This demonstration guide answers one field question about a fuel-pump diaphragm that no longer moves fuel. Measurements come before parts, and the notes are not a generic equipment FAQ.
Diagnose before replacing parts
Start with diaphragm flexibility and pinhole inspection. That reading separates a fuel-pump diaphragm that no longer moves fuel from adjacent faults that share the same complaint.
If the measurement is out of spec, treat the diaphragm as the primary path. If it is in spec, do not replace the diaphragm just to complete a parts list.
Repair the failed system
The usual correction is the diaphragm, 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 fuel-pump diaphragm that no longer moves fuel.
Stop before you make it worse
Do not flipping a torn diaphragm to use the other side. That shortcut hides the original measurement and creates a second failure.
If the machine still fails after the diaphragm is corrected, convert the visit to a broader diagnosis rather than stacking parts.
Written and published by Ridgeline Small Engine.