just mine... well I have three one: in DECENT conditions ( in my car ) and two more that could it be fixed, tuned somewhere, somehow... just that still dunno exactly how LOL... HAVEN'T TRIED EITHER again since I have the best I could get working already mounted. I'm having some issues on the very first initial gas press quite often... dunno if acelerator pump/linkage adjustment... or something else. I already tried changing pump itslef ( rubber, leather ), check valve ( roller, rubber ). I still can make some other experiments. I have got changes on every try, some better, some worse. Right now is better than last time. I changed the pump for leather kind 2 days ago. A friend of mine told me SPREAD OUT the leather to get a better seal against the walls ( I didn't make that first time I mounted the leather pump kind ) did work, at least better than initially.

I have read manteniance and rebuilt manuals several times, but still don't get some stuff. maybe a technical language issue

and failed on one try on a friend's car