Author Topic: Battery polarity question  (Read 5349 times)

mespe

  • Guest
Battery polarity question
« on: February 07, 2009, 00:12:20 »
Hi all,

I bought a 1967 250SL, that had been in storage for years. The battery in the car was disconnected, but the red wire going to the battery (by the + terminal) is grounded on the chassis, and the black wire goes off toward the engine and starter. It looks like this car (a Euro version) has a positive ground. I did a search and found a thread that says all pagodas are negative ground. So now I'm completely confused,,,

jeffc280sl

  • Guest
Re: Battery polarity question
« Reply #1 on: February 07, 2009, 02:10:17 »
Everything I have read say the SLs are negative ground.  I have owned 2 of them and they were both negative ground.

glenn

  • Guest
Re: Battery polarity question
« Reply #2 on: February 07, 2009, 03:51:52 »
'in storage for years'

graphic66

  • Guest
Re: Battery polarity question
« Reply #3 on: February 07, 2009, 05:32:34 »
It will most likely have a fried voltage regulator with the polarity reversed. It will still start and run like that. Switch it back and see if it's charging.

bpossel

  • Guest
Re: Battery polarity question
« Reply #4 on: February 07, 2009, 12:12:09 »
Mespe,

Reading your description below makes me think that the ground cable (-), connected to the body, is just "red" in color".  Color makes no difference, but typically negative is "black".

I would also guess that the battery in your car has the positive (+) terminal on the left side and negative (-) on the right side which makes the ground cable stretch & connect to the battery in a diagonal fashion. 

In summary, just make sure the cable connected to the chassis is connected to the negative (-) terminal on the battery.  The positive (+), longer cable, connects to the starter.

To make it easier in the future, next time you buy a battery, get one with the terminals reversed (neg=left; pos=right).

Bob  :)
« Last Edit: February 07, 2009, 13:25:52 by bpossel »

mespe

  • Guest
Re: Battery polarity question
« Reply #5 on: February 07, 2009, 13:09:57 »
OK Cool Consensus is Neg ground, that's where I'll start. thanks for all the input. Can't wait to get started on her,,,