Repairs Craftsman 917.272680 has no drive powrer

[rocky4]

Have problem with craftsman riding mower going up an incline(hill). Belt is tight and turning transmission ok, so it seams.
Checked oil in transmission, OK. Just has no power going up hill. Runs ok on level ground. If you have the mower jacked up from the rear ( rear wheels off ground) and you have the engagement lever in back engaged, should you be able to feel tension on wheels if you rotate them by hand and the fan should turn?

 

[rocky4]

OK. I found the problem. It was the drive belt after all. I replaced it and all is well. You just can not trust looks for being good.
It had stretched just enough to not work. Hope this helps some one else.