Remove center and right side cover
1. Unscrew the two screws on top of the carb and slide the entire throttle assembly up out of the carb and leave the spring and slide and cable attached to the carb top. Move the assembly out of the way to one side.
2. Loosen screw on air filter box clamp and remove the air filter. Careful there is a little round mesh screen that may fall into the engine area.
3. Remove fuel inlet pipe by removing the screw (leave the fuel line on it). Lift it up and out of the way. There should be a hollow cylinder shaped plastic filter and a round orange or red fiber washer under the fuel intake. Use a long blade screw driver to reach the filter and slide it up the blade to remove it from the carb.
4. Use a 8mm screwdriver type socket driver or an opened end 8mm wrench to loosen the nut that secures the carb to the intake manifold pipe. Use a little WD40 on the pipe to help slide and wiggle the carb toward the back of the engine. Remove the carb up through the engine compartment.
5. There is a cylinder shaped plastic shim that may stay on the intake pipe when you remove the carb or may come off with the carb. Either way you need to remove it from the carb to access and clean out the Idle Jet.
6. While you have the have the carb off and the fuel line open at the carb end, test your fule petcock switch in the UP (Reserve), Down (Full) and level or horizonital for OFF. You should have fuel flow in the UP and Down positions if you have enough premix gas in the tank.
Do steps 4 thru 1 to reinstall carb
Put in a new plug NGK B6HS gapped at .020" You can also use a B5HS.
Don't forget to also check the rear hub for oil. Takes 80-90 wt gear oil.
Good luck and let me know if you need any parts, I have a good inventory of New and used Vespa moped parts