9-N coils

- the original-equipment ignition resistor (mounted on the front left side of the dash) is missing or has been bypassed in order to get a "hotter" spark, or

- someone - maybe you - is leaving the ignition on when the engine is not running.

If unsure as to resistor condition, attach a volmeter between ground and the terminal stud on top of the coil. With ignition on and all 4 plug wires disconnected (so it doesn't start) observe the voltmeter reading. It will be either about 6.2 volts, or about 3.5 volts. If it is 6.2 volts, "nudge" the motor over with the starter button. The voltage should cycle between those two values as the motor turns over. If it does not, the ignition resistor is non-functional or missing. This causes excessive voltage at the coil, with the result you have found. Replace with an original-equipment styler resistor (about $8) or a "universal" voltage reducing resistor (about $4).

HTH

llater,

llamas