STUPID BATTERY QUESTION

TOM-WA-
TOM-WA- Senior Contributor
edited July 2012 in HUDSON
What can happen if the battery is installed backwards and Negative is connected to the Ground?

Will a car start if this if done and what possible consequences could result?


TOM

Comments

  • Geoff
    Geoff Senior Contributor
    Yes, the car will start and run, but the voltage regulator will hiccup for a while until the generator becomes re-polarised. Also the spark will be a little weaker, and it could be hard to start when hot. Put it back in correctly, and re-polarise the generator by temporarily shorting the B and A terminal on the regulator.
  • Geoff
    Geoff Senior Contributor
    Yikes, how come my post went in thrice???
  • hudsontech
    hudsontech Senior Contributor
    Old age jitters making you shaky Geoff??? LOL
  • Richie
    Richie Senior Contributor
    Tom, you need to completely kill the battery, dead as a doornail, then you can charge it in the correct polarity. Polarize as suggested by Geoff.
  • Uncle Josh
    Uncle Josh Senior Contributor
    Be aware that there are male and female batteries. You can tell a female because both terminals are negative.
  • Park_W
    Park_W Senior Contributor
    Richie, did you maybe read the original question incorrectly? The battery wasn't re-polarized, just connected backward.
  • RonS
    RonS Senior Contributor
    edited July 2012
    I know Tom just inquired will it start, but what about the heater fan, radio and (if any) electric fuel pump, or any motor for that matter? And won't the voltage regulator points fail quicker as the " spark" will jump across opposite as intended?
  • Richie
    Richie Senior Contributor
    Park, I did, I assumed that they had run it at some point. If it was not started at all just switching it around would probably be OK. I bought a car in that same situation and noticed right away the ampmeter worked backwards. The PO said it had been that way for a year. I killed the battery, reinstalled it and polarized the gen. and it has worked fine for the last year and a half. Thanks for pointing that out. Richie.
  • Park_W
    Park_W Senior Contributor
    edited July 2012
    Where it gets kind if dicey is on the old-timers that only have the "cutout" relay for the generator. Unlike the later VR's, it doesn't care which way the current is going, so as soon as there's about 7 volts to close the relay, it's now basically a 12 or 13v dead short with the battery. The wire from the cutout relay can get very hot.

    RonS, Geoff is correct in his comments above. There's really nothing that's polarity sensitive except the ignition coil, and the only that happens there is you lose about 15% of the spark voltage. Steve Engel, our radio guru, says some of the radios back in the thirties are polarity sensitive. But you can tell right away if the polarity's wrong ... everyone talks backward.
  • SuperDave
    SuperDave Senior Contributor
    he he he he
  • TOM-WA-
    TOM-WA- Senior Contributor
    OK I REINSTALLED THE BATTERY WITH POSITIVE GROUND, BUT I RE POLARIZED THE GENERATOR BY JUMPING THE REGULATOR FROM B TO A.

    I DID THIS WITH THE CAR NOT RUNNIING AND I AM STILL HAVING PROBLEMS WITH
    VERY SLOW CRANKING FROM THE STARTER WHEN THE CAR IS HOT...

    DO I NEED TO RE POLARIZE WHEN THE CAR IS RUNNING AND IS IT POSSIBLE THAT I DAMAGED THE STARTER WHEN I HAD THE GROUND REVERSED?


    THANKS,


    TOM
  • Geoff
    Geoff Senior Contributor
    No, you could not possibly do any damage to the starter, and no you don't need to do any more to re-polarise. check that your cables are heavy enough, and do a voltage-drop test whilst the starter is cranking. It could be your battery needs charging, or is suspect.
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