Thats a heat or thermal shut down, usually caused by too low of resisitance in the primary ignition circuit. What coil are you using , resistance is = ????? Are you running a ballast with the coil + ????
If you have a 40001, 40011, or 40111 coil you need a ~1.5 ohm ballast resistor in the 12 v switched feed.
I just had 2 out of the box that would only run on 4 cylinders. This is for a Ford v8. rotate the exciter ring and the miss changed cylinders. put the points back in, car runs great. Never had a problem before. weird.
I forgot to ask if I can test by running the car long enough in the driveway.I don't wanna get stuck on the road again.
I started it with the old coil tonight and it ran for 17 minutes before we could here it missing and by 23 minutes it died. Then I put on a new coil and it started right up and ran for 1/2 hour smoothly before I shut it off. I don't know if I should expect this coil to crap out later or feel confident to take the car out. I will at least carry an extra. Is the lack of a ballast resistor causing the coil to fail?
The ballast resistor knocks down the voltage to the coil so the coil has a long life firing. It usually knocks voltage down to about 8 or so. You will want to keep the ballast resistor. The ignitor should be tied to the 12 volt side of the ballast resistor as the ignitor needs 12 volts. This is how I interpret the Pertronix instructions for a system with a ballast resistor.
Pertronix states that their 1.5 ohm coil does not require a ballast resistor. Here is a look at the current going trough the coil at 13.5.volts. If the coil continues to run hot I would add some ballast resistance for peace of mind. Is a very low value which could be a good compromise.
Ballast resistor installed,moved coil to firewall so it wouldn't get as hot. Runs good for now.Coil still get hot,is that normal?
Warm is ok, if it burns your hand I'd be worried, as Smokey says, it will stop making noise. If you have a voltmeter check the voltage at coil positive while idling.
They might have made them better 25 years ago. Like everyone else, production may have been moved to China.
Well,even though the coil says it's a 1.5 resistor,we figured out the right way to hook up the other resistor. It ran like shit. Apparently that cut too much voltage,so we by-passed it again. I guess I will carry a spare coil with me and see how far I get.
I think 1.8 was too high. If the coil runs hot try a much lower resistance resistor. Somewhere between .25 and .75 ohms.
56,.....Most 12 v. systems require the ballast resistor ; I believe it's possible for the lack of one to cause early coil failure. 4TTRUK
Well,I called Pertonix and the tech guy said the 1.5 built in is all you need and the coil could have been faulty.
That's "cool", problem solved. However, if you are still concerned about a hot coil or thermal shutdown here is a .2 ohm "Corvette" resistor. It will cool down that coil but only cut about .4 volts at higher RPM. It will mostly lower the voltage at lower RPM. The 1.8 Ohm resistor you tried cut the voltage down to about 6 way too low. Here is about what kind of heat you are generating with the Vette resistor. Cooler and you have a Vette ignition!!!
I had my coil go bad and instead of waiting for one to get here I called Pertronix. They told me that 1.2 ohm would be fine although it is at the bottom of their scale. That's when I went to NAPA and got an Accel Superstock . It's been in there for 4 years with no failure and I keep the Pertonix replacement just in case...
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