The Stovebolt Site Forums The Shop Area The Electrical Bay Generator and wiring harness

Hey, so not gonna do the smoke test. Quick question.
My original wiring harness forward for my 235 had 2 wires going to the generator.
I have a replacement wiring harness with the same 2 wires (1 larger than the other) same as before but I've
upgraded to an Alternator. Do I go back to the fuse block for power? What to do with the 2 terminals?

Those two wires go to the voltage regulator which you will no longer be using. Remove those wires.
Your alternator needs a 10 gauge wire coming from the ammeter. This goes to alternator lead which has the 10mm nut on it.
Any other wires required for your alternator will depend on which alternator you have.

Thanks Carl. So I am trying to understand, here is a pic of the old wire and where it went.
The 2 wires to the GEN. These wires I can eliminate?

Those 2 wires go directly to the regulator. You will not use them. You could use one of them if you are going to use an alt. with an external regulator, which I dought if you will.

George

Guit-you may want to check the tech section. There are a couple explanations you might find helpful.

That smaller gauge wire is the field wire coming from the regulator. It basically switches the generator on and off to control the output which is the larger wire. The large gauge wire is switched by the regulator and the circuit then goes to the battery to charge it. You could use the large wire with an internally regulated alternator by splicing the two together where they connect at the regulator which wouldn’t be needed.

10-4 gotcha.

Another wiring question. I have run my wires down the frame for the rear lights.
Y/B left side LtG/B right side. They both go to the rear light pigtail(s).
Which is has one Black and one white wire coming from it.
Does it make a difference with the colored wires, which goes to black and white?
thanks

Yes, it makes a difference. Your bulb has 2 filaments; one for brake/turn and one for running lights. Put a bulb in the holder, switch on the lights and touch the wires together to confirm you are connecting to the correct filament (black wire or white wire).

How would I know which is the right filament? Thanks

I have the double filament bulbs

The brightest of the two filaments is the turn/brake signal. Test by touching the black wire and then the white wire to the power. You can see what the brightest filament is and identify the wire for it.

Thanks. I can do that. I won`t have the blinkers ran just yet , or the brakes confirmed.
I was thinking having the running lights on , those should be the dimmest?
Brake ...would be both filaments being brighter? Just gusessin. thanks!!

Turn on the headlight switch to the parking light position.

Touch the left side B wire from the front to the left side B wire on the lamp. Note how bright the light is.
Touch the left side B wire from the front to the left side W wire on the lamp. Note how bright the light is.
The left side B wire from the front connects to the dimmer of the B or W wire on the lamp.
The left side Y wire from the front connects to the brighter of the B or W wire on the lamp.

Touch the right side B wire from the front to the right side B wire on the lamp. Note how bright the light is.
Touch the right side B wire from the front to the right side W wire on the lamp. Note how bright the light is.
The right side B wire from the front connects to the dimmer of the B or W wire on the lamp.
The right side Lt/G wire from the front connects to the brighter of the B or W wire on the lamp.

Yes, running lights use the dimmest filament. Both filaments are on at the same time only if the running lights are on and the brake pedal is pushed or turn signal is flashing.

OK I have the rear lights on/off with the light switch at dash. Those wires turned out to be the
BLUE wire Right side(power) and YELLOW wire right side power .
Brown and Light green have no power. I`m checking all this with a light.
Those two maybe the brake light wires?? I have a new switch mounted.
I have closed the barn so I can see if the brake lights come on and they don`t.
So something is off. I guess if I connected the 2 brake light switch wires, that the brake light would stay on?

Brake/turn signal filaments are brighter than running light filaments.

Ed

Yep, that I knew. Is there power to the brake light switch constant?
Like a dome switch waiting on ground for contact.

Next question: Do you have turn signals? Makes a big difference when dealing with rear brake light.

If you have turn signals, are they stock GM or add-on like Signal Stat?

You know Bill, I was just mulling that over and recollect dealing with that same problem
on my 58 rewire. That the loop between all that (blinker, stoplight) has to be connected.
Since both brake and turn work together back there.
But no I do not have that final harness connected. I should have the blinker wire assembly this week.
Stock GM 58 Column and blinker assembly. The wires down form that will all be new. M+H. But stock.

The brake lights run through the turn signal harness. They won't work without the turn signals hooked up.

I have my turn signals working except for the front Drivers side. Its an original GUIDE light
and only has ONE spade for running lights. I am guessing since it does not have 2 spades like the other
side ,the DS blinker will not work. Is there a way to get the single spade light to act like a double spade?
Edit I went out and checked it all. I have dome light only with the light switch pulled put.
Dimmer and cluster lights all work. brights , turn left and right blinkers ,panel lights.
Front running lights work , just one side works with the blinker. (thats cause of one spade?)
Brake lights work at the rear of the truck , blinkers L+R. ,
But no rear running lights with the switch pulled out 1/2 or full.
So I have that problem and the dome light only working with the switch pulled out.

Ok, can you guys help me with the question of should all four wires running to the rear
of the truck have power all the time? I`m guessing they should. Or should one set of 2 only have power
with the key on?
Not the light switch itself . I had another and the same issue. Something is odd with the black wire for
the tail lights leaving the light switch.

Should be no power on any of the 4 wires until you turn on the headlight switch, press the brakes and/or hit the turn signals.

Thanks Bill. So then with brake pedal down , light switch pulled out ,power should be to all 4 wires to the rear?

After a few attempts. I traced power down to behind the bulbs with the lightswitch out. So the rear running lights should work.
Still no rear running light. Replaced bulb with one from my 1959 , same thing.
Ground should not be an issue cause blinkers and stop light work as they should. If I switch the wires , I have no blinkers and no brake lights but the running light works but too bright.
I don't know.

Yes, assuming the turn signal switch is in the center position.

That sounds like a short in your parking light wire. It sounds like it is grounding through that short instead of the housing.

Check the socket, it might only be shorted when the bulb is in and pushing on the contacts.

Thanks! Yes I think it could be the socket. Its the original housing and I`ve cleaned them really well and
restored it as best I can. But both sides shorting out is not likely, but possible.
With a test light, light switch out and bulb out I have 12 volts at the socket.
Switch in ..off. Seems like it should work. I`ll inspect the socket better.
Now that I think about what you said about the socket ground, I`ll check something 1st thing Monday

It has do something with ground not passing thru the light housing to socket.

All right alls good. User error.
I did not have the boot seated and socket turned in all the way and turned.
All lights work everywhere. As they should.
Only thing left is the license tag light. I can run that to the other terminal at the light switch?
There are 2 at the black wire connection.

I generally tie the license plate light to the running light feed on whichever side of the vehicle is closer.

It is only mandated to be on when the headlights are on.

Success. I ran a wire from the switch(Black-Taillights) down the frame to the tag light.

So is this a done project now (the electrical)? Or do you still have some other lingering issues?

Its all good. I`ve ordered a new front light with 2 spades to solve the front turn signal problem.
Thanks you guys!

I wish I had known that I could buy front housings for dual filament bulbs. I ended up building my own. They work, but were a lot more effort and not really any cheaper.

It is good to hear that you were able to get it all together.

Thats what I saw , the socket would not accept a dual filament bulb, Offered when turn signals were optional?
To save anyone some time mixing and matches to find the right wire color to the rear of a truck at least the 58/59.
Likely other years are the same but it goes down the frame

YELLOW Left side to pigtail BLACK
BROWN Left side to pigtail WHITE


GREEN Right side to pigtail WHITE
BLUE Right side to pigtail BLACK

this bit of info would have saved me much time.