Clarification: Positive Ground?

On the 37' 120, I thought that was a positive ground car. Is that correct?

(my mechanic said he thought the battery was hooked up backwards)

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">On the 37' 120, I thought that was a positive ground car. Is that correct?

(my mechanic said he thought the battery was hooked up backwards) </div></div>

I am really going to go out on a limb here but I believe all Packards were positive ground

until 1955. they changed in 1956 to negative then.

I'm uncertain about the very early Packards thru about 1922, but thereafter all the 6 volt Packards thru 1954 are positive ground, as was true for many makes of cars in that era. The 12volt 1955 Packard cars remained at positive ground, and the 1956 12volt Packard cars became negative ground.

My 54 was Postive Gnd, but its very easy to switch it to Negitive Gnd, normally the positive lead has a larger post than the negitive post. you can check the ignition coil as to how it wired, and you can reset the generator to charge eather way...

Your 37 120 is positive ground.

Could someone have switched it to negative ground before you acquired it?

You can switch grounding without much trouble, at lesat on early cars.

My 1926 Eight had been switched to negative ground because the previous owners

fitted a fuel pump that was sensitive to the proper ground. I went back to vacuum tank

and put the system back to positive ground.

SOmetimes I've heard it said that you will need to "flash" the generator to give the field windings

the proper polarity to start charging correctly. Just once -- the first time. Momentarily close the

cut-out or touch the battery hot wire to the generator directly, bypassing the cutout. I did not do that

(out of curiosity) but had no trouble. Starters don't care about polarity, neither do lights or horn.

If you are using an electronic ignition or ignition booster, then be VERY careful about the proper ground.

(Ask me how I know :-) )

--Scott