Hydrostatic drive stopped working

[Ld454]

I have a 2005 yard machines 21hp with a 46 inch cut. I was in the middle of mowing my yard when suddenly the forward and reverse decide to stop working. When you hit the pedal the drive belts start smoking in the front so I’m assuming the problem is under the seat. What can be the cause of this?

 

[ILENGINE]

Post the model and serial number from under the seat so we can see which one of the various drive system that MTD has used over the years is on your mower.

 

[Ld454]

Here is the model and serial number. I didn’t have a whole lot of time to look at it today. I can only push it in neutral. When it’s in gear I can’t push it at all so maybe something is stuck?

 

[ILENGINE]

Appears the parking brake isn't stuck, but I would start by inspection the two drive belts. One from the engine to the variable speed pulley, and the other from the variable speed pulley to the big transmission pulley. Check to make sure something isn't jammiing the pulleys like a stick or even a rock. See if all the idler pulleys turn freely, and also see if you can turn the transmission pulley and the variable speed pulley.

 

[StarTech]

Just to note this has a CVT system with a single speed transaxle which is not a hydrostatic. A common mistake users have because has a pedal speed control.

As IL said the drive path for problems. Bearing failure in one of the idler pulleys or the variable pulley is likely. Brake calipers do stick but won't cause belt smoking problem in neutral which the OP didn't mention he tried that position.