Install new drive belts and mower still wont move forward or reverse.

Usually under the seat you will find the drive belts check for proper install find belt route guide for instal. As you mash the pedal to go it will move a series of pulleys that will engage the belts to make it move. Look to the front pulley under the seat remove batteries to access the view of the front pulley. You should have two drive belts. One from the engine and the other just under the battery. Hope this helps.

Belts dont move mower back and forth, there is a bar that engage the hidrolic transfer, perhaps you move it and you have not tracking power, or, there are a series of rods that actuate the hidrolic, coud be that any of those rods came undone, if any of these to scenarios is happening to you, consider have the hidrolics chec out.
Good luck to you.

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