Question1931 Chevrolet negative ground or positive ground/
Thank you,Ira
AnswerI'm somewhat embarassed to admit that I am not certain of my answer here, but I am fairly sure that all GM cars were negative ground, even though most other brands were positive ground prior to 1956.
If your car is still in original condition, you can determine this for yourself by doing one or more of the following:
Install the battery with the negative post grounded, then turn on the headlights and note which direction the ammeter moves. If it moves toward discharge, then you know you have it right. If it moves toward charge, then the battery is reversed and you need to install it with the positive post grounded.
OR: note the size of the opening in the battery end of the two battery cables. The larger opening is for the positive post. So if the smaller opening goes to the chassis, then you know the battery is to be installed negative ground.
OR: Note the 2 small wire connections to the ignition coil. If there is a "+" on one of the small terminals and a "-" on the other, the "-" terminal will go to the contact points in the distributor on a negative ground car, the opposite is true for a negative ground car.
If you wish a more trustworthy answer, I advise you to contact the Vintage Chevrolet Club of America at www.vcca.org/contact.htm and post your question to their technical help folks.
I'm sorry not to be more certain about this, but none of my reference books cover this car, and I never owned or worked on that early a Chevrolet.
Dick
