Analyze and summarize the common faults, and then solve the problem.

First: small flow is not self-styled
The reason is that in the small gasoline flow meter, the flow rate is low, the suction effect is small, the pressure difference between the upper and lower chamber of the switch film is small, can not overcome the elasticity of the spring so that the self- To solve this problem, it is necessary to reduce the spring force of the spring.
Second: refueling guns are not self-styled
The reason for this is that the upper surface of the diaphragm is sealed with the outside, for example, the upper part of the plastic cap is not tightened, and the "O" type seal on the adapter and the sub-seat of the oil gun is damaged. The diaphragm can not form a pressure difference. To solve this problem need to tighten the plastic cover pressure wire, replace the "O" seal.
Third: refueling guns often self-styled
The reason is that the nozzle inside the electronic diesel fuel pump is blocked by foreign body, poor air intake or open the membrane on the cavity of the spring caused by the spring is too small. Solution: clear the foreign body in the intake pipe, stretch the spring to enhance the elasticity.