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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Nov 2011 Posts: 8 New Guy | | New Guy Joined: Nov 2011 Posts: 8 | Just converted to 12v and the battery dies over night. Directions say to trash the voltage reg and connect all wires together minus field wire. Alternator is good. Had it tested. Battery is new. Also had that tested. Good to go. I left the negative side hooked up over night and it still killed the battery with pos unhooked. Any suggestions? | | | | | Joined: Feb 2004 Posts: 29,746 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,746 | If the battery dies with a cable disconnected, you've got a bad battery. Try another one. 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: Jan 2000 Posts: 124 Shop Shark | | Shop Shark Joined: Jan 2000 Posts: 124 | I would suspect the battery drain is coming from your alternator. It is common for a slight drain from the alternator to occur. That is why when modern alternator charging systems were introduced the accessory type ignition switch also came into being. The accessory post (now a fourth terminal on the ignition switch) was isolated from the rest of the terminals on the switch and that stopped the feedback current at that terminal. You can do the same thing with a DA Plug and you will not have to change out your ignition switch. Thanks Randy | | | | | Joined: Feb 2004 Posts: 29,746 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,746 | The parasitic drain from a built-in regulator is in the range of a few milliamps, and it would take a month or more to have a noticeable effect on the state of charge of a good battery. I cannot imagine how even that drain would have any influence on this situation, since the battery apparently died overnight with one cable disconnected ! A leaky diode bridge will discharge a battery quickly, but that should be apparent when the charge lead is connected to the alternator by the wire terminal making a spark as it's connected.
It sounds like there's either been some sort of mis-wiring done when the regulator was eliminated, and/or the battery has gone toes-up. 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: Jan 2000 Posts: 124 Shop Shark | | Shop Shark Joined: Jan 2000 Posts: 124 | Should be easy enough to check the wiring and see if it is correct. I have seen bad internal regulators and or diodes kill a battery overnight, but it is not common and it is usually in combination with something else that is wrong. Checking the wiring between the battery and the alternator is where I would start. Randy | | | | | Joined: Mar 2005 Posts: 1,636 'Bolter | | 'Bolter Joined: Mar 2005 Posts: 1,636 | If the positive post is disconnected from the battery, to my way of thinking it wouldn't matter if the headlights were left on. Nothing would drain the battery if it is disconnected.
I had a two month old battery die in my old truck a few days ago. Had a cell go wide open. | | | | | Joined: Feb 2004 Posts: 29,746 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,746 | A battery in my daily-driver Mercury Sable failed a few years ago during a 20-mile drive from my home to town. It went completely open-circuit to the point it would not burn the headlights, let alone crank the engine. The battery was less than one year old. 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: Mar 2005 Posts: 1,636 'Bolter | | 'Bolter Joined: Mar 2005 Posts: 1,636 | Us humans put things together, sometimes they just don't hold up. | | | | | Joined: Oct 2006 Posts: 9,671 'Bolter | | 'Bolter Joined: Oct 2006 Posts: 9,671 | Am I missing something here??? The guy said his battery was disconected and it went dead over night. In other words the battery might as well be sitting on his work bench and it went dead over night. Internally shorted battery????
DG
Last edited by Denny Graham; 12/02/2011 3:18 PM.
Denny G Sandwich, IL
| | | | | Joined: Nov 2011 Posts: 52 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2011 Posts: 52 | Change the battery, just because it load test fine when charged dont mean it is good.
52' Chevy 6400 2 ton
| | | | | Joined: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 | Something I noticed, you mention you had the positive cable disconnected and negative connected. That's the incorrect way to disconnect a 12 volt negative ground system. You should always disconnect the ground (negative) side first, and connect it last. connecting the positive side last can send a voltage spike through the system, damaging the alternator and any other electronics (radio, computer, etc) in the system.
Bill Burmeister | | | | | Joined: Jun 2008 Posts: 1,388 Shop Shark | | Shop Shark Joined: Jun 2008 Posts: 1,388 | Also, if you ground the wrench by accident when you do it Bill's (Longbo55), you don't blow your wrench up. | | |
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