I had removed the battery several years ago, but left the batter hold down bolts. Upon further investigation I discovered that one of those bolts had fallen down and was not allowing the idler pulley to fully engage. It is amazing that it took several years for this to happen. The hold down bolts are now removed and the mower runs and mows great. Not bad for a 1984 model. Go Yazoo!!
Jerry
July 2010