The loader in the work process, if the oil pressure is lower than 0.2 MPa (or with the engine speed change fluctuated), should immediately stop the search for reasons, troubleshooting before it can continue to work, otherwise it will lead to the tile burning, cylinder and other major mechanical accident. The main reasons for the low oil pressure are as follows.
(1) insufficient oil
If the amount of oil is insufficient, the oil pump will reduce the amount of oil, leading to lower oil pressure, increasing crankshaft and bearing, cylinder and piston wear.
(2) engine temperature is too high
If the engine temperature is too high, not only to accelerate the aging of the oil, deterioration, but also easy to make oil thinning, leading to oil pressure drops.
(3) the oil pump is stopped or the pump is insufficient
The driving gear of the oil pump and the drive shaft of the fixed pin broken or matching key fall off, and the oil pump suction foreign body and pump oil gear stuck, will cause the oil pump to stop running, oil pressure will be reduced to 0.
When the oil pump shaft and bushing, the clearance between the gear face and the clearance between the pump cover and the clearance or radial clearance due to wear and exceeds the allowable value, will lead to reduce the amount of oil pump, oil pressure caused by the consequences of the decline.
(4) the clearance between crankshaft and connecting rod bearing is too large
When the engine is used for a long time, the clearance between the crankshaft and the connecting rod bearing will increase gradually, and the oil pressure will also decrease.
(5) the oil filter is clogged
When the oil is prevented from circulation due to the clogging of the oil filter, the safety valve on the oil filter base is pushed off and the oil is directly inserted into the main oil passage without filtering. If the safety valve opening pressure is too high, when the oil filter is blocked, the safety valve can not be opened in time, so the oil pump pressure increases, the leakage increases, the main oil supply is reduced, causing oil pressure to drop.
(6) the return valve is damaged or malfunction
If the oil return valve spring fatigue softening or improper adjustment, the valve seat and steel ball matching surface wear or dirt stuck and closed lax, the amount of oil will increase significantly, the main oil road will also decline in oil pressure.
(7) oil radiator or pipe oil leakage;
Oil leakage in oil radiator and pipe will reduce oil pressure. If the pipeline is blocked by dirt, the flow of oil will decrease and the oil pressure will decrease due to the increase of resistance.
(8) the oil pressure sensor fails or the tubing is blocked
If the oil pressure sensor fails or the tubing from the main oil line to the oil pressure sensor is circulating due to accumulation of dirt, the oil pressure gauge will show the decrease of the oil pressure.
(9) the oil pan is blocked
If the oil is too dirty, too sticky, it is easy to plug the suction disc. When the engine throttle low speed, oil pump volume is small, the main oil channel is able to set up a certain pressure, oil pressure will be normal; but when the throttle is running at high speed, the amount of oil pump for suction resistance and significantly reduced, thereby causing the oil pressure gauge shows decreased.
(10) incorrect oil number or unqualified quality;
Different types of engines need to be added different oil, and the same type of machine should be used in different seasons with different grades of engine oil. If the engine oil number is wrong, the engine will be running too low oil viscosity and increase the leakage, thereby reducing the oil pressure.
(11) the setting pressure of the regulating valve is on the low side
If the setting pressure of the regulating valve is low, the oil can not be effectively transported to the lubrication parts, thus mechanical failure occurs. If the oil pressure is too high, it will increase fuel consumption, increase the load on the oil pump and lubrication parts, damage the oil seal, and cause oil leakage.