Oil pump is not the cause of the oil pump: 1, the plunger and plunger sleeve wear.
In use process, mechanical impurity in the fuel into the fuel injection pump cavity, the formation of abrasive wear, plus fuel corrosion effect, make the piston and sleeve clearance increases, oil pressure trip cause fuel leakage from the plunger sleeve clearance, the oil supply is insufficient or no oil supply.
2, delivery valve wear.
Mechanical impurity in the fuel delivery valve under high speed flow scouring caused and decompression with or wear and tear and seating is lax, the residual stress in the high pressure oil pipe.
When the fuel injection pump pump oil again, part of the pressure inside the fuel added high-pressure pipe, and therefore to the supplied fuel shortage in the cylinder, serious when no oil supply.
3, delivery valve spring failure.
The oil valve spring use oil valve and valve seat tightly.
Reliable sealing, prevent the backflow of high-pressure tubing fuel.
If the oil valve spring fatigue and tension decreases, and use one-way intercepting effect variation of oil valve, oil reversal phenomenon, with the result and reason and 2)
Described in the same.
4, low oil pressure.
Fuel injection pump hydraulic low pressure oil to a certain extent, to ensure that the fuel rapidly into the pump chamber, ensure the fuel injection pump oil to fuel pump.
If oil transfer pump pump capacity reduction or not pump oil, oil or diesel oil filter, oil plug, or within the fuel oil system in air, etc. , makes the fuel injection pump is reduced, the oil pressure of low-pressure oil does not produce stress, even when the pump work, the fuel can quickly enter the fuel injection pump cavity, cause the fuel injection pump oil or no oil pump.
5, the fuel control rod or governor was stuck in the oil reduce position, or in position to no oil supply, injection plunger stroke effectively reduce or zero, the fuel injection pump or oil.
6, engine speed regulating mechanism for binding or improper adjustment, role in governing spring pressure decreases, and the fuel injection pump oil is limited by the governor, the oil supply shortage.
7, plunger spring failure.
If the plunger spring fatigue due to long compressed or broken, can't guarantee the plunger rallies and a good contact with the CAM roller body.
Makes the plunger stroke decrescent, leading to insufficient oil or no oil supply.
8, CAM and the roller body wear or improper adjustment, can make the plunger lift is reduced, cause insufficient oil supply;
CAM shaft bearing damage, make the CAM shaft radial deviation (
, resulting in decreased pump oil pressure, resulting in reduced the volume of oil supply.
For more than 9, column Qian vice stuck piston and sleeve fit clearance is too small, or diesel oil viscosity is too large;
Adjust the improper roller body (
Adjust the too high)
, plunger lift, the top with oil against and coarsens, being stuck in the plunger sleeve oil supply.
10 improper selection, diesel.
Choose a high solidifying point diesel like winter, because diesel illiquid, fuel can quickly into the pump chamber, resulting in a decrease of oil.
If diesel flow, can cause oil supply disruption;
As summer when choosing low freezing point diesel, because of its viscosity is small, easy to leak, can cause oil supply shortage