td 9 wont start on gas

Am having the same problem. Have removed carb, checked timing, replaced magneto. Sometimes it will run for a short time other times nothing. New plugs put in, cleaned out the carburetor. I am at a total loss. Have maintained it for 20 years without a problem. I checked butterfly valves, a bit of WD 40 to make sure everything was opening okay. If you have your carb off check to see if the fuel inlet tube is open, look in parts book- I can't seem to get much air going through mine - think that may be the problem. Have you put gas in the plugs to see if it will start - might eliminate a carb problem - otherwise check mag, plugs, timing which you probably have done already. I'll check back.