1, carburetor leakage. When the gasoline engine stops, if the main nozzle leaks continuously, the reason may be that the balance lever of the carburetor is adjusted too high, or there is dirt in the needle valve, the needle valve seat should be cleaned and the balance lever should be lowered appropriately until no oil leakage. 2, spark plug does not jump fire. In the case of normal high-voltage line spark jump, the spark plug should be removed first to see if there is carbon deposit, whether the electrode is wet or whether the gap is normal. 3, the amount of spray can not be reduced or spray. When the engine is working, check whether the air inlet valve is open, whether the medicine box cover is leaking or whether the rubber washer is damaged; secondly, check whether the intake pipe in the medicine box is twisted and impassable, whether the nozzle, switch, adjusting valve and filter mesh air hole are blocked, and clean and dredge when blocked. If the spray can not be sprayed vertically, it may also be caused by the excessive lifting of the nozzle. The sprinkler should be lowered to maintain a 60~70 degree angle with the ground. 4, the liquid enters the fan. First check the intake rubber apron. If damaged or lose elasticity, replace the new parts. If the gap between the intake apron and the intake plug is too large, a layer of adhesive tape can be wrapped around the intake plug to increase the tightness of the intake plug and the apron. If it is caused by the drop of the transparent plastic pipe between the air inlet plug and the filter screen, it needs to be installed again. 5. The hand switch is leaking. First check whether the switch cover is screwed tightly, if it has been screwed tightly, then check whether the sealant ring on the switch core has been worn, has been worn to replace. Then see whether the lapping contact surface between the cone surface of the switch core and the shell is sealed, if the seal is not good, it needs to be lapped to make it close.