This demonstration guide answers one field question about a broken flex shaft inside the tube. Measurements come before parts, and the notes are not a generic equipment FAQ.
Diagnose before replacing parts
Start with shaft continuity from clutch to head. That reading separates a broken flex shaft inside the tube from adjacent faults that share the same complaint.
If the measurement is out of spec, treat the flex shaft as the primary path. If it is in spec, do not replace the flex shaft just to complete a parts list.
Repair the failed system
The usual correction is the flex shaft, installed to the documented spec for this complaint.
A demonstration shop records the finding so the next technician is not repeating a guess about a broken flex shaft inside the tube.
Stop before you make it worse
Do not running without grease until the shaft welds itself. That shortcut hides the original measurement and creates a second failure.
If the machine still fails after the flex shaft is corrected, convert the visit to a broader diagnosis rather than stacking parts.
Written and published by Ridgeline Small Engine.