By the age of 18, John had become an apprentice painter in Leven. He gained experience in Dumbarton and in London before returning home and setting up business as a house painter. As his business in Lundin Links grew (at a time when the village was greatly expanding), he moved to 'Wellfield' on the corner of Mill Wynd and Largo Road and became increasingly involved in community life.
In the early 1920s John Adam became a member of Largo Parish Council and was elected Chair in 1924. He held the role of Chair for 6 of the 12 years that he served on the Council, and remained a member until his death in 1932. He was also involved in the Fife Education Committee and on the day of his sudden death on 26 May 1932, John was described as a "well-known Fife County Councillor and Educationalist" with a "fine record of public service" by the Evening Telegraph. In fact, he had just left an education sub-committee meeting and was walking along Kirkcaldy High Street when he collapsed and died from a heart attack, age 59. He was also a long-time member of Lundin Golf Club and a keen curler, since the inception of the Lundin Club in 1906. John Adam had been predeceased by his wife Christina but was survived by their children.