The main point is that it is a Walbro WT. Here is the service manual:
http://wem.walbro.com/distributors/servicemanuals/WTseries.pdfThe first thing you need to do is look at the gauze filter in the intake chamber. The second thing is to set the adjustments to the initial settings shown in the manual, and try to start the engine. If you can't get a satisfactory result with a clean filter and following the manufacturer's tuning process, you will have to go further. Usually the next step after that is a new diaphragm and a clean, following the manual throughout.
My concern is that you might have started out with a clogged filter, then compounded the problem by tweaking the adjustments without cleaning the filter first. That is why I suggest the approach I've described.
