Hello,
I am in the middle of a engine build and decided to do a one wire alternator and eliminate the existing alternator and external regulator box and its wiring.

During this process I have messed around and have lost power to the top 3 fuses on the fuse box “all the fuses that are active when you turn the switch to on: the bottom two fuses that are on all the time still work.

My stupid questions is the fusable link that was in the stock alternator wiring necessary for those three fuses to work?

I am still in the process of tracking down the wires from the fuse box to where they go but I was hoping some one on here has seen this before and point me in the right direction

thanks

 

No, fusible links would not have anything to do with it. It sounds like the alternator is not getting regulated.

 

What wires did you change at the starter relay/solenoid? And was your original regulator wired with three positions, or four positions filled with wires? If you have an ammeter you should have had the three wires. With a BAT light only, you would have had four wires.
I'm trying to figure out what would have changed, since as far as I knew until now, all the power entered the cabin on one single Black w/yellow wire. From there, you have a spliced branch that feeds the constant powered fuses, the Black w/green wire that powers the switched-with-the-key fuses, and then just one or two that get power from other components. An example of that would be the Blue w/red circuit that feeds the dash lights. This is powered through the headlight switch rheostat, into a single small fuse, then out to the bulbs.

Sounds almost like you've had a "coincidental failure" where maybe some old rusty connections on the back of the panel have let go while you were working on it.
How's the rust and wire condition situation in general? Might be worth pulling the fuse panel off to take a look-see behind it.

You have just the five-position panel, correct? Any chance you can post up a pic?
And while you're at it, check the Black w/green wire on the ignition switch. Not sure how yours is oriented, but on the older simple switches there was a long threaded post coming out of the center of the switch. Looked like a ground stud, but was in fact the ACC power supply to the fuse panel and other areas.
Your full-size truck might have had the different model, but either way look for the Black w/green wire and make sure it's intact.

Paul

 

Thanks for your post. I am gonna take some pics. I was in the process of tracking that big black wire with yellow stripe in the cab last night.

I have 5 fuse block.

 

You are awesome Paul.

I tracked it down to the big black wire going to the ignition switch

I really appreciate your help.

 

If one of them is one of those tiny short fuses and is marked "INSTR LT" or something like that, then it's only going to have 12v passing through it when the headlight switch is on to at least the first position.
It's not powered by a main feed, but instead is simply an easy way of adding a fuse to that circuit that originates at the headlight switch and goes out to feed the dash lights.

Anything that's switched, such as heater, radio, backup lamps, wiper, etc, is powered by the Black w/green stripe wire from the ignition switch.

The Black w/yellow wire is to be found in multiple places. One branch originates at the back of the alternator (the big one on the BAT terminal) and runs to the starter relay. This can also be Black w/red, but most I've seen had a yellow trace.
A couple of others are spliced into the main Black wire from the starter relay throughout the vehicle. Here again though, the color could be all Black, Black w/red or Black w/yellow. Guess it depends on which wire color they had the most of that week, but generally anything with Black w/yellow is a main power feed and other constant power wires are spliced from that. Several Yellow wires are used to feed other components. Some Red wires too, and even a Black w/orange to feed the headlight switch.
The headlight switch has it's own built-in circuit-breaker by the way, so is not fuse protected. Only the dash lights have their own fuse, probably because they are too small to trip the breaker?

Anyway, there are lots of places you may find a Black w/yellow wire. But as far as I know, they should all have full battery voltage wherever you find them. If you test any junction points that give you access and they have much less than battery voltage, you're seeing a voltage drop from some resistance of some kind.
On that wire I would hope you'd see within 1/10v of battery voltage all along it's length. But up to a 1/2v drop is probably acceptable in some circles. Less loss is better no matter where you are though.

Paul

 

Hah! Cool, got it while I was typing!

Paul