My 2 poulan saws will run for 30 sec. and shut off ,,,new fuel ,new plugs,took carbs off and cleaned ,comp.140-150lbs.they will run with the choke on for 1 minute

If not already done you should replace the fuel filter in the tank

Try a few simple things first, clean the air filter, remove and replace the filter inside the fuel tank on the end of the fuel hose,check the fuel hose up to the carb for cracks and leaks, fit a new spark plug.

Unfortantaly its awaly the carb with this kind of tool Its a two stroke so you mix oil in the gas then it sits aruond for a couple of years until you need it and the oil gas mixture gets gummy and sticks the neddle valve witch lets the fuel into the float bowl and also shuts it off Try this get some starter fluid get the thing running on choke and spray it into the carb it may clean up some of your problems But the best thing to do is take apart the carb and clean it then it should work like new and its realy not that hard to do and you don;t need any new parts it can be done on a table in 20 minutes

Get some sta-bil fuel stabilizer. add twice the amount recommended on the bottle for storage to your mixed gas. Empty out chainsaw tank and refill with the new mix. Rub for 2 minutes, then shut off. Remove cover over carb and spray inside carb, soaking it down good and cleaning all internal surfaces visible - allow to sit overnight.
Next day
Spray down carb with carb cleaner for about 15 seconds. Start saw, allowing 2 minutes to warm up and reduce choke. If saw stalls, restart and spray inside carb as it runs with choke on - keep motor at the highest rpms you can as you spray - spray in 2 second bursts, not allowing motor to stall from spray. If it stalls, change sparkplug and try again. You have varnish build up in the carb and are trying to remove it so the carb will work without the choke. This may take some time but it is the exact procedure I used for my Poulan Team Realtree last spring - I spent about an hour spraying and staring before it ran without the choke.
Good luck!!

Do a tune up. It is easy. Just take out the carb and clean with any commercial carb cleaner nad change the spark plug.

INFO:
-Remove Carb and clean, you have a high speed fuel port clogged.

NOTE:
This would also be a good time to replace your fuel lines, Take photos before you start.

RECOMENDATIONS:
-Drain all fuel from the Saws fuel tank.
-Remove and REPLACE with a NEW spark plug.
-Remove and RELPACE with a NEW Air filter.
-With spark plug and air filter removed and fuel drained pull the starting cord many times 12 or so to ensure there is no fuel in the chamber and also check for a spark at the plug.
-RE-MIX WITH NEW FUEL your 2 cycle oil to the correct ratio in a clean fuel can. it is OK to dump some in the Saws fuel tank slosh around and dump out in an approved container for disposal.
-Hold off on putting back on the air filter until you have had it running.

Hope this Tip Helps.

R/
David

It is running lean. There is an air leak somewhere allowing to much air into the cylinder or crankcase. Continuing to operate lean may cause failure. If fuel delivery lines have no pin holes or cracks probably time for some professional help (pressure tests). Remove clean and reinstall the muffler (carbon fouling can also cause this). If the saw cannot exhale, it cannot inhale. HTH
Lou

It is running in a lean condition. Continued operation like that can cause piston and cylinder failure.
I'd take it in for repair estimate ($10) at the local chainsaw seller/mechanic. Explain the problem you are having, Probably a leaking fuel line. I'd expect a repair and tune up about $40-60. Your saw will perform better and your arm will thank you. If tuned ask what fuel/oil ratio they used (should be 50:1) and affix a label to your fuel tank. HTH
Lou

carbs dirty need cleaning. try adding some stabil you can buy at auto zone with fresh fuel it may clean itself out w/o having to remove the carb.

The prob is at the base of the carb. Its sucking air. Be certain to install a new gasket, making sure the both services are very clean. And the mounting bolts tightened equally! Frankster016