No spark, need help......

[Excaliber]

Very few cars, these days DO include a ballast resistor. It's function is handled by an electronic type ignition control module. But what your doing is like an old school point and condensor type wiring, no electronics, just wired straight to the battery with the negative wire acting, as it were, "the points". A mechanical switch that makes or breaks the current, with a condensor that helps to limit arcing across the point contacts which would lead to burned and pitted contacts.

SOME coil's have an INTERNAL ballast resistor, some require an external one. Often, with todays modern coils designed to work with electronics, they do not have nor require an INTERNAL resistor. A resister can be purchased from any neighborhood parts store. They all serve the same basic function, reducing the voltage from 12 to 6 or 7 volts. It really doesn't matter what vehicle you have, if it came with points, it had a resistor OR (like GM) a resistor WIRE included in the wiring harness.

12 volts to a coil without a resistor will burn up the primary wiring inside the coil, you will not see the damage.

[Murky781]

Adding to this thread because I have NO SPARK. 69' 428, MSD-6AL, replaced coil, voltage reg. ignition switch. Did the paper clip test on the MSD, it was good. Car turns over quickly, but will not fire. Screwdriver in coil wire doesn't spark. Dist. is turning, rotor looks good, not carbon trails in cap. Battery fully charged and grounds checked.
Car ran great, then was hard to start, (20 secs. cranking) turned it off, then 40 sec cranking. one last start of close to a minute cranking, got it home and it will not spark now. I'm open to help, dash is out and i have power to ign. switch with power on and cranking. Beautiful day and I'm stuck!!! thanks guys
It's an ERA if that makes any difference

[davecobra]

I had a msd pickup coil in the dist go bad and that is how it acted, paper clip test said box was okay, but the pickup coil in the dist failed, replaced it and it worked. For the record it started to act up several days earlier, would be very hard to start, had to crank and crank and finally it would start, then it left me stranded at the store, no spark, had to tow it home, took a week for me to find the problem. Hope that helps.
David

[patrickt]

Originally Posted by Murky781

Adding to this thread because I have NO SPARK. 69' 428, MSD-6AL, replaced coil, voltage reg. ignition switch. Did the paper clip test on the MSD, it was good.

When you do this, what is the result? Do you get a spark to ground?

1. Make sure the ignition switch is in the “Off” position.
2. Remove the coil wire from the distributor cap and set the terminal approximately 1/2" from ground.
3. Disconnect the MSD magnetic pickup wires from the distributor.
4. Turn the ignition to the On position. Do not crank the engine.
5. With a small jumper wire, short the MSD’s Green and Violet magnetic pickup wires together several times. Each time you break this short, a spark should jump from the coil wire to ground.

[Murky781]

To Dave... that's what went on with this. Haven't checked that yet..any easy way to do it? Patrick..I did that and I get a good spark to ground. I'm just lost as where to go. No spark from coil wire to ground by cranking.
thanks

[patrickt]

Originally Posted by Murky781

Patrick..I did that and I get a good spark to ground. I'm just lost as where to go. No spark from coil wire to ground by cranking.
thanks

The the next step is to keep everything exactly the same and plug the magnetic pickup back in and crank it. If you see no spark going to ground while cranking then it is the magnetic pickup.

[patrickt]

BTW, the gap between the reluctor wheel and the magnetic pickup should be about .028 to .030 of an inch. If it's really out of whack, that can keep it from sending the signal to trigger the spark.

[Murky781]

Thank you Patrickt.. No spark after replug. I'm guessing the magnetic pickup is that little blue thingy under my rotor? Hard to get a feeler gauge in there, but it looks like nothings moved way out of whack. Now where does one get a mag. pickup? MSG? Frustrated, but appreciate the help.