The excavator may give an oil pressure alarm during use, and some operators do not know what causes it. This article will summarize several causes of the excavator oil pressure alarm.
1. the filter collector is blocked
Under normal conditions, the oil pressure should be higher at high throttle than at low throttle, but sometimes abnormal conditions may occur. If the oil is too dirty and sticky, it is easy to block the filter collector. When the engine runs at a low speed with a small throttle, the oil pressure is normal because the oil pump does not absorb much oil, and a certain pressure can be established in the main oil passage. However, when the throttle is increased and the engine operates at a high speed, the oil absorption of the oil pump will be significantly reduced due to excessive resistance of the filter collector, so the indication of the oil pressure gauge will decrease due to insufficient oil supply in the main oil passage. Clean the suction strainer or change the oil.
2. the bypass valve is damaged
In order to maintain the normal oil pressure of the main oil passage, a bypass valve is set. If the pressure regulating spring is softened or improperly adjusted, the mating surface between the valve seat and the steel ball is worn or stuck, and the valve is not tightly closed, the return oil volume increases, and the pressure of the main oil passage will decrease. At this time, remove the bypass valve for inspection, and finally adjust the pressure to the normal range.
3. the set pressure of pressure limiting valve is too low
In the lubrication system, the oil pumped by the oil pump must ensure appropriate pressure before reaching all lubricating parts of the engine. If the set pressure of the pressure limiting valve is too low, the pressure regulating spring becomes soft or the sealing surface leaks, the set pressure will be too low. At this time, adjust the pressure limiting valve to make the pressure return to normal.
4. the fit clearance between main bearing and connecting rod bearing increases
After the engine has been used for a long time, the fit clearance between the main crankshaft and the connecting rod bearing gradually increases, the leakage increases, and the oil pressure decreases. The pressure will decrease by 0.01Mpa when the fitting clearance increases by 0.01mm. At this time, the crankshaft can be repaired, new connecting rod bearings and main bearings can be selected, and their matching clearance can be restored. In addition, there is too much clearance between camshaft and bearing, crankshaft and crankshaft bearing, rocker shaft and rocker arm.
