OK boys. In doing some work to put in some new cabling, alt, and battery, I clipped the fusible link between the alternator and the battery out of the wire (because I didn't know WTF it was and there wasn't enough cable length left to splice the wires together). So, I've got no fusible link between the alt and battery.

Perhaps because of this, the car alt won't charge back to the battery. So, it seems that now days they don't sell cables with a built in fusible link, rather they sell short lengths of wire with a slot for a regular fuse that you splice in, in place of the fusible link.

How do I know what wire to buy and what size fuse to place in the chain? I see the manual saying "14 GA/Rust" which means a 14 gauge wire that, I think, must be rust colored. Is that right?

What size fuse then? 30 amp, 50 amp?? I don't know and would appreciate any help you can give. I searched the forums and didn't find this information.

 

Yes, 14ga. rust colored wire. You can use any color you like, of course!
Have to look at the wiring diagrams at home for the amps.

 

Please check for that amperage. I've looked at the diagrams in my Chilton manual and it doesn't reference amperage for the fuse.

 

I know in a painless wiring harness its a 50 amp . That in a street rod type harness and a 1 gen camaro harness . Thats the only two i have installed. You could clamp a ampmeter on your wire with it running and all accessories on (radio ,blower,lights )and take a reading .it will get you in the ballpark.

 

Please keep the tips coming! I am still looking at different sources for this information and cannot find it for the life of me.

 

DCJ, It really is easier to splice in a new replacement fusible link than it is to splice in a fuse holder. You can buy them from NAPA with a ring terminal on one end. Then you strip the wires, install a length of heat shrink tubing over the wire, then crimp on a butt connector, slide the heat shrink tubing over the connector, then use a heat gun (or a torch, in a pinch) to shrink the tubing over the splice for a weathertight connection.

 

Maybe I just talked to a donkey at NAPA, but he stated that "we don't sell those" and showed me the fuse holder setup. Maybe I need to try again?

 

Sorry for the late response.
I dont have the wiring for the 86, only the 84 manual. But I dont think it's substanually any different.
In 84 there is one wire that goes from the "Bat" terminal on the Alt. to the + stud on the fender well and from there to the Battery. In 84 it is red and a 10ga. wire. Also from the stud is a small 20ga with a fuseible link that goes to the computor control. There is NO fusible link in the wire between the "Bat" terminal on the Alt. and the Battery.
Also on my 97 it's the same an 8mm wire going directly from the "Bat" terminal on the Alt. to the Battery.

It also states: "Fusible links are used instead of a fuse in wiring circuits that are not normally fused, such as the ignition circuit. For AWG sizes, each fusible link is four wire gage sizes smaller than the wire it is designed to protect. For example: to protect a 10ga wire use a 14ga link. Links are marked on the insulation with wire-gage size because the heavy insulation makes the links appear to be heavier gage then it actually is."

So, because none of this matches your discription of the wire I'm naturally a little confused.
Your Alt. should have a single stud on the back (marked "Bat") with the wire that goes from this terminal to the battery. On the side it has a connector plug with at least two wires and a jumper that goes aft into the engine harness.

 

Thanks Z28SORR. Yes, my '86 seems different. There was a fusible link between the alt's positive post and the positive battery terminal. The wiring right around it was frayed and corroded and, again, I clipped it out not knowing what it was.

Good news is that I found actual fusible link replacement parts at another auto parts store. According to my Haynes diagram, it's a 14 gauge link by the battery and 16 gauge at the starter. I got both thinking that the one under the car might be bad as well (they're $4 a piece). I started to put the 14 gauge in, but didn't have the proper crimp to put it in so I had to stop.

But finding this relieves the question of "what amperage" and I'll be interested to see what happens when I get this in.

 

I should have added, that I dont think the lack of a fusible link is causing your Alt. NOT to charge the bat. It's just a circuit protection devise, it doesn't change the way the system operates. Have you had the Alt. checked?
OK, this is just my personal opinion. But I dont see the need for a fusible link in this wire. I have to wonder, if GM didn't have them before and dont have them now, why? I personally think it's because they're more trouble then they're worth.
I would go to the auto parts and get a nice new 8 or 10 gage wire with "good" crimp type eyelet, for the Atl. end, and replace this entire wire without the fusible link. Use heat-shrink for both the crimp at the Atl. and the splice at the battery. And cover all with that small diameter plastic wire wrap.
Good Luck!

 

I have a new alternator, new battery, and new positive battery cable in place. That still didn't fix my alternator not charging the battery problem. And yes, both the OLD and the NEW alt bench test just fine.

So, in the process of the new alt and checking the wiring in the circuit, I saw the corroded wiring near the fusible link and replaced it (clipping out the link). So, I am trying to put the wiring back to spec and right now the problem area is that I have no fusible link. I may still not be charging back to the battery after I replace it, but that takes one thing out of the equation.

There isn't much else left in the charging circuit that would be wrong.