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Stock 3G wire harness size

  • Thread starter Thread starter scrutmonkey
  • Start date Start date Jun 23, 2007

scrutmonkey

Member
Jan 17, 2003
243
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16
San Jose, CA
Jun 23, 2007
#1
  • Jun 23, 2007
  • #1
I'm doing a conversion of my alt to a 3G and I have a harness that was cut from it.

I've been reading that we need at least a 6 gauge or a 4 gauge wire. What size is the stock harness wire going to the starter noid on a 3G?

Here's the pics

View attachment 380120

View attachment 380121

thanks for the help in IDing the wire size.
 
6

67efivert

Member
Jan 26, 2003
348
0
16
lincolnton nc
Jun 23, 2007
#2
  • Jun 23, 2007
  • #2
looks like 6 gague to me and thats what i usally run when upgrading alternators
(mainly because i got a roll for free)
 

rbohm

Founding Member
Apr 12, 2002
6,698
550
204
tucson,az
Jun 23, 2007
#3
  • Jun 23, 2007
  • #3
i agree that looks like a 6 gauge wire to me also. that is the minimum i would use.
 

scrutmonkey

Member
Jan 17, 2003
243
0
16
San Jose, CA
Jun 23, 2007
#4
  • Jun 23, 2007
  • #4
awesome, thanks for the input guys...i guess it's off to the car audio store to grab some more 6 GA wire and a ncie fuse holder.
 

joesgt281

Founding Member
Oct 2, 2002
163
0
0
Katy, TX
Jun 25, 2007
#5
  • Jun 25, 2007
  • #5
Just got done with this part of the project.
I had the same question, same wiring, and went down to the local O'Reillys to see what they could do.
To confirm what's already been answered, yes the stock wire is a 6 gauge and it can be found at O'Reillys either at their stores or online. Here's a link to what I got:
http://www.oreillyauto.com/EW3/Prod...rchFor=PW6R&bid=1182641462484&cycleCount=1047

And, I did just what you were planning and that was to get a stereo system fuse holder to put inline. I wasn't crazy about just using the setscrew in the holder against a bare wire so I added lugs to the wire and machined down a bolt to take up the space below the lug so the setscrew and lug would have something flat to bear down against.




 

scrutmonkey

Member
Jan 17, 2003
243
0
16
San Jose, CA
Jun 25, 2007
#6
  • Jun 25, 2007
  • #6
wow, that looks very nice...great job btw...you might want to wrap some elec. tape around the top part to make sure no water ever gets a chance to get in there to short anything. I went with a preorded kit from http://rjminjectiontech.com/?p=7

i got lazy. I have 2 questions though.

1. Do i need to hook up a ground off of the back of the 3G as seen in this diagram?

View attachment 379793

2. and 2, where do I hook up my red/green wire too?
View attachment 379794

I'm splicing and cutting off the other 2 wires on the middle harness.

Do I connect it to 35 or 37.

One diagram said 904. On my '68, the #35 is actually Orange for me, not White. I also checked which ones has power at "ON" and they were 35 and 37. Should I just leave the old volt. harness or can I cut that little bugger out? I might kinda bored and strip out exactly which wires I don't need, but any revealing clarification would be awesome.

this is the only confusing part i have...time for a pully puller tomarrow
 

scrutmonkey

Member
Jan 17, 2003
243
0
16
San Jose, CA
Jun 25, 2007
#7
  • Jun 25, 2007
  • #7
I did the "Quote" thing again, sorry...
 

joesgt281

Founding Member
Oct 2, 2002
163
0
0
Katy, TX
Jun 25, 2007
#8
  • Jun 25, 2007
  • #8
Scrut,

1. I've never seen a ground wire actually used. I think as long as the engine block is properly grounded to the chassis, one would not be needed since that alternator case will have a good ground throug the bolts that attach it to the block.

2. By red/green wire, are you referring to the green w/red stripe wire, wire 904?
Regard my next statement as unproven, but my belief is that this wire is hot with the key on and that this is the wire you need to extend to the new 3G harness's green w/red stripe. This is the way I'm wiring it up on mine.

Oh, and on the pulley puller subject, all you need is an impact wrench. Once you have the nut off, the pulley will come.

Joe
 

scrutmonkey

Member
Jan 17, 2003
243
0
16
San Jose, CA
Jun 25, 2007
#9
  • Jun 25, 2007
  • #9
I assume it is the 904...but it stops at the voltage regulator...do I have to run it all the way to the other side of the bay? It's fun trying to upgrade systems in these, but can get quite frustrating.

Looks like i might have to "borrow" and impact wrench somewhere.
 

joesgt281

Founding Member
Oct 2, 2002
163
0
0
Katy, TX
Jun 26, 2007
#10
  • Jun 26, 2007
  • #10
scrutmonkey said:
I assume it is the 904...but it stops at the voltage regulator...do I have to run it all the way to the other side of the bay? It's fun trying to upgrade systems in these, but can get quite frustrating.

Looks like i might have to "borrow" and impact wrench somewhere.
Click to expand...

yes, you would have to run it over there, unless you wanted to use one of the other colored wires that went to the old alternator that also came from the old voltage regulator. I wanted to be a little color-consistent, so I tapped the green/red wire before the connector at the voltage regulator and ran a green wire to the new alt connector.
 
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