Small Engines (Lawn Mowers, etc.): Craftsman Bushwacker, carburator, tank fuel

Question
Model 358.795020 17" 32CC weedeater:
Won't stay running - shuts down when taken off full choke.  Have to adjust the Low & High screws EACH time to get it started (usually the L screw turned until it almost comes out and the H screw turned mid-way) and then readjust them down (L to about 2 turns and H almost turned off).
1.  Need arrangement of Fuel lines, e.g.  Large Diam. line (in-tank fuel filter) to carb port (@ floppy diaphram side) is this correct?  The Sears techs at the "Call" # don't know!!
2.  Initial L & H screw settings? 1 1/2 turns from seat and 3/4 turn, accordingly?
3.  The primer bulb has 90% air/10% gas coming through it when pumped, is this correct? Have ordered a new carb gasket.
Thanks for any help you can render.

Answer
 Hello David:

 Remove the Muffler and Check the Exhaust Port for Blockage(carbon). Check the Muffler and Spark Arrestor Screen for Blockage too. If the Exhaust and Muffler are Good, then Remove the Carburator; Clean and Rebuild it. Soak the Carburator Overnight in Cleaning Solution. Then Blow All the Passages Out with Compressed Air.  The Varnish that Gas Forms Inside the Carburator has the Passages Inside the Carburator Restricted and Causing this Problem. If the Primer is Pulling Fuel Into the Carburator, then the Fuel Lines are Correct. the 90%, 10% is right for the Primer Bulb. I Usually Start with Both L & H Screws at 1 1/2 to 2 turns Out from Seat. Then Rev the Engine to Full Throttle and Set the H Screw so the Engine Runs Smooth. Then go to Idle and Set the L Screw so there is No Hesitation when Going from Idle to High Revs. Then Set the Idle. Hope this Helps. Let me know what Happens, Please. I enjoy knowing the Outcome. Thanks.

 Good Luck

 Respectfully

 John