With the combination of time and heat some plastic electrical fittings begin to break down chemically releasing Aliphatic Amines - sometimes a fishy or ammonia smell and sometimes a green slime - most unpleasant.
Replace the electrical parts and clean up any connections - there is no other cure.
Search on here for - fishy smell - to find others with similar problems.
howtomendit.com for free repair help, information and advice.
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