[fouroheight68]

I had my car running yesterday, finished breaking in the cam and after 10 minutes of running, the motor went up and quit. I started by checking for spark, and sure enough there was none. I have a brand new gm hei distributor. Next, I tested for 12v to the distributor, and sure enough there was power. So i went on the carcraft website and used their hei diagnosis step by step and determined it was the coil by putting an ohm meter on it, and watching it jump drastically as i moved the power wire. I got a new replacement coil from kragen, put it all back together, still no spark. So i figured the only other thing it could be was the hei control module and bought a brand new one of those too, and hooked it all back up, still no spark. Visually, the cap looks good, and the rotor DOES turn as I crank the motor. What else can it be?? (bear in mind the rotor and cap are new)
thanks
-steve

[NXS]

About the only thing left is the pickup coil/inducer. You must pull the dizzy to replace it.

Check it with an ohm meter first!!

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Do you have a tach? Unhook it's wire and retest if you do.

==========================================

Yes 454! the rotor may well be bad!(even brand new)

[454me]

I saw this one time with a brand new rotor and cap. The spark was going through the rotor to ground at the shaft. That was fun to find.

[fouroheight68]

Ok, thanks for the help guys. I got it started today, by disconnecting the tach wire. When I disconnected that, it fired right up. However, once it fired it wouldnt turn off! We ended up throwing a rag over the carb to get it to shut off. I tested the wire to the tach with the key off, and there was no power.. hmm odd. So i plugged it back in and started it and it did it agian. (wouldnt turn off) So i tested the wire agian, and it had no power to it (ign off) I decided to plug the tach back in, and it fired, but wanted to die agian, and wouldnt start. Disconnected the tach, it fired up but wouldnt shut off.. what the heck is going on here!
thanks
-steve

also- the spot on the cap that says "tach" is supposed to go only to the tach right, and not a ground as well.. correct? What if you dont have a tach?

[67 Deuce 4 Me]

If your coil is in the cap you could have a bad rotor button. Simply pull off the cap leave the wires hooked up, make sure your wires ore clear of the rotor button. Take a test light and ground one end and hold the point of the test light about 3/4 inch from the coil button inside the cap ,have someone crank the engine and look for spark. If you have spark there you have a bad rotor button or your pinching a wire when you put the cap on> hope this helps.

[fouroheight68]

Hmm im not sure if I understand.. My problem now is that it will start, but wont shut off. The power to the distributor shuts off when i turn the key off though (I tested it after i stalled the car out) Any help?
thanks
-steve

[Matts99Sierra]

now im confused. if the power shuts off to the coil there shouldnt be any spark, therefore no ignition saying it shouldnt run. right? i am intriegued now....

[NXS]

The "tach" post on the distributor only goes to the Tach and nothing else. Especially the ground!

Do you have electric fans on the car? Depending on how they are wired they can cause run on after the key is turned off. Their inertia generates electricty that is put back into the wire harness.

Alternators can do this but they usually has a built in Diode that will allow electricity to flow only one way.

[fouroheight68]

No electric fans.. I cant figure this out! I run it, turn the key to off and it doesnt turn off. Finally starve the the motor and it stalls out, go to check the power wire and no power. What the heck?

[NXS]

What kind of accerories does the car have?

Can you test voltage to the wire while you turn the key on and off?

You are Sure the wire runs to the ignition switch?

[fouroheight68]

The only ascessories are water/oil/volt gauges, and a cd player. When you turn the key off, and put the tester on, no power (like it should be) when you turn the key on, 12 volts. When you plug in the distriubtor, and start it, it wont run with the tach wire plugged in. Unplug the tach, it runs. Go to turn it off and it wont turn off. Stall the motor, pull the power wire to the tach, test it, no power. Turn the key on power, turn it off no power. Start it agian, wont turn off.

[NXS]

Can you test the wire while it is plugged in and the car is running turning the key on and off?

If it stays hot the only thing left is the alternator.

Is this a hot rod?

Can you run a wire from the fuse box to either your ignition switch or a toggel switch and then to the distributor?

[fouroheight68]

i think the problem lies in the distributor, i dont know how but i think it does. Only because when i turn it on and off, the power works like it should. How would the alternator come into play here? the motor is in my 68 javelin, which is a 401 with a gm hei distributor (the housing is machined to fit). All internals are stock gm.

[NXS]

It's not the dizzy.


You need to run a fresh wire from the fuse box to the ignition switch to the distributors "Batt" terminal.

Or if this is not a restore car better yet would be a toggle switch.

[Siggy_Freud]

The coil power wire is still getting power after you turn off the key. That is the only way your problem is occuring. Where its getting the power from is the question. Mine does it from electric fans, but it shuts off after about 2 seconds.

Pull off your vbelt for the alternator and see if it does it still.