wiring questions

[rebars1]

1985 chevy v8 5.7L

1. What voltage should I read at the heavy red wire at the alternator when the engine is not running? Same as the batery, or 0?

2. In the picture attached there is a gray wire that starts at the fuse (on the right side of the picture) but is not currently connected at the other end, but has an eye connector (you can just make it out on the left side of the picture by the valve cover). Should it attach to the engine for a ground?
http://i23.photobucket.com/albums/b365/rebars1/wire1.jpg

 

[Coors]

Re: wiring questions

I think no voltage at red and black exciter, only at the large wire. Gray is usually tach.

 

[Reel Poor]

Re: wiring questions

If it originates from a fuse it WILL NOT be a ground wire.

 

[Coors]

Re: wiring questions

does tach work? that gray wire is close to neg on coil, where it may go.

 

[rebars1]

Re: wiring questions

The tach does not work correctly. It reads only about half of what it should. I am trying to get it to work rigth. The gray wire to the tach is a different one from this one. It starts at the coil. Here is better picture. Also, here is a picture of the alternator.

http://i23.photobucket.com/albums/b365/rebars1/5876040-R1-028-12A.jpg

http://i23.photobucket.com/albums/b365/rebars1/5876040-R1-020-8A.jpg

 

[Coors]

Re: wiring questions

Don't know, but on your 2nd pick, that red wire is close to failure

 

[rebars1]

Re: wiring questions

Good eye Coors. Thanks, I'll fix the wire, and ponder the rest....

Upon closer look, the first wire I was asking about starts at a relay (Volvo 841177), not at the fuse.

 

[Reel Poor]

Re: wiring questions

Is this what your calling a fuse? It's a relay. I'm not sure but I think that is the starter relay or the way they bypassed the resistor wire for full voltage to the coil when that motor had a point set up in it. The yellow wire with the red strip come from the ignition switch, the red is 12 volts, the black wire is ground and the grey wire either went to the starter selonoid energize terminal or......it used to go to the ignition coil + terminal to supply a full 12 volts to the coil when cranking.

 

[rebars1]

Re: wiring questions

You are correct, ReelPoor, on the relay. I had noticed that in my last post. There are two yellow/red strip wires, a red wire that goes to the fuse, and the gray wire. There is no black wire. It is the topmost wire at the relay in the picture. The other end of that wire has the eye terminal by the valve cover. It's size made me think it may have been bolted to the engine at one time.

 

[rebars1]

Re: wiring questions

Also, I am not sure what the relay is for now, or if it actually functioning. There is a separate starter relay/solinoid. Reel Poor, with the electronic ignition, is the relay still needed?

 

[Reel Poor]

Re: wiring questions

I really don't know how its wired. You would need a wiring diagram to see how it should be wired.

Is that grey wire and one of the yellow/red wires comming from the same terminal?

One of the yellow/red wires comes from the ignition switch and the other yellow/red wire should go to the starter solenoid. With it wired that way it takes the load off the ignition switch and allows the relay to do all the work. You could disconnect the relay and see if the engine will still turn over.

I really believe the grey wire originally went to the coil positive terminal to supply full 12 volts to the coil when cranking. With the ignition system your running you shouldn't need the grey wire.