This demonstration guide answers one field question about runout that exceeds the documented limit after a strike. Measurements come before parts, and the notes are not a generic equipment FAQ.
Diagnose before replacing parts
Start with dial runout at the blade adapter. That reading separates runout that exceeds the documented limit after a strike from adjacent faults that share the same complaint.
If the measurement is out of spec, treat the crankshaft or short block as the primary path. If it is in spec, do not replace the crankshaft or short block just to complete a parts list.
Repair the failed system
The usual correction is the crankshaft or short block, installed to the documented spec for this complaint.
A demonstration shop records the finding so the next technician is not repeating a guess about runout that exceeds the documented limit after a strike.
Stop before you make it worse
Do not pressing a crank "back to true" in a vise. That shortcut hides the original measurement and creates a second failure.
If the machine still fails after the crankshaft or short block is corrected, convert the visit to a broader diagnosis rather than stacking parts.
Written and published by Ridgeline Small Engine.