Replace the oils in both tranny and oil injection tank with new.
Flush gas thru system and probably better remove and clean the carb and all passages it has,iincluding the main jet and emulsion tube or diffuser. New spark plug and bleed injector pump lines until no air bubbles left in new 2-stroke injector oil. Clean and check operation of ignition points. Check for spark before cranking too much. It's also a good idea to squirt a lil' 2-stroke oil into the cyl and turn the engine over to make sure rings and piston are lubricated.
Go to Fred's Guide on this site and readi t and use it. don-ohio