This has probably been asked before but I haven't found it.
I have a Craftsman trimmer model 358.795120 that wont start. I have replaced the fuel filter and hoses (the hoses had decayed and were leaking) I can put raw gas directly into the carb (Walbro wa226) and it will start and run a second or two until the gas is gone. Primer bulb is in good condition but it appears that something is preventing it from filling. Any suggestions?

 

Sounds like the carb its self may restricted. Install a kit and clean the carb in a bath carb cleaner.

The primer bulb actually draws fuel from the tank through the carb to the primer then back to the tank.