Accel pump feed and check valve?

[Dave Harmison]

I'm working on a FF carb and the accelerator pump isn't pumping. The check valve in the accel jet screw checks when I suck and blow through it. I installed my spare diaphragm and still no pumping.

It seems like to output of the accel pump is clear but maybe the input is plugged.

With the carb on the bench and the diaphragm cover removed, I filled the float bowl to the normal running level and no fuel runs into the pump chamber. Should it?

Should there be a check valve in the feed passage? My diagram doesn't show any.

If the feed passage is plugged how would you clear it out?

Thanks for any help.

[Steve Demeter]

really dumb question, but could you have 2 bad diaphragms

[Dave Harmison]

It looks good and is brand new, but fair question in this day of unknown part quality.