I need a diagram for a murray riding mower model 40508x92 for a drive motion belt 37x87 it is a 2000-2003 mower replaced the belt but the mower will not move

Did you use the correct width belt? You should be aware that a belt does not grip and turn a pulley by the tension. It of course must have the correct tension but the griping action is cause by the fact that when the belt bends around the pulley it's width expands. That expansion grips the walls of the pulley. Incorrect width won't have any gripping power.

Hi,
The breakdown says it is correct. It can be seen at one of the breakdowns at this link:
Murray Parts Lists Murray Lawn Mower Parts lists
It is just a Murray 40" Walmart machine and the routing is pretty straightforward. The other question would be "Have you had a rear wheel off and not put the key back in? "Easily seen by seeing the axle rotate backwards in the center of the wheel.
Peace,
Clarke