HELP Wiring horror... Am I going nuts?

[FluoFerret]

I had the genious idea to repair the wiring harness of my car and bring it back to OEM since it was crappy made by the workshop when they swapped the engine in...

I bought a Powermaster 150amp alternator (67293 ) with internal voltage regulator, and I wish to get the best possible wiring while restoring the OEM cable-situation. The big heavy wire will be going from the alternator to the battery-positive, that's obvious, even to me.

What's baking my brain is the question on how to correctly connect the 2 cables going to the fusebox? I understand that 1 is for keyed contact while the other is permanent current. Is the ignition-keyed wire the one receiving the current from the internal alt-voltage regulator? There was 1 connector provided with the alternator.


The next two pictures shows some of the horror made by that loonatic who swapped the V8 in instead of the V6...


On my wifes 1972 firebrid, I can't see where the cables are supposed to go, only guess, since the original wire harness wrap is still in place. Also, why is there a 30amp fuse? Is it to protect the other wire with permanent current?


I am totally out of ideas -.- please help!

 

[Bonnewagon]

You can start here. Most of these cars are similar. My 1972 Pontiac Catalina used the 30 amp fuse too. I think it was for the AC/heater/blower system. https://maliburacing.com/a-g-body-wiring-diagrams/

 

[fleming442]

Just connect the excite wire to the brown in the factory harness and install a diode if it suits your fancy. Or, connect it to any ignition on (pink circuit). The brown will keep the alternator light off.

 

[Drkuhar]

On The 2 wires that come out of the pigtail the small gauge wire goes to the brown factory harness wire for the charge light on the dash. I've always looped the larger red wire back to the stud on the back. In the original harness the large red wire went to a splice by the starter. Either way it gets battery voltage

 

[fleming442]

Exactly, voltage sense for the regulator- the aftermarket 2 pin plugs are usually both 16ga though.

 

[mikester]

Check out this thread. I started it because I was going through the same stuff. You might find the answer you need.

Starter/Alternator Wire Question Update

I deleted the thread about fusible links just now. Moving on to fixing the whole harness. I looked at all the options regarding a new fusible link. Turns out the local auto parts houses didnt carry anything other than the ones made by Dorman. The way theyre made would make it a pain in the butt...

gbodyforum.com

 

[CopperNick]

Hmm. With my Monte, when I encountered the rats nest of wires that ran from the alt down to the starter solenoid I also found that some of them had burned out and had just been disconnected and left to hand. What I did was to insert a circuit breaker and relay into the harness to rebuild it. As you commented, the red wire feeds the battery. From there, another red wire goes to the "batt" post on the breaker and from there to the relay. From the relay a final red wire goes down to the solenoid. To make/break the starter circuit the two existing wires that fed power into and out of the key switch get repurposed. The "brown?- pink?- purple?" wire that fed power to the key keeps on doing so. The power out wire, whatever color it is, gets rerouted slightly so that it now feeds power intto the actuation or initiation side of the relay and the out wire for that side simply goes to ground. Using the breaker and relay both eliminates the need for fuses in that circuit and delivers 12V directly to the starter without having it routed through the key switch on the way. Engine turns over far more readily and quickly

 

[CopperNick]

Clarification. Sorry, site crashed out before I could edit my original post. Okay. Power into the breaker comes from the battery and is attached to the "batt" terminal of the breaker. From the breaker, there are two wires that are attached to the "Aux' terminal. One goes directly to the relay and the other is the wire that feeds power to the ignition switch. The relay is an electro-magnetic switch of sorts. Internally it has two circuits, one heavy and the other light. Power fed to the "light" circuit closes a connection and makes the heavy circuit, allowing power to flow through it to be fed to the starter motor. The "light" circuit gets its power from the key switch. Turning the key on closes the "light" circuit in the relay which in turn actuates the heavy circuit which feeds power to the starter.(Takes longer to explain than to happen,) When the key is released, the circuit is broken and starter quits turning.

If considering this modification, two things to factor in. First is that the power to the breaker can come from the stud on the alternator as it is wired to the battery. Second is to either stick with the wire gauges that are being used by the factory to begin with or go up one gauge heavier. The heavier gauge wire both tolerates heat better and offers less resistance over the length of the circuit or harness being created. If you think it would be useful, could be able to take and upload a pic or two of how it currently looks.

Nick