Thread: Battery drain again or what?

Results 1 to 10 of 10
  1. #1 Angry Battery drain again or what? 
    BMWLOCO's Avatar
    BMWLOCO
    BMWLOCO is offline Ahhh, Malbec
    Join Date
    7, 3, 2003
    Location
    U.S.
    Posts
    161
    Angry Battery drain again or what? – 10-30-2003,01:38 AM
    Fellow Enthusiasts:

    A few months ago (July - August) I posted about having
    battery drain / charging problems... After several
    e-mail responses and troubleshooting we found that I
    had a battery drain form the trunk light. I adjusted
    the switch and charged the battery and Voila! all
    solved. THANKS all...

    This weekend (Sunday), I crank the car up for my drive
    to our club's track day and as I'm starting it I sense
    a slight delay while it's cranking. I don't pay it too
    much mind but make a mental note of it. Drive for
    about 1 hour.. Get to the event and stage my car on
    the grid. (This is after a few on and off's) Once it's
    MY turn, I proceed to start my car and "click and all
    light's on but no turn over". My OBC resets but my
    radio doesn't.. WTF!.. I call the track guru and he
    assists on giving me a push start.. All good.. I check
    the trunk light and all still good.

    For the rest of the day I'm afraid to turn the car
    off. I manage to do it a few times and it turns over
    fine. So I'm not worried. Track event done, I go home,
    park the car..

    Monday AM: A slight delay and I warm the car up.. All
    good.. Drive about 50 miles and all good... Tuesday
    AM: Slight delay in starting but O.K.. Go to work,
    park the car in the AM. I went on an official trip
    with a Gov't vehicle for the day and arrived this
    afternoon. So the car sat for a whole day and a half.
    TODAY at 4:30, Get to the car. Tries to crank, nothing
    but my OBC resetting, radio doesn't. I get it push
    started by a few buds and I'm off to home.. Drive home
    all good. (3 miles). Get home, Shut the car off and,
    Nothing but a little intent to crank and my OBC
    resets..

    What is going on?.. I'm thinking my Alt's voltage
    regulator ot a battery again.. HELP (AGAIN)..

    Richie
    91 M3
    Richie
    In an Embassy Somewhere..

    91 M3 - SOLD but not forgotten (to J.R. Nagy)
    03 Land Cruiser with the works
    06 Royal Enfield 350
    Reply With Quote  
  2. #2  
    Mmark's Avatar
    Mmark
    Mmark is offline Skidmark
    Join Date
    2, 8, 2003
    Location
    US
    Posts
    4,026
    10-30-2003,08:20 AM
    The battery is not being charged. Look for:
    bad voltage regulator.
    bad diodes.
    bad trigger circuit for alt.
    worn brushes in alt.
    dead cell in batt.
    poor batt gnd.
    Reply With Quote  
  3. #3 Thanks.. 
    BMWLOCO's Avatar
    BMWLOCO
    BMWLOCO is offline Ahhh, Malbec
    Join Date
    7, 3, 2003
    Location
    U.S.
    Posts
    161
    Default Thanks.. – 10-30-2003,10:00 AM
    I'll go ahead and remove my ALT today and get it tested...

    I'll keep you all updated...

    Richie
    Richie
    In an Embassy Somewhere..

    91 M3 - SOLD but not forgotten (to J.R. Nagy)
    03 Land Cruiser with the works
    06 Royal Enfield 350
    Reply With Quote  
  4. #4 Re: Thanks.. 
    EVOIIIM3's Avatar
    EVOIIIM3
    EVOIIIM3 is offline Super Moderator
    Join Date
    20, 12, 2002
    Location
    US
    Posts
    1,929
    Default Re: Thanks.. – 10-30-2003,11:48 AM
    Originally posted by BMWLOCO
    I'll go ahead and remove my ALT today and get it tested...

    I'll keep you all updated...

    Richie
    All you need to do is put a voltage meter on the batt with the car running, if it's under 13v it's not getting charged.

    Check....
    Ground strap on alt and motor
    voltage reg, on back of the alt
    make sure you belt is not slipping, or to tight
    make sure all the connections on the back of the alt are good.

    You can also test the regualtor by revving up and car with a volt meter on the red wire out of the alt.

    Do not click
    At least it's German:nah:
    Reply With Quote  
  5. #5  
    Stan
    Stan is offline ::s14 gadget guru::
    Join Date
    20, 12, 2002
    Location
    US
    Posts
    1,096
    10-30-2003,12:40 PM
    Same battery as before "charged the battery" - this could be part of the issue right there! And see below about other, modern batteries.

    Cuz car batteries are severely weakened by deep discharge. Do it once to a new battery and it winds up with only about 70% capacity. Do it once or twice more and that's all she wrote.

    Bosch alternators are set with a low output voltage. The OEM batteries do not require as much as some aftermarket units. Often an M3 measures at around 13 volts, maybe a few tenths more.You need to have really good grounds and a good starter motor. You can add an an adjustable VR to bosst the voltage a hair. I installed one and keep it set about 1/2 volt higher than stock. Lots of electrical folks say that Bosch alternators on old cars only charge the battery 50-70% in general. The stock alternator is a really good one and that basic type is used by those alternator based welding units some contractors use.

    If you look at the specs for modern dry cell batteries, they want higher voltage than our alternators are set for. So they won't fully charge on our cars. Modern BMWs are set for around 14 volts or more.

    Stan
    Reply With Quote  
  6. #6 O.K.. 
    BMWLOCO's Avatar
    BMWLOCO
    BMWLOCO is offline Ahhh, Malbec
    Join Date
    7, 3, 2003
    Location
    U.S.
    Posts
    161
    Default O.K.. – 10-30-2003,02:14 PM
    I'll test is as mike suggested...

    Updates to come...

    R...
    Richie
    In an Embassy Somewhere..

    91 M3 - SOLD but not forgotten (to J.R. Nagy)
    03 Land Cruiser with the works
    06 Royal Enfield 350
    Reply With Quote  
  7. #7 UPDATE.. 
    BMWLOCO's Avatar
    BMWLOCO
    BMWLOCO is offline Ahhh, Malbec
    Join Date
    7, 3, 2003
    Location
    U.S.
    Posts
    161
    Default UPDATE.. – 10-30-2003,08:07 PM
    Due to me screwing up my voltmeter, I removed my alternator, took it to Schucks and they tested it and said it was "good" It was putting around 13.00 +- ( I guess I should have gotten a REAL reading). Went back home and picked up the battery and they tested it. The battery is at 12.61 with 640 of CCA.

    I did notice that the ground cable was a little worn. I tried to locate on at Schucks but they didn't have any that matched.

    What's my next step?
    I'm gonna try to clean up all the contacts, ground, etc and re install the alt then get a reading again...

    Suggestions?..

    R...
    Richie
    In an Embassy Somewhere..

    91 M3 - SOLD but not forgotten (to J.R. Nagy)
    03 Land Cruiser with the works
    06 Royal Enfield 350
    Reply With Quote  
  8. #8  
    Stan
    Stan is offline ::s14 gadget guru::
    Join Date
    20, 12, 2002
    Location
    US
    Posts
    1,096
    10-31-2003,10:33 AM
    13 is too low, even if it meets "spec" IF you want to fully charge the battery to 100% and reliably keep it there. Run the lights, stereo, fans and the voltage drops...

    Stan
    Reply With Quote  
  9. #9 O.K.. 
    BMWLOCO's Avatar
    BMWLOCO
    BMWLOCO is offline Ahhh, Malbec
    Join Date
    7, 3, 2003
    Location
    U.S.
    Posts
    161
    Default O.K.. – 10-31-2003,11:46 PM
    Stan..

    So does this mean I need to replace my voltage regulator?.. I'm gonna go ahead and get it tested again as is and with a new regulator to see the difference..

    Meanwhile I removed my ground cable to get it inspected.. It looks good to me... I'm gonna sand/clean it and also clean all the contacts to the battery and posts tommorrow also...

    More to follow..

    I appreciate all your help so far..

    R...
    Richie
    In an Embassy Somewhere..

    91 M3 - SOLD but not forgotten (to J.R. Nagy)
    03 Land Cruiser with the works
    06 Royal Enfield 350
    Reply With Quote  
  10. #10  
    Stan
    Stan is offline ::s14 gadget guru::
    Join Date
    20, 12, 2002
    Location
    US
    Posts
    1,096
    11-03-2003,04:28 PM
    >>>Stan.. So does this mean I need to replace my voltage regulator?.. I'm gonna go ahead and get it tested again as is and with a new regulator to see the difference..Meanwhile I removed my ground cable to get it inspected.. It looks good to me... I'm gonna sand/clean it and also clean all the contacts to the battery and posts tommorrow also...More to follow..I appreciate all your help so far..R...<<<

    Regulators tend to work or not work..the voltage when working won't change much. Bosch alternators have easy to change VRs - you can do it with the alternator on-the-car. You can play around with a multimeter looking for voltage drops if you want to make sure there are no bad connections. Make sure the alternator ground is good. If you'd like, just install an adjustable VR for around 20-30 bux and you can set it as desired for whatever battery you use.

    Stan
    Reply With Quote  
« Previous Thread | Next Thread »
Posting Permissions
  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Forum Rules