walbro wt-669 carb

[01supercrew]

Only have this single question. After rebuilding the carb on my weedeater trimmer, I am wondering how the idle and high speed circuit works with this particular carb?
I understand that both the fuel pump and metering chamber are filled via the primer bulb attached. My only question (after trying with compressed and carb cleaner) is, how are the idle and high speed needles are getting fuel when there are three welch plugs covering the metering side. Other ones that I've repaired have a inlet, but this particular one does not? if any one could share some light on this would be appreciated!

thanks

 

[atschirner]

This service manual should answer your question:

http://wem.walbro.com/distributors/servicemanuals/WTseries.pdf