03-16-2009, 07:32 PM | #1 |
Registered User
Join Date: Mar 2009
Location: mulvane, KS
Posts: 200
|
drain on battery
got a 70 c20 with a new battery that goes dead over night but last forever if you disconnect the cables. is there any common trouble spots that i should check first?
|
03-16-2009, 07:46 PM | #2 |
Registered User
Join Date: Dec 2008
Location: Austin, MN
Posts: 117
|
Re: drain on battery
Maybe the radio but don't know if it would be quite that quick. What I do is check the current draw on the batt and then pull fuses until the current drops. Then I know what circuit it's in.
|
03-16-2009, 10:18 PM | #3 |
Active Member
Join Date: Jul 2007
Location: Centrally located between Houston, Austin and Waco. BCS area.
Posts: 7,947
|
Re: drain on battery
Do a search on battery draining or something similar to get some more ideas, but I would start with checking the easy things first.
If you have a meter than checking the amps and removing fuses as norske mentioned is a good first start. Things that you can disconnect for test purposes are any aftermarket components, like radio, cd player, amp, etc. The alternator and/or voltage regulator can cause battery drain also. If you have the external regulator, disconnect it and the alternator. If it's the new style internally regulator, the diodes can cause voltage drain so disconnect it also. Check for bad cables and connections. |
03-16-2009, 10:38 PM | #4 |
Registered User
Join Date: Mar 2009
Location: mulvane, KS
Posts: 200
|
Re: drain on battery
tried pullin the fuses one by one and it never changed, but there is a defference of a tenth of a volt on my multimeter when i disconnect the battery cable. any other suggestions?
|
03-16-2009, 10:48 PM | #5 |
its all about the +6 inches
Join Date: Jan 2001
Location: Hilliard Ohio
Posts: 2,690
|
Re: drain on battery
have you done any electrical work to it lately? Anything not working? It takes a good load tokill a fresh battery overnight.... a light would have caught your eys, horn working?
|
03-16-2009, 10:58 PM | #6 |
Registered User
Join Date: Mar 2009
Location: mulvane, KS
Posts: 200
|
Re: drain on battery
the alternator seems good had no change. not sure how to tell if its internal or externaly regulated. not aftermarket bs on the truck and i just bought it and tryin to work the bugs out of it. horn works but tail lights, radio, and heater fan doesnt work right now but shouldnt there of been a change when i took those fuses out if it was one of em?
|
03-16-2009, 11:35 PM | #7 |
Registered User
Join Date: Nov 2006
Location: lafayette, ga.
Posts: 832
|
Re: drain on battery
what he said
__________________
Freedom is never more than one generation away from extinction. We didn't pass it to our children in the bloodstream. It must be fought for, protected, and handed on for them to do the same.... Ronald Reagan |
03-16-2009, 11:56 PM | #8 |
Registered User
Join Date: Jul 2007
Location: Toppenish, WA
Posts: 15,708
|
Re: drain on battery
It sounds like it might be a bad diode in the alternator.
That would cause an unexplained drain like that. Another thing that can cause a battery drain is a dirty top on the battery that allows current to flow across the top of the battery. Take your volt meter and hold one lead on the appropriate post of the battery and touch the other to various spots on the top of the battery. See if there is any reading. I have seen as much as eight volts flow across the top of a dirty battery. The cure is to clean it off. The 70 will have an external regulator unless the alternator has been changed. |
03-17-2009, 12:37 AM | #9 |
Still livin the "dream" in '54
Join Date: Nov 2006
Location: Tucson, AZ
Posts: 2,656
|
Re: drain on battery
Mine had a similar problem. Found out my ignition cylinder was bad allowing me to take my key out at any time in any position. I was turning it all the way to the left to shut my truck off, leaving the accessories on all night, allowing the battery to drain. I never thought anything of it, just thought something else was the kulprit. The key should only come out when the truck is all the way off.
Got a new cylinder and problem went away! Don
__________________
Current build. 1954 Chevrolet 3800 "Ella" SOLD! My '67 stepper "Tangerine Dream" "Anything worth doing is worth doing right" James Dean “When you have eliminated all which is impossible, then whatever remains, however improbable, must be the truth.” Sherlock Holmes "There is no spoon." Neo Last edited by Richard8971; 03-17-2009 at 12:39 AM. |
03-17-2009, 08:54 AM | #10 | |
Active Member
Join Date: Jul 2007
Location: Centrally located between Houston, Austin and Waco. BCS area.
Posts: 7,947
|
Re: drain on battery
Quote:
Try disconnecting cables mentioned. If you have time, disconnect all and reconnect one at a time until failure reoccurs. Then you know exactly what component failed. Check on the radiator support drivers side and look for a small box with cables going to it. That's external regulator. . Last edited by 68gmsee; 03-17-2009 at 08:55 AM. |
|
03-17-2009, 09:11 AM | #11 |
Driven a 72
Join Date: Nov 2008
Location: Minnesota
Posts: 166
|
Re: drain on battery
I have the same problem. My ignition does exactly as descibed above. I can take the key out at any position. What part would I need to fix this. The ignition switch?
__________________
1996 GMC JIMMY 1972 CHEVY C10 LWB My 72 c/10 Build: http://67-72chevytrucks.com/vboard/s...d.php?t=318729 |
03-17-2009, 09:39 AM | #12 |
Active Member
Join Date: Jul 2007
Location: Centrally located between Houston, Austin and Waco. BCS area.
Posts: 7,947
|
Re: drain on battery
If you know the keylock number sometimes a new key will help, but more than likely it's just worn out tumblers.
Here's some good info from our resident lock doctor to help you out: http://67-72chevytrucks.com/vboard/s...d.php?t=213860 |
03-17-2009, 10:33 AM | #13 |
Driven a 72
Join Date: Nov 2008
Location: Minnesota
Posts: 166
|
Re: drain on battery
Good stuff! Thanks.
__________________
1996 GMC JIMMY 1972 CHEVY C10 LWB My 72 c/10 Build: http://67-72chevytrucks.com/vboard/s...d.php?t=318729 |
03-17-2009, 11:26 AM | #14 |
I miss this truck.
Join Date: Dec 2001
Location: Lexington, KY U.S.A.
Posts: 2,863
|
Re: drain on battery
The other thing that always gets mentioned when you start seeing electrical bugs, check your grounds. pull the screw out of each end of all the ground straps, clean both surfaces, and reconnect.
Also, I learned the hard way that a worn V-belt will turn the alternator, but will actually OVER charge the battery, I can't explain it, except to say that I wound up paying a mechanic $70 to diagnose and replace the belt. Check the edges of the belt closely. Also, somebody mentioned the diodes of an internally regulated alternator earlier. Any of your local auto parts stores will bench test them, part of that test is checking the diode pattern.
__________________
'07 GMC Acadia SLT. Sweet ride. '08 Crew Cab Z-71 short bed. Really like this truck A LOT. |
Bookmarks |
|
|