Small Engines (Lawn Mowers, etc.): bowens bl100 wont run, gas filter, fuel mix

Question
approx 1 yr old, new plug and gas, just cleaned air filter.  tried to start per instructions, pump bulb 10, 5 pulls on choke 1, pull until start on choke 2, once warmed up move to chock 3 open.

problem is i get it to start on choke 2 but it wont stay running. But it will stay running if i flip it manually between choke 1 and 2 (back and forth, back and forth, back and forth,etc.....)during warm up but then stalls when i stop flipping the choke back and forth.  even after warm up i have to manually  "play/flip" with the choke to keep it running barely.    It seems to me like it is either not getting enough gas/air or to much of gas/air which tell me possibly it needs a carb addjustment  i need an EXPERT like yourself to guide me through the problem resolution procedures.  I dont have a care in the word about dirt and greases, just need this running.   i saw something in a previous post which i dont know if this may apply to this situation, but is there a gas filter in the tank?  if so i have never known or changed it in 2 yrs  FYI

I sincerly appreciate any assistance you can give,
thanks mike

Answer
Have you checked the Owner's manual for the carb adjustment?  The link below will take you to the Operator's Manual but you need to enter your serial number.

http://www.mtdproducts.com/webapp/wcs/stores/servlet/OwnersCenterView?storeId=10...

Is there one or two adjustment needles on the carburetor?  Keep in mind there will always be an idle adjustment, the other adjustment(s) will be air/fuel mix needles.

Is there a carburetor manufacturer name stamped on the carb?  Example is Walbro, Zama?

Let me know.
Eric