(1) The oil pump wears and causes the diesel oil to enter the oil
This fault is manifested as: the oil surface is obviously raised, and it is accompanied by the diesel smell. In severe cases, it is oiled from the oil supply port or the vent hole. For piston-type oil pump, diesel enters the oil, there are only two ways: diesel can directly enter the lubricating oil of the lower part of the fuel pump from the backlash of the roller body of the oil pump; the wear of the plunger of the fuel pump is overrun, resulting in The internal leakage of the pump (which will affect the normal start of the engine in severe cases) will cause the leaked diesel to flow into the lower chamber lubricant.
The solution is to open the side cover of the fuel injection pump and start the engine. If the piston of the sub-pump is out of the diesel, the wear of the plunger of the sub-pump is over-limit. It is necessary to change the plunger and it should be verified on the test bench. Fuel injection pump. Remove the oil pump (do not remove the connecting oil pipe) and pump the oil by hand. If there is diesel fuel in the side gap of the oil pump roller, it proves that the oil pump is faulty. It is also possible to remove several connecting oil pipes of the oil pump, tighten the hand oil pump, block the oil outlet of the oil pump, and introduce a gas with a pressure of 0.4 MPa from the oil inlet port. If the gas flows out of the back side of the roller, the oil pump is proved. If it is faulty, it should be replaced.
(2) Oil leakage at the high pressure oil pipe joint of the oil injection white pump outlet
The reason for this failure is that the concave oil outlet of the fuel injection pump and the convex high-pressure oil pipe joint are caused by wear and tear, resulting in poor sealing and oil leakage. The solution is that the fuel pump concave joint on the fuel injection pump is provided in each school pump factory, and can be given free of charge with the school pump. This method can also be used for oil leakage at the connection between the fuel injector and the high pressure oil pipe. it is good.
(3) The fuel injection pump shaft is broken
If the four fine bolts of the fuel injection pump are not tightened, the loose pump and the pump base will dry dry when the engine is working, and then there will be a gap. The longer the gap is, the longer the gap will be, and finally the displacement position of the fuel injection pump will be displaced. The shaft is broken by being out of focus with the drive shaft.
The solution is to use a suitable thick copper pad as a pad between the pump and the pump base to eliminate the gap. When installing the fuel injection pump, first clean the threaded hole, then tighten the four fixing bolts to the specified torque, and check the coaxiality of the fuel injection pump shaft and the transmission shaft. If it does not meet the standard, it should be re-adjusted. It is recommended to remove the fuel injection pump together with the pump base.