On GM HEI in the late 70's to the 90's rotors frequently burned due to bad plug wires...different manufacturer but same principle. The rotor would burn a hole in the plastic and short circuit the spark to ground through via the distributor shaft. The fix was cap, rotor and wires. A telltale was a buildup of black powder/dust under the rotor.


Good luck and please let us know what you find.

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"Rudeness is a weak man's imitation of strength" - Eric Hoffer