Mower wont move when put in gear

[IL-Mow]

I have a murray mower that has a manual transmission with a 2 pulley system, one for the blades and one for the transmission to make the tractor go.

Mower starts and blades run fine. However, when you pop the clutch into any gear, 1st-5th or reverse the transmission belt stops spinning. When in neutral though the pulleys and transmission belt turn in the front and the back. Could anyone help me figure out what might be possibly wrong?

 

[webuyanymower.com]

With the engine running and the clutch pressed down the transmission belt should not be moving
When you put the machine into gear and lift the clutch the belt should then go round a drive the rear axle. If it does not then the belt could be worn out or stretched.

 

[DaveTN]

I have a murray mower that has a manual transmission with a 2 pulley system, one for the blades and one for the transmission to make the tractor go.

Mower starts and blades run fine. However, when you pop the clutch into any gear, 1st-5th or reverse the transmission belt stops spinning. When in neutral though the pulleys and transmission belt turn in the front and the back. Could anyone help me figure out what might be possibly wrong?

What does it do when the blades are DIS-ENGAGED and you put it in gear to move? With the clutch IN and the gearshift engaged say in 1st...it should still sit there. When you let up on the pedal, it should go forward. Drive pulley belt could be slipping or off entirely. Some mowers are notorious for throwing belts. Check the alignment of the clutch pedal bracket holding the idler pulley, make sure that idler pulley is running true.