Battery installed backwards

snowshoe90aolcomsnowshoe90aolcom Posts: 121Expert Adviser
Kind of off topic but I bought a 1950 Nash from a guy who installed the battery in backwards....neg. ground instead of pos. ground. I drove it around about 200 miles not thinking anything about it until I received a service manual and discovered the mistake. The car started very well and ran perfect but yesterday the Gen. light came on and stayed on. Did anything get messed up? I know when I took the generator out of my '50 Commodore for service I polarized it before starting the car and it works fine. Is that all I need to do to this Nash or should I be looking for other problems to come up. The Nash only has 38K on it and the wiring has never been messed with.   Terry


  • cchancelcchancel Posts: 187Member
    Someone had done this to my 1951 before I bought it.  I swapped the cables and it still started right up.  The points in the voltage regulator needing cleaning because they were unusually worn (Later I replaced the voltage regulator).  I have heard that the wrong polarity will significantly reduce voltage regulator life expectancy due to wear on the points. I re-polarized the generator as well.

    The voltage regulator is where I would start.

  • GeoffGeoff Posts: 4,355Senior Contributor
    The voltage regulator is the problem.  Check that it is marked "Pos. ground".   Most Auto-lite regulators have dis-similar metal in the points of the voltage coil, causing them to burn if connected the wrong way round.   
    If you're stuck in a hole, stop digging.
  • snowshoe90aolcomsnowshoe90aolcom Posts: 121Expert Adviser
    You guys are right. I took the VR off and it's marked 6v P. I'm hunting for a new one.
  • GeoffGeoff Posts: 4,355Senior Contributor
    You should just be able to clean the voltage coil points and it will burst back into life.  You will notice one side is yellow and the other silver.  The yellow side is softer.   Just use a bit of folded 400 grit sandpaper, and wash it out with acetone afterwards.
    If you're stuck in a hole, stop digging.
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