I know of four different Jehudi Ashmuns.The one who looks possible for your query d. 11 Feb 1833 at the age of 67, so was b. abt 1765. I have no marriage information, and I don't know who his parents were, but I suspect that he was the brother of Samuel Ashmun (b. 1764) of Champlain, NY, since Samuel was the progenitor of three younger Jehudis -- including the "famous" Jehudi who went to Liberia and the Jehudi you found in Michigan and a Jehudi who went to Waupaca County, Wisconsin.
Here's what I know about him: "An Act to Incorporate the Maine Charity School in the county of Hancock.Approved Feb. 25, 1814.To establish a literary seminary." "The seminary was opened in October, 1816.The first year it had one professor, Reverend Jehudi Ashmun." "The same year the old professors or teachers resigned: Reverend Professor Ashmun went to Deer Isle, 1819 to 1831.He died at Worcester, February 11, 1833, aged sixty-seven."I don't know which Worcester this would be.