Little 2-stroke won't take gas

Homelite Bandit line trimmer, maybe 50cc. Many years reliable service.
Starts on choke per instruction manual. Even after it warms up, it won't take gas. Increased throttle results in decreased rpm. I have to keep it on half-choke to trim the weeds. It is recommended to run it at full throttle after it is fully warm.
Any idea why it won't throttle up?
Thx, P
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With these things and these symptoms the most likely culprit is a fouled carb. Or a clogged, collapsed, or leaking fuel line, fuel filter, etc. You could try spraying carb cleaner in it. If it's the carb, mabye a 30% chance that would solve it. Otherwise, if it's the carb you have to take it apart and clean it and get a rebuild kit.
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Check the compression also, if it is too low it won't run very well or at all.
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On Tue, 09 Apr 2013 13:46:03 -0500, Puddin' Man

Greenies from ethanol in the gas restricting the carb.
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Air filter clean? The air/gas ratio may be off.
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On 4/9/2013 2:46 PM, Puddin' Man wrote:

Most likely ethanol engine damage.
http://news.consumerreports.org/home/2013/03/gas-with-ethanol-can-make-small-engines-fail.html
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The need to use the choke to keep it running is your clue. Look for anything that is restricting flow of fuel to or in the carburetor, or anything that is letting too much air in somewhere else. Gummed up carbs are common in small 2 strokes. Sometime engines with lots of run time will start leaking at the crank seals enough to let air into the crankcase and lean out the fuel mixture. I've seen the same happen when throttle shafts get sloppy too.
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On Tue, 09 Apr 2013 13:46:03 -0500, Puddin' Man

Most of these things use the same basic Walbro carburetor. They just get jetted differently.You can usually find a new one on the net for $50 or so when you find the right number.
To clean it take the big screw off that end and the 4 screws off the other and remove the parts. Get a can of carb cleaner spray and shoot through all the holes. Then slip a small piece of fuel line over the spout on the can. Slip it over the brass port in the center of the carb throat and back flush it from there. Put it back together and try again
Other things, Clogged muffler, clogged filter inside the tank, cracked fuel line.
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