'48 Electrical System Polarity

Posted by Michal On 2011/3/6 0:10:33

Hello Everyone,

Thanks to a healthy dose of ADD, I'm jumping all around on my 2272. Tonight I dug into the R9 OD. My harness is a mess but all the parts are there. I can push & pull the lockout knob under the dash and get into & out of overdrive at a standstill but as I studied the schematics I'm grateful to have found on this site, I see clear as day that they show Positive Ground while my car is clearly Negative. I triple checked this: Neg on battery goes to the block, Pos on battery goes to the starter.

Aside from my OD, all works on my car as expected. What do you all think? Previous owner switched to Neg. Ground? I think the generator can be re-polarized easily enough and bulbs & horns don't care. How about the starter? Am I safe to assume this is currently a Neg Ground car?

More importantly, what's this mean for my OD control? I actually don't mind wiring up a switch or two under the dash for manual engagement if need be but maybe the OD control isn't polarity sensitive either. If anyone knows something about these circuits, I could use a little guidance.

Thanks as always,