Replacement cable between alternator and fuse box. What cable do I need?

Tried replacing it with a 2awg because sometimes she felt low on power. That was enough to fry the alternator fuse. Replaced the fuse, reconnected that thick cable, popped again.

What gauge do we need? I've been flipping through google and the fsm and it is annoyingly difficult to find this information.

I'm thinking I need a 4awg? Maybe 6awg? It's such a pain to replace the alternator fuse I don't want to have to do it again.

 

It's not the cable. The fuse blew for a reason. A #2 has more rating than the alternator.

 

Interesting. I put the wimpy cable back and it didn’t pop ¯\_(ツ)_/¯

Does this mean I have a short some where?

 

I used 8awg

 

Sounds like it.

 

#8 cable is plenty of cable. You might start to worry a little if the battery was in the back of the truck. As the rating goes up the cable side number gets lower.

 

Okay, so I put in an 8AWG wire. But I’m super confused on the wiring now.

I seem to have an extra cable coming off my battery. Nothing works unless I connect it to the fuse box.
In the photo, it’s the cable between the battery and the fuse box NOT connected to anything.

 

Without being up close and in person no way to tell just what modifications have been done.

You should have a wire from the Positive side of the battery to the alternator fuse ! From the Alternator B terminal to the other side of the alternator fuse . That allows the charging system to work along with the wires connected to the 3 wire alternator plug.

With your new 2AWG cable most likely you had a poor connection causing the fuse to open.

 

is the post at the top of the fuse box the alternator connector?

if so, where is the positive side of the battery supposed to connect with the alternator fuse? Does it use the same post? Is there another post somewhere?

 

Okay I'm convinced I'm doing something wrong.

WTH connects to the post at the top of the fuse box? I thought it was a cable that went to the alternator, but the alternator post is supposed to connect directly to the positive terminal of the battery.

I've been tearing through the fsm. I can find diagrams of the fuse box, but all of them leave that post at the top unlabeled which is super frustrating

For right now, the truck only has power if I bridge the post on the alternator with the post on the fuse box with the positive battery terminal.

EDIT: Spelling

 

You are just not seeing the other + cable attachment point on the fuse block. The unattached + cable you show attaches to the battery side of the fuse block just below the red 30A fuse. IIRC, a screw attaches it to the fuse block. As posted above, that is the + cable leading from the fuse block with the clear 120A ALT fuse to the battery. The + cable from the alternator attaches to the top of the fuse block just as in your pic. Both of those + cables route thru the engine side of the fuse box.

Water break is over so back to work disassembling and regreasing the 27-year-old Warn winch and roller fairlead on my '97 Taco.

 

Without looking I do know many of the connections you need to unbolt the fuse block and access from the bottom side . Both the wire from the battery to the Alternator fuse should be a bolt on connection to handle that high current load.

remove the negative battery cable and start ringing out connections till you find the one from the Alternator B terminal.

 

Maybe that's it. I lost one of the screws that holds the alternator fuse in. Maybe that completes a circuit?

Damn thing fell into the engine bay and did not hit the floor