HEI distrib problem under load

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Goldie Driver

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also this is a dumb seeming comment, but KISS is always watching and present..

how are your plugs and wires?


Ive had a bad wire that i presume was internally too resistive from factory and when i Put it on, I had a cutout, miss, but more from the lack of participation of a cylinder rather than improper timing of the combustion, and found my wire , which was new, worked fine at idle but if i gave the throttle some go, it would arc out of the middle of the wire onto my engine hoist hook

ignore the random paint doodles on the engine
earlier this year i was marking fasteners that I suspected were loosening from vibration and the markers and the atmospheric conditions made a perfect scenario in which i think the paint fumes made me a little high because i ended up doing that for an hour and eventually I was like "what the **** am i doing" and got some air. It was a weird day.

ANyway, see the hook, my wire was closer to it and defective, it like melted the wire sleeve at the spot too, weird. See the coil end? You have a cap of course, but the idea is the same. The nub the wire is on needs to be air tight, secured tightly to the nub on the tower, and also clean of corrosion. any corrosion is resistance, any arcing or carbon tracking(ionization from high voltage spark jumping the gap in the closed space, etching carbon into the metal or just slowly zapping away metal) is resistance, any gap is energy spent to cross the small air space instead of conducting through the wire and cap, and that energy is less vroom vroom from engine and it can be a situation where load/rpm it gets worse, but handles idle ok. improperly pulling wires(recommend the pliers) is great at separating the end on the wire so it becomes loose fitting. Use some dieletric grease to seal out 1) moisture 2) air. you want there to be no place for air since its displaced by the grease. which also keeps it easier to remove especially on plugs that are smooth on the porcelain. the ribs are common on our trucks, which btoh can be a bitch to pull off. Also then finally, the plug.

A bad plug doesnt let the zap zap make the vroom vroom.

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LOL - Homer Simpson voice :

Can ya dumb it down a little , Doc ? :anitoof:

A bad plug doesnt let the zap zap make the vroom vroom.
 

Gene King

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Got the top off and attached a couple photos. The inside of the rotor is full of this red powder and a bit of metal shavings.
On my advance weights I've got a spot rubbed shiny at the 7 o'clock position.
Any idea what's goin' on here?


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AuroraGirl

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Got the top off and attached a couple photos. The inside of the rotor is full of this red powder and a bit of metal shavings.
On my advance weights I've got a spot rubbed shiny at the 7 o'clock position.
Any idea what's goin' on here?


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I’m not sure. Do they move freeely amd return nice,
If you kick them out and play with them. Consistent feel. The rust otherwise may nit be a huge worry.
 

AuroraGirl

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Thanks a lot AuroraGirl I'm about to go out and monkey with it, will reference those photos.
The problem is definitely more severe than just running on 7 cylinders from a bad plug or wire.
It's erratic but sometimes it loses ignition completely for a second, then gas will build up in the exhaust and make a hell of an explosion sound when it does fire again.
I can't get it to do it in the driveway though.
Anyway I'm about to take the top off that distrib and see what I can see
A vast change in fueling could do that too. Fuel line ok?
How’s your coil look
 

Gene King

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Yeah the weights move around okay. Nothing looks burned or broken visually with the coil.
I looked fuel up and down yesterday, pressure and flow tested pump, put on a different carb. Engine holds steady 20 pounds of vacuum too
 

Gene King

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This is an Accel aftermarket distributor, any idea if I can put a standard GM coil and ignition module in it?
 

AuroraGirl

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This is an Accel aftermarket distributor, any idea if I can put a standard GM coil and ignition module in it?
I don’t see why it wouldn’t work just would lack the cosmetics of accel but I’ve heard of poor qc on their distributors. Like, you get a great one or it blows and it’s too frequently blows
 

Gene King

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I don’t see why it wouldn’t work just would lack the cosmetics of accel but I’ve heard of poor qc on their distributors. Like, you get a great one or it blows and it’s too frequently blows

May try swapping those soon. Not sure what else to try
 
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AuroraGirl

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May try swapping those soon. Not sure what else to try
All the other things mentioned :( I’m cereal, check those wires. Visually and if adventurous with a multi meter. Or. Here how about this. Are you able to replicate the issue at idle or low speed
 

Gene King

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I figured out the problem. The hot wire to the distributor was arcing inside the connector when the motor would try to turn on the motor mounts under load.

Thanks for your guys' help
 

Gene King

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AuroraGirl

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New connector, clean the coil pin by taking it out, then a lil dielectric grease on the connector and firmly connect to tab. Fix for another 40
 

Gene King

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New connector, clean the coil pin by taking it out, then a lil dielectric grease on the connector and firmly connect to tab. Fix for another 40

Heh I bamboozled you guys a little bit, wasn't actually my square body you were helpin' me fix, attached a photo.

I cut the pig tail off a parts van and butt connector'd it on, should be good.

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AuroraGirl

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The cool part is this all could have equally applied to a 4.3 v6, a 260 Oldsmobile, a 350 Buick, a 400 sbc, a 396 bbc, a 250 i6, an GM style hei distributor for a Ford 289, and your mom I mean your Camaro :)
 

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