Page 1 of 2 12 LastLast
Results 1 to 10 of 20

Thread: The old battery question with a twist on testing

  1. 07-23-2023, 12:28 PM #1
    Greg D.
    Greg D. is offline
    Late Apexing member
    Join Date
    Jan 2005
    Posts
    846

    The old battery question with a twist on testing

    For the first time - ever - my 72 refused to crank... Found both Sonnenschein averaging 11.8 but even after a charge the voltage appears to be dropping too fast. (12.8-> 12.5 in a couple hours) while connected together. Separately one is 12.7 the other is 11.9 quickly...

    I took them both out of the car to test them properly (and clean all the cables) and I see they are engraved with a date 11y old. Yikes. I recall being annoyed when I got them from Ft Lauderdale battery because they were already at least 3-4y old from memory but I guess 7y of service is fair !

    I cannot get a proper CCA rating on the Sonnenchein A512 40A - anyone knows what it should be ?
    They both tested as BAD on my solar tester despite OK voltage post charge (12.5 and 12.7 respectively) because I wasn't sure of what CCA to test against - one returned 206 CCA as AGMS (seems low) but 260 as Gel... So i guess I'm not even sure how to test those.. the, the bad one 6!!! Coincidentally I see sulfation coming from one of the plastic fill caps on that one.. So I guess I'm debating replacing one or both. One has for sure gone bad.

    So quick Qs, 1)can anyone tell me if I'm testing those right ? AGMS setting (they are AGM as far as I know), I lower CCA to min (300) but it returns differnt 3 for GEL or AGMS. I thought they were AGM batteries, which is gel, the nomenclature may go over my head.
    2) who has a the best deal or at least a decent deal on sonnenscheins, or in this day and age should I switch to something newer and better ? I like the stock setup but IMO the + terminal is too damn close to the top of the battery box for comfort and I see miata style batteries with side posts that appear a tad safer... Otherwise I hear Porsche has them now for $230 each, may do that..
    thx !
    Last edited by Greg D.; 07-23-2023 at 01:49 PM.
    Greg.
    ----------
    72 911T - 73 2002
    #1461
    Reply With Quote Reply With Quote
  2. 07-23-2023, 03:18 PM #2
    Longballa
    Longballa is offline
    Senior Member
    Join Date
    Jul 2006
    Location
    Corvallis, OR
    Posts
    2,586
    All the Sonnenchein's I've bought recently from Ft Lauderdale battery have had current born on dates. I'm staying with those. I've had good luck with them and they fit great.
    72S, 72 3.5L Signal Green, 914-6 GT Signal Green
    Reply With Quote Reply With Quote
  3. 07-23-2023, 10:01 PM #3
    edmayo
    edmayo is offline
    Senior Member
    Join Date
    Jul 2006
    Posts
    8,078
    You need to replace as a pair to keep the bad battery from drawing down the good one. If you use the correct O.E. rubber caps over the positive posts a short to ground can't happen. As to which battery that is your call, lead acid means a front pan will be in your future, and putting in off size batteries means cable and bracket modifications.
    Early S Registry member #90
    R Gruppe member #138
    Fort Worth Tx.
    Reply With Quote Reply With Quote
  4. 07-24-2023, 03:49 AM #4
    Boulder Bob
    Boulder Bob is offline
    Senior Member Boulder Bob's Avatar
    Join Date
    Dec 2003
    Posts
    210
    Quote Originally Posted by edmayo View Post
    You need to replace as a pair to keep the bad battery from drawing down the good one. If you use the correct O.E. rubber caps over the positive posts a short to ground can't happen. As to which battery that is your call, lead acid means a front pan will be in your future, and putting in off size batteries means cable and bracket modifications.
    So Ed, what batteries are you using now?
    73 911S Targa
    Reply With Quote Reply With Quote
  5. 07-24-2023, 03:59 AM #5
    edmayo
    edmayo is offline
    Senior Member
    Join Date
    Jul 2006
    Posts
    8,078
    Sonnenschein, I've been using them since the late eighties when I first discovered them, and I've got three dual battery cars.
    Early S Registry member #90
    R Gruppe member #138
    Fort Worth Tx.
    Reply With Quote Reply With Quote
  6. 07-24-2023, 08:08 AM #6
    Boulder Bob
    Boulder Bob is offline
    Senior Member Boulder Bob's Avatar
    Join Date
    Dec 2003
    Posts
    210
    Quote Originally Posted by edmayo View Post
    Sonnenschein, I've been using them since the late eighties when I first discovered them, and I've got three dual battery cars.
    Thank you Ed!
    73 911S Targa
    Reply With Quote Reply With Quote
  7. 07-24-2023, 01:00 PM #7
    Greg D.
    Greg D. is offline
    Late Apexing member
    Join Date
    Jan 2005
    Posts
    846
    Yup thanks Ed ! I have no bones to pick with Sonnencheins, I got good years out of them, but I was annoyed I got them "several years old- new" from the vendor. A friend has a whosale account at Porsche, will check their classic batteries locally as they supposedly have them now. If the price is close and a good fitment I'll get those here and now vs waiting.

    Still would have liked a CCA rating on the ol' sonnenscheins - guessing 300 ??? just for my education! But replacing both makes total sense.
    Greg.
    ----------
    72 911T - 73 2002
    #1461
    Reply With Quote Reply With Quote
  8. 07-24-2023, 01:30 PM #8
    RSTarga
    RSTarga is offline
    member #1515
    Join Date
    Mar 2009
    Location
    San Antonio, Texas
    Posts
    4,273
    As Ed says, Lead acid means the suspension pan might be damaged in case of a leak. After I had mine replaced I went through several variations of AGM setups but after Ed's Sonnenchein suggestion I installed some a couple of years back and they work great and look proper.
    David

    '73 S Targa #0830 2.7 MFI rebuilt to RS specs
    Reply With Quote Reply With Quote
  9. 07-25-2023, 05:54 AM #9
    G69
    G69 is offline
    Senior Member
    Join Date
    Jun 2010
    Location
    Garden State
    Posts
    312
    Perfect timing!

    I am ready to retire my Rube Goldberg battery setup and get OEM style batteries.

    Please post best vendor and I'll buy as well.

    Thanks!
    Reply With Quote Reply With Quote
  10. 07-25-2023, 06:25 AM #10
    RSTarga
    RSTarga is offline
    member #1515
    Join Date
    Mar 2009
    Location
    San Antonio, Texas
    Posts
    4,273
    2415 SW 3rd Avenue,
    Fort Lauderdale, FL 33315

    Phone: 954-525-5557
    Fax: 954-522-3748
    Email: susie@lauderdalebattery.com
    Web: lauderdalebattery.com
    David

    '73 S Targa #0830 2.7 MFI rebuilt to RS specs
    Reply With Quote 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


Message Board Disclaimer and Terms of Use
This is a public forum. Messages posted here can be viewed by the public. The Early 911S Registry is not responsible for messages posted in its online forums, and any message will express the views of the author and not the Early 911S Registry. Use of online forums shall constitute the agreement of the user not to post anything of religious or political content, false and defamatory, inaccurate, abusive, vulgar, hateful, harassing, obscene, profane, sexually oriented, threatening, invasive of a person's privacy, or otherwise to violate the law and the further agreement of the user to be solely responsible for and hold the Early 911S Registry harmless in the event of any claim based on their message. Any viewer who finds a message objectionable should contact us immediately by email. The Early 911S Registry has the ability to remove objectionable messages and we will make every effort to do so, within a reasonable time frame, if we determine that removal is necessary.