1973 750GT stock regulator wiring?

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baddean
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1973 750GT stock regulator wiring?

Post by baddean »

Hi All,
I am in the process of rewiring my '73 GT to clean it up and replace 40 year old wires.
I've replaced the stock fuse block with a modern blade type and have figured out my ultimate lay out, except....
I am going to power everything through the fuse block and switch from the battery. On the stock regulator there is a orange wire that fed the old fuse block, I assume, to power some of the lighting system from the alternator based on the wiring diagram.
The question to the electrical gurus is, do I have to use that terminal (orange wire) on the regulator at all if I am using the battery for all of my power?
(On the wiring diagram it says brown on the regulator but the wire says orange)
If you look at the wiring diagram here on Bevel Heaven for the 750GT you'll see that there appears to be two sources of power to the dash light switch. One is the orange wire from the regulator and the other is the the red wire from the key switch.
I have upgraded my alternator so I have plenty of voltage to work with as far as charging the battery.
I just don't know what that fifth terminal on the regulator is for. (2 yellow wires- 2 red wires and that fifth wire?)

Hope this isn't too confusing ( the more I read it back to myself the harder it is to understand)
Thanks,
Dean
Faster, faster until the thrill of speed overcomes the fear of death.
Hunter S Thompson RIP
baddean
Parallel Twin
Posts: 148
Joined: Sun Jun 17, 2007 7:11 pm
Location: Cincinnati Ohio

Re: 1973 750GT stock regulator wiring?

Post by baddean »

Thanks for looking. I figured it out.
Dean
Faster, faster until the thrill of speed overcomes the fear of death.
Hunter S Thompson RIP
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BevHevSteve
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Re: 1973 750GT stock regulator wiring?

Post by BevHevSteve »

Please post the answer to your question so we will know., thanks
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Steve Allen (925)798-BEVL[2385] Ride'm, Don't Hide'm
Ducati/Euro Spares -> https://Store.BevelHeaven.com
baddean
Parallel Twin
Posts: 148
Joined: Sun Jun 17, 2007 7:11 pm
Location: Cincinnati Ohio

Re: 1973 750GT stock regulator wiring?

Post by baddean »

Ah, I guess that that would be useful.
In the schematic that is shown in the "Techical info" area of the main page under "wiring diagrams" for the 750GT you'll see that that the regulator shown has 5 terminals. 2 for yellow wires from the alternator, 2 for red wires (that are actully connected to one another inside of the case), one from the alternator and one that powers fuse #1 on the fuse block. The fifth terminal shows brown (marrone) on the diagram. This wire (brown) is actually inside of the regulator case. The orange wire runs from this terminal to power fuses 2,3,4 on the fuse block. This terminal is nothing more than another 12v power source that is activated when the ignition switch is turned on. In other words it is connected to the red wires inside of the regulator case but switched with the ignition switch hence two power sources. Simple, actually once I stopped overthinking things a pulled my head out of the dark place.

Below is a link to a diagram of the internal wiring of the voltage regulator.
(Steve, is there a way we could get this included in the "Wiring diagrams" section?)
http://willyg.homelinux.org/Alternator/750regulator.jpg
Regulator Schematic Copyright © 2002 Malcolm Moore
Some of the info on this was found on Willy Gonnason's web site.

Also from Willy's web site some very good regulator info.
http://willyg.homelinux.org/Alternator/regulator.html

Hope this is useful,
Dean
Faster, faster until the thrill of speed overcomes the fear of death.
Hunter S Thompson RIP
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BevHevSteve
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Re: 1973 750GT stock regulator wiring?

Post by BevHevSteve »

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Steve Allen (925)798-BEVL[2385] Ride'm, Don't Hide'm
Ducati/Euro Spares -> https://Store.BevelHeaven.com
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