No Spark

[pshepard327ci]

My 70 240z with unilite dist. and promaster coil is not getting spark. It hasnt ran since the L24 was reinstalled. I do have the ballast resistor and just ordered a new one online to see if that was the problem(much smaller than one that i had). I tested my module and it was bad, so ordered a new one of those thinking that was the problem. After hooking up per instructions, when cranking no spark and the ballast resistor begins to smoke and is pretty hot. I have it grounded correctly and wired 12v one side and then to + coil other side.

Would a bad coil cause the ballast resistor to get prety hot and smoke... either no one knows or I must be the first with this problem. Some advice would be great, and much appreciated.

[240ZX]

Have you checked and rechecked your wiring? Its obvious you have power to the ballast resistor.

[Blue Meanie]

Check the rotor and the points.

[EScanlon]

You have a "module" AND you have the resistor? Aren't you asking for problems? The resistor was in place to reduce the voltage to the points while the engine was running (it got bypassed in Start mode). Keeping the resistor after changing the dizzy to electronic mode is simply going to starve the module (IF it runs at all).

2¢

E

[pshepard327ci]

I just rewired the way that Mallory showed and a diagram i found on here or zcar.com showed. It was hooked up similar to this when i purchased the car several years ago and it ran then. If i need to take the resistor off thats no problem but there must be something else going on to cause it to begin to get so hot. What is the most basic way to hook the coil up for testing purposes, +12 to coil +?

[EScanlon]

Don't know where you would have seen the resistor left in the circuit with an electronic module, but DO get rid of it.

Since it is IN the path from Ignition Switch to Coil (with a detour to the Tach), you can't just disconnect it. You basically connect both wires going to it, and effectively remove it.

However, with the problems you are mentioning, I'm wondering if you don't have something else reversed.

The simplest connection is +12v to the + side of the coil (this bypasses the ignition switch and the tach, and as long as you didn't disconnect the rest of the wiring harness you should still be able to turn the key and use the starter. You can also plug in a remote starter switch.

Before you start wiring, I would double check the wiring to the coil and the electronic module. It just seems extremely spooky that the resistor should smoke like that....then again a brand new resistor with a thin coating of oil WOULD burn that off once the key was in the Run position. Remember the resistor's job is to reduce the 12v down to 6 or so. The reason the resistor is basically a coiled wire is so that it can dissipate the energy absorbed as HEAT.

HTH

E

[mcguire240z]

hey man, i had almost the exact same problem with the exception that I would get one spark after I stopped turning the engine over. I just purchased a pertronix ignitor ignition with matching coil and removed the ballast resistor, now it starts and runs fine. I too had the ballast resistor on my car with a crane cams xr700 module for more than a few years and ran fine, but it ended up not running. but yes my ballast resistor smoked as well. If I were you I would purchase the pertronix ignitor and hook it up in about 10 minutes. My car runs like a champ now. Hope this helps.

[pshepard327ci]

Thanks mcguire240z, i will look into how much that cost, i unfortunatly just purchased the Mallory module for $90, i will look and see if it is returnable, hasnt run yet so would think it would be. Do you know off the top of your head what the part number for the ignitor and coil is?

[sblake01]

IIRC, the Pertronix Igniter for a 70-73 Z is CDM61 for the single point dist. And the coil is 511.