What is the deal with fusible links? How do I find the short?

Question

I have a 1974 Chevy ElCamino and recently a section of wire running along the firewall shorted out and appeared burned. I have been told two things. One ,that the El Caminos had a problem with these links and two, that there is a short somewhere in the electrical system that caused the link to melt. Now, short of tearing all the wiring out of the car, is there a way to find out what caused the short? So much of the wiring is wrapped up and in protective sleeves, I would hope to be able to diagnose at least part of the root cause without trying to unwrap it all.
I found the link burned after the car just "died". I found a section of the protective wire wrap melted and bulging out along the firewall. It had knocked out all power from the battery. No lights, horn, accessories etc.
But just replacing the link is not enough. There must be a root cause and I don't feel like being stranded again.So I figure that if it knocked out all the electrical, it must be a major circuit,right? HELP!!!

Answer 1

A wiring diagram will show you where the wires go to track down the short---might be hard to locate one for your year vehicle, try a few Chevy dealers maybe---replace the fusible link with an inline ATO type fuse holder (parts stores carry them) and the proper fuse to protect whatever gauge wire the circuit has as a way to keep from blowing and burning fusible link wire. Repair any wires that were burned in the harness and leave them separated temporarily. http://minimopar.knizefamily.net/electrical-links.html
Check all the wiring for signs of burning or discoloration and try to unplug any connectors in the circuits in question temporarily to help track down the short.

Answer 2

It was enough to melt the fusible link, that's all. What you need first and formost is a schematic diagram. You can also isolate the original short by removing fuses and checking resistance as each is inserted to find the low resistance. You will also need to procede from the melted link following the color code against a diagram. Eventually you will figure it out.
I had a catastrophic meltdown in a car with no fusiible link, with smoke pouring up from under the dash. Wires were melted and fused everywhere. I managed to tape it up and get going but it took a long time to replace every defective wire. I still had to open the main harness and make repairs which fortunately have held up now for 7 years--but never know! So you are lucky by comparison.

Answer 3

Fusible links not often ever bypass, so which you would be able to have a ineffective short inflicting a severe amp draw. this could have broken something else interior the circuit or some section failed via shorting. so which you ought to song down the failed electric unit.