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Current cars include 1969 Mach 1 and 1970 Cougar XR7 convertible
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Discussion Starter · #1 ·
Well, I really did it this time...left the key in the "run" position with the engine not running for about an hour. The Pertronix Ignitor was totally fried leaving smelly residue on the rotor and Distributor cap. In addition, the wire on the back of the ignition switch that feeds the coil was also melted. I guess I'm lucky the whole car didn't go up in flames. Got a new pertronix, a new pertronix coil, a new distributor cap and rotor, and took the ignition switch apart and repaired the burnt wire. I'm getting 12V at the coil. Car still won't start. Per the troubleshooting instructions that came with the Pertronix I ran a wire from the battery to the red (+) lead of the ignitor and the damned thing still won't start. Thought maybe the ignition swith may also be fried, I pulled an old one (that worked when it was retired from srevice) and substituted it for the one in the car and still no luck. I'm going to get a set of points and condensor tomorrow to see if I can get it started. What a PITA
 

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Gone but never forgetten
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I've missed the previous posts, and want to play lazy. How did you hook up the new Pertronix? Is it in a stock distributor? Are there any other factors involved such as MSD boxes and such?

The reason for asking these, is that the 4 Pertronixes that I've installed, the only one that took more than 5 minutes was on my '66 with the MSD6-AL, which took about an hour.

Leaving the key in "on" with the engine not running, as you now know, is the worst thing thing you can do to any ignition system, electronic or points.
 

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Current cars include 1969 Mach 1 and 1970 Cougar XR7 convertible
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Discussion Starter · #3 ·
Stock distributor...no MSD. Red wire to + lead on Coil. black wire to - lead on coil. Very easy and fast but no luck...yet.
 

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What happens if I leave the key in the "ACC" position for an extended period of time? Will that hurt anything besides running down the battery?
 

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Since the key in the "on" position is the normal position when the car is running you shouldn"t have "fried" anything.

It's not necessarily good for the coil (bet it got hot) and the battery but the Pertronix shouldn't care.

Could something else be wrong here?
 

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Really!!!

I see their statement (and thanks) but I don't understand why. With the switch on you are applying the same 12V to the unit as when it's runnning (or slightly less due to a resistive wire or resistor)

I can see how it's not good for the coil but not the Pertronix. Maybe it's because without the rotor turning one of the hall effect sensor could be "on" and the transistor switch is "on" and the constant current heats it up?

Can anyone help me?
 

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The details are "beyond me"! /forums/images/icons/smile.gif

I know that it's a common problem to fry a Pertronix in this manner. On the Pertronix 2 unit, they promote that leaving the key on does NOT fry the unit, so they've figured something out..........
 

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Roadracer:
The only difference is that in one case, the engine and distributor are turning; the other case, they are not. When it is not turning, you can have constant high voltage (similar to points), which can overload the sensitive electronics, and fry them out.
 

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Midlife pretty much explained it. With the engine not running, and the switch on, the Pertronix is either detecting a magnet in the dist cam ring or not. Therefore, it's either putting out a ground to the coil or not, constantly. If it's applying a ground to the coil, there's now a good 8 amps or so of current flowing through the ignition switch, the wiring, the Pertonix, and then the coil. Constantly. With the engine running this 8 amps is pulsed, not constant, which is easier on everything involved. The 8 amps is from assuming a coil with a primary resistance of 1.5 ohms, at 12 volts. The Pertronix is now doing what's called "sinking" 8 amps of current, which is quite a bunch for such a tiny device.
 
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