Distributor, Ignition Coil, and Ignition Switch wiring

[AndyMenon]

Hello,

Here is my distributor wiring set up. I need to confirm where the 2 pink wires from the harness go on the Ignition switch. From what I understand, the coil has to be energized when the ignition switch is turned to the IGN position. But when the motor fires up, and the ignition switch returns back to ACC position, how does the coil continue to remain energized? I have the sketch below.

thanks,
Andy

 

[2old2fast]

No idea what ign. switch you have , but my switch ,ign. is hot in start & run position , off in acc position . Key "up" everything off , key left =acc., key right=ign [run]. key far right =start ???

dave

 

[PotvinGuy]

Whose harness? Did it have instructions? The nomenclature is odd; I've never seen an "engine" wire.

 

[Wild Mango]

Older ignition systems used a ballast resistor to limit coil current in the primary. When cranking, a separate wire, usually part of the starter solenoid circuit, by passed the ballast resistor giving more coil current when starting.
As your note says, you don't need any of this resistor stuff, and your IGN terminal should power the coil on and off, is all, via the appropriate fuse

ACC has nothing to do with the ignition circuit

 

[AndyMenon]

No idea what ign. switch you have , but my switch ,ign. is hot in start & run position , off in acc position . Key "up" everything off , key left =acc., key right=ign [run]. key far right =start ???

dave

Yes, my ignition switch is something like what you're describing.
Key up- everything shutdown
Key left -accessories come on
Key right -accessories come on
Far right - spring loaded ignition

 

[AndyMenon]

No idea what ign. switch you have , but my switch ,ign. is hot in start & run position , off in acc position . Key "up" everything off , key left =acc., key right=ign [run]. key far right =start ???

dave

It might be a misprint. It may actually mean IGN SW IGN.
I bought the harness a few years back, but is pretty good.

 

[AndyMenon]

Yes, my ignition switch is something like what you're describing.
Key up- everything shutdown
Key left -accessories come on
Key right -accessories come on
Far right - spring loaded ignition

I just went down to the garage and checked.The ignition switch is hot when it gets back to "RUN" position from "IGN".
Now begs the question, which of the 2 pink wires goes to which terminal on the Ignition switch.

thanks again!

 

[PotvinGuy]

Really need to know the labeling on the 2 pink wires. Neither of them sounds familiar. Trace the pink wire from the coil (what is its label); it wouldn't surprise me if it is the pink wire labeled IGN SW COIL, in which case I'd hook it to the IGN post. Then trace the other pink wire and see where it goes. Let us know.

Is there a wire from the harness to the battery? Gotta get power somehow.

 

[2old2fast]

Only thing I can guess is : 1 pink wire [ign./coil ] goes from switch to coil while the other [ign/engine] means starter to coil ??? [which would br impossible w/ a 2 terminal starter !! [aftermarket non gm]

dave

 

[AndyMenon]

Only thing I can guess is : 1 pink wire [ign./coil ] goes from switch to coil while the other [ign/engine] means starter to coil ??? [which would br impossible w/ a 2 terminal starter !! [aftermarket non gm]

dave

Hmmm. The wiring harness comes with 2 plugs, one clear plastic, and another Black plastic.

The Black plastic has the IGN SW Engine wire going to it. Another wire is a Red power wire, that is split between the black plug, and the clear plastic plug.

The clear plastic has the IGN SW Coil pink wire running to it. As you said, this wire is for the coil, that makes complete sense.

I unmounted the fuse block, and traced the pink wires back to it, and it so happens that both these pink wires originate from one single 30A fuse . It looks like, I have to ignore the 2 wires in the black plastic plug- either strap then under the dash, or cut them off and "blind" crimp the wires.

thanks,
Andy

 

[AndyMenon]

Really need to know the labeling on the 2 pink wires. Neither of them sounds familiar. Trace the pink wire from the coil (what is its label); it wouldn't surprise me if it is the pink wire labeled IGN SW COIL, in which case I'd hook it to the IGN post. Then trace the other pink wire and see where it goes. Let us know.

Is there a wire from the harness to the battery? Gotta get power somehow.

Yep, there is another wire that goes from the fuse block to the (+) side of the coil. This is how the coil gets power.
The entire fuse block has a thick red wire leading out of it. This is definitely not a 10 Ga, but a lot thicker. I've confirmed this is the power wire during the course of the wiring. The headlights are not hot if I don't connect this wire to the battery.

I did trace the 2 pink wires, and I've described it in my reply to David's post here .

Thanks,
Andy

 

[PotvinGuy]

Ah, so there are only 2 pink wires, not the 3 shown in your diagram? You're right, one of them (either one) goes to the coil, and the other can just be ignored.

 

[AndyMenon]

Let me check AM tomorrow and make sure.
Thanks,
Andy

 

[AndyMenon]

OK folks. Some old fashioned testing has given me some answers. The only flip side of the issue is that I had to unmount the fuse block to make sure that I know where the wires go. Here is my new Coil wiring diagram after I tested it with a multimeter.

Not sure, why the fuel pump wire is named IGN SW Coil, but I guess the manufacturer decided to reuse a piece of wire from his bin and forgot to alter the labelling

Andy

 

[railroad]

You may have this issue covered and I could not confirm by your diagram, but the fuel pump needs to be key on activated or on a switch. I am sure you have or will address this as you would not want it hot all the time. Also you may consider a high amp fuse link coming off the battery before the switch and fuse panel. Autos ran without these for years, but it could save you a melt down if something did go wrong. Never mind, saw your other post and looks like you are doing good on all bases. good job.

 

[PotvinGuy]

Mercy, that is one strange harness. Wonder where the the two plugs were supposed to go?

You might consider taking the 12v main power from the ACC post of the ignition switch instead of from the battery. That way, all power is off when the key is off. Otherwise everything (lights, horn, wipers, radio, death ray) would still be operational.

 

[AndyMenon]

You may have this issue covered and I could not confirm by your diagram, but the fuel pump needs to be key on activated or on a switch. I am sure you have or will address this as you would not want it hot all the time. Also you may consider a high amp fuse link coming off the battery before the switch and fuse panel. Autos ran without these for years, but it could save you a melt down if something did go wrong. Never mind, saw your other post and looks like you are doing good on all bases. good job.

Wow, thanks for the great review ! I'm glad that my work is being vetted by so many experienced members here!

Andy

 

[AndyMenon]

Mercy, that is one strange harness. Wonder where the the two plugs were supposed to go?

You might consider taking the 12v main power from the ACC post of the ignition switch instead of from the battery. That way, all power is off when the key is off. Otherwise everything (lights, horn, wipers, radio, death ray) would still be operational.

Right! That's an excellent point. At this point in time, this circuit is soft wired. I can change this from the BATT to the ACC.

But one question? The universal ignition switch has very stubby terminals. I don't think a single terminal can hold more than 2 wires.
I could use a distribution block but the space under my dash is already full with a fuse block, an ignition coil,and 5 relays. How do I get around this issue?

thanks
Andy

 

[PotvinGuy]

I just splice two or more wires down to one. I don't use crimp splices, but instead solder the wires and cover the joint with shrink tubing.

 

[Wild Mango]

Best practice to have only one wire per terminator (i.e. crimp lug, spade terminal etc.) so you can isolate individual circuits in the future. Distribution block doesn't have to be right there at the switch, can be somewhere else handy. Keep in mind if you run everything from the ACC terminal (which is a good idea, as Potvinguy says), you could well exceed the current rating of the switch, in which case a relay (which you already know about) is indicated.

BTW most ignition coils generate a bit of heat and its a good idea to mount them somewhere well ventilated, or even out in the breeze. As a general rule, keeping the High Tension (high voltage) leads as short as possible is also a good rule, especially the HT from the coil to the distributor. You might consider re locating the ignition coil, which will free up space for the ACC relay and terminal block thereof. JM2CW