here's a bit more I found of interest:

But it was Sam McCloud that Weaver called "the most satisfying role of my career." The show, which ran from 1970 to 1977, featured him as a New Mexico lawman cast on the streets of New York City with a horse, a sheepskin coat and a folksy manner that belied his shrewd crime-solving talent.

Off-screen, Weaver served as president of the Screen Actors Guild and was a vegetarian and activist for environmental and charitable causes.

He served as president of Love Is Feeding Everyone, which fed 150,000 needy people a week in Los Angeles County. He founded the Institute of Ecolonomics, which sought solutions to economic and environmental problems. He spoke at the United Nations and Congress, as well as to college students and school children about fighting pollution.