Something's draining my battery

Discussion in 'Small Block Tech' started by Seven6Regal, Jun 21, 2021.

  1. Seven6Regal

    Seven6Regal Well-Known Member

    I noticed about a month ago that my battery was dead so I went through the usual stuff to resolve the problem:
    1. Test and replace old battery - check
    2. Test and replace 8 yo alternator - check
    3. Replace faulty solenoid on starter - check
    4. Test amp and remote wire to ensure key off / power off - check
    5. Jumped and car then drove for most of the day - check
    6. Attempted to start car after 2 days of sitting - battery dead again!!!

    What could possibly be going wrong in the 1976 Buick Regal 350 engine?
     
    Pav8427 likes this.
  2. Mart

    Mart Gold level member

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  3. TrunkMonkey

    TrunkMonkey Well-Known Member

    With everything off, put a meter between battery cable and post, start pulling fuses one at a time and then put each one back in until you see the draw zero. That will be the circuit, then figure what all is on that fuse and eliminate each one.

    Make sure you either pull the wire off the door (light) switch or keep it presses, so you don't have a false draw from the door being open.

    Clock points burnt closed, trunk light, glove box light, can cause a continual draw.
     
  4. sean Buick 76

    sean Buick 76 Buick Nut

    Most of us just remove the negative terminal when parking it for over 24 hours.
     
    Waterboy likes this.
  5. Seven6Regal

    Seven6Regal Well-Known Member

    For the past 8 years, I didn't this problem after storing over the winter. This year it's been incessant.
     
  6. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!

    I don't think this is accurate.

    The car should be able to sit for quite a long time with out draining the battery.

    Measuring the amperage draw with the meter is the best way, as previously mentioned. The first thing to unplug would be anything aftermarket- radio, lights, etc. If your clock is dead it can still pull the battery down if it's plugged in.
     
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  7. sean Buick 76

    sean Buick 76 Buick Nut

    Yes you likely have a short. One of the guys above explained how to test the fuse block to determine the draw from the fuse block.
     
    Last edited: Jun 21, 2021
  8. Seven6Regal

    Seven6Regal Well-Known Member

    I wasn't planning on removing my battery cable over night. :)
     
  9. GSX 554

    GSX 554 Gold Level Contributor

    It is NOT a SHORT . A short is when power goes directly to ground .
    A drain is when some electrical item stays energized thus making the battery go dead after a while .

    And for the 3rd explanation An OPEN is when the power flow is interrupted somewhere in a circuit .
     
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  10. GSX 554

    GSX 554 Gold Level Contributor

    And you shouldn't have to . You have to find the circuit that is DRAINING the battery .
     
  11. 436'd Skylark

    436'd Skylark Sweet Fancy Moses!!!!!

    Pretty much. Although a small short that doesn't draw enough to pop the fuse will also drain the battery. Eventually it'll burn the car down or pop the fuse.
     
  12. gstewart

    gstewart Well-Known Member

    Under normal conditions (in our old cars), the battery will lose about 10% of its cranking power each month that it sits unused. Cold weather will increase the drain.
    I owned a 1981 Cutlass Supreme Brougham that suffered a battery dead condition. Turned out after using a meter & r/r the fuses, that the power antenna was cycling try to raise up from rest.
     
    Last edited: Jun 21, 2021
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  13. Seven6Regal

    Seven6Regal Well-Known Member

    I'm going to use a meter then pull the fuses. The battery is new as of May 2021 and the alternator as June 2021.
     
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  14. philbquick

    philbquick Founders Club Member

    Do you have a rear window defroster?
     
  15. Seven6Regal

    Seven6Regal Well-Known Member

    No. I'm thinking it's the radio drawing power from the cigarette lighter or the key not being completely off.
     
  16. 73 Stage-1

    73 Stage-1 Dave

    Or, it could be a bad door jamb light switch itself. The one on my driver's side has been wonky (sometimes the interior lights come on, sometimes the switch needs a wiggle. Well, just last night I was putting the car away I and noticed the recently installed LED dome light bulb slightly glowing. A wiggle of the jamb switch took care of it - and I moved replacing the switch up the "to-do" list. I already have a new replacement. My guess is a normal bulb wouldn't look on, but could still cause a draw.
     
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  17. Seven6Regal

    Seven6Regal Well-Known Member

    Thanks for all the replies. I will be on it sometime tomorrow.
     
  18. Dr. Roger

    Dr. Roger Stock enthusiast

    I put an aftermarket radio in mine (one of those that look vintage). It drains the battery after about 3 weeks. It doesn't have a light or clock or anything, but still draws a constant current. Never had this problem that until after I installed the radio. If it sets for more than 3 weeks between starting, I have to put it on the charger.
     
  19. Seven6Regal

    Seven6Regal Well-Known Member

    I had the guy at AutoZone check both battery and alternator before I left with them...learned that lesson years ago.
     
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  20. Max Damage

    Max Damage I'm working on it!

    The Autoparts store tests are practically worthless in my opinion. Unless they have radically improved their test equipment, it doesn't simulate the real world.

    I had an alternator I bought from Shucks (later became O'rielly's) that lit the alternator lamp in an old Suburu at idle. I brought it back and they put it on their tester and spun it to show me it charged. I asked "how many RPM is that" they answered " huh?" I explained the the idle speed of the car was not generating adequate current. "Well, it works ok on our tester" was their only response.

    I took it home and drove a 10 penny nail through the vents into the windings. Then I brought it back and got a new one.
     
    Last edited: Jun 27, 2021
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