1. A 'classic' 2-stroke engine has the carb feeding into the crankcase,
where the fuel/oil mix lubes the bearings. What happens to that fuel?
It seems it must end up getting burned? If so, does it need to
re-vaporize?

2. Our Stihl trimmer (FS36) has a membrane carburator. AIUI, these are
supposed to operate in any position. So, what drives the fuel from the
tank to the carb? I'd thought that the fuel tank was (slightly)
pressurized for this. (There's a 2nd hose between them, running through
the primer bulb.) But, when I remove the carb fuel hose, with the
engine running, no gas comes out of the hose. Is fuel just pulled by
the venturi vacuum?

Thanks,
George