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| | | | Joined: Aug 2010 Posts: 2 New Guy | | New Guy Joined: Aug 2010 Posts: 2 | Greets,
I have started restoring a 57 GMC that had the Pont. engine removed for an 69 olds engine and auto tranny.I understand these were pos. ground when stock?
The generator is still in place, so do I assume it is now a neg. ground? I haven't got it started yet, but cranked it by connecting each way, would that fry the volt reg. or anything?
So how do I know for sure which way to go? (gonna work on the points tomorrow). | | | | | Joined: Jul 2001 Posts: 3,887 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Jul 2001 Posts: 3,887 | 12V GMC's are neg ground '56 up, in 55 also if it was a V8 originally
Bill | | | | | Joined: Aug 2010 Posts: 2 New Guy | | New Guy Joined: Aug 2010 Posts: 2 | okay..thank you. Neg. ground it is.
(I don't remember where I read they were originaly pos. ground). | | | | | Joined: Jul 2001 Posts: 3,887 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Jul 2001 Posts: 3,887 | lotsa possibilities because GMC 6 volters were positive ground, all before 55 2nd series
Bill | | | | | Joined: Jul 2001 Posts: 3,887 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Jul 2001 Posts: 3,887 | interesting [I like they call the brow above the windshield a "smart cadet peak"], I'd think polarity would be mentioned, especially if it was mixed, but they do indicate V8's all were 12V, and I've always heard the positive ground ended with 6V in 55 I see as well at Keith's, the shop manual listed as 55-59 has a date of 1956 [so it's actually a 56-59 manual], and shows neg ground in schematics with no mention of 6V ... always did think GMCs were haywire  Bill | | | | | Joined: May 2010 Posts: 89 Wrench Fetcher | | Wrench Fetcher Joined: May 2010 Posts: 89 | Careful squeeze or youll start geting hate mail.
theres a tool for every job,and that tool is a hammer. it's easy to give advice if it's not your pocket book at stake. A well thought out plan,Is nothing. Untill exacuted twice.
| | | | | Joined: Jul 2001 Posts: 3,887 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Jul 2001 Posts: 3,887 | "start"?  Bill | | | | | Joined: May 2010 Posts: 89 Wrench Fetcher | | Wrench Fetcher Joined: May 2010 Posts: 89 | Not me. I'am a chevy man. Untell I work on my little brothers 53 GMC. LOL. Floyd. that is 6v pos. ground.
Last edited by 49 floyd; 08/15/2010 3:52 AM.
theres a tool for every job,and that tool is a hammer. it's easy to give advice if it's not your pocket book at stake. A well thought out plan,Is nothing. Untill exacuted twice.
| | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | If this thread started with a question about a Canadian truck, I believe all the Canadian 6 volt GMCs were Chev chassis and thus they were negative ground. I know my Canadian 51 GMC always was negative ground and according to GM, it has a Chev chassis. | | |
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