31cc ryobi weedeater wont start

I've had similar trouble. I removed the plastic cover to expose the fuel lines. I've had to replace all of them as each one had dry rotted, split or had holes. There are four runs of clear plastic fuel line. Check all your lines and then check for any of it being plugged up to the carberator. The primer bulb should develop some pressure when all is good.

Please elaborate on what you meant by "added oil to the carb." If you mean that you have mixed the recommended amount of 2 cycle oil to the gas mixture, that is good. If you meant that you really did put oil into the carb, that is not good.

Are you using fresh gasoline with no alcohol in it? The choke setting is also critical. Does it even fire? Any smell? Any smoke? Any gas "leaking" from carb? Did you clean the air filter? If you let it sit for a half hour and try starting again, what does it do?

The gas lines are not as rugged as I think they should be. It is not unusual to have to replace them after only a couple of years.

You will need to check the fuel lines for cracks/breaks.

You will need to disassemble the carburetor and spray with carb.cleaner. Make sure the small screen in the carb. is free of debris. Use a Den Tek Brush, (http://www.drugstore.com/products/prod.asp?pid=165357&catid=1152), to clean the small portals in carb. These portals can become blocked. Reassemble and start.

(NOTE: If the carburetor parts are more than four years old, and depending on the use, you will need a new carb. kit if the cleaning doesn't work.)

If you need further assistance, just let me know.

Jim