Small Engine Troubleshooting Problems? Ask a Mechanic Now.
Does the carburetor have a all metal needle valve, and the seat in the upper passage is rubber? If so, the upper passage is plugged at the rubber seat. Can be debris, or can be the rubber seat itself. If that is the case, a new needle and seat will fix it.
If it has all metal needle, it will have rubber seat. Remove the inlet fule line and blow from there , through the passage to check. To replace the seat, you use a pick or wire to get it out and a drill bit end or a dowel to push in the new seat.