I need education on the Thermoquad "staged accelerator pump" , that gives an additional shot when the secondaries open

Just went through 3 rubber accelerator pumps that didn't work at all. Had a leather pump and it worked first time perfectly. Not sure why the rubber ones failed. I would have thought that they might work for a while until the ethanol (ugh) in the fuel caused them to swell, but they didn't work from the start. Going to purchase a few more leather accelerator pumps, despite their current cost just as backup.
You always need to look at the acc. pump bore. Many times they are scored or corroded. Leather might be more forgiving. If your TQ looks like the ones that UTG has gotten off the Titanic and says they are all junk, you might need another top.