No fuel in carburetor float chamber
The carburetor inlet passage is blocked. The analysis and exclusion steps are as follows:
Open the carburetor float chamber and check whether the oil inlet needle valve is driven down when the float falls. If the needle valve is still tightly combined with the needle valve seat without moving with the float, it can be judged that the needle valve and the valve seat are bonded to cause the blockage of the oil inlet channel. This fault is generally caused by the condensation of gasoline colloid between the needle valve and the valve seat. Can be cleaned with alcohol or acetone. Such failures often occur on motorcycles that have not been used for a long time. In particular, engine factories and motorcycle factories have not exhausted the gasoline in the carburetor float chamber after installation. In the case of a slightly longer inventory or sales period, gasoline gel condensation will occur, resulting in carburetor performance failure.
Remove the float and needle valve, connect gasoline from the oil inlet port of the carburetor, and observe the outflow of gasoline from the valve seat. deal with.
In addition, a blocked oil circuit indicates that a large amount of impurities have entered the interior of the carburetor. The root cause is the failure of the gasoline filter. Therefore, when cleaning the carburetor, it is necessary to check the gasoline filter.