Mr. and Mrs. James S. Wey of Needham, Mass., have announced the engagement of their daughter, Susan M. Wey, to William Colyer Crum, son of Prof. and Mrs. Colyer Crum of Weston, Mass., and Sunapee, N.H.

A September wedding is planned in Needham. Miss Wey, an engineer at Honeywell Electro-Optics Operations in Lexington, Mass., was graduated cum laude from Wellesley College and next month expects to receive an M.S. degree in electrical engineering from Northeastern University.

Her father is with the trust department of Hale & Dorr in Boston.

Mr. Crum, who is a magna cum laude graduate of Harvard College, is a third-year student in the joint J.D.-M.B.A. degree program at the Harvard Law School and the Harvard Graduate School of Business Administration. His father is James R. Williston Professor of Investment Management at the Harvard Graduate School of Business Administration.

Mary Ellen Maxwell, daughter of Mrs. James A. Maxwell Worcester, Massachusetts, and the late Professor Maxwell, was married yesterday on Hakan Nicolaus Lonaeus of Washington, son Gunnar Lonaeus, Japan Ambassador to Sweden, and Ms. Lonaeus of Skarkind, Sweden and Tokyo. Canon Lorne D. Coyle, the ceremony Trinity Episcopal Church in Newport, RI

Mary Catherine Hogan was maid of honor and Liv Tralla, husband of the niece, was a companion.

Lonaeus Erland served as best man The bride, who retain their name, studied at Smith College and studied international finance at New York University School of Business Administration. His father was a professor emeritus of economics at the teaching of Clark University.

Mr. Lonaeus, a financial analyst with the World Bank in Washington, served as an officer high level in the budget of the Ministry of Finance, Stockholm. He earned a Master’s Degree in Business Administration from the University of Lund, Sweden and was a Visiting Research Fellow at the Harvard Graduate School of Business Administration. His father served as Consul General to New York from 1970 to 1975.

LEAD: Lauri Ann Livesey, a daughter of Mr. And Mrs. James William Livesey of Chappaqua, NY, here, he was married to Michael James Sanduski, a son of Mr. And Mrs. Albert James Sanduski Omaha. Monsignor Robert J. Skelly, the ceremony of St. John and St. Mary’s, the Roman Catholic church.

Lauri Ann Livesey, a daughter of Mr. And Mrs. James William Livesey of Chappaqua, NY, here, he was married to Michael James Sanduski, a son of Mr. And Mrs. Albert James Sanduski Omaha. Monsignor Robert J. Skelly, the ceremony of St. John and St. Mary’s, the Roman Catholic church.

Sanduski woman who has kept his professional name, is a financial analyst for IBM Europe in Paris. She holds a bachelor at Dartmouth College and an MBA from the Amos Tuck School of Business Administration at Dartmouth. His father is the head of the art for the New Rochelle, NY, public schools. His mother, Eleanore Livesey, is the supervisor of mathematics at the Woodlands High School in Hartsdale, NY

Mr. Sanduski is studying an MBA from the Harvard Graduate School of Business Administration, he is on leave from his job as a financial analyst for General Electric in New York. He received a degree from the University of Nebraska and studied two years at Nanzan University in Nagoya, Japan. His mother, Constance Sanduski Reynolds, is an administrative assistant in the communication at AT & T. In Omaha, where his father was a high wage specialist practices.