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As the title says I've got the alternator diode issue and while it's off I'd like to make a new wire from alternator to fuse box. The rubber loom is rotten and falling off causing it to short against spots. I'm not sure where I can find these exact lugs. Fitment in the alternator is pretty tight. 



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While it's off do the W-T wire modification and save yourself some headaches later on.


 Look this over first.

 This is another way to do it.


This is how I did it. 

1  Disconnect batteries


2  Unplug ground wirer, the one (black/yellow) that comes by the alternator, at the aux. battery.


3  Remove the charging wire from the B+ terminal of the alternator.


4  Remove alternator top bracket.


5  Remover the ground and charging wire from plastic conduit removing the 3 clamps as you go.


6  Remove the 10mm nut that holds the charging wire at the PDC and throw the wire in the trash.


7  Cut the ground wire where the 4 wires are spliced into it and throw the old ground wire in the trash.


8  Strip the 4 ground wires an solder the in to a #10-12 1/4" eye lug.  You may have to spread the end of the lug open to fit all the wires be for you solder.


9  Install new 1/2" conduit on remaining wire that are in front of engine and reinstall the 3 clamps. Tape ends as you go with quality electrical tape.


10 Make the ground cable from engine to main battery.  Cut #6 AWG cable 18-20" long and solder lugs on.  I used a small butane torch to do this.  Don't for get to orientate the lugs for minimum cable twist and slid the heat shrink on the cable before you put the lugs on.


11 Attach ground wires and cable to engine case with the 5mm x0.08 bolt an a flat washer and attach other end to main battery negative clamp.


12 Make the B+ charge cable from alternator to the auxiliary battery.  Cut the #4 AGW cable 20" long slide on the heat shrink and solder on the lugs.  The sides of the #4-1/4" lug that goes on the alternator B+ post may have to have its side ground off by a few thousands to make it fit in the insulator.


13 Attach the B+ charge cable to the B+ terminal of the alternator and the auxiliary battery positive clamp.  Refit alternator top bracket.


14 Inspect all work, reattach all battery cables to the batteries and rest APPS.


15 Start engine and test DC and AC voltage at B+ terminal and both batteries. 


A battery shop has the cable and lugs.  The rest of the materials, (solder, heat shrink' cable cover, #12 -1/4 lug, bolt and washer), came out of my supplies, 


2' #6 AWG        $5.54

2' #4 AWG        $5.54

1 #6 -1/4" lug        .47

1 #6 -5/16" lug       .47

1 #4 -1/4" lug        .47

1 #4 -5/16 lug        .47

             TOTAL 12.96




I added a 150 amp fuse to this cable later.

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Posted (edited)

That's awesome. I saw the W-T listed in the forum but wasn't sure what it was. I love the shorter alternator feed. Definitely going to do this. I believe your list is missing one wire lug for the original ground bundle to block. Make a 4ga wire for alternator to aux battery using one of each 1/4 and 5/16 and another 6ga wire for block to main battery ground using another 1/4 and 5/16 lug. 

Edited by Recian426
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3 hours ago, Recian426 said:

I believe your list is missing one wire lug for the original ground bundle to block.

This the #12-1/4" lug I got out of my supplies.  I took the plastic cover off and opened the end to fit the four ground wires into it.  They were then soldered together.

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I have made my own lugs using copper tubing. Cut copper tubing about 1 1/2 '' long and Insert a steel rod that fits in the copper tube while you crimp/ flatten the other end in the bench vise. Then drill the hole for whatever size electrical stud you have.

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