Yes the diaphragm can stick badly. I pour a little alcohol in the fuel bowl to cover the pump check valve then work the pump shaft up and down.
This pumps the alcohol in side the pump. Let it sit a while then try again later.

Be careful not to warp the pump housing by prying too hard with a screwdriver.

Last edited by buoymaker; 03/15/2022 11:57 PM.
"Adding CFM to a truck will only help at engine speeds you don't want to use."
"I found there was nothing to gain beyond 400 CFM."