1. Check the plunger for scratches and rust, and replace it with a new one if necessary.
2. Check the cooperation of the plunger pair. Insert the end of the plunger into the plunger sleeve and tilt it at about 60°. If the plunger can slide slowly under its own action, the fit is good.
3. Check the tightness of the plunger pair. Hold the plunger sleeve with your hand and block the oil inlet on the top and side of the plunger with two fingers. Use the other hand to pull out the plunger and feel a strong suction. Release the plunger and immediately retract it to its original position, indicating that the plunger pair is well sealed. Otherwise, the plunger pair should be replaced.
4. Check whether the auxiliary decompression ring belt of the oil outlet valve is worn and has steps or scars, and replace it if necessary.
5. Check the coordination of the oil delivery valve pair. Block the lower hole of the oil outlet valve with your finger, and use another finger to gently press the oil outlet valve downward. When your finger leaves the upper end of the oil outlet valve, it will automatically spring back to its original position, indicating that the secondary seal of the oil outlet valve is good, otherwise The oil delivery valve pair should be replaced.
6. Check the tappet body. The standard gap between the fuel injection pump body and the tappet body is 0-0.03mm, if it exceeds 0.2mm, the parts should be replaced.
7. Check the gap between the plunger flange and the groove of the control sleeve. It should be 0.02~0.08mm. If it exceeds 0.12mm, the control sleeve must be replaced.
