The Stovebolt Site Forums The Shop Area The Electrical Bay A quick question regarding a stock rewire

I recently purchased a stock rewire kit for my 46 1/2 ton with a generator. Chevys of the 40’s had it. What I got for instructions are 3 pages of xerox copied diagrams (2) and one page showing wire destinations and the corresponding number. Nearly half of the page with wire numbers is unreadable so I don’t know what goes where for some of it. I’m not electrically inclined so this is a problem since I can’t read wiring schematics.
I did ask them for a better copy which I was told would be emailed to me. Didn’t happen.
Does anyone have a clear copy from a past job? There are also wires with letters on them and the page only seems to address numbers on the wires and their respective locations.
Thanks for any help.

Do you have the part number for the kit? You may be able to download the instructions from the web site.

I doubt that Chevs of the 40's made the harness. Might be able to figure out who made it and get better support from the source.

I’ve searched their site for that kind of literature. Couldn’t find any. They didn’t offer anything about the site either while I had them on the phone.

They sell several variations of harnesses. I think you have to tell us which one you bought.

Wiring Harness, Main - For Generator And Turn Signals - Plastic Covered Wire - Chevy Truck

So this one:
https://www.chevsofthe40s.com/detai..._Signals_Plastic_Covered_Wire_Chevy.html

I see the problem. They have provided a link for instructions for a harness with an alternator.

Bob, I did a little digging on the web to see if "Chevs of the 40s" had a different set of instructions with one of their other harnesses, but no luck - Booo! Seems like the only option may be another call to them to note the wrong file is attached to the product page and ask for a copy of the correct document. Wishing you the best of luck in your next call to them.

I do have that sheet as well but there’s another similar to it for generator trucks. That’s the one that is horribly copied so many times it’s unreadable. And it doesn’t include the several wires that have letters on them and where they go.

It might be tough to do, but if you can identify one end of the wire (such as the ammeter connection end,) you could use a multimeter (or powered test light) to "ring out" the opposite end of that wire. Clip one meter probe on the known end, and then touch every other wire with the other probe. When you get the beep (or light), you'll know that's the other end of the same wire.

If you have specific spots you can't ID, list them, and maybe someone with an original wiring diagram can help you figure it out.

I'll keep that in mind when I get into it all, thank you. I get the feeling it's going to be a bit of a mystery for several of the wires and over time I'll figure it all out. I can connect all of the important ones that make it run though in the meantime. I also realize I have to figure out how to remove the gauge cluster from the dash... yay.

It's starting to look lie your situation is quickly approaching the point where you're in danger of getting a "positive smoke test" with some incorrect connections. A battery has a massive amount of current available- - - -several hundred amps are on tap in a "dead short" condition. One wrong circuit can cause a meltdown that can destroy the wire harness, or at least a good sized portion of it. I'd strongly suggest getting some professional help from someone who understands basic electrical wiring and how to trace circuits such as the power supply and charging system circuits . Those are the ones than can cause a meltdown with a wrong connection- - - -and the damage can happen in the span of a few seconds. Good luck!
Jerry

Yeah, I agree with Jerry. DO NOT connect the battery until you've checked out the connections and are absolutely sure they're correct. Learning circuit diagrams can be good, but spoiled in just a few seconds. That's why I suggested using a powered test light or ohmmeter. They don't have enough power to generate a "positive smoke test."

Jerry, Klhansen, thanks for the tips. I will absolutely take safeguards to prevent trashing my harness. I have friends that know stuff electricalish... And so I'll consult them during the install.
Have either of you removed the gauge cluster on a 46 pickup? I've been feeling around in there, losing skin and blood, and can't seem to find the fasteners that hold it in.
Thanks
Bob

And be sure to install light bulbs in every socket before energizing the system, once saw a new harness go up in smoke because of that….

A bright light and a mirror is a lot better way to find those fasteners that poking around sharp stuff in the dark- - - -with your hands!
Jerry

I looked on EPay for a picture of the gauges and found this one. It appears to be one on each end.

1955 1 Series, That is a good reference, thanks. Now I know what to feel for. With a flashlight and mirror of course. Lol

Glad I could help.

Bob
One “tool” I found a game changer was to make a platform to lay on while working on all the under the dash tasks. It sure helped my old back. The platform is a piece of plywood about 40 inches long and about 12 inches wide, custom cut to fit between the seat pedestal and toe board sheet metal. The board lays flat on the floor board and sticks outside the cab about 20 inches and is supported on the outside by 2 legs. It helped to add a thin “mattress” on the platform for added comfort. Unfortunately, I apparently didn’t shoot a photo of the one I made.

As for the wiring. I experienced a similar problem to yours, except the new harness was of unknown origin. It came in a bag without any instructions, that along all the other parts and pieces of my project. As the others have urged and I agree, the ohm meter is your friend.

It helped to lay out the whole harness on a work bench and do as others suggested to trace each wire using the ohm meter. The
wiring diagram in the ‘46 Chevy Truck Shop Manual provided helpful guidance in deciphering wire application, such as head and tail lighting, horn etc. and routing.

Note to self. Chevs of 40's has the worst instructions I have ever seen, even if you could read them.

The good news is you have the simplest wiring job there is. If you told us the "letters" on the wires and good scans of your unreadable instructions, we would have a fighting chance to cypher it all out for you. Also, you may not have to take out the cluster just to wire two gauges. Even though It looks like only two nuts, if not rusted on so bad that you break off the stud and then you are in a heap of trouble. Also, You would have to disconnect or drag out the speedo, temp and oil pressure tubes. Many of us have learned to spot these death traps.

Wire the gauges and bulbs in place. if at all possible. If not, spray the nuts/studs with penetrating oil and drop the cluster down, or out, for access. Work the nuts back and forth and gradually unthread. I think the bulb sockets just pop out and will hang down for rewire.

I'm not specifically familiar with a 46 cluster mounting, going by pics.

Many versions on the market. This is one of the less costly ones. Dash Surf Board

Mark, Figures *you* would know the right tool for the job! I just ordered a complete new harness for the '49 from Jim Carter. I *will* be looking at the Jegs site next.

Thanks!
John

Thanks folks. I’ll likely remove the cluster (cautiously) because it has some rust issues from a leaky windshield seal. While it’s removed I want to try and get the speedometer, temp, and one other gauge working again.
I’ll try and get some pics of the lettered wires that the instructions do not make mention of.

That dedicated platform is OK, but I've found that a sheet of 3/4" plywood and a concrete block works just as well, and leaves more pocket change for essentials like hotdogs and beer!
Jerry

'46 harness is pretty basic compared to modern wiring. I'd lay it all out on a bench and figure it all out with what you can see on your diagram, and service manual, compare with lengths etc. isolate the unknowns and chase down the ends with your meter. Once you study it out and have it labeled so that you have understand it, it won't feel nearly as overwhelming as it does when you drag it out of the box. Relabel with blue painters tape and a sharpie that you can tear off later if it helps you. (it always works for me) After you've got it all figured out, THEN install. And that will help with the "smoke test" that Jerry is referring to! There's just not that many circuits in a '46 when you are staying original. AND as always, it's great to be good, but a little LUCK never hurts, so good luck.