Quote from: coffeecreek on April 19, 2014, 02:18:19 AM
The correct answer is , you will have to do some investigating . It is possible to purchase a positive ground alternator . It is also possible to purchase a 6 volt alternator in either positive , or negative ground . ( I have a positive ground 6 volt alternator on a Model A Ford right now ) . Hopefully it will be marked on the alternator .
THIS IS the correct answer. A good example was the older Delco / Mopar (don't know about Ferds) back when they had individual diodes instead of a bridge. It was an easy afternoon job to remove all six diodes, swap their positions, and you have a POS ground alternator
There DOES exist some heavy trucks that were POS ground 12V. What a PITA to get 2-way radios working in them!!!!
You can easily figure this out. Get a charged battery, and do NOT hook up the "hot" lead. Ground say, the NEG (you have a 99% - 1% shot, LOL) and then take a test lamp and wire IN SERIES with the positive post to the hot stud on the alternator. Do this with the main charge wire to the alternator unhooked
If you do NOT get a light, you have the polarity reversed. If you DO get a light, the battery is backwards
To make this even more convoluted, sometimes "back in the day" either dry-charged "new" batteries or batteries which had been run completely dead somehow got "Reverse" charged. So you could NOT go by battery post markings. In my 66 years, I've run into this at least twice.






