Cool sweet 'new-looking' clean engine. Too bad about the throttle.
I have two with this kind of throttle. While
not my favorite type they do sort of work.
Question...can you remove the throttle screw?
If so, does the end look pointed? I think it
should. I tried to remove mine to check but it
started to bind as I tried to unscrew it so I
left it as is. I'm reasonably sure that your
steampipe/throttle are not blocked at all as
the engine ran well, so I think either the
throttle tip is bad or the seat is bad. I had
a Weeden #3 whose engine block was incompletely
finished, so there are occasional production
failures. I think your throttle rod is the
problem and you'll need to remove it.
Good luck,
Wayne