What if the hand pump can't pump oil? What are the symptoms when the hand oil pump is broken?

There are several related reasons why the hand pump is not oiled.

① The vent hole on the fuel tank cover is blocked, and negative pressure appears in the fuel tank, which affects the normal refueling. The viscosity of diesel oil used in winter is too high and its fluidity is poor. This situation needs to be cleared up in time.

(2) When pumping oil, the fuel spilled by the deflation screw is mixed with gas. If you feel resistance when you press the handle and little fuel is discharged at the same time, it means that the filter element or oil circuit between the oil transfer pump and the high pressure oil pump is blocked and the oil supply is reduced. , need to check whether there is any blockage in the oil path from the oil transfer pump to the high pressure oil pump.

(3) When the exhaust screw is not unscrewed, if the handle is pressed for a long time, the resistance is always small, which means that the oil return valve on the high-pressure oil road or the oil inlet and outlet I valve in the oil transfer pump is poorly sealed and the oil is leaking. If the seal is not tight, the gasket needs to be replaced in time.

It is necessary to check whether the valve surface is seriously worn, whether the valve surface is stained with impurities and whether the internal spring is damaged.

The function of the hand oil pump is to make the oil circuit start to circulate by pumping oil manually, and the air is discharged through the exhaust holes on each component, or discharged into the oil tank through the oil return pipe, so that the whole pipeline is filled with fuel, thus helping the engine to start better.