This demonstration guide answers one field question about nests that starve the carburetor of warm air. Measurements come before parts, and the notes are not a generic equipment FAQ.
Diagnose before replacing parts
Start with heater-box airflow. That reading separates nests that starve the carburetor of warm air from adjacent faults that share the same complaint.
If the measurement is out of spec, treat the heater box as the primary path. If it is in spec, do not replace the heater box just to complete a parts list.
Repair the failed system
The usual correction is the heater box, installed to the documented spec for this complaint.
A demonstration shop records the finding so the next technician is not repeating a guess about nests that starve the carburetor of warm air.
Stop before you make it worse
Do not starting with starter fluid in an enclosed garage. That shortcut hides the original measurement and creates a second failure.
If the machine still fails after the heater box is corrected, convert the visit to a broader diagnosis rather than stacking parts.
Written and published by Ridgeline Small Engine.