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