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oldblue1968chevy 11-22-2011 11:27 PM

alternator wire...
 
I have an alternator with a stud comming off the back and 1 16 guage wire that runs to the battery.

1-Is 16 guage wire heavy enough for this???

2-The battery has 2 prongs comming off it, I think one of the prongs has a wire going to the stub-I THINK, I'll check and try'n get pix.

Thans

VetteVet 11-22-2011 11:50 PM

Re: alternator wire...
 
Sounds like a one-wire alternator. 12 gauge is stock and 10 gauge is better. 8 gauge is better yet.

oldblue1968chevy 11-23-2011 11:25 AM

Re: alternator wire...
 
Ok,

Where should this wire be ran to? (currently to battery, gfs dad tells me that jerry rigged lol)

Rifter_Chevy 11-23-2011 01:57 PM

Re: alternator wire...
 
16 gauge? seriously? i honestly cannot believe it has not caught fire like that yet. I always go overkill on wiring so i would go 4 gauge but 8 would be fine.

VetteVet 11-23-2011 02:42 PM

Re: alternator wire...
 
2 Attachment(s)
Here is the stock diagram. I have bypassed the horn relay because the trucks from 67 up moved it under the dash in the cab. In reality as long as it connects to the positive battery terminal it will charge the battery. Wiring it like the diagram will give better power to the accessories.

Attachment 832582

Here it is in real time.

Attachment 832585

The wiring charts for AWG 12 show the amperage carrying limits for a given length of wire and for most applications it is enough. 10 gauge will give a smaller resistance and 8 less yet.

oldblue1968chevy 11-23-2011 06:22 PM

Re: alternator wire...
 
What do you recommend hooking it too (Battery,starter, other?)

VetteVet 11-24-2011 01:01 AM

Re: alternator wire...
 
Hook it to the joint and here's why.

http://www.madelectrical.com/electri...esensing.shtml

Not only that, but if you have an ammeter dash gauge then you will not be able to get the ammeter to work unless it is wired to the joint, so that there is a shunt between the battery and the alternator feed wire. I can get into this more but it can be a little technical. Can you provide more details on what system you have. Alternator type, internal or external regulator, type of dash gauge idiot light or ammeter and what wires you have. The 3 wire alternator SI conversions work better and provide more amperage output.

bsteele 11-24-2011 11:18 AM

Re: alternator wire...
 
I am not trying to hijack this thread, but seems like a good place to ask a question. I am in the process of doing the internal conversion. I cut the blue and brown wires at the clip and crimped them together(from the FAQ section). I know this is going to sound stupid, but do I plug the clip back in on the rad. support? I try to follow steps as I read them, but it never says to plug it back in.

VetteVet 11-24-2011 01:48 PM

Re: alternator wire...
 
1 Attachment(s)
Quote:

Originally Posted by bsteele (Post 5028274)
i am not trying to hijack this thread, but seems like a good place to ask a question. I am in the process of doing the internal conversion. I cut the blue and brown wires at the clip and crimped them together(from the faq section). I know this is going to sound stupid, but do i plug the clip back in on the rad. Support? I try to follow steps as i read them, but it never says to plug it back in.

What FAQ were you using? The one by Toddtheodd is the correct way to do it.

This picture shows the procedure. The brown and blue wires are not clipped together. The brown and white wires are clipped together and the blue and red are clipped together. Then the white wire is connected to the no. 1 terminal on the alternator and the blue wire is connected to the alternator at terminal no.2. The white wire is shown as black on the picture.
Todd eliminates the blue wire connection by running a short jumper from the large stud on the back of the alternator to the no. 2 terminal. This will work but the picture way of doing it gives a more efficient voltage drop sensing to the alternator internal regulator. Then you can remove the external regulator on the radiator support and the clip will no longer be used.

Most of the auto parts stores sell the rectangular white plastic plug that plugs into the alternator so you can splice the wires together and connect them to the alternator.

Attachment 832926

VetteVet 11-24-2011 03:33 PM

Re: alternator wire...
 
1 Attachment(s)
Here's a picture of the conversion with the brown wire run all the way to the alternator and the blue wire replaced by the red jumper.

Attachment 832978

oldblue1968chevy 11-24-2011 07:59 PM

Re: alternator wire...
 
I'll have pix tomorow nite or friday of everything, thanks vette

oldblue1968chevy 11-25-2011 12:22 PM

Re: alternator wire...
 
3 Attachment(s)
The red wire is the 16guage that goes STRAIGHT to the (+)

oldblue1968chevy 11-27-2011 02:29 PM

Re: alternator wire...
 
TTT

So I need to run a 10 guage wire from the alternator to......???

Where should the power wire for the fusebox come from?

Thanks you

VetteVet 11-27-2011 03:34 PM

Re: alternator wire...
 
If you look at the picture I posted, The red wire junction is how the stock 67 truck is wired, it's mine. This is done so that there will be a shunt between the battery and the alternator for the ammeter gauge to read charge or discharge. The fuse block feed wire is also connected there and it runs to the firewall block and feeds the light switch, the horn relay, and the ignition switch as well as the fuse panel.

The alternator external regulator sensing wire is also connected to the junction. It's all in the diagram I posted in post 9. If you have a one-wire alternator then you can connect it to the junction and the ammeter should still work. If you have the idiot light then it will not work because it is no longer connected to the alternator field circuit and the diode trio inside the alternator, to indicate the alternator output or the battery state of charge. If your truck has been converted to the internal regulator alternator and it's a one wire, Then you can just connect the gauge wire you choose to use from
the stud on the back to the junction or to the battery plus or to the starter terminal.

The picture you posted shows the small jumper wire going to the no.2 terminal on the alternator so you do have the internal regulated alternator. The question is whether it's a one wire or three wire style and are you getting any output from the alternator. Check with a voltmeter between the large post on the alternator with the + lead and the battery ground with the - lead with the red wire connected to the battery. S/B 14.5 volts +or- a few tenths of a volt. If you get no reading then jump another wire from the alternator stud to the no.1 terminal very briefly, just touch the two and recheck for voltage. If you get a good reading then you will have to complete the conversion like the diagram in post 9.

koda360 11-30-2011 10:17 AM

Re: alternator wire...
 
If I'm wrong, correct me please, but looking at your pics, it looks like a 3 wire alt. The white plastic plug on the top, should have a white wire on it as well as the smaller red wire.

The smaller red wire goes to the large post, or through the AMP meter, then back to the large post.

The small white wire would go through the warning light, then to the key on position of the ignition switch.

The heavier (8 or 10 ga) red wire goes from the large post on alt, to battery positive, or the junction block, if you have one.

VetteVet 11-30-2011 11:32 AM

Re: alternator wire...
 
-------

Quote:

Originally Posted by koda360 (Post 5039184)
If I'm wrong, correct me please, but looking at your pics, it looks like a 3 wire alt. The white plastic plug on the top, should have a white wire on it as well as the smaller red wire. If only we knew

The smaller red wire goes to the large post, or through the AMP meter, then back to the large post. The smaller red wire goes to the large post or to the no.1 terminal on the Ext VR and it isn't red it is blue, and from there it goes from terminal 3 as a red wire to the 4-way junction . If it's an internal regulator then the wire can go to the large post or better yet to the 4 way junction for better voltage sensing. It is usually a red wire all the way. It has nothing to do with the amp meter.

The small white wire would go through the warning light, then to the key on position of the ignition switch. This is true unless it's an external regulator then the white wire goes to terminal 2 of the External VR and exits at terminal 4 as a brown wire and then goes to the firewall block where it splits on the inside and becomes a resistance wire and goes to the key switch. The idiot light wire runs from the fire wall block to the light and then to the fuse panel where it is activated by the key switch power from the accessory terminal. If it's an internal regulator alternator ( 3 wire) then the white wire would go right to the firewall block by splicing into the brown wire at the external VR or just running all the way to the fire wall block to the correct brown wire. Check the diagram in post 9.

The heavier (8 or 10 ga) red wire goes from the large post on alt, to battery positive, or the junction block, if you have one. If you have an ammeter and want it to work then the large red wire will have to go to the junction block. The other positions will work to charge the battery and run the accessories.


fixit-p 11-30-2011 01:13 PM

Re: alternator wire...
 
I would keep it as close to the diagram Vettevet posted in post 9, you can upgrade certain wires but I wouldn't change the charge wire running across the rad support. Something like this.

http://67-72chevytrucks.com/vboard/p...ictureid=14305

oldblue1968chevy 11-30-2011 06:02 PM

Re: alternator wire...
 
I just have an aftermarket guage, no ammeter guage or anything.


I just want whatever I need to 'make it work'. Some/alot of the engine wiring has been hacked up changed since PO and me as well too.

koda360 11-30-2011 08:31 PM

Re: alternator wire...
 
2 Attachment(s)
Guess the biggest question is if the alternator is internally regulated or not...? Without that info, it's hard to be much help. My engine is out of a 72 and I wired mine as I said. I don't have an amp meter, I was told it went in series with the smaller red wire. IDK. I assumed by the center bolt rocker covers, it was a later model engine. But you know what they say about "ASSUME"! My plug and wiring look like this...

oldblue1968chevy 11-30-2011 09:18 PM

Re: alternator wire...
 
Im pretty sure its internally regulated.

Those are just vortec heads on a older block


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