Roger on those carb-centred thoughts Norm. It would surely have to be a casting crack or something like failed brazing for it to repeat itself both before and after I dismantled the carb to clean it. The trouble with buying another FS36 2nd-hand for swap-over purposes is that the owner might be selling it due to the exact same problem as what I'm having with mine...
I might also try some further googling of the problem, but from the Walbro point of view as opposed to the Stihl.
Many Thanks again,
Moby Mick.
