Well, I like this. It's kindof like a pop quiz isn't it? Here's my first thought (actually, my first thought in response to your question, I don't remember my first thought), keeping in mind, where I am, we're sucking up Jack Daniels and doing the Kareoke (spelling?) to Van Morrison's "Oh, The Water" or maybe you know it as "It Stung Me." Anyway, if the choke is wanting to be on in order to keep running, it's wanting less air and more gas. This happens a lot with motorcycles that've sat around a long time, the gas has gone bad, and they don't want to run 'cause the bad gas can't get through the stopped/gummed up orifices. Dump the gas from the tank. Make sure the hose from the fuel filter to the carb is clear. Make sure the fuel filter is clear. Make sure the hose from the primer bulb back to the tank is clear. Remove the back of the carb: the side opposite of the primer bulb; keep track of the little screws and how the diaphragm goes on, remove the tiny screw that holds a tiny needle & seat & itty bitty spring (Be real careful on this one). Remove the 2 screws holding the primer bulb on, and remove primer bulb. Set the unit in an oil drain pan, put on some goggles and rubber gloves, and spray all the little holes you've uncovered on each side of the carb with carb cleaner (remember, in CA, they say carb cleaner causes cancer). Careful when you do this 'cause some of those orifices (holes) will be pointing back at you. Do this enough so you think you might have cleaned them (the orifices). Then carefully put it back together. Put in fresh gas. This may not be the problem, but it's an easy way to eliminate some things. Take your time. Remember, this unit has been sitting in the back yard for awhile. It might take some effort to straighten out. Clean orifices, clean air filter, and clean, fresh gas, then let's try again. And the plug is good, right? Anyone else out there wanting to jump in on this, please go ahead. Your input is appreciated. Van Morrison is on "Wild Nights Is Calling", and a cute babe (I'm married to her) is asking for a drink. Life is fun! Gotta go. PS Your Echo doesn't have a fuel pump, does it? Just kidding; that's a Briggs & Stratton joke.