1968 weird "stalls with headlights on" problem

[robert campbell]

Tom,
I think that a 12 volt source for the Pertronix will fix your problem. I bypassed my resistor wire when I installed mine. So the stock wire at the coil had 12 volts. You should be able to prove this very quickly. Of note, there is a "12 volt" source at the 4 wire block that goes down to you automatic and/or backup switch. Neil or Steve came up with a novel way to "add" a connection point there without cutting a wire. This will allow you to run a separate wire down to the coil from there.

Rob

 

[franklinair]

What's the latest status??

Neil

 

[robert campbell]

me to!!
Did you FIX IT... Love that FIX IT guy on Saturday Night Live!

Rob

 

[tomcwarren]

Sorry, guys. Been busy supervising a bathroom/kitchen remodel here @ home.

I (somehow) blew up the Ignitor in my distributor trying to get a full 12V to it (ran great for awhile w/HL, A/C and Lucas all on, then wouldn't fire up again). Got a new one (wanted an Ignitor II since it's more robust, but the shop didn't have any and I had to get it running for the show @ Berge Ford on Saturday).

Fired up after some coaxing, and ran fine up to the show and back (at night, w/headlights, including cruise down Main Street in Mesa :grin. Still hooked up in the 'incorrect' fashion (red wire to coil + terminal), but, hey, it's working.

Either the newer version of the Ignitor is less sensitive to voltage drops, or it's seeing 8+ volts because I removed the electric choke wire that was piggy-backed off of the selonoid 'I' terminal, or I just got lucky. But until it gets really cold again here, I'm leaving it as-is. If it ain't broke, don't fix it. :embarass:

Thanks for all the help - this site/forum is a fantastic resource!

Tom

 

[rvrtrash]

I've been gone for a bit and trying to catch up. Keep in mind that it's not just voltage that you want to look for, but power, which is a combination of voltage and amperage (V times A=P). I'm not familiar with the Pertronix, but here's something to think about. Your module needs a certain amount of power to work correctly. If you drop the voltage from 12V to 9V, you need more amperage to make it up. If you are running the electric choke off the same wire as your ignition module, the electric choke is probably getting most of the power, because it's a heating coil (Lower input resistance, so gets most of the amperage). At low rpm when your alternator isn't putting out much and you have a heavy load on the system, the power available at your ignition module is probably dropping below the minimum it needs to keep operating. I know this can all be confusing, but in a nutshell, you need to put the electric choke on it's own line.

Steve

 

[robert campbell]

Tom,
I burned up 2 Petronix original ignitors when I first converted. The Pertonix people highly recommend using their coil. They are more compatible to the ignitor. I was running a Mallory coil. Burned 2 of them up. Carried my points and condensor with me to save myself. My ignitor was extremely hot to the touch when it burned up. Motor was still somewhat cold and it was obvious.

Thank God Sumitt Racing took pity on me. Bought the Pertonix coil and never had another problem.

If you get into the specs, the resistance in the coil windings can vary from brand to brand. I am way over my head saying such electrical terms, but it fixed my problem.

Welcome back Steve!!! Spring skiing??

Rob

 

[rvrtrash]

Welcome back Steve!!! Spring skiing??

Rob

I wish. I'm having problems with the discs in my neck again and have been going to doctors or physical therapy every night. The little time I do have has been spent trying to get the brake system on my Tiger rebuilt before I have to go to Oklahoma in a week. I guess I really need to get on that now 'cause it looks like Arlie is coming through here again in May and he was really disappointed I was rebuilding the rear end and he couldn't drive it last time.

Steve

 

[tomcwarren]

Thanks, Steve. I remember something from my EE classes (before I got into lasers & optical gyros, and now CS [system BIOS/firmware]), but don't often have the chance to put it to use.

I'll run a separate 12V line to the carb's choke, and find a Flame Thrower coil as per Rob's excellent suggestion. I did pick up a set of points & condenser and keep it in my trunk toolbox just in case the second Ignitor quits on me. Let's hope I remember how to gap a set of points! :wink:

Thanks one last time for all the great help, guys!

Tom