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Discussion Starter #1
The car starts fine and drives fine, but when in city traffic it will sputter, cough and shut down after 15-25 minutes. I thought is was fuel level related as it always happened just below 1/4 tank, but happened twice yesterday, 2nd time after a fill up. It will just turn over and over like it needs fuel. Finally after trying to flood and spraying a lot of carb cleaner down the throat, it starts and runs, drove 15 minutes home, (took about 15 minutes to re-start).

67 289, edelbrock performer intake, Holley 570 Avenger, mild cam, edelbrock fuel pump, power brakes, manual steering, C-4 (2300 stall), 9" 3.50 posi. Timing 14 BTDC, Vacuum 19-20, idle at 650-700. just changed plugs and were clean, mixture 1 3/4 out each side, fuel pressure was 6 psi, but then went to 0 and I drove it 15 minutes home, still 0 at home (gauge probably hot). After it died, I can see fuel squirt in the carb and the fuel bowls were adjusted to just leak when screw removed (both bowls), Engine temp gets to 200 to 205 in traffic.
 

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Discussion Starter #4

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Discussion Starter #5
Have you checked for spark immediately after the engine dies?
No, do you think it could be the coil? It's mounted to the head, possibly getting hot? The distributor is a new Pertronix (about 1 year old, no points) and the coil is Flamethrower about same age.
 

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Discussion Starter #6
I just checked the fuel line to the tank and it gets about 2-3 away from the exhaust pipe in one spot, but that's it. Not sure if that's close enough to cause vapor lock in the line.
 

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Yes. Definitely check for spark the next time this occurs.
At first my suspicion was the ignition module in the HEI, but since you have a Pertronix, I'm now leaning towards a failing coil.
But check spark first. That way you can positively eliminate fuel as the culprit, and focus your attention on diagnosing the ignition system.
 

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spray of ether will tell you if it's fuel or electrical mister bottle of water will be nice cause FIRE

gut is electrical something getting hot.....distributor cap?
 

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Discussion Starter #9
Bench checked MSD Blaster coil:
0.9 ohms across Pos & Neg
5180 ohms across Pos & Coil Terminal
5180 ohms across Neg & Coil Terminal
These readings were taken on a completely cold coil.
 

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I believe that the coil to negative should be 6000-15000 ohms.
Pertronix has a somewhat "mixed" reputation for reliability... Some seem to swear by them, and some who have been set afoot one too many times, swear AT them.
The coil going bad seems to be the most common problem. Some will argue that the oil filled coil needs to be mounted horizontally with the terminals at the 3 and 9 o'clock positions, to prevent them from failing prematurely. Others say that it makes no difference, horizontal or vertical.
Some folks have ditched the electronic ignition and gone back to using points and condenser.
Whichever ignition system is used, it is always prudent to carry along spare parts to replace the components that are most frequently prone to fail.
 

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Discussion Starter #12
Ok, I just talked to Pertronix Tech support.
He told me to unplug coil to Dist.
Connect Coil Neg to Ground
Set Meter to Volts
Put Red lead on Coil Pos
Put Black lead to Ground
Crank Engine for 5 seconds
Voltage over 9 volts is good and less is bad
My Reading is 6.8v, so I have a short or losing voltage somehow. Had some brake light issues and I guess it's a short. After the motor heats up, the available voltage drops below a running level. So problem identified, but not solved yet. I really hate looking for shorts, but at least it should be isolated to the brake circuit.
 

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No. You don't have a short. Not there anyway.
That wire going to the coil is a resistor wire. It drops the voltage to about 7 volts for the original points-type ignition.
You can just bypas that wire, and run a wire directly from the ignition switch to the coil to provide 12 volts.
Don't throw that resistor wire away though... You might need it again someday.
 

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Discussion Starter #16

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Discussion Starter #17
No. You don't have a short. Not there anyway.
That wire going to the coil is a resistor wire. It drops the voltage to about 7 volts for the original points-type ignition.
You can just bypas that wire, and run a wire directly from the ignition switch to the coil to provide 12 volts.
Don't throw that resistor wire away though... You might need it again someday.
I think that wire is directly from the ignition, I've had to replace some wires in the past. I don't have points, it's Hall effect.
Two wires on Positive side of the coil: Ignition and + Distributor.
Two wires on Negative side of coil: - Distributor and Tach.
Maybe I'm not understanding which wire you're referring to. The tech said I should be getting 9-10 volts. I have some sort of short or broken wire for the brakes.
 

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I would assume that someone replaced or bypassed the resistor wire during the course of installing the electronic ignition. It just seems odd that your voltage reading is about the same as would be expected with the resistor wire in place.
Just something to investigate during your diagnosis...
 

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Discussion Starter #19
I would assume that someone replaced or bypassed the resistor wire during the course of installing the electronic ignition. It just seems odd that your voltage reading is about the same as would be expected with the resistor wire in place.
Just something to investigate during your diagnosis...
Yeah it's kinda strange. When I got it had an old Pertronix distributor with an ignition box. There has been a lot of monkey business with this car.
What the tech said makes sense, but it looks more like I have an almost broken wire for the brake light. In the harness that goes into the light switch, it seems that you can move the harness and the brake light works. The wire is good all the way from that point to the trunk.
Maybe it's still the coil. I'm going to fix the wire and see what that does.
On a side note, I'm thinking about replacing my fuse box with one of the auxiliary fuse blocks, it's got 4 hot and 3 ignition hot with a 50 amp relay for $68. Those OEM fuse blocks are garbage.
 

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It certainly can't hurt to fix the known problems and upgrade the electrical system. A half-century old vehicle can probably use some TLC.

Keep us posted!
 
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