Weed wacker wont start

Gary, diagnose where the problem really lays, do you have spark, is it getting fuel. PRESS THE HELPFUL BUTTON
String Trimmer Repair Help

How To Troubleshoot Your Weedeater to crank every time

http://cubcadet.custhelp.com/app/answers/detail/a_id/10653/~/basic-troubleshooting---hand-held-string-trimmer-(corded-electric)

ryobi weed wacker repair string trimmer wont start SIMPLE FIX

you added stabil but did you run the gas out of the carb? Take the carb apart and klean all with carb cleaner, spray in all holes. Check the plug gap of the new plug while your into the unit anyway the gap should only be 1mm.
Dennis

have you drained out all the old fuel and tried fresh fuel gas is only good for 30days in small engines

Two things which may be the problem: 1) carb need to be rebuilt or replaced, and 2) you need a new spark plug. The carb with shipping is around $50.00 from sears ( http://www.searspartsdirect.com/partsdirect/part-model/Craftsman-Parts/Grass-trimmer-weed-wacker-Parts/Model-3167918602008/0247/1503820/P0805032/00001?blt=06&prst=&shdMod= ) A sparkplug can be had at any small engine repair shop and most auto parts stores for less than $5.00 Start with the cheap solution... Also make certain you have fresh gas and that the oil mix is correct.

Be sure fuel lines are healthy...especially any places where they bend. If you feel confident enough you can go into the carb itself and check the inlet screen which is just under the inlet needle. These are a common trouble spot.
The screen will appear to be fine at first glance, but remove it and hold it up to the light and you'll find it to be swollen completely shut!
Might as well install a kit while you're in there. It's only about 10 bucks and the amount of time and effort it costs you is the same.
NOTE: Get a "REPAIR KIT" for your carb...NOT just a diaphragm kit.
Zama carb repair kits found here.
Walbro carb repair kits found here.
Hope this helps!

rebuild carb to fix problem.let me know if this help you.ok

Could be a faulty kill switch not allowing it to start, sounds like you covered all the things I would check.

Echo carbs have a little black plastic plug covering the High speed adj screw..CA air pulotion control bs..So get that little black blug out and give the screw a little turn open and u should be good to go..It worked for me..on a PBL 251 blower..My Echo weed wacker has the carb also..Go to Echos site and download the parts break down for your unit and look at the carb page..You will see the plug and HS,screw..happing wacking and blowing

Have these unit been stored with fuel in them or sitting around for a long period of time? If so the carbs may need to be overhauled. Also check for a clogged fuel filter and vacuum test the fuel lines for cracks.