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On this episode of what did I screw up today...

1.4K views 11 replies 4 participants last post by  indy2000  
#1 ·
I was working on the 91 and decided to do the 3G alternator swap while I was at it since I have the parts on hand. I cut the green and yellow wires and they dropped and hit the alternator body. I forgot to disconnect the battery.... Yes I know.

The started solenoid made a funky noise and there was a little bit of smoke. I disconnected it at that point and got everything done. It starts right up and runs well BUT the volt gauge is not working now or at least showing low near the bottom and it should be at the top. I will check idle voltage in the AM but what did I screw up? Did I toast the gauge? The new alternator shouldn't be friend by that, correct?

I cut the 2 black wires and tied them together and crimped a ring terminal and soldered and put that on the post on back of alternator.
I also ran a 4ga wire from that little post over to the large left lug of solenoid and installed a 175 amp fuse. The car starts and runs but the gauge is off now.
 
#4 ·
@indy2000

Man, I am glad you are still around here!

I just checked and at the battery it is showing 12.10 at idle and revved it jumped to 12.3

I just remembered I got this on amazon as a "Warehouse deal" so it might have been returned. I looked around and I don't SEE any visable damage to the fusable links near the solenoid. Not sure that is possible though.

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#6 ·
@indy2000

I was thinking it was the alternator but I swapped in another one today and the voltage is still showing 12 volts at idle at the battery and gauge. I honestly don't know how to test fusable links but I'll Google it. I looked up the links from the starter solenoid and I see online that there is a "green 14ga fuse link for 2G alternator" could that be the one that I fried you think?
 
#7 ·
A "fried" wire ( or blown fuseable link) is pretty easy to spot, most of the time. The plastic insulation covering the copper wire will be melted. Sometimes the wire inside can be burnt in two without obvious signs on the insulation, so you have to either ohm test the wire or feel it with your hands and see what feels "limp" compared to the rest of the wire. It is at that point that a break will be in the wire. A wire diagram is ideal to have so you can find out what color wire it is and were it starts and where it terminates. A DVOM is a must, plus the knowledge of how to use it.
 
#8 ·
I was reading that fusable links aren't really easy to ohm check as a single strand might throw it off or something to that effect. The green fuse link wire from the solenoid, I don't see where it goes? Also, I kept the 2 black with orange tracer wires and tied them together and put it on the back of the alternator. I am now reading that I can remove those and the fusable link they go to at the solenoid? Since I installed the new 4GA wire I mean.
 
#9 ·
take the end of the fuse link, place a LOAD that you can see...........lets see, maybe a light bulb?

what, they make test lights..........




AND, what did you find that made you think you needed new alternator?

is it just easier to install one, then testing its inputs?
 
#11 ·
I pulled the battery to clean under it anyway and to give myself some room to work. I found a break in the wiring/fusible link as pictured. So, question as I am not well versed on this. From the factory, they have the heavy gauge green wire/fusible link with a ring terminal on the solenoid. You follow it down and it branches off to a 18ga fusible link then on to the yellow/white wire that goes to the alternator regulator. The other branch of that wire goes to the black/orange wire that is no longer needed as I replaced it with the larger 4GA wire.

My question is: Can I cut all of that off and run an 18GA fusible link straight from the yellow/white wire and go directly to the solenoid? That would effectively bypass the orange/black wire that is no longer needed and would still keep an 18GA fusible link to the solenoid to the regulator to allow it to charge.

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#12 ·
YES!

while you have access, i would inspect all links, test light, piercing tool.

Also, does your batt light in the cluster come on during bulb test?

if that circuit is NOT complete, green/red wire, you will get NO charging.

Use a test light!!, dont rely on visual