On May 5, 3:22*pm, George wrote:
I have a Stihl FS36 trimmer, which has a Walbro diaphram carb. *

It starts OK (after priming), but only runs for 10-15 secs before
rapidly losing power and dying. *After it dies, I can restart it (after
pumping the primer bulb), and it does the same again.

IMO, it acts like it's not getting gas. *There's no smell or other
evidence of it flooding. *But, (a) pumping the primer bulb while it's
dying doesn't seem to help; and (b) when I take the carb apart post
mortem, there's gas in the chamber under the diaphram. *Also, when I
operate the needle valve, gas flows up into that chamber. *So, the gas
seems to be there.

Any thoughts would be appreciated.

Thanks,
George

(NB: I have removed the spark suppresser screen.)

Did you ever leave gas in it like overwinter, My fs 36 got like that
so I had the carb cleaned after leaving gas in it one winter.