poulan trimmer will not run w/ choke off?
Someone gave me a barely used (8ish yrs old) Sears 32cc straight shaft string trimmer for string or blades. The fuel lines were rotted away but other than that it appeared to be fine and looked to have only been minimally used perhaps a couple few times.
What I've Done:
I've replaced the lines, filter, primer bulb, inspected the plug, cleared all the passageways in the carb with carb cleaner (appeared to be quite clean) and added fresh 40:1 fuel (w/ Hursqvarna 2 cycle oil). Pulled and inspected the intake manifold (it's plastic!) and appears clear of obstructions etc. Pulled, inspected the muffler (only held on by springs) and it's clear and like new w/o even any external surface rust yet. The line w/ the filter has several inches inside the tank allowing the filter to flop around a bit so it's always well submerged in the fuel when holding upright. I did leave a couple inches on the return line in the tank (should it be trimmed to only extend a little into the tank? or does this matter? - I don't see how it does - but just asking...)
What It's Doing:
Following the instructions to prime, sputter in full choke, flip to half-choke - fires up, wait a while and no joy when switching to choke off.... It actually runs fairly well in half choke. It's a little boggy as you might expect but if you're slightly slow on the trigger (take a second vs a fast squeeze) it runs up the RPMs fine. After running 10, 20 or more minutes I've tried flipping the choke off from idle, part throttle or full throttle - stalls out every time within 1, maybe 2 seconds. I've tried it w/ the air filter installed and removed.
The mixture screws on the Walbro carb are recessed within a boss and only have finely serated outer edges, no cross or Philips pattern etc. E.g. it appears to be designed to only be adjusted w/ a factory specialized tool and probably intended to be left alone. I 'could' cut off the boss and cut slots in the mixture screws if necessary. It should be at the original factory settings and it probably has less than a couple/few hours on it since purchased new.
Anybody encounter a similar problem or have any further suggestions? I could modify it to adjust mixture screws...? I could also just run it at half choke all the time...?