Let's say I accidentally touched the alt hot to ground... what would I have blown?

[dbreid]

Firstly, I am an idiot. An impatient idiot. I wanted to get my alternator problem resolved quickly, and in my impatience, working quickly, I accidentally touched a wrench to ground (bracket) while tightening the nut on the back of the alternator (the red charging one).

It was only touched for a sec, but I did see smoke from the firewall on the drivers side (cringe...).

I quickly checked the fuses in the box, and none of them seem blown, but I have no power at all when the key is on now, and nothing (accessories, etc) works. I need to go read the wiring diagram and see if there is some master fuse or something, but did I melt the fuse box?

And yes, I am an idiot. Rule number one is never work on anything with the ground strap on, but I only had that one bolt, and I was in a hurry. I deserve whatever my fate is on this one, of course, but if I need a new fuse box, I need to get ordering one as fast as I can!

Thanks,
Dan

 

[bp71k5]

You probably blew a fusable link if none of the fuses are popped. Just check the continuity of the wire that was smoking.

 

[4X4HIGH]

Sounds like you blew the fusible link wire. It is located down near the starter, it actually goes from the starter to the junction block on the firewall. You could also have blown the diode trio or the rectifier in the alternator.

 

[dbreid]

OK, so I'll start with the fusible link. How do I find it, and if it is bad, how do I replace it? Do I need to get a new one? I will pull that out and test it, I guess?

 

[dbreid]

You probably blew a fusable link if none of the fuses are popped. Just check the continuity of the wire that was smoking.

It was hard to tell which wire it was, exactly. I will look for the fusible link and update here.

 

[dbreid]

Also, here's a good link from 4x4High in a different thread:

http://www.madelectrical.com/catalog/fusible-link.shtml

 

[dbreid]

OK, so I started digging into it and I have more questions! (shocking...)

I read the wiring diagram and followed what I thought were the fusible links. I took the pictures below. In reading the diagram, it looks like the thing on the firewall is a "junction box". What the heck is that?

How can I tell which wire is bad? Will it be obvious and totally melted?

Thanks (as always) for the advice!

-Dan

 

[4X4HIGH]

On your bottom pic the wires with that big section in the wire is the fusible link area

 

[dbreid]

So that white "thing" is the fusible link?

Two issues with that...

1.) It "looks" OK.
2.) That wasn;t where I saw the smoke. The smoke came from closer to the "junction box" area in the top picture.

None of the wires going into the fuse box look melted, and there isn't obvious damage, but it isn't the sexiest fuse box I have ever seen.

In my efforts to track the wires down, I also scanned the wiring diagram. Maybe this will help?

 

[dbreid]

Now that I look at it, those white "barrels" must be "what they call "splices" in the image above?

How do I go about testing to figure out what is actually busted?

-Dan

 

[kgblazerfive]

You can just cut out the link and run solid wire but the next time you do it you will melt more

I would rewire it personally to a Ford starter solenoid since you have it down this far. The problem with Chevy's wires is that the power to your truck runs hot all the time to your starter and all you accessories are run off of that power.

The big runs all the power to your truck the little trips your soleniod when you turn the key

 

[kgblazerfive]

That juction box is a link also but its like 40 amps or somthing the links are on both ends of the wires

 

[4X4HIGH]

To test the wire get yourself an OHM meter and check for continuity from one end of the wire to the other end. The one wire goes from the large starter lug up to the junction block on the firewall and is usually the one that goes bad. All you do is find the bad section and properly splice in a new section of fusible link wire.

 

[broncoman6524]

With the key off, check to see if you have power going into that junction block. If not, the fusible link from the starter to that block is blown. If you do check the OHMS from the block to the power on the alternator.

The wiring is actually really simple, power from the battery to the starter soleniond, then to that block. Which runs to the alternator, headlight switch, and the key.

Having to re-wire a whole truck taught me alot...

 

[dbreid]

UPDATE!

It is fixed! It turned out to be the fusible link right at the junction bock, just like you all said! I REALLY appreciate the help and support I get here. I hope that other folks can learn from this thread as well, and that I can help others on this forum with issues as well. Thanks again to all who took time out of their lives to help me. It means a lot to me. Thanks!

-Dan

 

[dbreid]

And just because I love pictures in threads, I updated the picture above to show the one that was actually the issue. Highlighted in green below. I bought a new fusible link from NAPA (they had GM ones for cheap) and everything just started working again!