Hi Guys. Another new kid here. Working an a 1999 Craftsmen/Poulan 42cc. It would run and then die after a few seconds. Fuel filter had become detached from a split gas line. Walbro 391 carb. Rebuilt the carb and replaced fuel lines and primer bulb. The large screen in the carb was covered with gunk but the rest of the carb was not too bad. Now the problem. All back together and will not start. After a few tries with choke on, when turning choke off, it gets harder and harder to pull. Any ideas?