Alexander James Hill II, 86, a retired mechanical engineer who was involved in research and development of earth-moving and heavy construction equipment during a career with the Army Corps of Engineers, died of pneumonia June 7 at Suburban Hospital.

Before his retirement in 1975, he spent 35 years with the Corps of Engineers, at one point serving as branch chief in the Ground Mobility Division.

During World War II and the Korean War, he worked on the development of special construction equipment for military use. He also served as a civilian defense warden and a registration organizer for the Silver Spring area, where he lived for more than 40 years.

Mr. Hill, a Bethesda resident since the early 1990s, was a native of Judith Gap, Mont., and a graduate of Montana State University. He came to Washington in 1938 and married Gloria Louise Gardella. The two met while performing with the Columbia Light Opera Company.

He was a member of Marvin Memorial United Methodist Church in Woodmoor. He sang in the church's choir and was past president of United Methodist Men. He also was a Mason, a scoutmaster with the Boy Scouts of America, a past president of parent-teacher and citizens associations in the Woodmoor area and a member of Full Gospel Business Men's Fellowship.

In addition to his wife, of Bethesda, survivors include four sons, Alexander James Hill III of Clarksville, Robert Desmond Hill of Barre, Vt., John Wallace Hill of Omaha, and Jeffery Mark Hill of Poolesville; two sisters; nine grandchildren; and two great-granddaughters.