( 1 ) fuel injection pump parts pump fuel injection pump easy to damage and influence in the calibration process easy to make or use the pump cracks , the oil valve seat tightly threaded hole damage , internal plunger pump plunger bore sleeve convex sets leakage occurs , such as supporting the emergence of a plane in contact with the shoulder pits or scars.
① oil valve seat tightly threaded hole damage , can cause a tight seat of oil or oil leakage phenomenon of channeling between the pump and the oil , thereby reducing the injection pressure, can also cause serious injector is not fuel injection.
② support plane plunger sleeve bore and piston sleeve shoulder contact to produce pits or scars, this injury is more due to the tight seat assembly between a tight oil . When the bearing surface pits or scratches appear , tilt phenomenon causes the plunger suit behind. When the plunger up and down movement will cause partial wear even stuck and so on.
( 2 ) fuel pump seal inspection methods
Fuel pump low pressure oil chamber seal ' test is generally carried out after the general assembly at the fuel pump .
① The fuel pump assembly is fitted to the test stand bracket.
② injection pump cam shaft is rotated in order to check the flexibility of the fuel pump parts .
③ Check the amount of oil inside the fuel pump assembly meets the requirements .
④ The adapter is fitted to the fuel injection pump test bench shaft, and then connect each cylinder corresponding pressure tubing .
⑤ open test bench power switch and release the fuel pump bleed screw.
⑥ button is pressed the motor pump oil chamber to discharge the air inside the fuel pump .
⑦ adjustment into the low pressure chamber of the diesel oil pressure to 0.45MPa, and then observe whether there is oil leakage or pump leakage , etc.
( 3 ) a simple method to repair the pump after injury
Supporting plane internal plunger pump plunger bore sleeve shoulder sleeve contact appears uneven phenomenon, making available the old plunger pump into ground rods for internal grievance at the bed in the mirror grinding or cutting the support plane mirror . After the pump repaired , to the first round proper thickness plus a washer plunger sleeve before assembly , but also for low-pressure oil chamber tightness test after assembly is completed.