Small Engines (Lawn Mowers, etc.): Walbro WT-539 Carb Rebuild, brass cylinder, john thanks


Question
John...thanks for the info about the plastic black/white mixture screw stops.  I removed them, not damaging them severely, but knowing it didn't matter anyway.
Next issue:  I have all componenents removed from the carb, per a Walbro diagram, except for the "nozzle" and "check valve."  Do I need to remove them and, if so, how?  Both parts appear to be brass, but not sure which is the nozzle and which the check valve based on the diagram.  I removed a Welch plug to expose a deeper-seated brass cylinder that extends into the carb throat at the Venturi.  The second part appears as a smaller brass donut nearly flush with the carb body.
Finally, do I need to remove a larger Welch-plug looking disc that appears to be pressed into a cavity next to the brass donut again almost flush with the carb body?
As info, when I tried to access the Walbro website to get the exploded diagram, Walbro presented me with an intranet login screen which surprised me.  I had accessed that site before and didn't run into that before.  I just updated my MSN Explorer, which may have messed something up, I suppose.
Thanks again for all your unselfish and sound help!

Answer
 Hello Rodney:

 I got the Same Request Over a Few Days, so I called them and Now the Site is Back Up. You have Disassembled the Carburetor more than Enough. Don't Disassemble Any Further. Soak the Carburetor and then Blow Out the Passages with Compressed Air and Install New Kit. Hope This Helps. I am here if you Require more Assistance. Let me know what Happens, Please. Thanks. Be Safe.

 Good Luck

 Respectfully

 John