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429 thunder jet sitting on engine stand, wire from battery to positive side of coil, pointless pertronix, coil to hot to touch why ?
 

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Unless the coil is stock and does not have a ballast resistor built-in like aftermarket coils, there will be nothing to limit the current through the coil except the resistance of the coil wiring itself and it will get hot. Get a 1.5 ohm ballast resistor at the auto parts store and put it inline with the positive side of the coil if it is a stock coil.
 

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Discussion Starter · #5 ·
Unless the coil is stock and does not have a ballast resistor built-in like aftermarket coils, there will be nothing to limit the current through the coil except the resistance of the coil wiring itself and it will get hot. Get a 1.5 ohm ballast resistor at the auto parts store and put it inline with the positive side of the coil if it is a stock coil.
it is not a stock coil
 

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Putting power to the coil with the engine NOT running saturates the coil and causes it to overheat.

Short answer.... Don't do that. You will burn out the coil.
i left the battery hooked up all nite next morning hotter than hell
 

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429 thunder jet sitting on engine stand, wire from battery to positive side of coil, pointless pertronix, coil to hot to touch why ?
You have it backward in-theory. The question is why are you powering the ignition system when not running the engine? Fortunately, there should be no damage to your parts (crossed fingers), as that version of module has current limiters in it.

No, the 1281 is not an Ignitor I, but an Ignitor II. Like points, if you leave it powered and it's at a crank/distributor position to dwell (charge) the ignition coil, it will, if powered. However, the PII version has extra circuits the cheaper PI doesn't, so it can perform similar to HEI spark power.

To get this energy, a current-limiting ballast resistor is not used. Instead the module limits the power when it exceeds internal limits. This is the advantage of the PII - better spark with safety features. If you leave it KOEO (key on, engine off), it will limit current to save the coil. The coil will get really hot, but (hopefully) won't burn-up.

To get the extra spark energy, it limits the current to a maximum value, so you don't destroy your coil (in normal operation), even without a ballast resistor (see the directions). You can use a ballast resistor, but then you are limiting spark power to the same level as normal points or the PI.

I don't know how many ways I can say this — it is working properly. Remove power (switch it off) if you're not running it.;)
 

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ahhhh - thank you PSIG. i got my model numbers mixed up, and thought we were talking about an Ignitor I.

edit -
wait...i think the 1281 is an Ignitor I?
the Ignitor II is # 91281.
 

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Pretty sure a Pertronix 1281 is an Ignitor I (well, I think it's just called "Ignitor" by Pertronix) and the Ignitor II is 91281.

Pat
 

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You are right. I went to a reseller site for the instructions (which were Ignitor II), not PerTronix directly. My apologies. :oops: The coil and module were lucky to survive that type of punishment.

However, that wasn't the primary point. The first and primary point is still valid that the issue only appeared due to leaving the ignition power ON when the engine was not running. All night. With or without a resistor, the coil would be cooking. The lesson is still to turn ignition power OFF when the engine is not running.

Akin to "I dropped my beer bottle from the roof and it broke. Why?", the primary issue is not rooted in PerTronix, coil type, resistor, or other. Minimally, a dead battery would result and is simply not a condition you should subject your vehicle or parts to in any case. This should be obvious, IMO.

Thanks for pointing-out my mistake. Good info is always the goal, which it was, but for the wrong part number. (y) Looking for a silver lining; hopefully some readers learned some differences and benefits between the versions.
 

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Looking for a silver lining; hopefully some readers learned some differences and benefits between the versions.
PSIG, you may be reading my mind- i was hoping this would turn into a conversation about the differences between the Ignitors.

here's the rough way I think about them - please feel free to give it more context:

Ignitor I - an electronic replacement for points
Ignitor II - equivalent to GM's HEI
Ignitor III - equivalent to MSD's box with the rev limiter
 

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Ignitor I - an electronic replacement for points (retaining original coil type and coil resistor)
Ignitor II - equivalent to GM's HEI (if used with proper new low-ohm coil type, e.g., 45011, and no coil resistor)
Ignitor III - equivalent to MSD's box with the rev limiter (if used with proper new coil type, e.g., 60103 or 44011, and no coil resistor)
I'd say that's a good snapshot, and I've added some qualifications to your outline for clarity. Thanks! :cool:
 
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