Build Up On Distributor Crown

Has anyone ever seen this before and if so what casues it and how should I go about cleaning it?

After starting up my Plymouth for the 1st time after sitting all winter she did not what to run and missed real bad. I had just did an oil and filter change and was taking her for state inspection. I decided to change plugs and thought since the distributor is an MDS and they use 3 different rotors I better double check to see what style mine was and this is what I fould after I remover the distributor cap.

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Author: admin