Small Engines (Lawn Mowers, etc.): transmission slipping, shift on the fly, speed shift

Question
I have a 2007 yard machine, 7 speed, shift on the fly. The transmission is slipping only in the forward position. If I push on the linkage it will move, when I let go, it stops and grinds. I was told that the belt may be stretched, and I will need a new one. If this is true, how hard is it to replace, and is there a schematic that shows how it goes on.
Thanks

Answer
Bob,

Yard Machines Is MFD by MTD http://www.yardmachines.com/webapp/wcs/stores/servlet/topcategory_10451_18503_-1
fortunatly they do have a schematic to show you how the routing of the belt runs In a service manual purchaseable from the above website.  But i will tell you how to do it so its done right.
Take a Notebook and look under the machine at how the belt is routed before taking it off.
Make sure you illustrate the front Pulley with "FP" and the Tranny Pulley "TP" along with the Clutch tensioner Pulley "CP".
And yes a new belt would help this problem If that does not help then please get back with me.