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| | | | Joined: Nov 2011 Posts: 141 'Bolter | | 'Bolter Joined: Nov 2011 Posts: 141 | The 46 GMC 3/4 ton I just bought was in the process of converting to 12 volt. The alternator has one wire that is no connected. I know that some systems have single wire alternators, but am not sure if that is what I have. How do I tell if I need to connect the second wire, and what does it go to if I do? Thanks, Dan
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| | | | | Joined: Nov 2009 Posts: 239 'Bolter | | 'Bolter Joined: Nov 2009 Posts: 239 |
Is there a jumper wire from the big bolt (the battery connection) on the back of the alternator to one of the smaller bolts (the #2 connection) on the back of the alternator?
If so, the wire is not really needed. The second wire is "sense" lead, which is used by the internal regulator to determine the output voltage.
Also, I'm not sure what the other end of your wire is connected to, but in a regular situation, it is connected to one leg of the ignition switch. You could use an ohm meter or bug light to find the the other end.
Last edited by di1953gmc; 11/15/2011 6:59 PM.
When I die, I want to go peacefully like my Grandfather did, in his sleep -- not screaming, like the passengers in his car.
-Unknown-
| | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 |
You will most likely be switching from 6v positive ground to 12v negative ground. Make sure you ground the battery appropriately.
Also, will you be changing the starter?
| | | | | Joined: Nov 2011 Posts: 141 'Bolter | | 'Bolter Joined: Nov 2011 Posts: 141 | The starter was changed. And it has the 12 volt neg ground.
There is a small red jumper wire that goes from the big red wire/bolt on alt to the plastic connector with the second yellow wire next to it. The yellow wire is no connected now. The lights are not powered yet also. As is the gas gage.
I was wondering if the yellow wire from the alt goes to the panel somewhere? He had run it through the fire wall but not connected it. There was a plan the install turn signals, but I'm going to wait and do that as a separate project.
Trombones Totem Poles And Old Trucks!
| | | | | Joined: Nov 2009 Posts: 239 'Bolter | | 'Bolter Joined: Nov 2009 Posts: 239 | The yellow wire is for the dash "idiot" light, which is not a standard option on a 46. Perhaps the PO wanted to put an indicator light on the dash, but didn't get around to it.
Last edited by di1953gmc; 11/15/2011 7:16 PM.
When I die, I want to go peacefully like my Grandfather did, in his sleep -- not screaming, like the passengers in his car.
-Unknown-
| | | | | Joined: Nov 2011 Posts: 141 'Bolter | | 'Bolter Joined: Nov 2011 Posts: 141 | Thanks! Wire now gone .
On to the next question------------------->?<--------------------
Trombones Totem Poles And Old Trucks!
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