .02
Safety Car
Joined: Jun 2001
Posts: 4,004
Likes: 2
From: Severna Park Md
Re: Battery losing juice... Need help! (Pedro'74)
Heres a neat thought about loose battery connections. I was working on my jeep one day when the positive battery cable with bad insulation touched the copper oil pressure line. This line runs with the harness through the firewall. Suddenly I saw smoking and arcing comming from the harness where it goes through the firewall. I dont know how it came to be but my first reaction was to yank the positive battery cable off of the battery post. The connection was not too tight so it came right off and the arcing ceased immeadiatly. Im glad I didnt reach for my fire extinguisher because i dont thin this woulda helped. Taped a few wires and i was on my way. In this case the loose connection saved my jeep. :yesnod:
Team Owner
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From: Exiled to Richmond, VA - Finally sold my house in Murfreesboro, TN ?? Corner of "Bumf*&k and 'You've got a purdy mouth'."
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St. Jude Donor '06-'10, '13
Re: Battery losing juice... Need help! (Pedro'74)
You can buy an alternator rebuild kit at any GOOD parts store.
I rebuilt mine and it is a piece of cake.
Or you can buy a new one --- they are cheap.
I rebuilt mine and it is a piece of cake.
Or you can buy a new one --- they are cheap.
Thread Starter
Melting Slicks
Joined: Jul 1999
Posts: 3,201
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From: Clifton Park NY
Re: Battery losing juice... Need help! (BSeery)
Thanks a lot for the tips, guys!
The alternator is working as it should, provided the "BAT" wire is in a certain position. Today I drove the car a lot, and everything was working great. But I know that if that wire moves just a little bit, the battery will start to lose charge again.... Not good!
As I said before, the problem is that the "BAT" terminal is loose. Question: is the terminal screwed to the alternator case? If so, then I'm screwed too, because the damn thing is probably stripped. Or is the terminal held from the inside by a nut or something?
Off-Topic 1: my car passed the state inspection today, and it's now legally on the road! :D
Off-Topic 2: the chambered exhaust sounds GREAT! :cool:
Off-Topic 3: after driving during the whole day, in the evening I was asking myself where did all the other Corvettes go now that mine is back on the road. I had not seen a single one, and was kinda disappointed, dying to wave to another Vette. But then I saw a beautiful blue 58-60 C1, which I let make a left turn in front of me. Great wave to end in great style my first day driving my car after more than one year! :D
Thanks again!
-Pedro
The alternator is working as it should, provided the "BAT" wire is in a certain position. Today I drove the car a lot, and everything was working great. But I know that if that wire moves just a little bit, the battery will start to lose charge again.... Not good!
As I said before, the problem is that the "BAT" terminal is loose. Question: is the terminal screwed to the alternator case? If so, then I'm screwed too, because the damn thing is probably stripped. Or is the terminal held from the inside by a nut or something?
Off-Topic 1: my car passed the state inspection today, and it's now legally on the road! :D
Off-Topic 2: the chambered exhaust sounds GREAT! :cool:
Off-Topic 3: after driving during the whole day, in the evening I was asking myself where did all the other Corvettes go now that mine is back on the road. I had not seen a single one, and was kinda disappointed, dying to wave to another Vette. But then I saw a beautiful blue 58-60 C1, which I let make a left turn in front of me. Great wave to end in great style my first day driving my car after more than one year! :D
Thanks again!
-Pedro