If a fuel dispenser is dispensing fuel too slowly or the nozzle shuts off when fuel flow increases, it is likely due to issues with the self-sealing mechanism of the fuel nozzle.
Self-sealing nozzles operate with an air intake system that prevents overflows. A small air inlet hole near the nozzle tip helps regulate the flow. If airflow is restricted or blocked, the nozzle may shut off prematurely. Additionally, a malfunctioning auxiliary valve can also cause the nozzle to shut off unexpectedly, though this issue is less common.
To resolve the problem, check the following:
Remove the nozzle and inspect the air inlet hole for blockages caused by debris or oil buildup. Clear any obstructions to restore proper airflow.
Examine the air passage connecting the nozzle tip to the gun body, ensuring it is unobstructed and functioning correctly.
If the issue persists, inspect the auxiliary valve for potential faults, as a faulty valve can also trigger premature shutoff.
In most cases, clearing blockages in the air intake system resolves the issue, restoring normal fuel flow.