How much does an Assoc. Professor - Mechanical Engineering make in Maine? The average Assoc. Professor - Mechanical Engineering salary in Maine is $91,719 as of November 25, 2019, but the range typically falls between $78,797 and $117,007. Salary ranges can vary widely depending on the city and many other important factors, including education, certifications, additional skills, the number of years you have spent in your profession.