Help in northern VA SBC 76 fj40 wiring (1 Viewer)

[hanzo111]

I'm buttoning up my 76 fj40 project and need a little in person help. Anyone have experience
in wiring sbc with 1 wire alternator in a 40? I have seen and read every diagram but I still
have some questions.
My truck will run but not shut off with ignition switch, I have seen a diode and dummy light mentioned
but I am not wiring savvy enough to get it right, Also I have a question about the thick white wire and where it connects to.

I'm in great falls, if anyone has time to come and share their knowledge a case of beer is waiting for you.

 

[B y r o n]

Start with post #8 here.

 

[CondeCruiser]

Post this in the Capital Land Cruisers in the club section.

North American Clubhouses - East Region

East of the Mississippi River

forum.ih8mud.com

 

[peesalot]

That happened to me too. I forget exactly but it was a wire that was backfeeding when ign was shut off, something abou tthe alt output wire & where it ties back in to charge the system, take the alt output straight to Batt and see if that solves, IIRC you then have to run power to volt meter as I think thats where the alt ties in stock, I think. to test just remove alt output at back of alt, start it on batt and see if it turns off with no alt output, then you'll know what your chasing.

 

[bkfj40]

I would pick up a small light and the. Put that in the dash of there is a spare hole or put in the engine bay. I do not know if a led light has enough resistance.

 

[hanzo111]

 

[pb4ugo]

Its hard to tell in your video. The large terminal/wire on the alt goes to the + side of the batt. This connection makes the Ammeter not work. You can disconnect the wires at the ammeter and connect them together. You are correct, the 1 wire goes to the idiot light. The large white wire coming off the stk harness goes to the + side of the batt. It now supplies power to the fuse box. I would install a fusible link then hook the white wire to the + side of the batt. The white/blue stripe wire is no longer used.

The Mad Electrical website has good tutorials on this subject. I'm using the batt as the junction block. This is not really a 1 wire set up but most folks call it that anyways.

 

[pb4ugo]

you should disconnect the stk voltage regulator.

 

[hanzo111]

I have connected the white wire to a 30 amp fuse

All of the diagrams for the SBC Conversion state that the white and blue go to the alternator should I just cap that off?

 

[pb4ugo]

Stk wiring the white wire(Batt) goes to the + side of the Ammeter & the White/Blue is on the Neg side of the ammeter, it goes to the fuse box. FYI. Power passes thru the ammeter and the meter has + & - on it so it can be hooked up correctly to show charge and discharge. When you run a charge wire from the alt big terminal to the batt you make the ammeter not work. I bypassed the ammeter by disconnecting the wires on it and then connecting those 2 wires together. 1 is the white wire from the batt and the other is the white/blue stripe and it goes to the fuse box. You don't need the white/blue wire at the alt. I put an insulated Butt connector on it, then taped it too, to terminate it so it won't ground and then taped it up into harness. In the pic the blue wire goes to the idiot light. I used the Brake light in the dash. The light needs to be connected to a wire that is hot with the ING on.

 

[pb4ugo]

I prefer to charge the Batt directly from the alt.

 

[hanzo111]

OK, I think i have it. (im a bit slow)

1. alt plug wire number 1 to diode to dummy light to switched ignition
2. alt plug withe 2 back to alternator main lug
3. white wire to fusable link battery
4. blue white wire capped off
5. alternator main lug to battery

done?

 

[jhsmith]

I'm buttoning up my 76 fj40 project and need a little in person help. Anyone have experience
in wiring sbc with 1 wire alternator in a 40? I have seen and read every diagram but I still
have some questions.
My truck will run but not shut off with ignition switch, I have seen a diode and dummy light mentioned
but I am not wiring savvy enough to get it right, Also I have a question about the thick white wire and where it connects to.

I'm in great falls, if anyone has time to come and share their knowledge a case of beer is waiting for you.

I can help you if you are in Great Falls, Virginia (not Montana). I live there as well. Just put one in my '75 FJ40. PM me.

 

[pb4ugo]

For #1 This article below is helpful. I learned someting new. It's better to hook it up to the accessory side instead of the ignition side. Both are hot with the key on, the accessory side will prevent any feed back to the ing. This will insure the engine turns off. I personally prefer the light. On #5 you should use a 10ga or numerical smaller #(larger diameter wire). I used a larger wire because of alt output and the winch.

3 wire alternator feedback car wont shut off with key

A big Thank you to H.A.M.B. and its members for the help in solving this problem. I spent a fair amount of time searching the board to figure this out...

www.jalopyjournal.com

 

[hanzo111]

Getting there. Yesterday I diagnosed a bad ignition switch. We will see next week