Originally Posted by Noah Mckenzie

I'm having the exact same issue with my old Yamaha three wheeler I replace the whole carburetor Now it only leaks sometimes it is much better than what it was but sometimes it'll still run bad when it starts to run bad it leaks gas out the Overflow the only time it runs bad those occasionally going through mid throttle in a year it'll start toboggan backfire but then it clears up the more i open the air screw the better it is

Originally Posted by heikoboehm

you will need to take it apart and remove the needle and float to clean it . be careful with the gasket and use a proper size screwdriver to remove the screws of the fuel bowl(so you will not strip the heads).use a small brush and a small pick or flat head screwdriver to carefully remove any derbies and spay with carburetor cleaner ,making sure to spray in all the holes and jets. be sure to clean the outside of the carburetor before you open it.