VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1929-1932 positive ground battery

I have looked thru the owners manual, maint. manual , parts book and I have not found where it says they used a positive ground.

Where 1930 thru 1932 positive ground ??

In what year did they go to neg. ground ??

On a positive gnd. system does the + terminal on the coil go to the dist ??

Thank you, Larry.

All the years you are talking about use NEGATIVE GROUND.

I recently purchased a 1930 and it is wired as a positive ground.

The pos. terminal of the battery is wired to ground.

They positive terminal of the coil is wired to the dist.

It runs fine as is. Does it make sense that the starter and

generator would work OK ??

The starter works fine but I'm not sure about the generator.

Any thoughts ??

Thank you, Larry.

All Chevrolets use a negative ground system, not a positive ground system.

Once they are polarized, generators don't care if they are negative ground or positive ground.

What about the starter motor, would it operate with a positive ground?

It should. However, to avoid future issues, you are much better off going back to the negative ground system like your car had when it was new.

My '37 MG is positive ground. Seems like that was common in England in the '30s. Several years ago, my son was helping me install new batteries (two 6V pos gnd for a 12V system). He went with negative ground. It was over a year before I noticed the mistake and corrected it. The car didn't seem to care at all. I would think that in Australia you would experience a combination of British and Yank thinking. Make it negative ground and hope for the best. If the coil wiring is still an issue, I'll have to look at my book tomorrow.

The car with the positive earth isn't mine I was just curious if the starter would operate properly and not run backwards.

My MG didn't care and the starter and generator continued to work correctly with the battery both negatively and positively grounded.

I don know about a Chevrolet starter running backwards but I do know about a Poulan Pro Lawn mower with a 17.5 HP Briggs. I swapped out the battery and didn't notice that the replacement had terminals opposite of the old one. when I hit the starter it would hum right along but the bendix wouldn't catch. Scratched my head and said my sunday school lesson backwards, then noticed my mistake. Swapped the battery back around and everything worked for a few times, then the solenoid went bad.

This may be the wrong site for this info, but are not the Fords of this era all pos ground? So some one may have assumed, and made the leap from one brand to another.

Yes Ford had many models back in the 40s and early 50s with a positive grounded electrical system as did GMC.

Pertronix makes their 6 volt ignition moduals with positive for Fords and 6 volt negative ground modules for Chevrolets and other GM cars, so there is one application that you need to observe positive vs. negative ground systems when you install a Pertronix 6 volt ignition module.

I could notfind a Petronix for my 31. Do they exist?

Curiosity got the better of me tonight and I dug out a spare 1930 model starter and hooked it up to a battery with jumper leads and to my surprise it ran the same way with either positive or negative earth.

series dc motors will turn the same way neg. or pos.

to change direction of rotation change the field or armature.

just like the forward / reverse switch on your hand drill.

a friend with a model A off brand car and a chevy put a new battery in his fxxx, grounding it negative as in chevies. he took a while to figure out why the thing started hard, heated up, had low power. when he turned the battery around, it cured all the sudden problems. he said it also effected the direction the spark traveled in the plug which made some difference.