My first engine “build”

Alright, went to turn the key today. It cranked! …in the key Run position…😬

I have a wire in the wrong place and I think I know which one. But I’m not sure where I should have it run. The S terminal on the Starter Solenoid. That needs to go to a wire triggered by the start position on the key ignition. I’m thinking it’s on a switched 12v source. That being the 12ga. Wire off the HEI. I have it spliced into that and I don’t think that’s correct. That’s going to be constant power in run.

So, where is my start signal to come from?
 
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So, what had wrong in the wiring. I followed a couple of YouTube Univ. videos on how a couple of guys wired their 4.0 with HEI… apparently there’s a different or I just got it wrong.

I had ignition start wire coming out of firewall and spliced out to S terminal and run into 12V feed on the dizzy. Then I had the tach wire from the dizzy going to the I terminal.

Don’t ask me why, just understand that I’m mentally handicapped with wiring.

After trial and error and plugging and unplugging and thinking about it, it made sense to disconnect the I terminal. Made no sense as to having the tach to that.

It was giving power in the run position for the key.

After stepping away and disconnecting myself, I knew I needed a start signal from the key to the S, but with all the different wiring diagrams and color discrepancies I wasn’t sure which wire or how to trace it.

Then I found the TSM diagram and stared at it until I could understand it. Now I have single switched 12v to the dizzy, notch wire right now and a single wire to the S terminal. Being a solid green wire it matched the TSM diagram.

All good. Still don’t understand how I ended up wired the way I was. This makes sense. But to wire all of that and only have two out of place, I’m pretty impressed with myself.
 
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Now that I can crank and run, I’m starting to look at the vitals.

Oil pressure is strong on a cold engine, so we’ll see after it warms up.

The alternator gauge is jumping all over the place! Checked all grounds from battery to frame to block to alternator, all good and solid. And good continuity from regulator case to battery negative post. Voltage at the battery is measuring 14.5-14.75 fluctuating.

I have the Chrysler 80amp alternator with heavy gauge positive wire rated for 100+ amps running to battery+ side post of solenoid then the field wires running to the regulator with the red spliced to a switched 12v on the fuse panel.

Anyone have thoughts on that?
 
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It will hunt like that if the voltage is close to topped off, but it self regulates so that’s not an issue, you will get steady state charging when there’s a significant load on it like the coil firing at higher than idle rpm
 
Shreddinlettuce said:
It will hunt like that if the voltage is close to topped off, but it self regulates so that’s not an issue, you will get steady state charging when there’s a significant load on it like the coil firing at higher than idle rpm
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So the gauge is going to bounce like that when close to full?

Safe to say, ignore it for now and see what happens?
 
Shreddinlettuce said:
I would disable that gage and get a usb/ voltage gage

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Interested Ooo GIF by reactionseditor
 
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