HEI Distributor - Do I need to replace any of these parts?

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AuroraGirl

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I have a new cap. It's the coil that has a crack. Looking at the photos I posted, it didn't show. The outside frame of it has a crack
 

AuroraGirl

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I found more caps and 3 distributors. 2 more as well, but they are both pre-HEI

So that means I have a post draft tube, post generator, pre-HEI sbc. that would be 69 to 73, yes?

Anywho, the two on the left i imagine are from squares, the left most one being from my 78 with a 400.

This also tells me I have 2 coils which are damn near pristine, at least appearance wise. I dont plan on dropping these into mine, but do you think maybe I could use the 400 distributor and clean it and use it to diagnose my dads 400 issues? His is a 75 instead of a 78, both were options similar. Im meaning the mechanical advance. Otherwise i can try cleaning his, he said its not firing right and i was gonna confirm firing order and base timing

The distributor on the right is from a sedan, and I think the weights are smaller because of the expected load that it would be under? Anyone who can say otherwise?

On the coils, is there a difference in years for the ground wire that goes in the center of some, but is a metal tab on others? Design choice, different function?
Of the pristine looking coils, I think im going to use the center one of the 3 distributors for its coil. has nice obvious grounds, clean, and not sketchy.
 

AuroraGirl

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Im replacing my ground cable to the core support. As that caused me to melt that wire a bit. Bigger gauge wire isnt bad methinks?
Then maybe I can try starting it after that, without melting. I Would like to replace to the bracket, too, but stores will be closed tomorrow and i might not have a new one htat long. I can send it till then

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AuroraGirl

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I cleaned up the distributor for the 400 just to see how it's done and maybe use it for my dad. World of difference how well they kick out
 
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MrMarty51

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I mean, I researched and to my understanding sticky weights could cause my random holding at 1000 or more RPM that dont like to kick down? What do I lube it with?
I always used the very lightest lithium grease I could find, and not a whole lot of it. On the weights base, the portion with the posts, there will be a couple of raised up portions that the weights rest and ride on, give those a light coating too.
The advance plate can also bind on the shaft, that requires a complete tear down, before removing the roll pin, be sure to note which direction the dimple is in compared to the pointer on the rotor. Also, after shaft is removed, very carefully pry out the grease retainer that is under the shaft, a clear plastic plate that keeps oil from entering the distributor. after it is removed, pry and flush all of that old hardened grease out of the slots and crevices, clean it real good and fill the cavities with regular engine assembly lube, white lithium. While the advance plate is removed, clean it up very good and lube it too with some real nice thin grease and be sure it rotates freely on the distributor shaft.
When disassembling, lay out the components, left to right and reassemble in the reverse order.
Your distributor will function like new again and, it will thank You. LOL
 

Turbo4whl

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@AuroraGirl Hey Taylor, the small ground wire to the core support most likely overheated because the engine starter was grounding through it. The main ground cable most likely has very high resistance. Maybe loose connection to the engine block, but that ground cable looks bad.

No other electrical accessory would require the amount of amperage to heat a ground to the core. Starter voltage found it's path through that smaller wire.


Added Note: An electric snow plow lift could also draw enough amperage to heat that core support ground.
 
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AuroraGirl

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@AuroraGirl Hey Taylor, the small ground wire to the core support most likely overheated because the engine starter was grounding through it. The main ground cable most likely has very high resistance. Maybe loose connection to the engine block, but that ground cable looks bad.

No other electrical accessory would require the amount of amperage to heat a ground to the core. Starter voltage found it's path through that smaller wire.
I had figured such, I DO have a 51 inch lug to lug 2 gauge cable to ground the battery and alternator bracket. But are you thinking the one by firewall? I plan to clean up that ground.
 

Turbo4whl

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Same problem, if the main battery ground fails, the starter needed more amperage. Path may have been from the small ground to the firewall, through all the sheet metal to the core support, then the core support ground to the battery.
 

AuroraGirl

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Same problem, if the main battery ground fails, the starter needed more amperage. Path may have been from the small ground to the firewall, through all the sheet metal to the core support, then the core support ground to the battery.
The ground strap on firewall is actually pretty cruddy and almost loose. It's getting cleaned.

Also, did I commit a sin by using a threadsert instead of tapping the frame or using a nut? I used a threadsert and cleaned the hole area.
 

AuroraGirl

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@AuroraGirl Hey Taylor, the small ground wire to the core support most likely overheated because the engine starter was grounding through it. The main ground cable most likely has very high resistance. Maybe loose connection to the engine block, but that ground cable looks bad.

No other electrical accessory would require the amount of amperage to heat a ground to the core. Starter voltage found it's path through that smaller wire.


Added Note: An electric snow plow lift could also draw enough amperage to heat that core support ground.
That's grounded elsewhere but it's not in use atm. Unhooked.
 

AuroraGirl

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Also, I didnt realize distributors were aluminum. Mine coulda fooled me when I had it out last summer. I polished this one up so it wasnt full of junk. just needs an o ring.

Also, im gonna feel stupid asking.. where does the o ring go?

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AuroraGirl

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Firewall ground. Was a self tapping screw much too small(or eyelet of ground strap too large) and it also stripped its own threads on the thin sheet metal.

I changed it. After tidying up these grounds, the truck turns over FAST. Holy cow! And I didnt even make it perfect et. BUt it FLYS. Cant get it to start, was gonna check if my rotor was on 180 degrees off

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MrMarty51

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Also, I didnt realize distributors were aluminum. Mine coulda fooled me when I had it out last summer. I polished this one up so it wasnt full of junk. just needs an o ring.

Also, im gonna feel stupid asking.. where does the o ring go?

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Just a flat round gasket on those.
 

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The pins and weights are worn out, get a new one.plenty of cheap performance HEI’s out there.
 

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