This demonstration guide answers one field question about belts that hardened and blades that oxidized. Measurements come before parts, and the notes are not a generic equipment FAQ.
Diagnose before replacing parts
Start with first-cut cut quality and belt tracking. That reading separates belts that hardened and blades that oxidized from adjacent faults that share the same complaint.
If the measurement is out of spec, treat the belt and blade as the primary path. If it is in spec, do not replace the belt and blade just to complete a parts list.
Repair the failed system
The usual correction is the belt and blade, installed to the documented spec for this complaint.
A demonstration shop records the finding so the next technician is not repeating a guess about belts that hardened and blades that oxidized.
Stop before you make it worse
Do not making the first cut in wet, untested tall grass. That shortcut hides the original measurement and creates a second failure.
If the machine still fails after the belt and blade is corrected, convert the visit to a broader diagnosis rather than stacking parts.
Written and published by Ridgeline Small Engine.