How ofter should you change the fuel separator, and if its bad, can it cause stalling? I had problems earlier this summer with my engine stalling because it was vapor locking. Turns out it was a mising screw in the fuel cell. Yesterday, I was running about 4000 rpm and she started stalling out again. I've ran about 7 or 8 trips with no problems since fixing the fuel cell and I'm confused about what could be causing it to do it again. I looked over all the vacume lines and re-checked the fuel cell and it all looks good. I'm hoping its just the separator.