My fan was turning too fast, had to slow it down. I simply put a 6 3/4" pulley over top of the 4" pulley. I got a slightly longer fan belt and I am as happy as can be with it.

If you look carefully, you can see both pulleys.
http://i365.photobucket.com/albums/oo91/1953panel/DSCN02251_zps529d5ab8.jpg?t=1366584373