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Old 10-29-2012, 10:31 AM
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Originally Posted by Hammerstein View Post
So I just got done rewiring a 76 corvette, and everything has gone smoothly until I went to start it. Now mind you; the car ran fine when I parked it at the beginning of summer and the only reason it was being rewired is because I had rewired it before when I was still learning and had a lot of poor craftsmanship. I used a generic painless universal harness. When I turn the key the engine cranks just fine, but i don't appear to have any spark. I checked the voltage on the +coil wire and it reads 12 V. I have the ground on the HEI going to the choke's ground on the carburetor (though I did also try a different ground when I was troubleshooting). From what I can see, everything is working the way it should but I can't see a spark either with the plug or with a socket shoved in the wire boot. So far I have swapped out the ignition module, cap, and coil but nothing has got it to fire. I've now become more certain that it must be my wiring, but I have no idea where to look next. An HEI only has 3 wires going to it correct? (tach, coil, ground?) I even checked the +coil wire's voltage as I turned the key to "start" to see if the voltage was cutting out of something, but no dice. Someone please help!

Hammer S
I'm not following you on the choke ground wire. The choke heater is grounded through the choke housing to the carb body, intake, cylinder head, etc. on through to the battery, no ground wire needed. The only wire required at the choke itself is a 12 v current carrying wire.

The ground on the distributor is connected to the coil on one end and the body of the distributor on the other. The rest of the ground pathway is through the dist. body through the clamp and bolt into the engine block, etc. on to the battery eventually.

As for the power supply wire having a splice in it (if that's the case), I would caution you against using the coil power wire to run anything else. The HEI needs full battery current to work at its best.

Be sure there is a male terminal in the center position in the coil cover that mates w/the female 3-wire connecter/pigtail that's attached to the distributor. That's the ground for the coil. The way the ground is made, it can be accidentally left off. It will be either a wire or solid metal conductor running to one of the coil holddown screws. If it's left off, the coil will not be grounded.

Last edited by cobalt327; 10-29-2012 at 10:44 AM.
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