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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Oct 2009 Posts: 426 Shop Shark | | Shop Shark Joined: Oct 2009 Posts: 426 | I have replaced the battery, all wiring, voltage regulator, alternator, points/condensor, main battery cables.....truck has been running fine, and now I have a dead battery. All swithces are turned off, truck runs fine when jumped...will re start fine. Come back out in morning and the battery is dead. Could the ignition possibly be going bad? Im stumped as everything has been replaced, and I have had the battery and alternator rechecked. They operate fine. | | | | | Joined: Jun 2009 Posts: 2,201 Shop Shark | | Shop Shark Joined: Jun 2009 Posts: 2,201 | Take your battery to the parts store for a charge and test. While you are there get a multimeter to test the rest of the system with. | | | | | Joined: Apr 2009 Posts: 554 'Bolter | | 'Bolter Joined: Apr 2009 Posts: 554 | If you have a meter disconnect the positive battery cable and with the meter between it and the battery see if there is a current draw with everything shut off. If there is, and it sounds like that may be happening, you can just start disconnecting the wiring from one item at a time and see when the current draw stops.
Chuck | | | | | Joined: Feb 2004 Posts: 29,777 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,777 | The most common problem is a low-current leak in an alternator rectifier diode. Try disconnecting the big charging lead at the back of the alternator before you park the vehicle overnight and see if the battery stays charged. It takes a pretty sharp technician to find that problem, and most of the mouth-breather counter people at the parts stores don't know how to check an alternator properly. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
| | | | | Joined: Oct 2009 Posts: 426 Shop Shark | | Shop Shark Joined: Oct 2009 Posts: 426 | Would the selonoid or ignition be a problem? Ill check to see if there is a draw 1st, but was just wondering. I have a voltmeter. I went out yesterday and hooked up the jumper cables and got in the truck...like 30 sec, fired right up, didn't have to wait to charge. Ran the truck at idle til she warmed up, ran her at 2000 for a few min to try and charge the battery, shut her off and nothing. What would cause a draw that would drain it that fast. If it were the rectifier diode, what is the fix for that? The alternator has maybe 45min of run time. I have the original 230L6 in the truck, stock wiring and a 63amp alt. ***Also...noticed that the amp gauge didn't move yesterday either. If the gauge has "blown" would that cause any interference in the battery recharging? I have all the manuals and literature that a man could own for a 63, but this one is ringing my neck.
Last edited by jon1963; 08/18/2011 2:17 PM.
| | | | | Joined: Feb 2004 Posts: 29,777 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,777 | An alternator will not "recharge" a battery unless you run it for several hours, not minutes. What is the terminal voltage at the battery posts while the engine is running, and what is the specific gravity of the battery acid? I'd suggest hooking up a low-rate battery charge overnight, maybe 10 amps or so, then checking the specific gravity of all the battery cells after several hours of real charging. They should be between 1.265 and 1.300, and all the cells should test within 15 to 25 points of each other. Once the gravity is up and close to equal, do a high-rate discharge test where the battery is loaded to 1/2 its cold cranking amp rate for 15 seconds. At the end of the 15 second test, with the load still applied, the terminal voltage should be 9.6 volts or more. Until you have done ALL of these tests and completed them successfully, you don't know if the battery is good or not. Once you have established that the battery is good beyond any doubt, then you can move on to checking the alternator and the rest of the circuit. Test one thing at a time. The shotgun approach accomplishes nothing, and just frustrates you.
If you're unable or unwilling to do the right type of testing, let a professional take over. You're wasting your time otherwise. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
| | | | | Joined: Oct 2009 Posts: 426 Shop Shark | | Shop Shark Joined: Oct 2009 Posts: 426 | I appreciate all the input. Ive got to get a battery charger today, but I will let you know the progress. | | | | | Joined: Aug 2009 Posts: 295 Shop Shark | | Shop Shark Joined: Aug 2009 Posts: 295 | You have done so much that you are totally lost and confused.
You are now grasping at straws and are starting to easter egg ie throw parts and money at the problem
1. PROBLEM STATEMENT Battery discharges overnite Possible problem bad battery (shorted cell) Or you have something in circuitry draining battery,
SOLUTION replace battery with one you KNOW is good ie from another vehicle. Charge the bad one and check gravities if you can.
IF that does not help then install an ammeter or lite bulb in series with battery. IF lite lites and KEY OFF then you ahve something draining battery start by pulling fuses ONE at a time and checking lite. When it goes off you know your problem circuit. Now check each load on circuit.
Dan Bentler
| | | | | Joined: Oct 2009 Posts: 426 Shop Shark | | Shop Shark Joined: Oct 2009 Posts: 426 | I have an ammeter (the factory gauge), which seems to now not be working. I have a replacement that I will install. The problem with the battery swap is that my other two vehicles have side posts w/screws and my truck is top post. I have to get a battery charger 1st. The battery is new, well 2weeks old. Ive had it checked at two places including a place that only services batteries (batteries plus. The truck has run absolutely fine for months, had a new alternator that the back bearing fell apart in, got another installed...and now can't get the battery to hold a charge unless its running. When shut off and try to restart...get a umph, turns about 1/2 way over and then...and nothing. | | | | | Joined: Jun 2009 Posts: 2,201 Shop Shark | | Shop Shark Joined: Jun 2009 Posts: 2,201 | starting to sound to me that your alternator is not charging as HotrodLincoln suggested. The amp gauge will not drain the battery, it merely monitors the flow of electricity and the fact that it does not indicate anything tells you that you have a problem with the charging system. | | | | | Joined: Apr 2011 Posts: 106 Wrench Fetcher | | Wrench Fetcher Joined: Apr 2011 Posts: 106 | Is it a WAL MART battery? I've gone through four of them in the past three years. Same problem, bad cell. They give me a brand new one for free every time, but it is a pain in the [censored] to have to swap out the battery every year.
1940 Chevy 1/2 ton, 12 volt, 350/350th
| | | | | Joined: Oct 2009 Posts: 426 Shop Shark | | Shop Shark Joined: Oct 2009 Posts: 426 | Well, Im not quite ready to throw a grenade under the hood just yet, but it sure had me hot last night. Some new advice here, so Im going to try these posts first, then I'll let you guys know. | | | | | Joined: Oct 2009 Posts: 426 Shop Shark | | Shop Shark Joined: Oct 2009 Posts: 426 | No, the battery is the top of the line O'Reillys brand. | | | | | Joined: Oct 2002 Posts: 4,066 Bolter | | Bolter Joined: Oct 2002 Posts: 4,066 | do as Lincoln says, charge the battery up then disconnect the leads to the alt for one night and see if the battery stays charged, or go get the alt tested at a shop or store
I just had an alternator tested at O'reallys, it was bad, they also tested the replacement one to make sure it was good and it was.. the alternator was org on an 88 merc, they dont last for ever..the thing just went dead over night, thought it was the old battery that was 3 yrs old even though it was a 72 start from o'really.. it tested good after charged and this thing was as dead as you can get..
our battery with the old alt went from fully charged to about 9.7 volts in a few hours, once you are sure the alt is ok, then go to your next step...
a lot of folks dont think an alt can drain a batter by just setting and not running, they can......
Last edited by joker; 08/18/2011 11:15 PM.
Redryder pixMy HotrodA veteran - whether active duty, retired, national guard, or reserve - is someone who, at one point in his or her life, wrote a blank check made payable to The 'United States of America', for an amount of "up to and including my life."I am fighting cancer and I am winning the fight | Pain is part of life; misery is an option. | | | | | Joined: Oct 2009 Posts: 426 Shop Shark | | Shop Shark Joined: Oct 2009 Posts: 426 | I put the charger on the battery last night and fully charged based off of schumacher's recomendations. 10amps for 3 1/2 -7 hours, which did fully charge the battery. I didn't start the truck last night as it was 10:30pm once I was done. Went out this a.m. and the truck started fine. Ill get a voltmeter on it when I get home and unplug the alternator tonight to see what it does. The battery is a 750cca o'reilys and is probably 2 months old. The voltage regulator is about 1 month old and the alternator has about an hour of run time. New condensor and points....I also have a pertronix ignition, just haven't installed and I replaced the coil last year. All wiring has been replaced in the last two years and I've never had any blown fuses. Other than factory options, cig lighter, glove box light, radio...I dont have any non-factory accessories. Dont know if any of this helps. | | | | | Joined: Feb 2004 Posts: 29,777 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,777 | If the battery has cell covers, checking the acid with a a hydrometer is still a good idea. It's really the only way to know if the charge is complete. Battery acid has a specific gravity of about 1.265 which means the liquid weighs 1.265 times as much as water. Straight water always has a S.G. of 1.000. As the battery discharges, the gravity goes down as the acid is absorbed by the cell plates. Recharging drives the acid back out of the plates, and increases the weight of the liquid.
I start a recharge by checking and recording the S.G. of the acid in each cell, and recheck about once an hour during the charging cycle. When I get two consecutive readings without an increase, the battery is charged. Further charging just evaporates the water; it doesn't help the state of charge. Hydrometers aren't expensive- - - -a good one with a floating numbered vial and a temperature correction thermometer costs about $10.00 at most FLAPS. Stay away from the el-cheapo ones with a bunch of floating balls. To be absolutely accurate, the battery acid should be measured at a temperature of 80 degrees F., or a correction factor should be used. The thermometer shows how much to add or subtract from the base reading. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
| | | | | Joined: Oct 2009 Posts: 426 Shop Shark | | Shop Shark Joined: Oct 2009 Posts: 426 | Ok, ill check that out this weekend too. Im definitely getting a very good crash coarse in electronics, which is probably my weakest area in mechanics. I appreciate everyones help, and im confident ill get to the bottom of it with you guys.
| | | | | Joined: May 2005 Posts: 487 'Bolter | | 'Bolter Joined: May 2005 Posts: 487 | Here's something easy to check- Make sure the glove box light turns off when you shut the door.
That could drain a battery, probably not overnight, but maybe over a day or two.
Without the engine running, the ammeter should show a discharge with the headlights on. After engine start, headlights off, the ammeter should show a charge for 30-40 seconds. You should see the needle jerk when you turn on the headlights. Lack of these indications could indicate a bad ammeter or a blown ammeter fuse (63-72 GM trucks have fuses for the ammeter). A bad ammeter would not generally cause your issue. It would either have no effect or kill the entire electrical system like a master switch, depending on how its wired.
regards, Leon | | | | | Joined: Dec 2009 Posts: 164 Shop Shark | | Shop Shark Joined: Dec 2009 Posts: 164 | Make sure you check the alternator, your posting says that it only has an "hour run time" on it and the regulator is a "month old". Did they give you a replacement alternator with a built in regulator? You state you have an alternator and a regulator. Does the replacement look exactly like the old one? Or did they give you an "upgraded" alternator for someone doing a V8 conversation with a built in regulator therefore you have 2 regulators in the system fighting each other. Just something I noticed that stuck out at me.
Might be nothing, I just saw the first alternator that pops up at the Rock Auto website is the replacement with a built in regulator.
John | | | | | Joined: Oct 2009 Posts: 426 Shop Shark | | Shop Shark Joined: Oct 2009 Posts: 426 | Stock replacement alternator and external regulator.
| | | | | Joined: Dec 2009 Posts: 164 Shop Shark | | Shop Shark Joined: Dec 2009 Posts: 164 | Jon1963, so can you tell us what you found? It might help someone later searching for the same problem plus I am curious. | | |
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