Remove the shroud, remove the fan, belts, pully, crank pully, timing cover. And yer there.
Sounds like the tensioner may have broken. There is a spring activated tension plate with a tab that prevents it from moving out of alignment. This can break and and you'll lose all tension. Or it could have come loose, broken tensioner, or spring.
Happened to me on the trail once, but I was able to fab that tab with a 70 amp arc welder, and it lasted the life of the engine.
Neal the Zukiguy