How to troubleshoot a brush cutter that is unstable at idle and easily stalls?

1. Oil supply failure (most common)
If the fuel ratio is wrong, there is too much/too little engine oil, or the gasoline has deteriorated due to storage and produced gum, directly replace it with a new standard mixture.
The fuel filter element is clogged, the oil pipe is bent and cracked, air intake is required, clean/replace the oil filter, and check the sealing of the oil pipe.
The carburetor is clogged, the oil needle is stuck, and the idle screw is improperly adjusted: disassemble and clean the carburetor, clear the oil passage, and fine-tune the idle screw again.
2. The air intake system is clogged and leaking.
The air filter element is covered with weeds and dust, and the air intake is insufficient and the mixture is too rich. Clean or replace the air filter.
The carburetor and cylinder air inlet gaskets are damaged and leaking, and the mixture is too thin. Replace the sealing gaskets.
3. The ignition system has weak ignition
The spark plug has serious carbon deposits, electrode ablation, and incorrect gaps: clean the carbon deposits, adjust the gap to 0.6-0.8mm, and replace it with new ones if it is damaged.
The high-voltage package is aging, the high-voltage line is leaking, and the spark is weak. Replace the high-voltage package components.
4. Exhaust blockage
Carbon deposits accumulate in the exhaust pipe and muffler. If the exhaust is not smooth and the engine stalls, remove it and clean the internal carbon deposits.
5. Insufficient cylinder compression
The cylinder piston ring is worn, the cylinder is leaking, and the cylinder pressure is low and the idling speed is weak. It is necessary to disassemble and replace the piston ring and inspect the cylinder.
6. Operation and damper issues
The damper of the cold engine operation is not closed in place, and the damper of the hot engine is closed by mistake; the damper is used properly, and the damper of the hot engine is fully opened.