Troubleshooting a problem that's eating up the lower drive belt after a few hours of use. Found that a idler arm tension spring was missing.. Everything works fine now but starting to see some wear on the new belt after a few minutes..
A symptom of missing Idler arm spring will be that its difficult to change gears(fwd,N,Rev).
Update: Even though the idler arm spring was missing and causing other issues, the main problem was the cheap after market belts were slightly a different width and shape than the OEM belt causing it to ride deeper into the variable speed pulley where there were machine burrs... Ahhh rookie mistake.. Use Genuine MTD belts. Exploded Parts list:
https://www.troybilt.com/en_US/operat...
Drive Belt Routing Diagram:
https://schematron.org/troybilt13wx...